1_NCS000442_SWMP_20210708

.iN
.. City of
Rocky Mount
- STORMWATER MANAGEMENT
PLAN
Tar -Pamlico River Basin:
Stormwater Program
- for Nutrient Control
..
."
0.
City Council Action
August 9, 2004

City of
_ Rocky Mount
STORMWATER MANAGEMENT
- PLAN
Tar -Pamlico River Basin:
Stormwater Program
for Nutrient Control
City Council Action
August 9, 2004

Table o, f Contents
-� 1.
Introduction-
1-A. Purpose of the Tar -Pamlico Stormwater Rule._-- -- --- ---------- ---- *......................
1
1-B. Requirements of the Tar -Pamlico Stormwater Rule-------------------- --
.
3
2.
New Development
2-A. Requirements in the Rule--------- --------
6
2-B. Protecting Riparian Areas on New Development-•-----------------------------------------6
_
2-C. CalcuIating Nutrient Export from New Development -------------------------------------
7
2-D. BMPs for Reducing Nitrogen and Phosphorus..............................................10
2-E. Calculating Peak Runoff Volume-----------------------------------------•------.........
12
2-F. Offsite Partial Offset Option ...........................................................................
lb
2-G. Regional or Jurisdiction -Wide Approaches___ --------------------------------
1-7
2-H. BMP Maintenance ............... ..................................................................
20
2-I. Land Use Planning Provisions .. ______________________
20
2-J. References..................................................................................................
23
3.
Illegal Discharges
w
3-A. Requirements in the Rule -------------- ______________________24
3-B. What is an Illegal Discharge? ............................................................... - .........24
3-C. Establishing Legal Authority..................................................................•-•----_25
3-D. Collecting Jurisdiction -Wide Information -------------------------------------------- -----.....
25
3-E. Mapping and Field Screening in High Priority Areas ...................................
26
3-F. Identifying and Removing Illegal Discharges................................................30
--
3-G. Preventing Discharges and Establishing a Hotline....--, .............................31
3-H. Implementation Schedule____________________
31
r.
3-I. References
32
4.
Retrofit Locations
4-A. Requirements in the Rule __33
4-13. Approach for Meeting Requirements.-----------------------------------------------------------
33
4-C. Data Collection and Notification
34
4-D. Mapping Requirements .............. ...........................5
5.
Public Education
5-A. Requirements in the Rule ............................ ___37
5-B. Public Education Action Plan
37
6.
Reporting Requirements
6-A. New Development Review/Approval---
38
6-B. Illegal Discharges .--•--••---------•--------------------------------•••-••-••••••----------------------•----
38
6-C. Retrofit Locations
39
6-D. Public Education .......... ------------------------------ -
39
m" 2

Appendices
Appendix A
Appendix B
Appendix C
Appendix D
Appendix E
Appendix F
Appendix G
Appendix H
Appendix I
Appendix J
Appendix K
Appendix L
Appendix M
Appendix N
Appendix O
Appendix P
Appendix Q
Appendix R
Appendix S
Appendix T
Implementation Schedule and Table of Responsibilities
Local Program Submittal Checklist
15A NCAC 2B .0258 Tar -Pamlico River Basin Nutrient Sensitive
Waters Management Strategy: Basinwide Stormwater Requirements
The Nitrogen Cycle
Sources of Nitrogen in Developed Areas
The Phosphorus Cycle
Sources of Phosphorus in Developed Areas
Export Calculation Worksheets and Supporting Information
Summary of BMP Literature Studies
Computing the Intensity -Duration Variable for the One -Year Storm
in Wake, Wilson, and Craven Counties
Land Use Planning and Design Techniques
Ordinance Establishing Stormwater
Nutrient Management Requirements for New Development
Stormwater Facility Maintenance Agreement
Conservation Easement
Low Maintenance Conservation Easement
Ordinance Establishing Legal Authority
for Illegal Discharge Program
Illicit Discharge Screening Report Form
List of Education Resources
Public Education Action Report
New Development Annual Report Form
0.
3

l . Introduction
The Tar -Pamlico stormwater rule, 15A NCAC 2B .0258, requires that the City of Rocky
Mount develop a local stormwater program. This document and its associated appendices are
intended to establish the methods by which the City of Rocky Mount will comply with the
substantive requirements of the rule.
The intent of this plan is to serve as a guidance document for the operation of the City's
comprehensive stormwater management program as it relates to compliance with the Tar -
Pamlico River Basin - Nutrient Sensitive Waters Management Strategy: Basinwide
Stormwater Requirements. A map of the City's jurisdictional limits is provided in Appendix
A.
In addition to the Tar -Pamlico Basin Regulations, the City of Rocky Mount is also subject to
the NPDES Phase II and the Water Supply Watershed regulations. The City also has a locally
delegated Erosion and Sedimentation Control Program. The intent of the City's stormwater
management program is to integrate the requirements of the Tar -Pamlico regulations with the
requirements of these other programs to have a single comprehensive management strategy
that addresses the requirements of each program with common program elements.
Funding
Primary funding for the City's comprehensive stormwater management program is from the
Stormwater Utility that began operations on July 1, 2003. When the utility began operations
in July 2004 it supported 36 operational and 2 administrative positions. The utility also
receives administrative support from other City departments including Engineering and
Finance.
The stormwater utility is a funding mechanism which equitably distributes the cost of the
stormwater management program among the users based on demand to the system. The
stormwater utility will provide financial support for many of the activities outlined in the plan
but is not relied upon as a legal authority to enforce any provisions of the plan. The
jurisdiction of the utility is limited to the Rocky Mount Corporate limits.
New Development
Elements of the program related to new construction and maintenance of BMPs constructed to
comply with the requirements of the program will be will be enforced by the City within the
City Limits and ETJ as part of its existing land development regulatory process.
Illegal Discharge
The City has traditionally limited its nuisance abatement code enforcement activities to the
City Limits since no supporting revenue in the form of taxes or related fees are levied in the
areas outside the City Limits. The city will continue to follow this model with respect to the
illegal discharge detection and elimination program and does not plan to expend City
resources for mapping or dry weather screening in the ETJ. The City would be willing to
._ provide some portion of these services under contract to the appropriate county provided an

equitable cost sharing arrangement can be made. The program is established pursuant to the
authority contained in G.S. 113A Article 4 (Pollution Control Act), G.S. 143 Article 21
(Water and Air Resources); G.S. 160A- 185 (Emission of pollutants or contaminants) and the •—
requirements of 15A NC AC 2B.0258.
Public Education
Public education and public involvement activities as a matter of policy will be limited to
areas within the city limits for the reasons listed above. It should be noted however, that many
of the public education and involvement activities will be done in cooperation with Nash and
Edgecombe County and by their nature will not limit themselves to a particular political _
boundary. Direct mailings and other activities that are specific to a geographic area and
require significant fund expenditures will be limited to areas inside the city unless they are
done in cooperation with another supporting agency or provide some direct benefit to areas
inside the city.
1-A. Purpose of the Tar -Pamlico Stormwater Rule
The Tar -Pamlico River Basin begins in Piedmont North Carolina and extends approximately
180 miles through the Coastal Plain to Pamlico Sound. Together, Pamlico Sound and
neighboring Albemarle Sound constitute one of the most productive estuarine systems in the
country. The 5,400 square mile Tar -Pamlico basin is comprised primarily of agricultural and
forest land, and many smaller municipalities. Despite the rural character of the basin, in the
mid- 1970's the Pamlico River estuary began to see increasing frequencies of harmful algal
blooms, fish kills, and other nutrient -related problems.
By the mid- 1980's, the state began to consider actions to control nutrient inputs to the estuary.
Those actions have included the following:
Phase I. In 1989, the North Carolina Environmental Management Commission designated the
entire basin "Nutrient Sensitive Waters". The first phase of management through 1994
focused primarily on point sources, establishing an annually decreasing nutrient loading cap
for an association of dischargers, and an innovative "trading" program that allowed
dischargers to achieve reductions in nutrient loading more cost-effectively. ~'
PCS Recycling: In 1992, a phosphate mining company then known as Texas Gulf, which is
located on the Pamlico River estuary, instituted a wastewater recycling system that reduced its
phosphorus discharges to the estuary by 93%.
Phase H. Modeling of estuary conditions showed that despite the gains made to that point,
significant reductions in nitrogen and phosphorus loading were still needed to restore water
quality standards and minimize the recurrence of harmful algal blooms. The second phase of
the nutrient strategy, which runs through 2004, established a biologically based goal of 30
percent reduction in nitrogen loading from 1991 levels and holding phosphorus loading at
1991 levels. Load reductions were apportioned among point sources and the major nonpoint

sources. The point sources were given steady annual nitrogen and phosphorus loading caps.
A program was designed with the nonpoint sources to achieve the goals through voluntary
measures. After two years of voluntary implementation, the Commission found insufficient
progress and called for rules for nonpoint sources.
Rules: Beginning in 1998, DWQ staff conducted a lengthy public input process to evaluate
source categories and develop rules where needed. Over the course of 2000, the Commission
adopted rules for agriculture, fertilizer application across all land uses, urban stormwater, and
rules to protect the nutrient removal functions of existing riparian buffers. These rules were
modeled after a similar set of rules recently adopted in the adjacent Neuse River Basin. The
Neuse rules were given extensive public review and modification, and the Tar -Pamlico rules
similarly received extensive scrutiny. The resulting rules provide increased flexibility for the
regulated community while maintaining the focus of the nutrient reduction goals.
1 B. Requirements of the Tar -Pamlico Stormwater Rule
The Tar -Pamlico stormwater rule applies to the local governments with the greatest likelihood
of contributing significant nutrient loads to the Pamlico estuary. The EMC may designate
additional local governments in the future through rule amendment based on criteria given in
the rule.
The affected local governments are:
Municipalities Counties
Greenville Beaufort
Henderson Edgecombe
Oxford Franklin
Rocky Mount Nash
Tarboro Pitt
Washington
For these local governments, only their geographic areas that fall within the Tar -Pamlico
River Basin are subject to the rule. In subject counties, applicable areas are those under the
direct jurisdiction of the counties, which would not include incorporated cities, towns, or
villages within county jurisdictional limits. Cities and counties are encouraged to coordinate
to establish implementation responsibilities within municipal extraterritorial jurisdictions.
Counties administering development regulations by interlocal agreement on behalf of
municipalities would implement the rule within only those municipalities that are subject to
the rule. The activities of state entities within subject local governments would be subject to
the rule.
The rule establishes a broad set of objectives for limiting nutrient runoff from urban areas. It
then lays out a set of specific elements, described below, that local governments shall include
in their programs. It also sets up a process by which DWQ will work with the affected local

governments to develop a model stormwater program for meeting the objectives. Timeframes
for implementation of the rule are as follows:
April 1, 2001:
Effective date of the rule.
February 13, 2003:
Target date for approval of the Model Stormwater Program by the
Environmental Management Commission (modified through EMC
approval from the date of April 1, 2002 established in the rule).
February 13, 2004:
Deadline for submittal of local Stormwater Programs (including
ordinances) to the EMC (modified as above).
August 13, 2004:
Deadline for local governments to begin implementing local
Stormwater Programs (modified as above).
Following implementation in August 2004 local governments are required to make annual
progress reports to the EMC that will include nitrogen and phosphorus loading reduction
estimates.
The elements that must be included in local stormwater management programs are:
1. New Development Review/Approval
New development is required to meet the 30% reduction goal through site planning and best
management practices. The rule imposes a 4.0 pounds per acre per year (lblac/yr) nitrogen
loading limit and a 0.4 lb/ac/yr phosphorus loading limit on new development. Proposals that
exceed these performance standards may partially offset their load increases by treating
existing developed areas offsite that drain to the same stream.
New development must also avoid causing erosion of surface water conveyances. At
minimum, post -development peak flows leaving the site may not exceed pre -development for
the I -year, 24-hour storm event. The rule also provides local government with the option of
using regional stormwater facilities to help meet nutrient loading and attenuation requirements
under certain circumstances.
2. Illegal Discharges
Illegal discharges are substances deposited in storm sewers (that lead to streams) that should
instead be handled as wastewater discharges. Illegal discharges may contain nitrogen. Local
governments must identify and remove illegal discharges.
3. Retrofit Locations
There are a number of funding sources available for water quality retrofit projects, such as the
Clean Water Management Trust Fund and the Wetland Restoration Program that the NC
General Assembly has recently established. To assist technical experts, local governments are
required to identify sites and opportunities for retrofitting existing development to reduce total
nitrogen and phosphorus loads.
4

4. Public Education
Citizens can reduce the nitrogen pollution coming from their lawns and septic systems if they
understand the impacts of their actions and respond with appropriate management measures.
The local governments will develop and implement public and developer education programs
for the Tar -Pamlico basin.
t

2. New .Development Review/Approval
2-A. Requirements in the Rule
The Tar -Pamlico Stormwater Rule (15A NCAC 2B .0258) has the following requirements
(see the rule in Appendix B for complete language) for new development located within the
planning and zoning jurisdictions of the 11 local governments subject to these rules:
❑ The nitrogen load contributed by new development activities is held at 4.0 pounds per
acre per year. This is equivalent to 70 percent of the estimated average nitrogen load
contributed by non -urban areas in the Tar -Pamlico River basin (as defined using 1995
LANDSAT data). Similarly, the phosphorus load contributed by new development
activities is held at 0.4 pounds per acre per year, which is equivalent to the estimated
average phosphorus load contributed by non -urban areas in the basin. The Environmental
Management Commission may periodically update these performance standards based on
the availability of new scientific information.
❑ Property owners shall have the option of partially offsetting projected nitrogen loads by
providing treatment of existing developed areas off -site that drain to the same stream.
However, the total nitrogen loading rate cannot exceed 6.0 pounds per acre per year for
residential development or 10 pounds per acre per year for non-residential development.
❑ There is no net increase in peak flow leaving the developed site from the predevelopment
conditions for the 1-year, 24-hour storm.
❑ Local governments must review new development plans to assure compliance with
requirements for protecting and maintaining riparian areas as specified in 15A NCAC 2B
.0259.
Local governments may include regional stormwater facilities in their programs to provide for
partial nutrient and flow control. Such facilities may not degrade surface waters.
2-B. Protecting Riparian Areas on New Development
The Tar -Pamlico Riparian Buffer Protection Rule, 15A NCAC 2B .0259, requires local
governments that are subject to the stormwater rule to ensure that riparian areas on new
developments are protected in accordance with the buffer rule's provisions. The buffer rule --
requires that 50-foot riparian buffers be maintained on all sides of intermittent and perennial
streams, ponds, lakes and estuarine waters in the basin. The buffer rule provides for certain
"allowable" uses within the buffer with DWQ approval, such as road and utility crossings.
6

The City will disapprove any new development activity proposed within the first 50 feet
adjacent to a waterbody that is shown on either the USGS 7.5 minute topographic map or the
NRCS Soil Survey map unless the owner can show that the activity has been approved by
DWQ. DWQ approval may consist of the following:
❑ An on -site determination that surface waters are not present.
❑ An Authorization Certificate from DWQ for an "allowable" use such as a road crossing
or utility line, or for a use that is "allowable with mitigation" along with a Division -
approved mitigation plan. A table delineating such uses is included in the buffer rule.
❑ An opinion from DWQ that vested rights have been established for the proposed
development activity.
❑ A letter from DWQ documenting that a variance has been approved for the proposed
development activity.
2-C. Calculating N and P Export from New Development
❑ Built -upon area means that portion of a development project that is covered by
impervious or partially impervious cover including buildings, pavement, and gravel area.
Slatted wooden decks and the water surface area of pools shall be considered pervious.
..� ❑ Land disturbance is defined as grubbing, stump removal, grading, or removal of
structures.
New Development Defined. For the purposes of the Tar -Pamlico Stormwater Program, new
development shall be described to include the following:
❑ Any activity that disturbs greater than one acre of land to establish expand, or replace a
single family or duplex residential development or recreational facility. For individual
single family residential lots of record that are not part of a larger common plan of
development or sale, the activity must also result in greater than ten percent built -upon
area.
❑ Any activity that disturbs greater than one-half an acre of land to establish expand, or
replace a multifamily residential development or a commercial industrial or institutional
facility.
❑ New development shall not include agriculture (including intensive livestock operations),
mining, or forestry activities.
7

Provisions for Re -development Projects: Projects that replace or expand existing structures
or improvements and exceed the land disturbance limits described above are subject to the
following provisions:
❑ Projects that replace or expand existing structures or improvements and that do not result
in a net increase in built -upon area shall not he required to meet the basinwide averse
non -urban loading levels.
❑ Projects located within an area the City of Rocky Mount has designated as a ^'
redevelopment area will not be required to achieve nutrient reductions provided the City
has a specific redevelopment plan in place for the area that meets the following
conditions:
o The re -development area is a historic community center, traditional central business
district, historical district, educational center, or other existing developed area
specifically identified by the City Council.
o The City has an established a strategy, for reinvestment in the area that address the
following criteria as appropriate:
- A "fix it first" policy that reserves public funds for repair of existing
infrastructure in these areas before investing in new infrastructure of the same
type in new growth areas.
- Mixed use/mixed density zoning provisions.
- Retrofits are consistent with NCDOT definitions for pedestrian scale in traditional
neighborhood developments (e.g., 80% of users are within a `/4 mile walk from
schools, libraries, and recreational/athletic facilities, 60% of students and 50% of
teachers are within'/2 mile walk from schools, and 40% of congregants are within
%4 mile of churches).
- Parking maximums or shared parking ratios. -'
- Residential density bonuses where parking maximums, pedestrian scale, or "fix it
first" are proposed.
o The re -development plan is conducive to the goals of the Tar -Pamlico nutrient "~
strategy.
❑ Projects that replace or expand existing structures or improvements resulting in a net
increase in built-1112on area shall achieve a 30 percent reduction in nitrogen loading and no
increase in phosphorus loading relative to the previous development. Such projects may
achieve these loads through onsite or offsite measures or some combination thereof
Multi -family residential, commercial, industrial, and institutional projects may choose
to achieve all of this reduction by providing treatment of off -site developed areas, or
by permanently conserving land from future development in conformance with the
local government's approved land conservation plan, as described in Section 2-G.

Vesting: All new development projects within the City of Rocky Mount Planning Jurisdiction
that have received approval from the City of Rocky Mount, Nash or Edgecombe County for a
site -specific or phased development plan by September 15, 2004, and that have implemented
that development in accordance with the City of Rocky Mount vesting provisions shall be
exempt from the requirements of the Tar -Pamlico stormwater rule. This vesting provision is
predicated on the condition that any plats associated with such development must be recorded
within a maximum of five years from the date of development approval. All new
development projects that have not received such approval by September 1, 2004 or recorded
any plats associated with such development within five years of the development's approval
shall be subject to the requirements of the rule.
Projects that require a state permit, such as landfills, NPDES wastewater discharges, land
application of residuals and road construction activities shall be considered exempt if a state
.. permit was issued prior to the effective date of the local stormwater program.
Calculating N and P Export: The nitrogen and phosphorus export from each new
development must be calculated. This export will be calculated in pounds per acre per year
(lbs/ac/yr). The methodology to make this calculation is described below. The worksheets to
carry out the calculations are provided in Appendix H, along with a description of their
development. (A spreadsheet version of the worksheet can be downloaded from the City of
Rocky Mount web site located at http: //www. ci. rocky -mount. nc. us)
It is expected that some values provided in the methodology will be refined over time. The
NCDENR Division of Water Quality plans to provide those refinements to the jurisdictions on
a periodic basis as they are established. For example, additional research may lead to refined
export values for the various urban land covers, particularly rooftop and transportation
impervious surface. Also, stormwater management practices are typically in various stages of
— refinement around the country. Several nutrient reducing BMPs are being applied and studied
around North Carolina toward better designs and more accurate knowledge of long-term
nutrient removal efficiencies. The NCDENR Division of Water Quality will ask the
jurisdictions to incorporate these refinements into their programs from time to time as they are
substantiated.
For a given project, the methodology calculates a weighted annual load export for both
nitrogen and phosphorus based on event mean concentrations of runoff from different urban
land covers and user -supplied acreages for those land covers. The user chooses BMPs that
-- reduce the export to rule -mandated levels. Two versions of the spreadsheet were developed
based on rainfall differences between the "Piedmont" and "Coastal Plain" ; the "Piedmont"
version (provided in Appendix H) is to be used for all projects in Rocky Mount's jurisdiction.
A residential worksheet is also provided in Appendix H to calculate acreages dedicated to
different land covers in residential developments where impervious footprints are not shown.

2-D. BMPs for Reducing Nitrogen and Phosphorus
The rule requires that all new developments achieve a nitrogen export of less than or equal to --
4.0 (and a phosphorus export of less than or equal to 0.4) pounds per acre per year. If the
development contributes greater than 4.0 pounds nitrogen (or 0.4 pounds phosphorus), then
the following options exist.
❑ If the computed nitrogen export for single family/duplex residential development is
greater than 6.0 lb N/ac/yr or 10.0 lb N/ac/yr for commercial development, then the
development plan must include on -site BMPs or be included in an approved regional or
jurisdiction -wide stormwater strategy or some combination of these to lower the nitrogen
export to at least 6.0 (or 10.0) lb N/ac/yr respectively. The owner may then use one of the
following two options to reduce nitrogen from 6.0 (or 10.0) to 4.0 lb N/ac/yr.
❑ If the computed nitrogen export is greater than 4.0 lb/ac/yr but less than 6.0 (or 10.0) lb
N/ac/yr dependant on development type, then the owner may either:
■ Provide treatment of an offsite developed area that drains to the same stream to
achieve the same nitrogen mass loading reduction that would have occurred onsite.
Or;
lnstail BMPs onsite or take part in an approved regional or jurisdiction -wide —
stormwater strategy or some combination of these to remove nitrogen down to 4.0 lb
N/ac/yr. Participation in regional or jurisdiction -wide stormwater facilities and/or
strategies is subject to development and approval of such facilities or strategies and any conditions and/or limitations that may be a part of the strategy or facility.
❑ The owner must install BMPs that also achieve a phosphorus export of less than or equal
to 0.4 lb P/ac/yr, but may do so through any combination of on -site and offsite measures.
As with most resource impacts, an ounce of stormwater prevention is worth a pound of cure. —'
A sound site planning process first considers the ability to achieve the needed reductions using
site design measures that avoid or minimize runoff to begin with. The accounting method in
Section 2-C provides credit for site planning practices that reduce nutrient loadings in this
manner. These planning measures include reducing, disconnecting, and rerouting impervious
surfaces, maximizing time of concentration for stormwater, and protecting open spaces for
infiltration and evapotranspiration. More detail on planning measures that reduce hydrologic
and nutrient loading is given in Appendix L.
Often, structural management practices cannot be avoided. BMP selection is an important and
challenging craft. Available data indicate that most BMPs remove only 20 to 40 percent of
total nitrogen or phosphorus on a consistent basis. There are a number of issues to consider to
ensure this sustained performance. It is crucial to consider the issues of aesthetics, long-term
maintenance, safety and reliability in BMP design. All BMPs require regular maintenance
and some have varying performance depending on soil type and season. The efficiencies
provided below and in the load calculation worksheets in Appendix H assume correct sizing
[Li

and other design per the referenced manuals, and optimum performance based on regular,
effective maintenance as well as proper siting of the practices.
The BMPs available for nutrient reduction and their removal rates based on current literature
studies are provided in Table 2c below. These median values are based on a literature review
conducted by a contractor that updated Neuse nitrogen efficiencies and established
phosphorus values. A summary of these literature studies is given in Appendix I. Also
provided in the table are the design standards to be adhered to in permitting BMP design,
The design of best management practices that remove nitrogen and phosphorus from
stormwater is a developing field. Researchers throughout the country, particularly in the
Southeast, are conducting studies to identify and refine effective means of controlling nitrogen
and phosphorus. As stated in Section 2-C, the NCDENR Division of Water Quality plans to
�. provide refinements in the stated BMP removal efficiencies to the jurisdictions on a periodic
basis as they are substantiated.
Table 2c: BMP Types, TN and TP Removal Rates, and Design Standards
TN Removal
TP Removal
BMP Type
Rate per
Rate per
Appropriate Design Standards
Literature
Literature
Review
Review
Wet detention ponds
25%
40%
NC Design Manuals
Constructed wetlands
40%
35%
NC Design Manuals
Restored riparian buffers
30%
30%
Tar -Pamlico Riparian Buffer Rule
15A N CAC 2 B .0259
Grass Swales
20%
20%
NC Design Manuals
Vegetated filter strips
30%
30%
NC Design Manuals and other literature
with levels reader
information
Bioretention raingardens)
40%
35%
NC Design Manuals
Sand Filters
35%
45%
NC Desi n Manuals
Proprietary BMPs
Varies
Varies
Per manufacturer subject to DWQ a roval
Other BMPs
Varies
Varies
Subject to DWQ approval
The design manual for the City of Rocky Mount does not currently contain any standards for
design of water quality BMPs and therefore the City will defer to the design standards
referenced in Table 2c for the design of water quality BMPs. The North Carolina BMP
Design Manual can be accessed and downloaded from the DWQ Stormwater Unit's web page
at htW:/ih2o.enr.state,nc.us/su/stormwater.htmI or obtained by contacting the Stormwater Unit at 919-
733-5083 ext. 545. The City may choose to incorporate water quality design standards into its
manual at some point in the future but development of these standards is not a specific
element of this plan.
Multiple BMPs: The worksheet provides calculation space for the case where more than one
^' BMP is installed in series on a development. It determines the removal rate through serial
rather than additive calculations. This is important to understand in projects where the
automated worksheet is not used to estimate the effect of multiple BMPs.

As an example, if a wet detention pond discharges through a restored riparian buffer, then the
removal rate shall be estimated to be 47.5 percent, determined as follows. The pond removes
25 percent of the influent nitrogen mass and discharges 75 percent to the buffer. The buffer
then removes 30 percent of the remaining 75 percent of the original nitrogen amount that
discharged from the pond, or 22.5 percent of the original influent amount. The sum of 25 and
22.5 is 47.5. The removal rate is NOT 25 percent plus 30 percent.
Assigning Values to Pervious Cover: Many development plans may involve open space that, !"
at least initially, is shown as low maintenance pervious., wooded or reforesting condition.
While it may seem logical to enter this acreage as wooded pervious, without conservation ..
easements or some other mechanism for ensuring protection of these areas, the City of Rocky
Mount has no control over their eventual condition. Thus, conservation easements (Appendix
N), low maintenance easements (Appendix O) and/or operation and maintenance (O&M)
agreements (Appendix M), consistent with the requirements of the BMP used, will be required
for all pervious areas not declared as lawn/landscape managed pervious in the development
plan.
Riparian buffers protected under the Tar -Pamlico Riparian Buffer Protection rule, 15A NCAC
2B .0254, are divided into two zones, moving landward from the surface water, that are
afforded different levels of protection. Zone 1, the first 30 feet, is to remain essentially
undisturbed, while zone 2, the outer 20 feet, must be vegetated but may be managed in certain
ways. The user shall enter the acreage in zone 1 into the worksheet as wooded pervious, while
zone 2 acreage shall be entered as managed pervious (lawn/landscape). Zone 2 may be
counted as low maintenance pervious or wooded area only if placed in a conservation
easement and managed in accordance with the guidelines specified therein.
2 E. Calculating Peak Runoff Volume
The Tar -Pamlico Stormwater Rule requires that new development not cause erosion of surface �.
water conveyances. At a minimum, new development shall not result in a net increase in peak
flow leaving the site from pre -development conditions for the 1-year, 24-hour storm event. A
number of Neuse local governments sought to use the 2-year rather than the 1-year storm as
the design storm for peak flow control given that the 2-year storm is more consistent with
current hydrologic modeling methodologies.
The main reason that the rule requires a 1-year design storm for peak flow control is to protect
stream channels from erosion. Development on land causes many changes in stormwater
hydrology. One of the major causes of streambank erosion in urban streams is the increase in -�
the frequency of the bankfull-flooding event. The bankfull-flooding event generally occurs at
approximately a 1.5-year frequency. The Tar -Pamlico Stormwater Rule requires control of
the 1-year storm to predevelopment levels to insure that the rate of release will be below
bankfull and therefore less erosive to the stream channel. Releasing the 2-year storm at
12

predevelopment levels would likely have the effect of increasing the frequency of a storm that
is just a bit larger than the most erosive storm.
Protecting streambanks from erosion is a crucial part of the overall Tar -Pamlico Nutrient
Sensitive Waters Management Strategy. Riparian buffers are protected under this program
because in most situations they are effective at removing nitrogen resulting from nonpoint
source pollution. The use of nitrogen reducing BMPs on new development does not obviate
the need to maintain valuable riparian buffers.
-� The 1-year Design Storm
The US Weather Bureau (Technical Paper 40) published maps of rainfall depths for the l-year
storm of duration 30 minutes to 24 hours. The l-year, 24-hour precipitation, as given in this
~" atlas, varies along the Tar -Pamlico River Basin as illustrated in Table 2b below.
Table 2d: Rainfall depths for the 1-year, 24-hour storm (from US Weather Bureau
Technical Paper 40)
Municipality
lyr— 24hr
depth inches
County
lyr— 24hr
depth inches
Oxford
2.9
Henderson
2.9
Franklin
3.0
Rocky_Mount
3.2
Nash
3.1
Tarboro
3.3
Ed ecombe
3.2
Greenville
3.4
Pitt
3.4
Washington
3.5
Beaufort
3.5
The Rational Method is an acceptable method for estimating peak discharge in the design of
.. stormwater facilities for relatively small watersheds (up to 50 acres). The basic equation is:
Q = CIA
Where: Q is the peak flow for the design storm in cubic feet per second
C is the coefficient of runoff based on land cover (dimensionless)
I is the storm intensity in inches per hour
A is the drainage area in acres
The rational equation is based upon the assumption that rainfall is uniformly distributed over
the entire drainage area at a steady rate, causing the flow to reach a maximum at the outlet of
the watershed at a time to peak, Tp. The Rational Method typically gives a conservative
estimate of runoff.
In order to use the Rational Method to determine peak flows, it is necessary to compute the
storm intensity in inches per hour for the 1-year storm. The intensity is computed by the
formula:
I = g/(h+Tc)
Where: I is the storm intensity in inches per hour
13

g and h are empirically derived constants
Tc is the duration in minutes (or (L3/H)O"")1128)
The values for constants g and h for the one-year storm are not presently available. The
appropriate values for g and h were estimated by graphing the 2, 5, 10, 25, 50 and 100-year
values of g and h for Wake and Wilson Counties as a function of return period on a log-
normal scale and determining the y-intercept of the best -fit line (see Appendix J). The
resulting values for g and h are directly applicable in the Tar -Pamlico River basin as follows:
Table 2e: Values of g and h for the One -Year Storm
Values From
Applicable Location in Tar -Pamlico Basin
Value of
Value of h
Wake Count
Oxford, Henderson, and Franklin County
104
18
Wilson County
Rocky Mount, Tarboro, and Greenville
Nash, Ed ecombe, and Pitt Counties
112
20
Craven County
Washington and Beaufort County
127
22
Subtituting the appropriate values for Rocky Mount yields the following result:
Rainfall Intensity (l)
1 yr 24hr (mrhr)
5.00
4.50
4.00
3.50
3.00
2.50
a 2.00
1.50
1.00
0.50
000
0 30 60 90 120 150 180 210 240 270
Tc (min)
Exceptions to the Peak Flow Requirement
Peak flow control is not required for developments that meet one or more of the following
requirements:
❑ The increase in peak flow between pre- and post -development conditions does not exceed
ten percent (note that this exemption makes it easier to conduct redevelopment activities).
❑ The proposed new development meets all of the following criteria: overall impervious
surface is less than fifteen percent, and the remaining pervious portions of the site are
utilized to the maximum extent practical to convey and control the stormwater runoff.
Tc
min
I
in/hr
5
4.48
1
3.73
1
3.20
2
2.8
25
2.49
35
2.04
40
1.87
4
1.72
5
1.60
6
1.4
9
1.02
120
0.80
240
0.43
14

❑ The Director of Engineering makes a determination that stormwater detention in the
location of the development plan will negatively impact existing drainage problems in the
area. These problems may include but are not limited to creation of tailwater problems
on upstream systems, development of concurrent peaks, erosion concerns and other issues
unique to the area.
Acceptable Methodologies for Computing Peak Flow
Acceptable methodologies for computing the pre- and post -development conditions for the
design storm and sizing stormwater controls include:
❑ The Rational Method.
❑ Dr. Rooney Malcom, P.E., Small Watershed Method
❑ NRCS Methodologies applied through the Corps of Engineers HEC-1 Program
❑ The Peale Discharge Method as described in USDA Soil Conservation Service's
Technical Release Number 55 (TR-55).
-- The same method must be used for both the pre- and post -development conditions. and must
be appropriate to the stormwater basin size and BMP. Additional details on allowable design
methodologies are provided in the City of Rocky Mount Standard Specifications and Design
Manual.
2-F. Offsite Partial Offset Option
The Tar -Pamlico stormwater rule provides the option to partially offset nitrogen load
increases from new development by providing treatment of offsite developed areas. The
+' offsite area must drain to the same classified surface water as the new development, as defined
in the schedule of Classifications, 15A NCAC 2B .0316 and listed in Table 2f of this chapter.
The developer must also provide appropriate legal measures to ensure that the offsite area
achieves and maintains the credited nutrient reduction for as long as the new development
exists, including through changes of ownership on either property.
In order to take advantage of the partial offset option, the development plan must meet the
following conditions:
❑ The offsite facility must drain to the same classified surface water as the new
development.
❑ The new development must first reduce nitrogen export from the site to at least 6 lb N/ac-
yr for residential and 10 lb N/ac-yr for other types of development. The balance of the
nitrogen removal must be made by the offsite facility.
❑ The net phosphorus loading for the project must be reduced to 0.4 lb/ac/yr. Some or all
-� of the reduction may be obtained through the offsite BMPs
❑ The offsite facility may only be used to address only the nutrient requirements, unless the
development proposal demonstrates that meeting some or all attenuation requirements
-� offsite will not result in degradation of surface waters to which the new development site
discharges.
15

❑ The off site BMP may serve multiple projects provided the facility is appropriately sized
and an a tracking system to allocate nutrient removal is in place and the off -site facility
has been approved as a regional BMP.
❑ Both the development owner and the owner of the offsite facility must agree in a
documented, enforceable manner that offsite facilities are dedicated to achieving the
specified nutrient and flow reductions for the life of the new development. The
responsibility for maintaining these reductions as well as the provisions of any required
conservation easements and operation and maintenance agreements shall run with the
land and be binding upon subsequent owners of both the development project and the off
site BMP.
❑ The operation and maintenance agreement shall require an annual inspection by a
^
licensed professional and shall ensure that the City of Rocky Mount has the authority to
inspect the stormwater facilities and make any necessary corrections if the owner fails to
complete the required inspection or complete any required improvements. Any costs .�
associated with this work, including administrative costs and fines, will be charge to the
owner or party legally responsible for maintenance of the facility.
^
Many individual developments include stormwater designs that could be interpreted as "off -
site" or "regional" under the broadest of definitions, but which are not intended for the type
of review and approval process described here. Projects such as phased developments or --
commercial projects with outparcels may propose using shared stormwater facilities that
receive runoff from more than one lot and that would be accessed by lots under different
ownership at different points in time. These shared facilities are not considered "off -site" or
"regional" and may be permitted as "on -site" facilities not subject to the pre-treatment
limitations defined above.
I-.
16

The classified surface waters in the City of Rocky Mount include the following:
-^ Table 2f: Tar River Basin Classified Surface Waters
..
Receiving Stream Name
Stream Segment
Water Quality
Use Support
Water Quality
Classification
Rating
Issues
Tar River
4000' upstream of
WS-IV, NSW, CA,
reservoir dam to
(28-64)
dam
Tar River
Reservoir dam to
WS-IV, NSW (28-64.5)
Maple Creek
Grape Branch
Source to Tar River
WS-IV NSW 28-65
Maple Creek
Source to Tar River
WS-IV NSW 28-66
Tar River
Maple Creek to 100'
WS-IV, NSW (28-66.5)
downstream of old
CRM intake of HWY
64
Tar River
CRM intake to RM
B, NSW (28-67)
Mills Dam
Stoney Creek
Source to Tar River
C, NSW (28-68)
PS
Cause Unknown,
PPI High
Tar River
RM Mills dam to 0.9
WS-IV, NSW (28-69)
mi downstream
Buck Swam
Goose Branch
Source to Tar River
C NSW 28-70
Cowlick Branch
Source to Tar River
C NSW 28-71
Compass Creek
Source to Tar River
C NSW 28-72
Hornbeam Branch
Source to Compass
C, NSW (28-72-1)
Creek
Gay branch (Indian Branch)
Source to Tar River
C NSW 28-72.5
Buck Swamp
Source to Tar River
C NSW 28-73
Beech Branch
Source to Hwy 301
B NSW 28-75- 1
Beech Branch
Hwy 301 to Falling
C, NSW (28-75-(2))
Run
Little Cokey Swamp
Source to Cokey
C, NSW (28-83-3-1)
Swam
2-G. Regional or Jurisdiction -Wide Approaches
The Tar -Pamlico stormwater rule provides the option for local governments to develop
^, regional or jurisdiction -wide stormwater facilities in their programs as an alternative means
for developers to address nutrient or flow control requirements. Should the City of Rocky
Mount identify viable regional or jurisdiction -wide projects, it will demonstrate that such
measures will not contribute to degradation of surface waters and quantify nutrient and flow
reductions and provide for tracking and administration of the use of such facilities to DWQ.
Regional Facilities: Within the context of this plan, regional facility means a stormwater
facility that serves a large developed area and serves more than one development draining to
the same classified water. Examples of regional facilities may include but are not limited to
-- wet detention ponds or constructed wetlands.
17

The regional system option will be evaluated by the City through a series of basin master
plans or as specific opportunities are identified through other processes. The regional option -�
would be pursued to provide greater flexibility to development in the impacted area by
constructing stormwater management facilities on a larger scale. Two basic types of regional
facilities may be described as off -stream and in -stream. While the City may pursue in -stream
regional facilities, instream facilities involve a more complicated set of issues associated with
protection of surface waters, they are potentially suitable to a relatively small set of
circumstances.
Regional facilities provided for in this plan may serve more than one development project.
They may also be publicly or privately owned, but would be proposed to DWQ with the
support of the City. Basic elements of regional system proposals, to be permitted by DWQ,
and other "shared -facility" individual projects permitted by local governments would be the
same, and are described below. Regional facilities implemented under the authority of the
City may operate as a "Jurisdiction -Wide" approach and provide offsets for projects
throughout the jurisdiction. ...
As mandated by the rule, such strategies would demonstrate that any proposed measures will
not contribute to degradation of surface water quality, degradation of aquatic or wetland --
habitat or biota or destabilization of conveyance structure of involved surface waters. .
Jurisdiction -Wide Approach: Within the context of the rule and this plan, means generally a —�
nutrient -reducing management measure or strategy implemented under the authority of the
City to offset one or more increases that may take place in the same or a separate watershed
within the jurisdiction. An offsite offset project (see Section 2-F) that is implemented under
the authority of the City to serve projects in multiple watersheds would be a specific type of
jurisdiction -wide approach. Examples of nutrient reducing measures may include but are not
limited to conventional stormwater facilities, constructed wetlands, or land conservation.
The City of Rocky Mount controls a significant amount of land that may be suitable for
conservation easements and reforestation and will likely consider development of specific
proposals for land conservation offsets in the future. When developing a land conservation
proposal for DWQ review, the City will consider the following criteria:
❑ Conserved land would need to achieve the net nutrient reductions not achieved by new
development that conservation is credited with offsetting. Proposals would need to
quantify those reductions, including a measure of uncertainty. Land conservation would ,..,
need to occur as part of some activity that would allow the conservation to achieve
nutrient reductions. Examples include:
■ Conservation of a portion of a new development site to receive and treat the runoff
from the development.
■ Conservation of a portion of some other, concurrent new development site to receive
and treat runoff from that other site.
18

■ Restoration of the buffering functions of undeveloped land adjacent to existing or new
development, e.g. converting pipe or ditch flow to dispersed sheetflow through
forested land.
■ Obtaining and retiring agricultural land to forest land.
❑ The conserved land should be no further from the estuary than the new development and
within the same jurisdiction. Proposals to establish interlocal agreements that would
provide for development and offsetting conservation in different jurisdictions shall
provide adequate assurance of enforceability between jurisdictions, as well as cross -
jurisdictional tracking and monitoring procedures, in addition to the proposal information
called for below.
❑ Adjacent new development could not claim credit for conserved lands that are being
credited to other new development (no double counting).
❑ Lands whose nutrient removal functions are established and protected through other
regulatory programs, such as wetlands and riparian buffers, would not be eligible for
conservation credit.
❑ Conserved land could be used to offset flow attenuation requirements if adequate
measures are provided to ensure diffuse flow and no hydrologic degradation of the
conserved features or surface waters.
❑ The conserved land would be established within the context of a long-term regulating
plan for development in the local government's comprehensive plan.
❑ It should be secured in a permanent conservation easement or equivalent legal mechanism
whose provisions prohibit both farming and unapproved logging practices. This
conservation land should be tracked on a G1S system and recorded on the plat or deed.
An example conservation easement is provided in Appendix N.
^" Proposal Information: Regional or jurisdiction -wide approaches will be undertaken on a
project by project basis and will be incorporated into the City's comprehensive stormwater
management program as they are developed provided there is appropriate supporting
information to show how they will achieve the nitrogen and phosphorus loading reduction
requirements applicable to new development. Whether a regional or jurisdiction -wide
approach is designed, implemented, and maintained by a developer or the local government,
the City will provide the following information to DWQ for any proposed regional facility.
❑ System location and design information, including:
■ land uses in the contributing area
■ type of facility — treatment, attenuation, both, treatment method, expected nitrogen
-- and phosphorus removal efficiency
■ worst -case percent impervious of the contributing area at build out
■ assumptions for on -lot treatment and attenuation
■ calculations on nitrogen and phosphorus reduction needed, demonstration that facility
meets needs
■ demonstration that any proposed measures will not contribute to degradation of
surface water quality, degradation of aquatic or wetland habitat or biota, or
destabilization of conveyance structure of involved surface waters.
19

❑ Process for tracking expenditure of treatment and attenuation capacity.
❑ Facility protection provisions - an easement, restricted to storm water management and
containing adequate access, dedicated to the public or public entity through a platted and
recorded map. An example conservation easement is provided in Appendix N for
projects where such an instrument would be appropriate.
❑ Operation and maintenance provisions:
■ An agreement that demonstrates that (a) the developer, (b) a local government, or (c)
a private for -profit or non-profit company will operate and maintain the facilities.
Example maintenance agreements are provided in Appendix M.
■ Financial guarantees for maintenance of continued performance in the event that the
local government must assume maintenance.
■ an adopted ordinance providing for fines and penalties to ensure maintenance of the
stormwater facilities. An example ordinance is provided in Appendix L.
2-H. BMP Maintenance
If BMPs are implemented to achieve the nitrogen and phosphorus loading and flow
attenuation requirements for a development, then the City will require a maintenance plan for
the BMPs at the time of construction to ensure long term maintenance of the facility. For
projects under its jurisdiction, the City will ensure BMP maintenance through the following
method:
The City Land Development Code requires the formation of a property owners
association, as needed, and a legal agreement with the owner or owners association for
maintenance of the BMP. The provisions of agreement will be required to run with the
land. The City will undertake an annual inventory of BMPs to ensure that the required
inspections and maintenance activities have been completed. If the owner does not
complete the required inspections by a qualified professional or required maintenance in a
timely manner, the City will pursue enforcement actions consistent with the provisions of
the agreement and current code enforcement provisions.
The City will maintain an inventory of BMPs and their locations to assist in the inspection
process.
2-L Land Use Planning Provisions
This section was intended to give some background on what the City has done to reduce
development impacts on water quality. The checklist provided in the model plan was used as
guidance in developing this narrative. There are no specific plans for further revisions to the
Land Development Code but the City will continue to evaluate the impact of development
standards on water quality and will make recommendations to City Council when deemed
appropriate.
20

Challenged by the devastation of the 1999 Hurricane Floyd flood, the City has come through
adversity looking for ways to protect and improve the quality of its water resources, the
preservation of the natural environment, the health and safety of it's citizens, the aesthetic
quality and economic vitality of the community. A significant step to defining the issues and
making initial decisions came in the form of the adopted plan, Together Tomorrow — Tier 1
Smart Growth Comprehensive Plan for the Ci of Rocky Mount This document, adopted
June 9, 2003, analyzes existing conditions for the community in a broad comprehensive
manner, identifies outstanding issues, and provides for publicly developed goals and strategies
to the horizon year of 2025. Implementation of the individual strategies was then organized in
Chapter 14 by responsible parties and time frame for completion.
The Comprehensive Plan is being used as a daily decision making guide for City.
Policies, capital improvement projects and programs are evaluated for compliance
against the Comprehensive Plan which in turn provides the structure to support the
stormwater supportive strategies included therein. For instance, the recent Collector
Street Project was reviewed for compliance with the Comprehensive Plan including
the Critical and Sensitive Designation and altered to comply with these stormwater-
sensitive concepts.
Without doubt, the most important implementation to the Plan is the current Land
Development Code project. Currently underway, the LDC will affect every aspect of our
future development. As the first new version of the City's developmental code in nearly thirty
years, there are innumerable issues being considered. As with many topics, the delicate
balance between optimal and sometimes -conflicting developmental forces are always to be
considered. The LDC is currently under review and discussion for input to decide these issues.
In general, they fall into the following broad categories:
Floodplain Issues —
The City's requirements in dealing with development in the floodplains has continued
to be expanded providing additional support for open areas along water ways and
protection of sensitive low lying areas. No development is permitted in the floodway,
and the city requires additional elevation over the base flood elevation in the I00-year
floodplain (freeboard). The release of the initial FIRM maps in 2003 caused concern of
the proper approach to deal with these issues until the maps had been finalized. The
response was to utilize both 1982 approved maps and the preliminary maps in order to
provide the most protection possible and to comply with NFIP requirements.
Open Space Planning and Preservation of Natural Resources -
The recognition of natural open space as important to the quality of life and
environment is central to Comprehensive Plan concepts. - The Comprehensive Plan
calls for the preservation or restoration of wetlands; focus on open space preservation
with particular attention to the Tar River and its tributaries, and for protection of
woodlands and stream corridors during construction as well as the use of conservation
easements.
^ 21

Open space planning is currently supported with such things as reinforcement of
Riparian buffer requirements and cluster development standards. The LDC supports
the cluster concept by allowing increased density coupled with the dedication of open
space. The opportunity to develop additional developmental forms promoting open
space planning is tied to the Smart Growth Areas as identified in the Comprehensive
~
Plan.
Tree preservation has been an important topic for the LDC. The current draft provides
for the preservation an undisturbed natural tree buffer on perimeter areas of new
development. Tree coverage for non-residential areas has been expanded from the
prior requirements. In addition, the development of residential lots will require
planting or preservation of trees prior to issuance of the certificate of occupancy.
Developmental Standards for Subdivisions and Commercial Construction -
Together Tomorrow identifies the Traditional Neighborhood Design as being a desirable
developmental pattern. This concept places activity centers such as schools and neighborhood
commercial centers within easy walking and biking distances. The compact distances can --
work to reduce the need for impervious redundant street surfaces and parking by replacing
some trips to multimodal instead of total dependence on vehicular travel. In addition, the
LDC allows for Planned Density Residential (PDR) Developments with mixed uses that will
also encourage the integration of residential and commercial uses and are designed to decrease
dependence on driving. Smart Growth Areas provide particular opportunity for such
developmental patterns coupled with open space planning to improve the overall opportunities -'
for stormwater absorption into the natural environment and the reduction of damaging runoff
into the tributary system. In promoting traditional neighborhood design and multi -modal
transportation, a critical element is the appropriate use of sidewalks. While increasing the
impervious surface, sidewalks contribute to the overall welfare of system in a positive
way. The LDC draft has an increased presence of sidewalks in the community for these
reasons. Also under consideration includes parking requirements, widths of streets, driveway
requirements.
"The quantity of natural and manmade pollutants draining into these systems
directly affects the quality of both ground and surface water. For this reason, it is
important to insure that development occurs in a manner that preserves the vital
function of these waters. In some instances this means that better control of storm
water runoff is needed, while in others the density development must be limited so that
functional capacity of the water is not compromised." Source - Together Tomorrow -
Tier I Comprehensive Plan
The City has shown significant commitment to stormwater management, creating a new ~
position, a new utility fee, and increased regulation to improve the quality of response. In the
future, more decisions will be made which must balance stormwater sensitive concepts to
other issues of function, aesthetic, economy and cultural sensitivities. The City will continue
to look at each issue with a pragmatic and critical eye to ensure we are doing our utmost to
protect our water resources for the future.
22

2-J. References
Arendt, R. Open Space Design Guidebook: Albermarle-Pamlico Estuarine Region. 1993.
Prepared for the NC Association of County Commissioners. National Lands Trust.
Media, PA. 259 pp.
Environmental Protection Agency. Office of Water. November 1994. Section 319 Success
Stories.
Environmental Protection Agency. Office of Water. ran. 1993. Guidance Specifying
Management Measures for Sources of Nonpoint Pollution in Coastal Waters.
Washington, DC.
.-. Land of Sky Regional Council. 1995. Stormwater Fact Sheet Number 8: Plan Early for
Stormwater in Your New Development. Asheville, NC. 4 pp.
Schueler, T. S. Dec. 1995. Site Planning for Urban Stream Protection. Metropolitan
Washington Council of Governments. Silver Spring, MD 231 pp.
StimmeI Associates. 1993. Traditional Neighborhood Development Design Guidelines.
Chapel Hill, NC.
23

3. Illegal Discharges
3-A. Requirements in the Rule
The Tar -Pamlico Stormwater Rule requires that all municipalities establish a program to
prevent, identify and remove illegal discharges. Illegal discharges are flows in the stormwater `
collection system that are not associated with stormwater runoff or an allowable discharge.
3-B. What is an Illegal Discharge?
Stormwater collection systems are vulnerable to receiving illegal discharges (even though the
person responsible for the discharge may be unaware that it is illegal). Depending on their
source, illegal discharges may convey pollutants such as nutrients, phenols, and metals to
receiving waters. Table 3a identifies some potential flows to the stormwater collection system
that may be allowable. Table 3b identifies some discharges that are not allowed.
Tahle 3a: Discharaes that may be allowable to the stormwater collection system
Waterline Flushing
Landscape Irrigation
Diverted Stream Flows
Uncontaminated Rising
Uncontaminated Ground
Uncontaminated Pumped
Ground Water
Water Infiltration to stormwater
Ground Water
collection system
Discharges from potable
Foundation Drains
Uncontaminated Air
water sources
Conditioning Condensation
Irrigation Water
Springs
Water from Crawl Space
Pumps
Footing Drains
Lawn Watering
Non-commercial Car Washing
Flows from Riparian Habitats
NPDES permitted discharges
Street wash water
and Wetlands
Fire Fighting Emergency
Wash Water from the
Dechlorinated backwash and
Activities
Cleaning of Buildings
draining associated with
swimming pools
Table 3b: Types of Discharges that are not allowed to stormwater collection system
Dumping of oil, anti -freeze,
Commercial Car Wash
Industrial Discharges
paint, cleaning fluids
Contaminated Foundation
Cooling water unless no
Washwaters from commercial
Drains
chemicals added and has
1 industrial activities
NPDES permit
Sanitary Sewer Discharges
Septic Tank Discharges
Washing Machine Discharges
Chlorinated backwash and
draining associated with
swimming pools
24

3-C. Establishing Legal Authority
One of the first steps that each local government is required to take is establishing the legal
authority to control illegal discharges. According to the policies of each individual Iocal
government, this legal authority may be carried out through ordinances, policies, city codes or
charters.
By August 2004, the City is required to show that it has established the legal authority to do
the following:
• Control the contribution of illegal pollutants identified in Table 3b to the stormwater
collection system.
• Prohibit illegal discharges to the stormwater collection system.
• Prohibit discharge of spills and disposal of materials other than stormwater to the
stormwater collection system.
• Determine compliance and non-compliance.
• Require compliance and undertake enforcement measures in cases of non-compliance.
A copy of the ordinance which establishes this authority for the City of Rocky Mount is
provided in Appendix P. This ordinance will be applied within the city's corporate limits as
defined in the ordinance and enforced through the provisions defined in the ordinance.
3-D. Collecting Jurisdiction -Wide Information
The City will collect geographic information at three increasing levels of detail:
• The first, most cursory level is information that shall be collected for the entire
jurisdiction. The associated requirements are discussed in this section.
• The second level will be a more detailed screening for high priority areas within the
jurisdiction. The associated requirements are discussed in Section 3-E.
• The third level will be a detailed investigation to be completed upon the discovery of an
illegal discharge. The associated requirements are discussed in Section 3-F.
The purpose of collecting jurisdiction -wide information are to assist with identifying potential
illegal discharge sources and characterizing illegal discharges after they are discovered.
The City will fulfill this requirement by compiling maps and G1S coverages that show the
following information. Pursuant to the requirements of the model plan, the maps shall be at a
scale no greater than 1:24,000.
• Location of sanitary sewers in areas of the major stormwater collection systems and the
location of areas that are not served by sanitary sewers.
• Waters that appear on the USDA — Natural Resources Conservation Service Soil Survey
Maps and the U.S. Geological Survey 1:24,000 scale topographic maps.
25

• Land uses. Categories, at a minimum, should include undeveloped, residential,
commercial, agriculture, industrial, institutional, publicly owned open space and others.
• Currently operating and known closed municipal landfills and other treatment, storage,
and disposal facilities, including for hazardous materials.
• Major stormwater structural controls.
• Known NPDES permitted discharges to the stormwater collection system (this list can be
obtained from the Division of Water Quality).
Written descriptions will be provided for the map components as follows:
• A summary table of municipal waste facilities that includes the names of the facilities, the
status (open/closed), the types, and addresses.
• A summary table of the NPDES permitted dischargers that includes the name of the permit
holder, the address of the facility and permit number. '�-
• A summary table of the major structural stormwater control structures that shows the type
of structure, area served, party responsible for maintaining, and age of structure to the
extent it can be determined.
• A summary table of publicly owned open space that identifies size, location, and primary
function of each open area.
The City will complete this collection of jurisdiction -wide information by the time the second
annual report is due (October 2006).
3-E. Mapping and Field Screening in High Priority Areas
Beginning in the third year after implementation of the local stormwater program (2007), the
City will identify a high priority area of its jurisdiction for more detailed mapping and field
screening. This high priority area shall comprise at least ten percent of the jurisdictional area.
Each subsequent year, the City will screening another high priority area that comprises at least
ten percent of its jurisdiction. ^
"High priority" means the areas within a jurisdiction where it is most likely to locate illegal
discharges. Based on the experiences of Raleigh and Durham, the most likely locations for
identifying illegal discharges are areas with older development. Each annual report will
include the basis for selection of the high priority areas screened.
26

The first part of the screening process for the selected high priority area will be to map the
stormwater system. At a minimum, the map that is produced will include the following:
• Locations of the outfalls, or the points of discharge, of any pipes from non -industrial areas
that are greater than or equal to 36 inches.
• Locations of the outfalls of any pipes from industrial areas that are greater than or equal to
12 inches.
• Locations of the outfalls of drainage ditches that drain more than 50 acres of non-
industrial lands.
Locations of the outfalls of drainage ditches that drain more than 2 acres of industrial land.
• An accompanying summary table listing the outfalls that meet the above criteria that
includes outfall ID numbers, location, primary and supplemental classification of
receiving water, and use -support of receiving water.
The second part of the screening process for the selected high priority area is conducting a dry
weather field screening of all outfalls that meet the above criteria to detect illegal discharges.
The dry weather field screening shall not be conducted during or within 72 hours following a
rain event of 0.1 inches or greater. In residential areas, it is recommended to conduct the field
screening either before 9:00 am or after 5:00 pm, since these are the hours that citizens are
most likely to be home and thus any illegal discharges are more likely to be evident.
Figure 3a illustrates the process to be followed for conducting field screening sampling
activities and following up with any findings of dry weather flow. As shown in the figure, if
the field screening shows that an outfall is dry, then the outfall should be checked for
intermittent flow at a later date.
If the field screening shows that an outfall has a dry weather flow, then the City will complete
a screening report for the outfall. The information that should be contained in the screening
report is outlined in Table 3c. Screening reports shall be kept on file for a minimum of five
years. Example screening report forms are provided in Appendix Q.
27

Table 3c: Field Screening Report Ifl#ermaltion
General Information
Sheet Number
Outfall ID Number
Date
Time
Date, Time and Quantity
of Last Rainfall Event
Field Site Description
Location
Type of Outfall
Dominant Watershed Land Use(s)
Visual Observations
Photograph
DepositslStains
Odor
Vegetation Condition
Color
Structural Condition
Clarity
Biological
Floatables
Flow Estimation
Sampling Analysis "
Temperature
Nitrogen-Nitrate/Nitrite
pH
Fluoride or Chlorine
Nitrogen -Ammonia
Total Phosphorus
Ortho-Phosphate
* Analytical monitoring is required only if an obvious source of the dry weather flow cannot
be determined through an investigation of the upstream stormwater collection system.
Outfalls with flow will be screened again within 24 hours for the above parameters. The tests
for ammonia and nitrate/nitrate that are purchased should be sensitive for 0.1 to 10 mg/L.
I"
28 -Ilk

Figure 3a: Field Screening Process
No flow
Screen outfall in high priority area b, Check for signs of intermittent flow
Flow found Flow No flow
found
Inspect and sample flow Outfall OK
Investigate source of flow, considering
r- he following:
• Jurisdiction -wide information collected
• Field investigation of drainage area of
outfall
• Sampling data
• Qualitative observations -- sheen, odor,
turbidity, etc.
Remove illegal discharge
* Checking for intermittent flow includes rechecking outfall at a later date as well as visual
observations for evidence of intermittent flow.
.� Note: Analytical monitoring is required only if an obvious source of the dry weather flow
cannot be determined through an investigation of the upstream stormwater collection system.
29

The purpose of the field screening is to provide clues as to the source of the illegal discharge.
The characterization should be used in conjunction with the jurisdiction -wide information and
a field investigation to identify the source of the illegal discharge. The process of identifying
and removing illegal discharges is discussed in the next section.
XF. Identifying and Removing Illegal Discharges
After the field screening is complete, the City will take measures to identify and remove any .-.
illegal discharges identified. Identifying illegal discharges may require a combination of
office and field work. After the field screening, City staff will consult the jurisdiction -wide
information compiled (see Section 3-D) to obtain information about the land uses, -�
infrastructure, industries, potential sources and types of pollution that exist in the drainage
area of the outfall.
After potential sources have been identified, a systematic field investigation will be planned
that minimizes the amount of resources required to identify the source. Methods that my be
used to identify the source of the discharge include, but are not limited to:
• Site Investigation
• Additional Chemical Analysis (recommend testing for fecal coliform if the ammonia
concentration was found to exceed 1.0 mg/L)
• Flow Monitoring (recommended to use multiple site visits rather than a depth indicator)
• Dye Testing (fluorescent dye is recommended)
Smoke Testing
• Television Inspection
Documentation of the field investigations results will be kept on file for a minimum of five
years with the screening report.
Upon identification of the source of an illegal discharge, the City will use the legal authority
established in its ordinances to have the source removed and/or deal with non-compliance.
In addition to keeping all screening reports on file, the City will maintain a map that includes
the following:
• Points of identified illegal discharges.
• Watershed boundaries of the outfalls where illegal discharges have been identified.
• An accompanying table that summarizes the illegal discharges that have been identified
that includes location, a description of pollutant(s) identified, and removal status.
30

3-G. Preventing Discharges and Establishing a Hotline
The City of Rocky Mount has established a Stormwater Hotline [phone]) that is
publicized through the City web page, the news media, bill inserts and other media. The
hotline is publicized as a means for citizens and stormwater customers to report flooding,
clogged pipes and other drainage problems as well as illegal dumping, spills and illicit
discharges. After hours calls for emergencies such as toxic spills will be referred to the Police
Department for relay of dispatch to the proper department.
In addition to the Stomwater Hotline, the City will implement a public education program to
inform businesses and residents about what types of discharges should not go to the
stormwater collection system. The education program will be tailored to be appropriate to the
intended audience and will include contacts to likely sources of illegal discharges. Some of
—• these sources include automotive sales, rental, repair and detailing establishments, lawn care
companies, cleaners and certain types of contractors.
3-H. Implementation Schedule
Implementation Schedule and Annual Reporting Requirements
Year
By August 2004
Implementation Requirements
Establish legal authority to address
illegal discharges
Annual Report Requirements
Submit report identifying
established legal authority to meet
requirements.
By October 2006
Collect jurisdiction -wide
Report on completion of
information.
jurisdiction -wide information
• Select nigh priority area for
collection.
additional screening.
. Submit map of high priority areas
• Initiate illegal discharge hotline.
and reason for selection.
• Report on initiation of illegal
discharge hotline.
Each subsequent
• Complete mapping and field
Submit map of stormwater
year after 2006
screening for high priority area.
collection system in high priority
• Select next high priority area.
area upon request by DWQ.
• Identify and remove Illegal
Document illegal discharges
discharges as encountered.
found and resulting action.
• Continue operating illegal
Report on hotline usage and
discharge hotline.
actions taken.
• Submit map of next high priority
area and reason for selection.
flu

3-I. References
Debo, Thomas N. and Reese, Andrew 3., Municipal Stormwater Management, CRC Press,
Inc. 1995
U.S. Environmental Protection Agency (EPA). 1992. Manual of Practice — Identification of
Illicit Connections. EPA 833/R-90-100
U.S. Environmental Protection Agency (EPA). 1993. Investigation of Inappropriate Pollutant
Entries into Storm Drainage Systems — A User's Guide. EPA 600/R-92-238.
U.S. Environmental Protection Agency (EPA). 1991. Guidance Manual for the Preparation of
Part 1 of the NPDES Permit Applications for Discharges from Municipal Separate Storm
Sewer Systems. EPA 505/8-91-003A. --
32

4. Retrofit Locations
4 A. Requirements in the Rule
The rule requires that all affected local governments establish a program to identify and
prioritize places within existing developed areas that are suitable for retrofits.
4 B. Approach for Meeting the Requirements
Retrofit opportunities will be considered acceptable if all of the following conditions have
been investigated:
• The retrofit, if implemented, clearly has the potential to reduce nitrogen or phosphorus
loading to the receiving water.
• The watershed is clearly contributing nitrogen or phosphorus loading above background
levels.
-- • The landowner where the retrofit is proposed is willing to have the retrofit installed on his
property. Securing the landowner's cooperation is one of the most important tasks for the
local government, as this is often the most difficult aspect of implementing a retrofit.
• There is adequate space and access for the retrofit.
• It is technically practical to install a retrofit at that location.
The minimum number of retrofit opportunities that each local government is required to
.w identify is based on a sliding scale according to the population of the government. For those
communities that are not completely located within the Tar -Pamlico River Basin, the number
of retrofits can be based on the estimated population within the Tar -Pamlico River Basin. The
local government will have to provide the data to support this population. Table 4a shows the
minimum requirements for identifying retrofit opportunities for each affected jurisdiction.
Sites may be carried over to meet the minimum requirements for up to two subsequent years
provided that BMPs/retrofits have not been implemented and the site continues to meet the
criteria above on an annual basis.
33

Table 4a: Minimum Number of Retrofit Opportunities that Each Local Government Must
Identifv on an Annual Basis
Estimated 2001
Minimum Number
Population Category
Local Government
Basin
of Retrofit Sites
Population
to be Identified
Less than 15,000
Tarboro
11,200
1
Oxford
8,500
Washington
9,700
Between 15,000 and 30,000
Edgecombe County
22,400
2
Henderson
16,300*
Nash County
29,000
Between 30,000 and 60,000
Beaufort County
30,600
3
Franklin County
38,500
Greenville
41,700
Pitt County
31,800
Rocky Mount
56,000
Over 60,000
4
* Represents total municipal population; portion within Basin not determined.
4-C. Data Collection and Notification
..
Each retrofit opportunity that is identified shall be accompanied by information to describe the
location of the retrofit, the type of retrofit being proposed, the property owner, as well as basic
information about the watershed and the receiving water. Table 4b shows a suggested format
for presenting this information for each retrofit opportunity.
The tables shall be submitted to the Division of Water Quality on October 30 of each year
beginning in the year 2005 as part of the annual report.
The Division of Water Quality will take the responsibility for posting these retrofit
opportunities on its Web Page and also for notifying, at a minimum, the following
organizations of the opportunities for retrofitting within existing developed areas:
❑ Clean Water Management Trust Fund
❑ N.C. State University Cooperative Extension Service
❑ Kerr -Tar Regional Council of Governments
❑ Upper Coastal Plain Council of Governments
❑ Mid -East Commission -.
❑ Environmental programs at NCSU, Duke University, UNC, ECU and others
❑ N.C. Sea Grant
❑ USDA -- Natural Resources Conservation Service --
❑ Tar -Pamlico Basin Association
❑ N.C. Wetlands Restoration Program
34

4-D. Mapping Requirements
The City will provide maps that show the locations of retrofit opportunities. Mapping may be
accomplished by using computers or with existing hard copy maps. The scale of the map
should be large enough to adequately identify the following required parameters:
Drainage area to retrofit opportunity site.
• Land uses within the drainage area.
• Location of retrofit opportunity.
• Property boundaries in the vicinity of the retrofit opportunity.
._. • Significant hydrography (as depicted on U.S.G.S. topographic maps and USDA-NRCS
Soil Survey maps).
• Roads.
• Environmentally sensitive areas (steep slopes, wetlands, riparian buffers, endangered/
threatened species habitat — where available).
• Publicly owned parks, recreational areas, and other open lands.
W

Tahie 4h- Retrofit Onoortunitv Table
Location description, including directions
from a major highway
Type and description of retrofit opportunity
Current property owner
Is the property owner willing to cooperate?
Land area available for retrofit (sq. ft)
Accessibility to retrofit site
Drainage area size (acres)
Land use in drainage area (percent of
each type of land use)
Average slope in drainage area (%)
Environmentally sensitive areas in
drainage area (steep slopes, wetlands,
riparian buffers, endangered/ threatened
species habitat)
Approximate annual nitrogen and
phosphorus loading from drainage area
Ibs/acre) ear *
Potential nitrogen reduction (Ibs/ac/yr)*
Potential phosphorus reduction (Ibs/ac/yr)*
Estimated cost of retrofit
Receiving water
DWQ classification of receiving water
Use support rating for receiving water
Other important information
* q, innaetad mPthndoloav- Use the methodoloav
provided in Appendix hl to compute nitrogen export
P.
from the drainage area based on the amount of impervious surface, landscaped area and forested w
area in the watershed.
36

S. Public Education
5 A. Requirements in the Rule
The Tar -Pamlico Stormwater Rule requires each of the affected jurisdictions in the Tar -
Pamlico River Basin to develop a locally administered environmental education program to
address nitrogen & phosphorous loading issues with the public and developers, and to
address peak stormwater flow issues with developers.
5-B. Public Education Action Report and PIan
The ultimate goal of the public education program is to educate the general public, affected
county and municipal staff, the development community, and elected officials. In order to
meet this goal, the City is required to develop a Public Education Action Report and Plan.
The Action Report and Plan will outline the proposed education activities for the upcoming
year, identifying target audiences and anticipated and actual costs of the program. The City
will submit an annual Action Report and Plan to DWQ for approval in its October annual
report each year. A copy of the proposed 2004-05 Action Report and Plan is included in
Appendix S.
The Action Report and Plan will consist of various types of activities. Innovative public
education activities not included in this list are encouraged by DWQ, and will be considered
for approval by DWQ on a case -by -case basis. All activities must be designed to raise
awareness and educate the audience about water quality, nonpoint source pollution, and the
effects of everyday activities on water quality and nutrient loading.
The Action PIan in Appendix S identifies point values for each type of education activity
that may be contemplated by the City. All affected local governments required to develop a
plan are must conduct activities that sum to at least 15 points each year. Ongoing activities,
such as continuing programs for pet waste or storm drain marking, will receive credit for
each year that they are continued.
During the first year of program implementation, affected communities are required to
conduct two (2) technicaI workshops. One shall be designed to educate local government
officials and staff and the other for the development community, including: engineers,
developers, architects, contractors, surveyors, planners, and realtors. These two workshops
will receive point credit toward the annual total. During subsequent years, technical
workshops are considered an optional activity. Communities are encouraged to work jointly
to develop and conduct the workshops, if feasible. .
37

6. Reporting Requirements
Annual Tar -Pamlico River Basin stormwater program reports must be submitted to the
Division of Water Quality by October 30 of each year beginning in 2005. All reports shall
contain the following information.
6-A. New Development Review/Approval
Under the model program for new development review/approval, local governments are —
responsible for submitting the following information as part of the annual reporting
requirement:
• Acres of new development and impervious surface based on plan approvals.
• Acres of new development and impervious surface based on certificates of occupancy.
• Summary of BMPs implemented and use of offsite options.
• Computed baseline and net change in nitrogen and phosphorus export from new
development that year.
• Summary of maintenance activities conducted on BMPs.
• Summary of any BMP failures and how they were handled.
• Summary of results from any applicable jurisdictional review of planning issues.
6-B. Illegal Discharges
Table 6a outlines the annual reporting requirements for illegal discharges.
Table 6a: lmolementation Schedule and Annual Reporting Requirements
Year
implementation Requirements
Annual Report Requirements
By August 2004
• Establish legal authority to
• Submit report identifying
address illegal discharges
established legal authority to
meet requirements.
By October 2006
a Collect jurisdiction -wide
a Report on completion of
information.
jurisdiction -wide information
• Select high priority area for
collection.
additional screening.
0 Submit map of high priority
• Initiate illegal discharge hotline.
areas and reason for selection.
• Report on initiation of illegal
dischar e hotline.
Each subsequent
0 Complete mapping and field
• Submit map of stormwater
year after 2006
screening for high priority area.
collection system in high priority
• Select next high priority area.
area upon request by DWQ.
Identify and remove Illegal
Document illegal discharges
discharges as encountered.
found and resulting action.
• Continue operating illegal
0 Report on hotline usage and
discharge hotline.
actions taken.
• Submit map of next high priority
area and reason for selection.
38

6-C. Retrofit Locations
• Data on each retrofit opportunity (Table 4b or other equivalent format),
• Maps of potential retrofit sites as specified in Section 4-D, and
• The status of any retrofit efforts that have been undertaken within the jurisdiction.
6-D. Public Education
The Report will summarize the next year's Action Plan and evaluate the implementation of
the previous year's Action Plan (if applicable). The report should include goals, activities
completed, realized education program costs, explanation of experienced shortfalls and a
w.
plan as to how the City will address shortfalls.
39

APPENDICES
Tar -Pamlico River Basin:
Stormwater Program
for Nutrient Control
DRAFT
February 13, 2004
_ Revised June 14,2004

Appendices
.. Appendix A
Implementation Schedule and Table of Responsibilities______________________2
Appendix B
Local Program Submittal Checklist .._______4
-----------------------------------------------
Appendix C
15A NCAC 2B .0258 Tar -Pamlico River Basin Nutrient Sensitive
Waters Management Strategy- Basinwide Stormwater Requirements.5
Appendix D
The Nitrogen Cycle_______________
Appendix E
Sources of Nitrogen in Developed Areas ----------------------------------------------
12
Appendix F
The Phosphorus Cycle........................................................................23
^` Appendix G
Sources of Phosphorus in Developed Areas ...............24
.......................
Appendix H
Export Calculation Worksheets and Supporting Information ..............
25
Appendix I
Summary of BMP Literature Studies
44
^, Appendix J
Computing the Intensity -Duration Variable for the One -Year Storm
in Wake, Wilson, and Craven Counties.............................................67
Appendix K
Land Use Planning and Design Techniques .........................................
70
Appendix L
Ordinance Establishing Stormwater
Nutrient Management Requirements for New Development___ -----------
75
Appendix M
Stormwater Facility Maintenance Agreement....................................98
i Appendix N
Conservation Easement
Appendix O
Low Maintenance Conservation Easement -----------------------------------------
114
Appendix P
Ordinance Establishing Legal Authority
for Illegal Discharge Program............................................................123
Appendix Q
Illicit Discharge Screening Report Form___________________________________________132
•— Appendix R
List of Education Resources
133
Appendix S
Public Education Action Report_____________________
138
Appendix T
New Development Annual Report Form _ ________________140
1

Appendix A. Implementation Schedule and
Table pf Responsibilities
The following table lists the various program areas of the City of Rocky Mount Stormwater Program ^
for Nutrient Control and identifies the department responsible for ensuring that the requirements of
the designated program are fulfilled.
Program Area
Responsible Party
City Engineer
Engineering Department
New Development
PO Box 1180
Rocky Mount, NC 27802
252-972-1120
Asst. Public Works Director
Public Works Department
Illegal Discharge Elimination
PO Box 1180
Rocky Mount, NC 27802
252-972-1520
Retrofit Locations
City Engineer
Public Education
Asst, Public Works Director
Reporting Requirements
Asst. Public Works Director
In July of 2003 the City of Rocky Mount implemented a Stormwater Utility to help support the
requirements of this program as well as the requirements of NPDES Phase II. The Utility is
administered through the Public Works Department and provides new staff and financial resources
dedicated to implementation of a comprehensives stormwater management program. The program
includes system master planning, public outreach initiatives, new development regulation, an illegal
discharge elimination program and increased investment in system maintenance and capital
construction.
Implementation Schedule
.. ::
2004 1
2005
2006
J
F
M
A
M
J
!
A
S
o
N
D
1
2
3
4
1
2
3
4
Resolution of Support
"JC
Update Design Manual
Engineers/Developers Workshop
vx
Ordinance Adoption
Public Educalionlputreach
":
yµp�
M� p
y��/c
+�[\k
X'.n
Stormwater Hotline
- x_`'
`" k
°7
Mapping
Illegal Discharge Screening'
j�,"
_ it
:iC
x z
::sx
x�
: ii
_ j�
x f
x
X
,7c
x;
Retrofit Locations
�x";'•M.
Annual Report
r.
P

-- New Development Permitting: New development will continue to be permitted under existing
processes but will be subject to new stormwater management standards upon adoption of the
Nutrient Management Requirements. Copies of the proposed plan and ordinances will be made
�- available to the development community concurrent with consideration of the plan by City Council.

Appendix B. Local Program Submittal
Checklist
Program to Assure Long -Term Maintenance of BMPs
Q
0
Approach for Considering Land Use Planning/Design Techniques
0
Description of Proposed Regional/Jurisdiction-Wide Approach (not required)
III al Discharges Program Components
Approach to Collecting Jurisdiction -Wide Information
Q
Approach to Mapping and Field Screening in High Priority Areas
Removing Illegal Discharges
Q
Program for Identifying and
Illegal Discharges and Establishing a Hotline
Program for Preventing
Description of Proposed Regional/Jurisdiction-Wide Approach (not required)
Retrofit Program Components
Approach to Data Collection and Notification
Approach for Complying With Mapping Requirements
Description of Proposed Regional/Jurisdiction-Wide Approach (not required) CHI
Public Education Program Components
Description of Public Education Program
Description of Proposed Regional/Jurisdiction-Wide Approach (not required)
Reporting Requirements
Description of Proposed Report Contents/Fonnat 0
Description of Proposed Regional/Jurisdiction-Wide Approach (not required)
..%
4

Appendix C. 15A NCAC 2B .0258 Tar -
Pamlico River Basin - Nutrient Sensitive
Waters Management Strategy:
Basinwide Stormwater Requirements
(a) PURPOSE. The purposes of this Rule are as follows.
(1) To achieve and maintain a reduction in nitrogen loading to the Pamlico
estuary from lands in the Tar -Pamlico River Basin on which new development
occurs. The goal of this Rule is to achieve a 30 percent reduction relative to
pre -development levels;
(2) To limit phosphorus loading from these lands to the estuary. The goal of this
Rule is to limit phosphorus loading to pre -development levels;
(3) To provide control for peak stormwater flows from new development lands to
ensure that the nutrient processing functions of existing riparian buffers and
streams are not compromised by channel erosion; and
(4) To minimize, to the greatest extent practicable, nitrogen and phosphorus
loading to the estuary from existing developed areas in the basin.
(b) APPLICABILITY. This Rule shall apply to local governments in the Tar -Pamlico
basin according to the following criteria.
(1) This Rule shall apply to the following municipal areas:
(A) Greenville
(B) Henderson
^„ (C) Oxford
(D) Rocky Mount
(E) Tarboro
(F) Washington
(2) This Rule shall apply to the following counties:
(A) Beaufort
(B) Edgecombe
(C) Franklin
(D) Nash
(E) Pitt
(3) The Environmental Management Commission may designate additional local
governments as subject to this Rule by amending this Rule based on the
-- potential of those jurisdictions to contribute significant nutrient loads to the
Tar -Pamlico River. At a minimum, the Commission shall review the need for
additional designations as part of the Basinwide process for the Tar -Pamlico
River Basin. The Commission shall consider, at a minimum, the following
criteria related to local governments: population within the basin, population
density, past and projected growth rates, proximity to the estuary, and the
— designation status of municipalities within candidate counties.

(c) REQUIREMENTS. All local governments subject to this Rule shall develop
stormwater management programs for submission to and approval by the Commission
according to the following minimum standards:
(1) A requirement that developers submit a stormwater management plan for all
new developments proposed within their jurisdictions. These stormwater
plans shall not be approved by the subject local governments unless the
following criteria are met:
(A) The nitrogen load contributed by the proposed new development
activity shall not exceed 70 percent of the average nitrogen load
contributed by the non -urban areas in the Tar -Pamlico River basin
based on land use data and nitrogen export research data. Based on
1995 land use data and available research, the nitrogen load value shall
be 4.0 pounds per acre per year;
(B) The phosphorus load contributed by the proposed new development
activity shall not exceed the average phosphorus load contributed by
the non -urban areas in the Tar -Pamlico River basin based on land use
data and phosphorus export research data. Based on 1995 land use
data and available research, the phosphorus load value shall be 0.4
pounds per acre per year;
(C) The new development shall not cause erosion of surface water
conveyances. At a minimum, the new development shall not result in a
a net increase in peak flow leaving the site from pre -development
conditions for the 1-year, 24-hour storm event; and
(D) Developers shall have the option of partially offsetting their nitrogen
and phosphorus loads by providing treatment of off -site developed
areas. The off -site area must drain to the same classified surface
water, as defined in the Schedule of Classifications, 15A NCAC 2B
.0316, that the development site drains to most directly. The developer
must provide legal assurance of the dedicated use of the off -site area
for the purposes described here, including achievement of specified
nutrient load reductions and provision for regular operation and
maintenance activities, in perpetuity. The legal assurance shall include
an instrument, such as a conservation easement, that maintains this
restriction upon change of ownership or modification of the off -site
property. Before using off -site treatment, the new development must _.
attain a maximum nitrogen export of six pounds/acre/year for
residential development and 10 pounds/acre/year for commercial or
industrial development.
(2) A public education program to inform citizens of how to reduce nutrient
pollution and to inform developers about the nutrient and flow control
requirements set forth in Part (c)(1).
(3) A mapping program that includes major components of the municipal separate
storm sewer system, waters of the State, land use types, and location of
sanitary sewers. --
(4) A program to identify and remove illegal discharges.
6

(5) A program to identify and prioritize opportunities to achieve nutrient
reductions from existing developed areas.
(6) A program to ensure maintenance of BMPs implemented as a result of the
provisions in Subparagraphs (c)(1) and (c)(5 ).
(7) A program to ensure enforcement and compliance with the provisions in
Subparagraph (c)(1).
(8) Local governments may include regional or jurisdiction -wide strategies within
their stormwater programs as alternative means of achieving partial nutrient
" removal or flow control. At a minimum, such strategies shall include
demonstration that any proposed measures will not contribute to degradation
of surface water quality, degradation of aquatic or wetland habitat or biota, or
destabilization of conveyance structure of involved surface waters. Such local
governments shall also be responsible for including appropriate supporting
information to quantify nutrient and flow reductions provided by these
measures and describing the administrative process for implementing such
strategies.
(d) TIMEFRAME FOR IMPLEMENTATION. The timeframe for implementing the
stormwater management program shall be as follows:
(1) Within 12 months of the effective date of this Rule, the Division shall submit
a model local stormwater program that embodies the minimum criteria
described in Paragraph (c) of this Rule to the Commission for approval. The
Division shall work in cooperation with subject local governments in
,^ developing this model program.
(2) Within 12 months of the Commission's approval of the model local
stormwater program or within 12 months of a local government's later
designation pursuant to Subparagraph (b)(3), subject local governments shall
submit their local stormwater management programs to the Commission for
review and approval. These local programs shall meet or exceed the
requirements in Paragraph (c) of this Rule.
(3) Within 18 months of the Commission's approval of the model local
stormwater program or within 18 months of a local government's later
... designation pursuant to Subparagraph (b)(3), subject local governments shall
adopt and implement their approved local stormwater management program.
(4) Local governments administering a stormwater management program shall
•• submit annual reports to the Division documenting their progress and net
changes to nitrogen load by October 30 of each year.
(e) COMPLIANCE. A local government that fails to submit an acceptable local
-- stormwater management program within the timeframe established in this Rule or fails to
implement an approved program shall be in violation of this Rule. In this case, the
stormwater management requirements for its jurisdiction shall be administered through
the NPDES municipal stormwater permitting program per 15A NCAC 2H .0126. Any
local government that is subject to an NPDES municipal stormwater permit pursuant to
this Rule shall:
• ^ (1) Develop and implement comprehensive stormwater management program to
reduce nutrients from both existing and new development. This stormwater
7

management program shall meet the requirements of Paragraph (c) of this
Rule for new and existing development.
(2) Be subject to the NPDES permit for at least one permitting cycle (five years)
before it is eligible to submit a local stormwater management program to the
Commission for consideration and approval.
History Note: Authority G.S. 143-214.1; 143-214.7; 143-215.3(a)(1); 143-215.6A; 143-
215.6B; 143-215.6C; 143-282(d);
Eff. April 1, 2001. ^
^
8

Appendix D. The Nitrogen Cycle
Forms of Nitrogen
Although nitrogen is the major pollutant of concern for the Tar -Pamlico River Estuary, it
is also a nutrient that is essential for life. The majority of nitrogen on the planet exists as
N2 gas in the atmosphere. In fact, 78% of the volume of the air we breathe is nitrogen.
Nitrogen is not a natural constituent of rocks or minerals.
The N2 molecule has a triple bond, which is the most stable bond
N _ N known to science. Plants obtain all of the oxygen and carbon they need
1 from the air. However, it is very difficult for a plant to obtain nitrogen
from the atmosphere because N2 gas is so non -reactive.
Very special circumstances are required to break the triple bond in N2 gas and to convert
the nitrogen into forms that most plants can use, as described in the next section. The
majority of plants obtain nitrogen from the soil as either nitrate (NO3) or ammonium
(NH4).
Once in the plant, ammonium can be used directly but nitrate is transformed to the
ammonium form using energy derived from photosynthesis. The plant uses nitrogen to
form proteins that act primarily to control plant growth processes. A good supply of
nitrogen is associated with vigorous growth and a deep green color. Plants deficient in
nitrogen become stunted and yellow in appearance.
Nitrogen in plant -available forms is generally scarce under natural conditions. In other
-� words, under natural conditions, nitrogen is a limiting growth factor. Only recently have
humans upset the balance by the addition of nitrogen fertilizers and NOx emissions and
by artificially concentrating nitrogen sources such as human and livestock wastes.
Nitrogen is classified as either inorganic or organic nitrogen. At any given time, most of
the nitrogen in the soil is in the organic form. Inorganic nitrogen compounds are unstable
-� and nitrogen is constantly returning to the atmosphere in gaseous forms.
Inorganic Forms of Nitrogen
N2: Inert nitrogen gas found in the atmosphere
NO2: Nitrous oxides, is found in the atmosphere and is a component of
automobile exhaust and industrial processes
NH3: Ammonia is a volatile gas and often is lost from soil applied ammonium
fertilizer and animal manure into the atmosphere
NH4+: Ammonium, is a positively charge cation found in the soil
NO2-: Nitrite, is a negatively charge anion found in the soil
E

NO3-: Nitrate, is a negatively charge anion found in the soil and at times in the
atmosphere
Organic Forms of Nitrogen
Organic sources of nitrogen include proteins and other complex compounds found -�
in living, dead, or decomposing plants and animals.
The Nitrogen Cycle
The conversion of N2 to N compounds and from nitrogen compounds back to N2 is the
nitrogen cycle. It has been estimated that it takes from 44 to 220 million years for all
nitrogen to pass through the cycle. In 1982, it was estimated that human activities have
caused an imbalance in the nitrogen cycle that causes an accumulation of nine million
metric tons per year. This accumulated nitrogen can cause pollution problems.
Figure Cl shows a simplified nitrogen cycle in an undisturbed, forested area. In an urban
area, human activities add sources of nitrogen other than the ones shown here. Modified
nitrogen cycles are shown in Chapter 4 for each of the appropriate nitrogen sources.
Losses of Nitrogen
Nitrogen can be easily lost into the environment by various pathways. Those pathways
include volatilization, leaching and runoff, and crop removal. ^
Volatilization, or the gaseous loss of ammonia, may occur under certain conditions with
ammonia fertilizers. In situations where the soil is pH alkaline, or where limestone has
recently been applied on acid soils, applications of ammonium fertilizer may result in the
transformation of ammonium (NH4) to ammonia (NH3) which may be lost to the
atmosphere. Urea fertilizers are particularly likely to volatilize. This situation can be
avoided by incorporating these fertilizers into the soil in the case of soils with alkaline pH
or waiting at least one month after limestone applications to surface apply ammonium
fertilizers.
Leaching and Runoff are other important sources of nitrogen loss. Leaching occurs
when inorganic forms of nitrogen, particularly nitrite (NO2) and nitrate (NO3) are
solubilized and carried with water through the soil profile or with surface waters. Factors
that contribute to nitrite and nitrate leaching or runoff include the following:
• Heavy, one-time applications of N fertilizers on sandy textured soils.
• Over applications of manure or sludge to land.
• Improperly timed applications of N fertilizer.
• Poorly designed or nonexistent soil conservation measures.
• Periods of exceptionally heavy rain.
10

-lure ct. Simpnttea
X.
Flow to
Volatization Hary owing Denitrification Surface Water
:F
Ammonia
(NH3)
Plant Uptake
Ammonium (N 44+) --► Nitrite (NO2-)
► Nitrate (NO3-)
Soil Organic
f
Matter
Leaching to
Groundwater
Harvest and Mowing are very important ways that nitrogen is lost. If crops are
harvested and removed, there is a net loss to the farm's balance sheet for nitrogen.
However, if crop residues or lawn clippings are saved and returned to the soil, some of
the nitrogen will be recycled.
References
National Research Council. 1993. Soil and Water Quality: An Agenda for Agriculture.
National Academy Press. Washington, DC.
NC Cooperative Extension Service. NCSU Nutrient Management Manual. Chapter 3.
Raleigh, NC.
11

Appendix E. Sources of Nitrogen in
Developed Areas
Water quality data from large municipalities in North Carolina clearly show that nitrogen
loading is a problem in streams with entirely urban watersheds. Therefore, it is necessary
and equitable for urban areas to address their nonpoint sources of nitrogen. An additional
benefit of implementing practices to control nitrogen is that these practices are effective
for a wide range of other pollutants, such as sediment, heavy metals, oil and grease, and
bacteria.
Based on the present research, it appears that there are four major sources of nitrogen
contributed by urban areas. These sources are:
• Atmospheric deposition
• Fertilizer
• Human waste
• Animal waste
Atmospheric Deposition
Scientific evidence shows that atmospheric deposition is a significant source of nitrogen
loading in urban areas. In fact, researchers in the Metropolitan Washington area believe
that have shown that washoff of nitrate deposited on impervious surfaces from the
atmosphere account for the majority of nitrogen in urban streams (MWCOG 1983).
Although atmospheric deposition occurs on all types of land areas, nitrogen deposited on
urban areas is more likely to enter surface waters than nitrogen deposited on forests and
farms. Urban areas contain impervious surfaces such as roofs, driveways and roads that
quickly channel runoff and associated pollutants directly to surface waters with no --
opportunity for interception or uptake. Impervious surfaces that are drained by storm
sewer systems generally have pollutants carried directly into surface waters. Urban roads
also have a greater number of local emissions sources, resulting in greater deposition on -�
them than on the landscape as a whole. Figure D 1 illustrates nitrogen pathways for
impervious areas drained by curb and gutter.
Another reason why atmospheric deposition is a more significant source of nitrogen in
urban areas is that urban soils are often heavily compacted and thus can function almost
as an impervious surface themselves. Information on how to maintain urban soils and
lawns is offered in the next section.
12

Figure D1. Nitrogen Pathways for Impervious Areas Drained by Curb and Gutter
Impervious areas associated with transportation, such as driveways, roads, and parking
lots are usually greater sources of nitrogen than rooftops. Rooftop runoff, particularly in
residential areas, is usually spread out over pervious yards that are not directly connected
to the storm drain system. During smaller storms, rooftop runoff can infiltrate into the
soil, and less runoff and pollutants are delivered to the stream.
Scientists from the Center for Watershed Protection estimate that the annual TN load
... from a parking lot is 15.4 lb/ac/yr (Schueler 1995)_ It is likely that roads with curb and
gutter have similar export coefficients. According to recent DWQ estimates, the overall
annual TN load from urban areas is 6.7 lb/ac/yr (1996). DWQ's estimated annual TN
load includes not only contributions from parking lots and roads, but also nitrogen from
construction areas, onsite wastewater treatment, and solid waste disposal (DWQ 1996).
The large difference between the estimated loads suggests that transportation -related
�- imperviousness is a significant source of nitrogen.
There is also evidence that nitrogen loads increase as average daily traffic volume
r- increases. Runoff monitoring by the Federal Highway Administration (1990) indicates
that highways with average daily traffic volume below 30,000 were found to have a 40%
lower concentration of nitrate-N than highways with average daily traffic volume
exceeding 30,000,
In summary, the available data indicate that:
.- 13

• The transport of atmospheric nitrogen from land to surface waters is a major
contributor of nitrogen to urban streams, and
• Reducing transport -related imperviousness in urban areas is likely to play a important
role in reducing the deposited nitrogen that moves from urban land to surface waters.
• Minimizing the use of curb and gutter with storm sewer will also reduce the deposited
nitrogen that moves from urban land to surface waters, and
• Reducing vehicle use in urban areas will reduce the amount of deposited nitrate
nitrogen that could possibly be transported to surface waters.
In addition to reducing the amount of nitrogen moving into surface waters, reducing
transportation -related imperviousness, minimizing curb and gutter, and reducing vehicle
use all save money. For example, the cost of providing residential infrastructure such as
roads, sidewalks, driveways, and parking spaces, generally constitutes about half of the
cost of residential subdivision (Schueler 1995). -�
Reducing road widths, parking lot sizes, and the use of curb and gutter are important
steps to reduce the contribution of nitrogen from atmospheric deposition. In addition,
these measures will reduce loadings of many other pollutants, including phosphorous,
bacteria, oxygen -demanding substances, and heavy metals. The next chapter on new
approaches for planning development describes steps that can be taken on a larger scale
to reduce overall impervious area.
Fern lizers
Well -managed lawns and landscaped areas help protect water quality in urban areas by
reducing soil erosion, moderating air temperatures, and filtering pollutants. However, the
fertilizers used to maintain these natural areas can pollute urban waters. An important
component of improving fertilizer and pesticide use in urban areas is public awareness
and education.
Studies suggest that a large number of lawn acres are regularly fertilized without
determining the need for nutrient addition. A study found that 79% of Virginia
homeowners use fertilizers, but less than 20% of them had their soil tested (Aveni 1994).
This study found that product labels are the number one information source for
homeowners, while the Cooperative Extension Service ranked last. While all labels
indicate how many square feet the label should cover, each takes a different approach on
how often the product should be applied. Most label instructions do not mention soil
testing.
The nitrogen cycle of fertilizer used on urban lawns is diagrammed in Figure D2.
^
14

Considering privately and publicly managed lawns, Schueler estimates that about a third
of all vegetated areas in the urban landscape can be classified as "high input," meaning
that they receive high rates of irrigation and fertilizer application (1995).
Based on studies by the Center for Watershed Protection (Barth 1995):
• homeowners fertilizing their own Iawns apply 44-261 pounds/acre/year of nitrogen
• home lawn companies apply 194-258 pounds/acre/year of nitrogen.
Although many homeowners are applying fertilizers with incomplete information, lawn
care companies appear to be applying an equal or greater amount of fertilizer. Lawn care
companies usually offer service plans that consist of five or more visits per year. Unless
a customer specifically requests a soil test or a special application rate, most lawn
companies give every lawn serviced the same rate of fertilization (Morton 1988).
The travel distance between lawns and impervious areas can be short. Lawns with
compacted soil, bare spots, steep slopes, and channelized areas have increased flow of
fertilizer off the lawn. Leaching can also be a significant source of nitrogen in areas with
sandy soils where lawns are overwatered and overfertilized (Cohen et al. 1990). In areas
where soils are highly compacted, fertilizer can run off lawns easily. Also, lawns in
urban areas are frequently interlaced with driveways, roads, and parking lots, which
increase the chance for fertilizer to enter into storm sewers.
r.,
-� 15

A review of three nitrate -leaching studies by turfgrass researchers generally shows that
grass, when managed properly, can retain nitrogen fertilizer at the soil surface or within
the root zone and thus prevent soluble nitrates from percolating downward into the ^
environment. All soils were sandy or silty loam. The results of the study are given in
Table D 1. This research strongly suggests that efforts to educate homeowners about lawn
care should stress the critical connection between fertilization and overwatering. The
concept that careless watering can flush nitrogen throughout the soil and away from the
grass should be strongly emphasized on both economic and environmental grounds.
^
Another important factor that affects fertilizer use is soils. Development usually involves
grading the entire site, removing topsoil, erosion during construction, compaction by
heavy equipment, and filling of depressions. Thus, urban soils tend to be highly
compacted, poor in structure, and low in permeability. As a result, urban areas often
produce more runoff than before they were disturbed and thus have more potential to lose
fertilizer. A good lawn care program should also address soil building. +`
Some management strategies that would contribute to a reduction in urban nitrogen from
fertilizer use are:
• Use fertilizers that are composed of slow -release sources of nitrogen. Products
containing slow -release sources of nitrogen are usually called one or more of the
following terms: water -insoluble, slow -release, controlled -release, or slowly -
available water soluble.
• Lightly water after fertilizer application to allow penetration and reduce the potential
for runoff. --
• Use drop (gravity) type spreaders rather than centrifugal (rotary) type spreaders so
that fertilizer will not be deposited on impervious surfaces.
• Aerate lawns to reduce surface runoff. Also, aeration results in a healthier lawn that
does not require as many nutrient inputs. Aerating the soil can reduce the potential �-
for nitrogen export when the soil is compacted or the lawn is on a slope or in a natural
drainage area.
• Select the appropriate grass species to reduce the need to add nitrogen to the lawn.
• Water lawns only when they need it. When lawns are very thirsty, grass will lie flat
and leave footprints when walked on, shrubs will droop or drop leaves and look
wilted. Watering less often actually promotes deeper, more tolerant root systems
(Alliance for the Chesapeake Bay 1994).
• Do not fill fertilizer applicators over a hard surface. Make sure that the spreader is
off when passing over driveway, sidewalk, patio, etc. Clean up any spills
immediately.
16

• Expansive lawn areas can be replace with equally attractive, efficient landscape
alternatives, such as appropriate shrubs or ground covers that require less
maintenance (Alliance for the Chesapeake Bay 1994).
• Involve the public and golf community in decisions that affect water quality. Perhaps
they would be willing to accept a few brown patches in exchange for knowing that
the course is not harming water quality.
Table D1. Nitrate Levels in Soil Water Depending on Turf Management Strategies
(from Schueler 19941
Grass
Irrigation
Management
N
N
Researcher
type
applied
conc.
(lbs/ac/y
(mg/1)
r
Tall
not watered
Clippings
none
0.33
Gross et al.
Fescue/
removed
1990
Bluegrass
Maryland
Bluegrass
overwatered
Clippings left
none
0.36
Morton et al.
1988
Rhode Island
Bluegrass
slightly
Clippings left
none
0.51
Morton et al.
watered
1988
Rhode Island
Tall
not watered
Granular fert.
196
0.85
Gross et al.
Fescue/
Clippings
1990
Bluegrass
removed
Ma land
Bluegrass
slightly
Clippings left
86
0.87
Morton et al.
watered
1988
Rhode Island
Tall
not watered
Liquid fert.
196
1.02
Gross et al.
Fescue/
Clippings
1990
Bluegrass
removed
Ma land
Kentucky
watered
Seeded
194
1.09
Geron et al.
bluegrass
clippings left
1993
Ohio
Bluegrass
slightly
Clippings left
217
1.24
Morton et al.
watered
1988
Rhode Island
Bluegrass
overwatered
Clippings left
86
1.77
Morton et al.
1988
Rhode Island
Kentucky
watered
slow release
194
1.84
Geron et al.
bluegrass
clippings left
1993
Ohio
Kentucky
watered
early season 1
194
1 2.27
1 Geron et al.
,. 17

m"
bluegrass
fert.
1993
Clippings left
Ohio
Kentucky
watered
late season
194
2.30
Geron et al.
bluegrass
fert.
1993
Clippings left
Ohio
Kentucky
watered
fast release
194
2.74
Geron et al.
bluegrass
clippings left
1993
Ohio
Kentucky
watered
Sodded
194
3.50
Geron et al.
bluegrass
clippings left
1993
Ohio
Bluegrass
overwatered
Clippings left
217
4.02
Morton et al.
1988
Rhode Island
Human Waste
Conventional septic systems are comprised of a septic tank, a distribution system, and a
soil absorption system. In the septic tank, anaerobic bacteria digest organic matter, solids
settle to the bottom, and low -density compounds such as oil and grease float to the water
surface. Partially -treated wastewater then leaves the septic tank and enters the
distribution box, where it is discharged into the soil absorption systems, also know as the
drainage field.
In the drainage field, effluent percolates through the soil and remaining pollutants --
nutrients, suspended solids, bacteria, viruses, and organic/inorganic compounds -- are
removed by filtration, adsorption, and microbial degradation (AGWT 990). The
absorption system consists of a network of perforated pipes located in shallow trenches
covered with backfill. Gravel usually surrounds the piped to encourage even distribution
of the effluent into soil.
Even properly functioning septic systems can deliver significant pollutant loads to
groundwater. The most common shortcoming of conventional septic systems is their "~
inability to remove much nitrogen. It is not uncommon for the effluent leaving a typical
system to have a total nitrogen concentration of 40 to 60 mg/l, primarily in the form of
ammonia and organic nitrogen (C13O 1992). Once in the drainage field, organic nitrogen
forms are easily converted into nitrates, which are quite soluble and easily mobilized,
thus increasing the potential for ground and surface water contamination.
Some problems with septic system performance are related to what goes into them.
Household chemicals entering a septic tank can kill organic -consuming bacteria or cause
sludge and scum to be flushed out into the drainfield. Such chemicals can include
various readily available septic system additives, which ironically are advertised as
having the ability to improve system performance. Not only are some household
chemicals detrimental to the septic system itself, but they often reach ground or surface
waters where they cause toxicity problems.
18

r7
Normal amounts of detergents, bleaches, drain cleansers, and toilet bowl deodorizers,
however, can be used without causing harm to bacterial action in the septic tank (AGWT
1990). Properly operating septic systems must be located in a way to ensure both lateral
distance between surface waters and vertical separation to groundwater. Also, drainfield
areas must become larger when soils are not permeable or slopes are steep. Larger
volumes of wastewater require larger drainfields.
Unfortunately, many conventional septic systems have been constructed in areas poorly
suited for their proper operation. Many were installed before the need for separation
distance was understood or because no other wastewater treatment option was available.
Septic systems are suspected of contributing nutrients through subsurface flow.
Malfunctioning systems may increase the nutrient loading beyond the assimilative
capacity of the site soils and vegetation. This may result in excess nutrients being
conveyed to surface waters via groundwater and subsurface flow of infiltrated
stormwater.
While alternative systems have some benefits over conventional septic systems, it is
important to recognize that no system can simply be installed and forgotten. Regular
inspection and maintenance is a necessity. For example, septic tanks should be
periodically pumped out, since solids and sludge tend to accumulate over time. North
Carolina does not require regular pumpouts of conventional septic systems.
Alternative on -site wastewater treatment designs are attractive because of their decreased
reliance on site conditions and their ability to remove pollutants that cannot be removed
by conventional systems. Two options that are particularly promising for nitrogen
removal are recirculating sand filters and constructed wetlands.
Table D2. Pollutant loadings from Septic Systems (Schueler, 1995)
On -site
TN
TSS
BOD
Pathog
Capital
Maint.
wastewater
(%)
{%)
(%)
ens
($/house)
($/house/.
treatment
(Logs)
yr)
system
Conventional
septic system
28
72
45
3.5
$4,500
$70
Recirculating sand
filter
64
90
92
2.9
$3,900
$145
Constructed
90
80
81
4.0
$710
$25
wetlands
To reduce the contribution of nitrogen from septic systems, the following measures are
recommended:
• Homeowners should not use garbage disposals or pour grease down the drain.
19

• Septic systems should be inspected at least once every two years and pumped as
needed (time interval varies with size, use, and operation).
• DWQ, DEH, and local health departments should increase educational efforts for
homeowners to properly operate and maintain septic systems and other on -site
wastewater treatment systems.
• DWQ, DEH, and local health departments should encourage installation of innovative
on -site wastewater treatment systems where they are appropriate and where there is a
commitment to ongoing care and maintenance.
• DWQ, DEH, local health departments, and community groups should increase
surveillance of their local streams to help to identify areas where on -site wastewater
treatment systems are failing.
Another source of nitrogen from human waste is overflowing sanitary sewers. Often,
maintaining infrastructure such as sanitary sewers does not receive a high priority for
funding. Sometimes flow data at wastewater treatment plants indicates that there is a
problem with leaking sewer lines, however it is extremely difficult to pinpoint the sources
of the problem. It is recommended that this issue be addressed in this model program by
educating citizens about how to detect and report an overflowing sanitary sewer line
Animal Waste
Like human wastes, pet wastes also present a concentrated source of nutrients, bacteria,
and oxygen -demanding substances. If these wastes are not disposed of properly, they
often enter storm sewers without any treatment. In fact, some pet owners actually deposit
their pet's waste into storm drains. Figure D3 shows the nitrogen cycle of pet wastes in
urban areas.
9C

To reduce the contribution of nitrogen from pet wastes, the following measures are
recommended:
• Pet owners should use proper disposal methods such as putting waste in the trash
(some landfills prohibit animal wastes) or burying waste in the yard or using a pre-
fabricated pet waste disposal unit (this may relocate the contribution from surface to
subsurface nutrient loading).
• The public should be educated about proper methods of disposing of pet wastes.
• Storm drain stenciling can remind citizens that storm drains go directly to streams.
-� • Local ordinances should require proper pet waste disposal.
References
Alliance for the Chesapeake Bay. Environmentally -Sound Landscape Management.
Richmond, VA.
American Groundwater Trust (AGWT). 1990. Everything you wanted to know about
septic tanks. Dublin, OH.
�„ 21

w-.
Aveni, M. 1994. Homeowner Survey Reveals Lawn Management Practices in Virginia.
Watershed Protection Techniques, 1(2): 85-86. -.
Barth, C. A. 1995. Nutrient Movement from the Lawn to the Stream? Watershed
Protection Techniques. 2(1): 239-246. --
Cohen, S., S. Nickerson, R. Maxey, A Dupuy and J. Senita. 1990. A groundwater
monitoring study of pesticides and nitrates associated with golf courses on Cape --
Cod. Groundwater Monitoring Review. 160-173.
Maryland Cooperative Extension Service, 1995. Green Lawns: The Smart Way. ^�
Annapolis, MD.
Metropolitan Washington Council of Governments. 1983. Urban Runoff in the
Washington Metropolitan Area. Final NURP Report. Department of
Environmental Programs. Washington, D.C. 212 pp.
Morton, T., A. Gold and W. Sullivan. 1988. Influence of Overwatering and Fertilization
of Nitrogen Losses from Urban Lawns. J Environmental Quality. 17: 124-130.
NC Division of Water Quality. July 1996. Neuse River Nutrient Sensitive Waters
(NSW) Strategy. Raleigh, NC. p. 8.
Schueler, T. S. Dec. 1995. Site Planning for Urban Stream Protection. Metropolitan
Washington Council of Governments. Silver Spring, MD 231 pp.
22

Appendix P. The Phosphorus Cycle
(Text to be included at a later date)
23

Appendix G. Sources of Phosphorus in
Developed Areas
(Text to be included at a later date)
24

Appendix H. Export Calculation
Worksheets and Supporting Informa
tion
This appendix contains a set of manual worksheets for estimating nitrogen and
phosphorus export from a development project prior to and following development, and
-- following the installation of best management practices (BMPs) on the development.
The worksheets are followed by supporting information that details the basis for the
design of the worksheets and the values and formulas included in them. Supporting
information on the development of BMP efficiencies is found in Appendix I.
An automated version of the worksheets is also available. Excel files containing the
.� automated version may be downloaded from the Division of Water Quality's Tar -
Pamlico web page at http://h2o.enr.state.nc.us/nps/tgpam.htm. The files may also be
obtained from the City of Rocky Mount web page at http://www.ci.rocky-
mount.ne.us/engineering.
L7
❑ The worksheets in this appendix and the automated version of the worksheets both
contain the following elements:
1. Definitions of Land Use Terms Used in Spreadsheets (I pg.)
2. Residential Worksheet when Footprints are not Shown (1 pg.)
3. Export Calculation Worksheet for Coastal Plain Communities (1 pg.)
4. BMP Removal Calculation Worksheet for Coastal Plain Communities (3 pp.)
5. Export Calculation Worksheet for Piedmont Communities (I pg.)
6. BMP Removal Calculation Worksheet for Piedmont Communities (3 pp.)
❑ The remainder of this appendix is a report describing the development of the nutrient
export model, provided by contractors with North Carolina State University.
25

..
Definitions of Land Use Terms Used in Spreadsheets
Transportation impervious: The portion of the development that is taken up by roads, driveways, parking
areas, wash pads or any other facility designed for vehicular use, maintenance or storage. Transportation
impervious includes areas covered in pavement, gravel, pavers and dirt.
Roof impervious: The portion of the development that consists of roofs of buildings and other structures.
Commercial parking garages shall be considered as transportation impervious.
Managed pervious: The portion of the development that consists of vegetated areas that the landowner could
manage by mowing, clearing, applying fertilizer, etc. Although residential development may include pervious
areas that are initially undisturbed, these areas must be considered as managed pervious (instead of wooded
pervious) unless they have conservation easements or another mechanism to insure they will not be managed.
Also, the land in Zone 2 (the outer 20 feet) of a protected riparian buffer must be considered as managed
pervious area unless it is protected by a conservation mechanism.
Wooded pervious: The portion of the development that consists of forested areas that are permanently
protected by a conservation easement or other binding conservation mechanism. Also, wetlands and the land
in Zone 1 of a protected riparian buffer (the first 30 feet adjacent to a stream) may be considered as wooded
pervious area.
26

A
A.
Residential Worksheet when Footprints are not Shown
Use this worksheet when building footprints are not known to determine the acreage in each of the four categories -
transportation impervious, roof impervious, managed pervious, and wooded pervious - in the development. You will
need these acreages for both the "Export before BMPs" and "Export after BMPs" worksheets. For the "Export after
BMPs" worksheet, you will need to subtract the acreage occupied by BMPs from the managed pervious acreage
produced by this worksheet. Also for the "Export after BMPs " worksheet, if the development contains more than one
catchment, use this worksheet for each catchment.
Project Name:
Date:
By:
Directions:
■ In the two blanks in the box below, enter the average lot size and the percent of the right-of-way that is impervious
within the development.
■ Column (2): Determine the total area of the development that will be in lots and enter it in the top box. Next,
multiply 0.089*total acreage in lots*average lot size °.48 to get transportation impervious - enter this in the second
box. Then, multiply 0.059*total acreage in lots*average lot size-0,48 to get rooftop impervious - enter this in the
third box. In the bottom box (wooded pervious), enter any lot area that is wetlands or permanently protected by a
conservation easement or the Tar -Pamlico buffer rule (enter "0" if there is none). Next, subtract the sum of the
two impervious types and wooded pervious from the total lot area to get managed pervious acreage, the remaining
box. NOTE: If lots are drawn to exclude protected lands that are part of the total development acreage, enter the
acreage of those protected lands as wooded pervious within "Community Areas", column (4).
■ Column (3): Enter the total acreage in the development that will be in right-of-way in the first box. Then,
multiply this value by the percentage of right-of-way that is impervious from the blank below, and enter the result
in the second box (Transportation Impervious in ROW). Subtract this value fi-om the total right-of-way area and
enter this in the third unshaded box (Managed Pervious in ROW).
■ Column (4): Enter the total acreage of any community areas in the development (eg., parks, community centers)
in the top box. In the next four boxes, distribute the total acreage among each type of land use.
' Column (5): Total each row. NOTE: Make sure that the total area in the top box accurately reflects the total area
of the development and that the three lower boxes add up to the top box. If not, there is an error that must be
corrected. You may then want to see if the component acreages in each column add to the top TOTAL value.
Average lot size � ac (Must show building footprints if lot size < 0.13 ac.)
% impervious in right-of-way = %
Type of Land Cover
Lot area
Right-of-way,
Community
Sum of;Columns
(ac)
area (ac)
areas (ac)
(2), (3)a and (4)
TOTAL
Transportation impervious
Roof impervious
Managed pervious
Wooded pervious
27

Piedmont of the Tar -Pamlico River Basin:
Includes Oxford, Henderson, Rocky Mount and Tarboro as well as Franklin, Nash and Edgecombe Counties +"•
Nitrogen and Phosphorus Load Calculation Worksheet (Manual)
Project Name:
Date:
By. Checked By:
Directions (same for pre -development and post -development tables):
■ Column (2): Enter the acres in each land use in all but the bottom two boxes. Add entries to get Total Area of Development
(bottom box). Divide Impervious total (Transport. + R000 by Total Area of Development; enter in Fraction Impervious box.
• Column (3): Compute 0.46 + 8.3*I and enter this number in all unshaded boxes (each box will have the same number in it).
■ Column (4): TN land use coefficients are already entered for each land use.
■ Column (5): In each box except the bottom two, enter the product of Columns (2), (3) and (4) in that row. Determine TN
loading in the next -to -last box by adding the boxes above. Divide the result by the total area of development from column (2) to
determine the TN export coefficient for the bottom box.
■ Column (6): TP land use coefficients are already entered for each land use.
' Column (7): In each box except the bottom two, enter the product of Columns (2), (3) and (6) in that row. Determine TP
loading in the next -to -last box by adding the boxes above. Divide the result by the total area of development from column (2) to
determine the TP export coefficient for the bottom box.
Pre -development:
(1)
(2)
(3)
(4)
(5)
(6)
(7)
Type of Land Cover
Area
S.M. Formula
Average EMC
Column
Average EMC
Column
acres
0.46 + 8.3*
of TN mg[L)
(2)* 3 *(4)
of TP m IL
2 * (3)* 6
Transportation impervious
2.60
0.40
Roof impervious
1.95
0.15
Managed pervious
1.42
0.31
(lawn/landscaped)
Managed pervious
4.23
1.23
(cropland)
Managed pervious
2.04
0.62
(pasture)
Wooded pervious
0.94
0.14
TN Loading
TP Loading
Fraction Impervious (I) =
Ib/ r =
lb/ r) _
TN Exp. Coeff.
TP Exp. Coeff.
Total Area of Development =
lb/ac/ r =
lblae/ r =
Post -development:
(1)
(2)
(3)
(4)
(5)
(6)
(7)
Type of Land Cover
Area
S.M. Formula
Average EMC
Column
Average EMC
Column
acres
0.46 + 8.3*I
of TN m /L
2 * 3 * 4
of TP m /L
2 * 3 * 6)
Transportation impervious
2.60
0.40
Roof impervious
1.95
0.15
Managed pervious
1.42
0.31
Wooded pervious
0.94
0.14
TN Loading
TP Loading
Fraction Impervious (I) =
Ib/ r =
Ib/ r =
Total Area of Development =
TN Exp. Coeff.
TP Exp. Coeff.
Ib/ac/ r =
lb/ael r) =
Note: The nutrient loading goals are 4.0 lb/ac/yr for TN and 0.4 lblac'yr for 1 F. It the post -development nutrient loading is -�
below these levels, then no BMP is necessary. Otherwise, the next worksheet calculates post -development TN and TP
loadings after BMPs are installed.
28

Piedmont of the Tar -Pamlico River Basin:
Includes Oxford, Henderson, Rocky Mount and Tarboro as well as
BMP Removal Calculation Worksheet (Manual)
JProject
Name:
Date:
By:
a
BMP
I
Nutrient
Removal
Efficiencies
1
1
Nash and Edgecombe Counties
Checked By:
TN',.
TP
Wet Detention Pond
25
40
Stormwater Wetland
40
35
Sand Filter
35
45
Bioretention
40
35
Grass Swales-
20
20
Vegetated Filter'Strip wl
30
30
Level Spreader
JDirectionNfor the following pages (same for all catchments in the development):
■ It may be advantageous to split the development into separate catchments to be handled by separate BMPs. This table allows for the
development to be split into up to three catchments, and can be copied for greater than three. Unless runoff into the development from
offsite is routed separately around or through the site, offsite catchment area running in must be included in the acreage values of the
iappropriate land use(s) and treated.
■ Above each table: Enter the catchment acreage in the top blank. Next, based on a comparison of the post -development TN and TP
export coefficients you calculated above to the rule requirements of 4.0 lb/ac/yr TN and 0.4 lb/ac/yr TP, select a BMP or BMPs from
the table above for treating the catchment runoff. Enter the chosen BMP(s) nutrient removal rates in the blanks. If a second BMP is to
J be used in series, determine the TOTAL TN and TP removal rates for the series through the following equation:
removal rate, + removal rate2 - (removal rate, * removal rate2)/100.
■ Column (2): Enter the acres in each land use in the first five boxes. Add to get the total acres of development and enter it in the
seventh box. Divide impervious area by total development area and enter it in the sixth box.
�• Column (3): Compute 0.46 + 8.3*1 (1 = fraction impervious from column 2) and enter this number in all five boxes (each box will
have the same number in it).
■ Column (4): TN land use coefficients are already entered for each land use.
1. Column (5): In each of the first five boxes, multiply the entries for Columns (2), (3) and (4). Determine the pre-BMP TN loading in
the sixth box by adding the first five boxes. Determine the pre-BMP TN export coefficient in the seventh box by dividing the TN load
by the total acreage of the catchment. Determine the post-BMP TN loading in the next -to -last box by the following equation: pre-
JBMP TN loading * (100 - TOTAL TN REMOVAL RATE)/100. Determine the post-BMP export coefficient in the bottom box by
dividing the post-BMP TN loading by the total acreage of the catchment.
■ Column (6): TP land use coefficients are already entered for each land use.
■ Column (7): In each of the first five boxes, multiply the entries for Columns (2), (3) and (6). Determine the pre-BMP TP loading in
Jthe sixth box by adding the first five boxes. Determine the pre-BMP TP export coefficient in the seventh box by dividing the TP load
by the total acreage of the catchment. Determine the post-BMP TP loading in the next -to -last box by the following equation: pre-BMP
TP loading * (100 - TOTAL TP REMOVAL RATE)/100. Determine the post-BMP export coefficient in the bottom box by dividing
II the post-BMP TP loading by the total acreage of the catchment.
29

A•
A-
om

GO
a
;a
.c
as .
:0
cu
m:
G.;
A
.x
e
e
o
Q-

A"
am
•�
o
o
cu
E
N
` M.
Q
ca >
F II
II
11
II
c
F
H
F
O
�
V
C
kn
M
�
rknr
cow
a o
O
O o
` "
c
ra
o p
o
a o
Cd
v3
o � n
x
CC
to co
o z 2
Z
Z II
Z II
v U�
Qwa
as
-0
ti �
1. 000
0
O
U
�V 43
ZS U C C e�1
y�
N �
o
15
II I I II II
� w i
� CU
+
Ea"
w a.
Gn
o
-,vu
en
c
O,r"
a>
L �
o .� p
o
qu
y W
�a..
a
pp
Iwo
°'
Ow
°o
a
°a
c
L
Y+r
ym�
a J
.-
o
x
3
::
Fj
E•-' Ls.. �"
Ei,
L
�'
ti �
cn
OI
W
o
� �
V
IFI
I
I
G
M
M

c
•7
0
�
C G
0.1 �
O,
o pq
N
R
'a O
r a
P. co
G3
.0 ¢i
�3
�O
w
^+
U C
Cr
-0 .0
G Ld
C
z ca-0
w p,
a'
V � N
Cd
O CCV
Y rL
[n ; C
w
to N 0.
O — O
w
ccl
o 0
l�
��•' _U
tw
CU
a
C
C
d
94
u
''' V
....0
H
�

Development of Nutrient Export Model for New
Developments
.in the Tar -Pamlico River Basin
w
A study completed by
NC State University, Biological & Agricultural Engineering
-
Bill Hunt, PE, and Annette Lucas
w
For
The North Carolina Department ofEnvironment & Natural
Resources, Tar -Pamlico Stormwater Group
April 119 2003
35

The Nutrient Export Model for New Developments
The Tar -Pamlico Stormwater Team worked with North Carolina State University to establish a
nutrient export model for new developments. The purpose of this model is to estimate the total
nitrogen {TN} and total phosphorous (FP) loadings from development sites before development,
after development and after installation of BMPs. This model was constructed to allow
developers and local governments to determine if proposed new development projects are in
compliance with the required TN and TP loading limits of 4.0 and 0.4 pounds/acre/year,
respectively.
The experience with nitrogen loading calculations in the Neuse River basin provided the
foundation for the Tax -Pamlico nutrient loading model. The City of Durham made some
significant improvements to the model given in the Neuse Model Stormwater Plan. In addition,
new data on nutrient loadings from various types of development have become available recently.
The Tar -Pamlico Nutrient Loading Model built on this new information.
Application of the Simple Method
Both the Neuse and Tar -Pamlico models are based on the "Simple Method," a model developed
by the Metropolitan Washington Council of Governments during the 1980s. The Simple Method
is extremely useful because it inputs event mean concentrations (EMCs) measured during storm
events in mg/L and converts them to export coefficients in pounds/acre/year.
The Simple Method formula is as follows:
L = P *Pi* R,* C *0.227
Where:
L is the nutrient load in lbs/ac/yr.
P is the average annual rainfall (45 in/yr - Piedmont, 50 in/yr - Coastal Plain).
P; is a correction factor for storms with no runoff (0.9).
R, is the runoff coefficient equal to 0.05 + 0.91 (1 - fraction impervious from 0 to 1).
C is the flow -weighted event mean concentration in lbs/ac/yr.
(The Piedmont includes Oxford, Henderson, Rocky Mount and Tarboro as well as
Franklin, Nash and Edgecombe Counties. The Coastal Plain includes Greenville and
Washington as well as Pitt and Beaufort Counties. This delineation was made based on
rainfall data).
The Simple Method becomes even simpler after realizing that P and P, are known variables. R
can be determined by determining I, the percentage of the development that is impervious. So,
the only real "variable" in the equation is C, the flow -weighted event mean concentration. The
majority of effort in developing the model methodology was spent determining appropriate C
values (more on that later).
36

In order to apply the Simple Method to new developments in the Tar -Pamlico basin, the method
~' was applied to each of the four major land use categories within a development site:
1. Transportation impervious: The portion of the development that is taken up by roads,
driveways, parking areas, wash pads or any other facility designed for vehicular use,
maintenance or storage. Transportation impervious includes areas covered in pavement,
gravel, pavers and dirt.
2. Roof impervious: The portion of the development that consists of roofs of buildings and
other structures that serve single-family homes. Commercial parking garages shall be
considered as transportation impervious.
3. Managed pervious: The portion of the development that consists of vegetated areas that
the landowner could manage by mowing, clearing, applying fertilizer, etc. Although
residential development may include pervious areas that are initially undisturbed, these areas
must be considered as managed pervious (instead of wooded pervious) unless they have
conservation easements or another mechanism to insure they will not be managed. Also, the
land in Zone 2 (the outer 20 feet) of a protected riparian buffer must be considered as
managed pervious area unless it is protected by a conservation mechanism.
4. Wooded pervious: The portion of the development that consists of forested areas that are
permanently protected by a conservation easement or other binding conservation
mechanism. Also, wetlands and the land in Zone 1 of a protected riparian buffer (the first 30
feet adjacent to a stream) may be considered as wooded pervious area.
The Simple Method formulas for each land use category are as follows:
Ltransportation = P * Pi * Rv * Ctransponadon * 0•227
Lroof = P * Pi * R * Croof * 0.227
Lmanaged = P * Pi * P-11 * Cmwaged * 0.227
ooaea = P * P; *R,*Cwoodea 0•227
Figure 1 below is an excerpt from the Piedmont nutrient loading model. The arrows explain
which part of the Simple Method formula each column represents. The Coastal Plain nutrient
loading model is identical to the Piedmont except that the input for rainfall is 50 inches/year in
the Coastal Plain instead of 45 inches/year used in the Piedmont (based on state climatologic
data). This results in a Simple Method formula in column(3) of 0.51 + 9.1*I for the Coastal
.. Plain, where 0.46 + 8.3*I applies to the Piedmont.
37

Figure 1. The Application of the Simple Method to the Nutrient Loading Model
= P * Pi * Rv * 0.227 = C (for TN) = C (for TP) ^'
=4;*0.9*(0.05+0.9*I)*0.227
=0.46+8.3*1
_J L
1 ..
. 2 ..:.
4
5
6
7
Type of Land Cover
Area
(acres)
S.M.
Formula
0.46 + 8.3
Average
EMC of TN
m /L
Column
(2) • (3) •
4
Average
EMC of T
m
Column
(2) • (3) -
6
Transportation impervious
2.60
0.40
Roof impervious
1.95
0.15
Managed. pervious
1.42
0.31
Wooded pervious
0.95
0.14
Fraction Impervious (1) _
(lb/yr) _
(lb/yr)
Total Area of Development
=
:TN Exp.
Coeff.
Iblacl r =
TP Exp.
Coeff.
lblac/ r =
Determining Appropriate EMCs for the Land Uses
The concentrations for the land uses given above were determined based on water quality
monitoring data from Durham, Fayetteville, Raleigh and Chesapeake, VA. These cities were
selected for two reasons:
1. All are required to monitor different types of watersheds under their federal NPDES
(National Pollutant Discharge Elimination System) stormwater permits. All of the data ^,
were collected recently using consistent EPA methodology.
2. All of these cities are geographically close to the Tar -Pamlico river basin and, in a sense,
bracket it.
The data collected by these cities is summarized and graphed below. As Table 1 shows, data
were sorted according to whether the pervious surfaces in the watershed were "managed" or
"unmanaged" (wooded). The decision on whether to classify each site as having managed or
unmanaged pervious surfaces was based on each local government's best judgments about the
characteristics of the watersheds being monitored. Table 1 summarizes the monitoring data that
were used to support model development.
38

r
Table 1. Summary of Water Quality Data Collected to Suvvort the Model
city
Managed or Oulfall
Unmanaged? Name
Land Use
Imperv-
ious
%
TN
EMC
m /L
TIP
EMC
m IL
Durham
managed
Chateau
Low Residential
15
1.30
0.32
Fayetteville
managed
clea
Low Residential
20
1.99
0.19
Chesapeake
managed
999
Med Residential
25
2.09
0.25
Durham
managed
Northgate
Med Residential
32
1.53
0.50
Chesapeake
managed
002
Med Residential
50
2.43
0.37
Raleigh
managed
7
Mixed
59
1.64
0.46
Raleigh
managed
4
Commercial
73
1.64
0.46
Durham
managed
Wortham
Commercial
73
2.18
0.39
Chesapeake
managed
007
Commercial
85
2.83
0.26
Fayetteville
managed
elms
Commercial
90
2.46
0.42
Best -fit
point for 0% imperviousness:
0
1.42
0.31
Best -fit
point for 100% imperviousness:
100
2.60
0.40
Fayetteville
unmanaged
strk
Open
0
0.75
0.10
Durham
unmanaged
Maplewood Open
4
0.80
0.13
Raleigh
unmanaged
1
Open
4
1.62
0.28
Fayetteville
unmanaged
71st
Insitutional
45
2.02
0.23
Fayetteville
unmanaged
rose
Mixed
50
1.86
0.20
Chesapeake
unmanaged
008
Industrial
57
1.43
0.20
Durham
unmanaged
Academy I
High Residential
62
1.61
0.24
Durham
unmanaged
Maxwell
Industrial
65
1.66
0.31
Durham
unmanaged
Academy 11 Mixed
59
1.94
0.49
Fayetteville
unmanaged
wins
Industrial
75
2.44
0.25
Raleigh
unmanaged
5
Light Industry
87
2.03
0.40
Best -fit
point for 0% imperviousness:
0
0.94
0.14
Best -fit
point for 100% imperviousness:
100
2.60
0.40
The researchers analyzed the monitoring data listed above to determine appropriate EMCs for
- TN and TP for impervious, managed pervious and unmanaged pervious using this process:
1. First, the monitoring data were plotted with percentage impervious on the x-axis and nutrient
concentrations on the y-axis. The managed pervious sites were considered separately from the unmanaged
pervious sites.
2. Then, the researchers determined the best -fit points for 100% impervious, 100% managed pervious and
100% unmanaged pervious. (Note: 100% managed pervious on the graph is equivalent to 0% impervious
for the managed sites. Likewise, 100% unmanaged pervious on the graph is equivalent to 0% impervious
-• for the unmanaged sites). The best -fit points were determined through trial and error by testing different
values in the graph and determining which points resulted in the highest r-squared values.
Figure 2 below shows the graphs and illustrates how the EMCs were determined.
MU

Figure 2. Graphs of the TN and TP EMCs from the Monitoring Sites
1 42 = TIC E10C for
Managed Perviouz
2 60 = IN EMC for
TN EMCs from Developments Impervio�.i '.rPaW
Devela ments with Mana ed Pervious:
y=0.0118x+1.42
♦ R2= 0.50
■
♦ Developments with Unmanaged Pervious:
=0.0166x+0.94
■ R2 = 0.69
1 0 20
o.94 = TtI E—klC fur
Unmanaged Perviorrw
0.3 i = TP EAi1iY for
Ivlanaged ervioUZZ
,D.6Q
Developments with Managed Pervious:
y = 0.0009x + 0.31
R2=0.15
■
Developments with Unmanaged Pervious:
■y = 0.0026x + 0 A 4
R2 = 0.49
E 041
i
0.301
W
0.20
0.1LY
40 60 80 100
Percent Impervious
20
0.14 = TP EMC for
Unmanaged
Pervious
TP EMCs from Developments 0.40 = TP Et41iinas
pet��ious Areas
5
40 60 80 100
Percent Impervious
40

The graphs in Figure 2 above show a much higher correlation within the TN data than within
the TP data. The researchers think this difference may be attributable to the greater influence of
landscape maintenance on TP concentrations than TN concentrations. That is, developments
with similar percentages of impervious surfaces will show greater variations in TP than TN
concentrations if one is managed with healthy, abundant vegetation and the other has sparse
vegetation and erosion problems.
In addition to the concentrations for impervious, managed pervious and wooded pervious
'~ developed as shown above, the model also splits the "impervious" category into transportation
impervious and roof impervious. For TP, this decision was based on research conducted by
Waschbusch et al. (1999). This research showed that the TP concentration of rooftop runoff is
^� only 37% of the TP concentration in runoff from roads (Waschbusch et al., 1999).
Unfortunately, these researchers did not collect data on TN concentrations. Therefore,
researchers at NCSU used their best professional judgment to estimate that TN concentration of
rooftop runoff is 75% of the TN concentration of roadway runoff. The TN "discount" was
awarded based on the fact that roads receive a greater amount of organic nitrogen (leaf litter, etc.)
and fertilizer than roofs. However, the majority of TN from impervious surfaces is likely to
originate from deposition of NOx, which is likely to be similar for both roofs and roads. Table 2
summarizes how this information is applied to the EMC values for the various land uses.
Table 2. Summary of the EMC Values and Information Sources
TN
TP
Land Use
EMC
EMC
Source of Information
m IL)
(mg/
Transportation
2.60
0.40
Best -fit points for the TN and TP graphs for managed
impervious
and unmanaged pervious surfaces for the 100%
impervious value of x.
Roof impervious
1.95
0.15
75% of the transportation impervious EMC (based on
best professional judgment)
37% of the transportation impervious EMC (based on
research by Waschbusch et al., 1999)
Managed
1.42
0.31
y-intercept of graphs of TN and TP concentrations for
pervious
managed pervious surfaces
Wooded
0.94
0.14
y-intercept of graphs of TN and TP concentrations for
pervious
managed pervious surfaces
Development of the Residential Worksheet
In order to use the Simple Method effectively, it is necessary to know how much of the
development lies in each of the land uses given in the table above. This is a simple exercise when
the footprints of all buildings, parking lots, roads, lawns, landscaped areas, etc. are shown on the
plans. This is nearly always the case for commercial, industrial and higher -density residential
development. However, for larger -lot residential developments, plans are often show only lot
and right-of-way boundaries. The Tar -Pamlico model includes a "Residential Worksheet" that
allows the user to input known information and determines the acreage in each of the four major
land uses. The worksheet calculations are based on data developed by the City of Raleigh on the
relationship between lot size and impervious area.
41

The information that is required in the Residential Worksheet should be fairly simple for the
developer to determine based on the development plans:
• Average lot size in acres,
• Percentage of right-of-way that is impervious,
• Total acres in lots,
• Total acres in protected stream buffer area,
• Total acres in rights -of -way,
• Total acres in comrnunity space (and the land use break -down of that space), and -�
• Lot acreage in buffer or wetland.
The City of Raleigh has done a study of its various zoning categories (in dwelling units per acre) and the corxesponding levels of imperviousness that would be expected per lot. For the purpose
of this model, the dwelling units per acre were converted to average lot size in acres and graphed
with lot size on the x-axis and percentage lot area in impervious surface on the y-axis (see Figure -�
3 below). The equation of the best -fit line was:
Percentage impervious = 0.148 * (average lot size)-1.48
x r;i., of Ro1P;cvWQ Tlatn nn T.nt %7P Vi-M]IR T.nt Imnerviousness
Dwelling Units
per acre
Size of lot
(acres)
Lot area in impervious
surface (percent)
Lot area in managed
pervious (percent)
1
1.00
0.14
0.86
2
0.50
0.22
0.78
4
0.25
0.30
0.70
6
0.17
0.35
0.65
8
0.13
0.38
0.62
Figure 3. Graph of Lot Size Versus Percentage Impervious
Percentage Impervious of Various Lot Sizes
0.45
H 0.40
a 0.35
m 0.30
Q
E 0.25UR--
°�0.20
m
0.15
0.10
a 0.05
0.00
0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00
Lot Size in Acres
42

Based on Schueler's Site Planning Manual (1995), researchers estimated that 60% of lot
imperviousness is for transportation (driveways, parking) and 40% is for roofs. This yields the
following two equations:
Transportation impervious = 0.089 * (average lot size)-1-41
Roof impervious = 0.059 * (average lot size)-0-411
The above equations are used in the Residential Worksheet to directly compute transportation
and rooftop impervious areas based on values provided by the user for average lot size and total
acreage in lots. The user also enters as "Wooded Pervious" the acreage of any protected buffers
or wetlands within lots. The spreadsheet calculates the acreage of managed pervious areas as the
total development acreage minus the sum of the impervious and the wooded pervious values.
In addition to computing the pre- and post -development TN and TP export coefficients, the
Tar -Pamlico model also computes export coefficients. from developments after BMP installation.
A review of the efficiencies follows in the next section.
Summary of Improvements to Export Calculation Method
The Tar --Pamlico model is an improvement over the Neuse model for the following reasons:
^. 1. The model is more accurate than the Neuse model, which actually overestimates TN
loading, especially for developments in the 40 to 60 percent impervious range. Figure 4
below shows the export coefficients found by the Tar -Pamlico model as a solid line and
.. the Neuse model as a dashed line.
2. The model has an automated version for easier use by developers and local governments.
3. The model calculates TP loads and nutrient reductions resulting from BMP installation.
^. 4. The model separates rooftop and transportation imperviousness rather than considering
them as a single entity as in the Neuse model.
5. The model has separate versions for the Piedmont and Coastal Plain that consider their
^, differing climatologic data.
Figure 4. Results of Neuse Versus Tar -Pamlico Nutrient Export Models
Neuse Versus Tar -Pamlico Model
30
! 25
G 20
r
r
C
15
y
0 10
u
COL
C
x 5
W
l)
0 20 40 60 60 100
Percent Impervious
References: Please see the references section at the end of Appendix I.
43

Appendix I. Summary of BMP Literature
Studies
Establishment ofNutrient Remowd Rates for
Storm water BMPs in
the Tar-Pamfico River Basin
A study completed by
NC State University, Biological &Agricultural Engineering
Bill Hunt, PE, and Annette Lucas
For ^'
The North Carolina Department ofEnvironment & Natural
Resources, Tar -Pamlico Stormwater Croup -'
April 11, 2003
44

Assigning Removal Efficiencies to Five Stormwater BMPs
The construction of pavement and buildings, and the clearing of land, increase the volume and
speed of stormwater runoff. When impervious or disturbed areas are created by urban
construction activities, and stormwater is not adequately managed, the environment may be
adversely affected by: (1) changes in volume, timing, and location of the stormwater
discharges, and (2) the movement of pollutants from the site to waterbodies such as tributaries
reaching the Tar -Pamlico River System and the Pamlico Sound and estuarine system. This
contributes to flooding and damage to property and habitat (stormwater quantity impacts). It
also contributes to lowering of water quality, by increasing the flow of human pollutants such
as oil, fertilizers and pesticides, and the flow of natural elements such as nitrogen, phosphorus
and sediment into the water (stormwater quality impacts). Degradation of lakes, streams and
wetlands due to urban stormwater reduces property values, raises bills from public water
utilities and reduces tourism and related business income.
The following sections will examine several stormwater Best Management Practices (BMPs)
.. and present a model for estimating BMP removal efficiencies. This model is intended to serve
the Tar -Pamlico basin, and as such only a limited amount of data is used to estimate pollutant
removal efficiencies. Only BMPs from sites with relatively similar weather to that of Central
and Eastern North Carolina are included in the study. Because of this, there are some
differences in pollutant removal rates reported herein and those from national studies that do
not make adjustments for weather regimes. Furthermore, even when only examining studies
— from the Southeastern and Mid -Atlantic states, there is evidenced a very wide range of
removal efficiencies within a practice type. This is due to site specific factors such as soil
type, monitoring period (a wet year or a dry year), or type of sample (grab or composite).
�- Only data from sites that are within certain standards are used to compute removal
efficiencies, with data from known North Carolina studies given the most weight. Finally, as
more and more data is found regarding the effectiveness of stormwater best management
-- practices, such as bio-retention, the removal rates will be expected to change. This report
illustrates this point with respect to bio-retention cells. The removal rate has been adjusted
from that of the Neuse Stormwater plan due to the influx of data from new studies. The study
of stormwater BMPs is dynamic and perhaps the State of North Carolina should consider
annual or bi-annual updates of removal efficiencies.
Structural Stormwater BMPs
An urban stormwater BMP is believed to be a 'best' way of treating or limiting pollutants in
stormwater runoff. Certain BMPs are better under certain conditions than others. The size of the
watershed, the imperviousness of the watershed, and the amount of available land for the
structure all influence the selection of a BMP. The stormwater treatment practices investigated in
this study are solely structural devices and include wet ponds, stormwater wetlands, bio-retention
areas, grassy swales and sand filters.
45

Wet Ponds, also called wet detention ponds or facilitics, have been
used in North Carolina longer than any other stormwater BM-P.
Wet Ponds are runoff -holding facilities that have standing water in
them constantly. Storm flows are held in the pond temporarily and
then released to minimize large scale flooding. Wet ponds are
characterized by larger excavation volumes and have forebays
located where the inflow enters the BLIP. The primary removal
mechanism is settling while stormwater runoff resides in the pool.
Nutrient uptake also occurs through biological activity in the pond.
Wet ponds can be designed to have vegetated fringes or zones (as
in Figure 5), and the plant roots hold sediment and use the
nutrients that are often contained in urban runoff. Developers can
design the wet ponds to look like natural lakes and enhance the Figure 5. Wet Pond with
value of surrounding property. Mosquito larvae -eating fish live in
the pond to keep mosquito problems to a minimum. Wet ponds Aquatic Fringe
can be used for any size of drainage area. In North Carolina, wet ponds treat watersheds as small
as 0.75 acres and as large as several hundred acres. Wet ponds may cause community concerns
regarding safety; there is an increased liability due to drowning risk because of their relative
depth. Additionally, wet pond effluent is often warmer than base stream water, causing thermal
pollution and potentially damaging downstream aquatic habitats.
Stormwater Wetlands,' also called constructed
wetlands, are comparable to wet ponds but are
much shallower and more heavily vegetated
with wetland plants. In many stormwater
wetlands the average depth of water is
approximately 1-1.5 feet. They serve as a natural
filter for urban runoff and also help to slow the
flow of water to the receiving waters and
replenish ground water. As stormwater runoff
flows through the wetland, pollutant removal is
achieved by settling, adsorption and biological
uptake within the practice. Wetlands are
effective stormwater practices in terms of
pollutant removal and also offer aesthetic value.
When properly designed (Figure 6), stormwater
wetlands have excellent wildlife habitat potential
Figure 6. Stormwater Wetlands can be
designed to incorporate diverse vegetative
species.
(MWCOG, 1992). In North Carolina,
constructed stormwater wetlands have been located on watersheds as small as four to five acres,
but they are most commonly used for larger drainage areas and typically serve watersheds ranging
from 15 acres to over 100 acres. Thanks to its vegetative cover, wetland effluent is typically
cooler than that of wet ponds, minimizing the impacts of thermal pollution.
1 For regulatory purposes under the Clean Water Act, the term wetlands means "those areas that are
inundated or saturated by surface or ground water at a frequency and duration sufficient to support,
and that under normal circumstances do support, a prevalence of vegetation typically adapted for life
in saturated soil conditions.
46

There are also some limitations to stormwater wetlands. Wetlands consume a relatively large
amount of space making them an impractical option on sites where surface land area is
constrained or land prices are high. They have, therefore, limited applicability in highly urbanized
settings. There can also be a public perception that wetlands are a mosquito source, although
design features can minimize the potential of wetlands becoming a breeding area for mosquitoes
(McLean, 2000).
Wetlands and Wet Ponds: When choose which?
Wetlands and Wet Ponds are similar practices in that each tends to treat larger watersheds, have
standing water year round, and are sited in roughly the same types of locations. There are
advantages to each that lead a designer to select one over the other. These selection guidelines are
summarized below:
1. Wet Ponds are substantially deeper than stormwater wetlands. A four feet difference in
average depth can lead to a 50% increase in construction cost. If land costs are relatively
low, a stormwater wetland will be a less expensive stormwater BMP to construct, even
though wetlands do have the added cost of vegetation purchase and planting.
2. Stormwater wetlands typically occupy more land than wet ponds. This is due to the fact
that the height of water rise over normal pool (the elevation at which the water is
typically) is much higher in a wet pond than a wetland. This relates to a wet pond's
�. surface area only approaching 60-70% of that of a stormwater wetland. In areas where
land costs are relatively higher, the opportunity cost of using extra land may easily offset
the increased cost of constructing a wet pond, making the wet pond a more economically
viable option.
3. Contrary to initial estimation, wet ponds do not cost less than wetlands to maintain. This
is due to the nature of each BMP. A standard wet pond used as an amenity is often well -
manicured, with the surrounding lawn mowed to the banks and all vegetation along the
side (wetland plants) being killed by direct herbicide application. The wetland's plants are
designed to maintain a natural state; that is, there is very little cosmetic maintenance to a
wetland when compared to many wet ponds. Other maintenance needs such as outlet
inspection and forebay cleaning are the same for each practice. Long term maintenance
needs for a stormwater wetland do potentially include plant harvesting, but a recent study
by Wossink and Hunt (2003) suggests that wet pond maintenance in the long run is
substantially higher than that of stormwater wetlands.
4. Liability issues are present for each practice. Ponds tend to be much deeper so the risk of
drowning is higher for wet ponds than it is for wetlands. However, wetlands are excellent
environments for animals such as frogs and snakes, with the latter potentially being an
issue of concern, if there is easy and uncontrolled access to the stormwater wetland by
young children.
5. Aesthetics can be a determining factor in BMP selection. If an open water surface is
desired for aesthetic reasons, then a wet pond will be more appropriate than a stormwater
wetland. To many, a stormwater wetland is still viewed as a "swamp" and has unfavorable
connotations to some.
6. The state of North Carolina counts a stormwater wetland to be a riparian buffer, but the
state does not view a wet pond to be the same. This is important when a new
development is required to install buffers around all blue -line (from a USGS topographic
map) bodies of water. If a pond is constructed in a watershed with buffer requirements
47

(such as the Tar -Pamlico basin), it would then need to have a 50' buffer established
around its perimeter. This land would need to be dedicated apart from a developed
activity in addition to the surface area of the wet pond. A wetland, since it is vegetated --
already, does not need a buffer to be established in addition to itself.
Pollutant removal rates perhaps provide the biggest incentive to choose one practice over
the other. If a stormwater wetland is credited with a better pollutant removal rate, say, for -�
phosphorus, than a wet pond, a developer can just barely meet the nutrient reduction
requirement by installing a stormwater wetland in lieu of a wet pond, then the former
BTMP will be selected. —
Three other practices are used to treat smaller watersheds. Each of the three is reviewed below.
Sand filters are usually two -chambered
stormwater treatment practices; the first
chamber is for settling, and the second is a filter
bed filled with sand or another filtering media.
As stormwater flows into the first chamber,
large particles settle out, and the finer particles
and other pollutants are removed as stormwater
flows through filtering media. At the bottom of
the sand layer, an underdrain pipe typically
connects the treated water with the existing
drainage network. Sand filters, in general, are
good options for relatively small drainage areas
in ultra -urban environments where space is
limited and original soils have been disturbed
(as in Figure 7).
Figure 7. Sand filters can be designed
to sustain vehicular traffic or not as is
the case at this site in Durham.
Moreover, sand filters are particularly well suited to treat runoff from stormwater hotspots2
common in ultra urban areas because stormwater treated by sand filters has no interaction with,
and thus no potential to contaminate groundwater.
Sand filters are best applied on small sites and can be used on sites with up to about 6% slopes. It
is difficult to use sand filters in extremely flat terrain, as they require a significant drop in —
elevation (ranging from two to five feet) to allow runoff flow through the filter. There are several
modifications of the basic sand filter design, including the surface sand filter, underground sand
filter and the perimeter sand filter. All of these filtering practices operate on the same basic —
principle. Underground and perimeter sand filters are particularly well suited for ultra -urban
watersheds as they consume no surface space. The perimeter sand filter can be applied with as
little as 2 feet of drop in elevation. In this report we address the economics of the latter type of —
sand filter specifically. The first sand filter in North Carolina was installed in the early mid-1990's.
Their use is currently not widespread due to the costs of construction. Sand filters are designed
2 Stormwater hotspots are land uses or activities that generate highly contaminated runoff and include:
commercial parking lots, fueling stations, industrial rooftops, outdoor container storage of liquids and
loading/unloading facilities and vehicle/equipment service, maintenance/washing/steam cleaning
areas.
48

for impervious watershed in particular, and typically one sandfilter treats a drainage catchment of
less than a few acres.
Bioretention/rain gardens in many
respects are landscaped and vegetated
�- filters for storm water runoff. Surface
runoff is directed into shallow, landscaped
depressions (Figure $). These depressions
are designed to incorporate many of the
pollutant removal mechanisms that
operate in forested ecosystems and are:
strikingly similar in vegetation types to the
poccosins of eastern North Carolina .
Trees and shrubs axe planted in bedding
material consisting of a high percentage of
sand, and lesser amounts of silt, clay and
organic matter. During rain events, Figure S. This Rain Garden in Kinston was the
stormwater ponds above the mulch and first one constructed in Eastern North
soil in the system. Runoff from larger Carolina. The site located at the Neuseway
storms is generally diverted past the Education Center serves aesthetic, water quality
facility to the storm drain system. The and educational purposes.
remaining runoff filters through the
mulch and prepared soil mix. Typically, in
clay soil sites, the filtered runoff is collected in a perforated underdrain and returned to the storm
drain system. Bioretention systems are generally applied to small sites and in a highly urbanized
setting. Bioretention facilities are ideally suited to many ultra -urban areas as they can be fit into
existing parking lot islands or other landscaped areas.
Because bioretention can potentially fulfill two purposes, (1) water quality control and (2)
landscaping requirements, their use is expected to increase. For example, in 1997 there were no
bioretention areas in North Carolina; whereas today, it is the secondly most common planned
practice in Greensboro, the state's third largest city (Bryant, 2001). Bio-retention areas typically
serve small watersheds such as (portions of parking lots, or residential run off areas. In North
Carolina, the majority of bioretention areas served watersheds ranging from one to two acres.
Their use is poised to grow further, pending several studies conducted by N.C. State University
and other universities, particularly if the research shows that this BMP works to remove
pollutants at a rate as high as is currently anticipated.

Grassy Swales are the simplest and most prevalent
stormwater BMPs in North Carolina. Their use is typically
limited by overwhelming amounts of runoff which cause
erosion of swales. There are some ways to mitigate this
erosion by including changing the slope of the swale or
incorporating turf reinforcement matting to strengthen
the grass lining (see Figure 9). Swales are often triangular
in shape and are constructed by using relatively simple
equipment. The use of grassy swales is very limited in
ultra -urban areas, but swales are often easily installed in
residential environments. Maintenance of wet swales can
be particularly important in neighborhoods. It is essential
that grassy swales don't become collectors of nutrient rich
grass clippings, as this nutrient source is easily transported
to adjoining water bodies by water flowing through the swale.l
Figure 9. Turf reinforcement mats
increase allowable velocities for
grassy swales, making swale use
more possible.
Table 4. Summary of the five structural stormwater BMPs by relative size of the
associated drainaLye area.
BMP Relative size of commercial/residential drainage area
Large Small
Wet Pond X X
Stormwater Wetland X
Sandfilter* X
Bioretention/Raingarden** X
Grassy Swales X
*Only effective with a significant drop in elevation (for perimeter sandfilter at least two feet)-
** In clay soils a significant drop in elevation 4 feet is typically required.
Above, several structural options were described for achieving water quality improvements in
stormwater runoff, all of which have various technical characteristics (design requirements and
site constraints), ecological characteristics (i.e. capabilities regarding pollution control) and
economic characteristics (maintenance requirements and construction costs).
While each may be constructed based upon design constraints, the different BMPs are shown to
remove nutrients at varying efficiencies. The next section will summarize pollutant removal
abilities for TN and TP for each of the five stormwater practices discussed.
3 BMPs should only be used in areas where the physical site characteristics are suitable. Some of the
important physical site characteristics are soil type, watershed area, water table, depth to bedrock, site size
and topography. If these conditions are not suitable, a BMP can loose effectiveness, require excessive
maintenance or stop working.
50

,..
Pollutant Removal Effectiveness
Chmatologic Screening
A large body of national research data was available on the removal effectiveness of the four
types of BMPs. Particularly there was a considerable amount of data for the following cities:
Austin TX; Baltimore, MD; Chicago, IL; Minneapolis, MN; Seattle, WA and Tampa, FL.
However, North Carolina's climate is substantially different from many other parts of the U.S.
,^ with respect to temperature and precipitation. Because of this, a screening procedure was used to
decide which data to use.
The out-of-state cities' weather was compared to the weather of three cities in North Carolina:
Charlotte, Raleigh -Durham and Wilmington (Figure 10). These three cities represent the weather
conditions found in eastern and central North Carolina, and may best approximate weather in the
Tar -Pamlico River Basin.
Temperature and rainfall data over the period of 1990 -2000 was collected for the six out -of state
and the three in -state cities using both the Midwestern Climate Information System (MICIS,
2000) and the Southeastern Regional Climate Center's CIRRUS system (CIRRUSweb, 2000).
Average monthly mean temperature and average monthly precipitation level were assessed for
each city and statistically analyzed for significant differences.
-- Figure 10. Location of cities in North Carolina whose weather was compared to
that of cities nationwide.
Raleigh -Durham
■. III I III I M Lan i
I—
.. Seattle, WA; Minneapolis, MN, and Chicago, IL, were shown to have either drastically different
rainfall distribution and amounts or temperatures or both. This is detailed graphically in
Appendix I-1. The temperatures and precipitation levels of the remaining three cities: Austin TX,
Baltimore, MD, and Tampa, FL, where similar to the climate of at least one of the three cities in
North Carolina. Comparisons show that Austin, and Charlotte had similar temperatures, though
Charlotte was somewhat cooler in the winter. Except for the month of June, the difference in the
average monthly rainfall in Charlotte and Austin, TX, was less than 1". Raleigh -Durham and
Baltimore, MD were quite similar both with respect to temperature and rainfall, with Raleigh -
Durham being slightly wetter and warmer. Again differences in rainfall were within 1" on a per -
month basis. Finally, Wilmington, NC and Tampa, FL, were surprisingly similar. Precipitation
„� 51

levels for each city were high in late summer and early fall, reflecting tropical activity at both
locations. The rainfall amounts for July -September were 7-8" for both cities. Tampa was warmer
in the winter but the difference with Wilmington was within 10°F. Therefore pollution removal -�
data collected from the Austin, TY, region, the Baltimore -Washington metropolitan area, and the
northern two-thirds of Florida were all included in the analysis and were added to what had been
collected in North Carolina and Virginia. Appendix I-1 provides a graphical presentation of each --.
comparison made.
Assigning Pollution Removal Efficiencies
The two principal sources of best management practice effectiveness were (1) the ASCE/EPA
joint venture National BMP pollutant removal database (found at —'
http://www.bmpdatabase.com), and (2) The Center for Watershed Protection's National
Pollutant Removal Performance Database (2000 version). Each is a collection of studies
reported by either research agencies (such as universities or water management districts), or
governments (state, county, or municipal). Research deemed unacceptable by the governing
bodies of each database is not included in either database, making these two resources the
most credible sources of this type of information in America. Other sources, particularly
research projects from NC State and other regional land-grant schools, were used as noted.
Appendix I-2 provides an overview of all the data sources used to assess the pollutant removal
efficiencies.
Based on the data sources described above, the effectiveness of each of the five BMPs in the
Southeast and Mid -Atlantic was determined. For each BMP the data on removal of total
phosphorus (TP) and total nitrogen (TN) were analyzed for scale effects by relating the
removal effectiveness to the size of the watershed. Linear regression was used for this
purpose. Based on the results of this statistical analysis, each practice was assigned a single
removal rate (the median removal efficiency) in the cost-effectiveness analysis. That is,
assuming the practice is designed properly, it will work comparably well whether it serves a
10-acre watershed or a 50-acre watershed. The median pollutant removal efficiencies for
each of the practices are reported in Table 5 on the following page.
There was a wide range of scatter in the data with respect to pollutant removal efficiencies. No
significant relationship could he assessed between removal efficiency and watershed size (note
Figures 11 and 12) and therefore median pollutant removal efficiencies were used for this report.
This is certainly an area for future research and adaptation. Median efficiencies were chosen in
lieu of mean efficiencies because the former discounts the impact of skewing data. Outliers, such
as negative pollutant removal efficiencies have a more pronounced effect on the results. its such,
median removal rates better represent the pollutant removal to expect.
Ideally, a relationship could be developed relating removal efficiency with the ratio of BMP
practice size to contributing watershed size. It is generally assumed that the smaller the ratio is,
i.e., a small relatively BMP with a large drainage area, the poorer the practice's performance at
removing pollution. The opposite is suspected to hold true if the ratio is larger. However, there is
very little data to support this assumption and the data is very widely scattered (as shown in an
example of Figure 13). Because of a lack of supporting data, the BMP efficiency model can not at
this time factor in practice size to watershed size with respect to pollutant removal. Perhaps a
later version of the model can incorporate this relationship as new findings are added to the BMP
database.
52

Table 5. Removal Efficiencies assigned to each of the stormwater BMPs to be utilized in
the Tar -Pamlico Basin. These numbers account for prior standards, new research, and
anticipated maintenance.
TP
TN
Removal
Number
Removal
Number
BMP Type
Efficiency fzciency
of Sites
Efficiency
of Sites
Wet Ponds
40
28
25
27
ormwaler
35
14
25
14
etlands
Sand Filters
45
11
35
12
Bio-
35
8
40
4
-retention
Grassy
20
16
20
11
Swales
The TN results displayed in Table 5 vary slightly from those presented by the Neuse Stormwater
Team. This is due to the increased amount of data that has been collected since the Neuse Team
completed its work in early 2001. Most striking is the change associated with bio-retention. Since
2001, the number of field studies has quadrupled (from 1 to 4), giving a much firmer, though still
not firm enough, idea of how well bio-retention devices work to remove both TP and TN.
Explanation of Efficiencies by BMP
Wet Ponds. A total of 28 studies contained data regarding pollutant removal from wet ponds,
which is by far the most of any practice studied, reflecting the relative abundance of wet ponds
throughout the Mid-Adantic and Southeastern states. TP removal rates varied from -50 (meaning
., the wet pond added TP to the receiving stream) to 88%. TN removal rates ranged from -1 to
55%.
Stormwater Wetlands. Fourteen studies chronicled the effectiveness of stormwater wetlands.
TP rates ranged from -61 to 75%. TN removal rates were lower than is nationally accepted,
ranging from -12 to 55%. The median removal rate of about 25% is 15% less than what the
., Neuse Stormwater rules stated. These median removal rates are generally higher for appropriately
sized stormwater wetlands.
Sand Filters. Twelve studies documented the efficiencies of sand filters. Removal rates for this
practice are almost always initially higher due, with the rates dropping when the required
maintenance is not performed. TP removal rates ranged from 10 to 80%. TN rates varied from 8
to 71 %. The form of nitrogen that sand filters release into the environment is NO,-N, which is
very difficult to remove, once in the water column. It will be imperative that the practice is
maintained on a regular basis to maintain such high removal efficiencies.
Bio-retention. Only eight studies (4 of them in the laboratory) document the effectiveness of
bio-retention areas to remove TP. Fewer still (four) research this BMP's ability to remove TN. All
of the latter are field studies. There is a significant chance these removal efficiencies will continue
53

to change. Several NC DENR funded demonstration research projects are studying the
effectiveness of bio-retention areas and will be completed in 2003 and 2004. TP removal rates
vary from -3% to 87%, while TN removal efficiencies vary from 33% to 65%. A conservative
removal rate of 40% is being suggested for the latter due to the lack of studies documenting bio-
retention removal efficiency. The rate is, however, 15% higher than what is given in the Neuse
Stormwater report.
Grass Swales. Without a doubt grass swales have the highest variability of removal efficiencies.
Swales that are maintained and from which grass clippings are removed can have relatively high
removal rates for TP and TN. Those swales, however, which are unmanaged or managed poorly,
will add substantial amounts of TP and TN to the environment. A total of 16 studies document
swale efficiencies. TP and TN removal efficiencies both range from -100 to 99%.
100
90
80
0 70
A
60
U 50
W
> 40
0
E
30
20
10
0
Figure 11. TSS Removal Efficiency - Stormwater Wetlands
1 10 100 1000
Watershed Area (acres)
10000
54

:
x
"
.............

Acknowledgements
The authors would like to acknowledge several agencies and people who significantly contributed -�
to the research project. The Department of Environment and Natural Resources funded the
project. Ms. Desiree Tullos, Ph.D. Candidate in Biological and Agricultural Engineering at N.C.
State was instrumental in obtaining pollutant loading information. Representatives from several —
communities were particularly helpful, including John Cox (Durham), Greg Caisson
(Fayetteville), Mark Senior (Raleigh), and officials from the Hampton Roads (VA) Council of
Governments. Each was able to provide data used to establish pollutant loading information for
the Tar -Pamlico River Basin. Portions of this report were prepared by Dr. Ada Wossink in the
department of Agriculture and Resource Economics. Finally, a special thank you goes to all the
Tar -Pamlico municipalities, counties and citizen groups who helped identify content to be
included and researched for this report. Without them and the leadership of NC DENR's Rich
Gannon the report would not have been possible.
REFERENCES
CIRRUSweb. 2000. Southeastern Regional Climate Center. SC Dept. Natural Resources,
Columbia, SC. ht watendnnstate.sc.us climate sercc cirrushome.html
City of Chesapeake, VA. April 2001. Wet Weather Sampling Results.
City of Durham, NC. October 2000. City of Durham Stormwater Management Plan for the
Neuse Nutrient Sensitive Water Strategy.
City of Fayetteville and Cumberland County, NC. November 2002. Summary of Wet Weather
Monitoring. Oaden Environmental and Engineering Services.
City of Raleigh, NC. November 2002. Summary of Wet Weather Monitoring.
Davis, A.P., M. Shokouhian, H. Sharma, and C. Minami. (2001), Laboratory study of biological
retention for urban stormwater management. WlaterEnvironmentResearch 73(1): 5-14. —
Davis, A. P. (2002) Personal Communication. Director, Maryland Water Resources Research
Center and Professor, Department Civil and Environmental Engineering, University of
Maryland,College Park, MD.
Hunt, W.F., A.R. Jarrett, J.T. Smith. 2002. Optimizing Bio-retention Design for Nitrogen
Removal. IN: Proceedings of the ASAE International Conference, 2002. Chicago, IL.
Midwest Climate Information System (NIICIS). 2000. Midwestern Regional Climate Data Center.
University of Illinois, Urbana -Champaign. htip://mcc.sws.uiuc.edu/Introduction
/micis.httxil
NC Division of Water Quality. August 10, 1999. Neuse River Basin: Model Stormwater
Program for Nitrogen Control, Raleigh, NC. 35 pp.
56

r..
Schueler, T. S. Dec. 1995. Site Planning for Urban Stream Protection. Metropolitan
Washington Council of Governments. Silver Spring, MD 231 pp.
Waschbusch, R. J., W. R. Selbig and R. T. Bannerman. 1999. Sources of Phosphorus and Street
Dirt from Two Urban Residential Basins in Madison, Wisconsin, 1994-95. U.S.
Geological Survey. Water Resources Investigations Report 99-4021, Middleton, WI. 22
pp,
Wossink, A. and W.F. Hunt. 2003. The Economics of Structural Stormwater BM -Ps in North
Carolina. NC WRRI Project # 50260. Raleigh, NC. (under review)
57

yu.uu
80.00
70.00
so 00
so 00
E
40.00
30.00
20.00
10.00
0 00
Appendix I-1. Precipitation and Temperature Comparison of Six
U.S. cities with three cities in North Carolina.
Wilmington and Tampa are shown to have very similar temperature plots (typically within 10°F
of each other). Neither city has an average temperature approaching biological zero. However,
Chicago's temperatures are much colder and remain either below or within biological zero
(accepted around 5°C) for five of twelve months of the year. It is not reasonable to accept data
from the upper Midwest as similar to that of Central and Eastern North Carolina due to this
temperature discrepancy.
Monthly Average Temperature for Wilmington, Chicago, and Tampa
Yz
o
-ram
d
t
yi
C
M
k
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month ..�
ID Wilmington ■ Chicago ❑ Tampa
58

L1
A comparison of precipitation amounts from Wilmington and Tampa show that each city
received high amounts of rainfall at approximately the same times of the year, with Wilmington
being slightly wetter. The relationship is particularly Close during the summer and fall months
reflecting tropical activity. This is particularly important because large storm events are often
blamed for BMP "release" of pollutants, due to large quantities of water flushing nutrients from
the system. Because Wilmington and Tampa are so similar in this regard, they are deemed to be
good "paired" cities. However, as expected, Chicago's rainfall does not reflect any high monthly
rainfall totals and are substantially lower than that of both Wilmington and Tampa in most
'~ months.
Precipitation Data for Wilmington, Chicago, and Tampa
Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
Wilmington ■Chicago El Tampa
w

Charlotte and Austin are shown to be very similar in temperature on a monthly basis, with Austin
being slightly warmer (but always within 10T). Both cities remain at or above biological zero
(5,q. Seattle, too, remains at or above biological zero, and does reflect similar temperatures to
Charlotte during the late fall through early spring. However, Seattle has a much more moderate
summer temperature, with differences near i 5T. Temperature alone may not cause Seattle's data
to be rejected, but it does not support the use of Pacific Northwest BMP removal efficiencies,
either. An examination of rainfall is necessary.
Temperature Comparison of Charlotte, Austin, and Seattle
..

Seattle has a much different monthly rainfall distribution to that of Charlotte. While Charlotte's
rainfall distribution is relatively evenly distributed throughout the year, Seattle receives the vast
majority of precipitation from late fall through early spring. Rainfall differences are over two
inches for much of the summer and fall. Contrastingly, Austin and Charlotte are within one inch
more most of the year and only exhibit a two inch difference in March when Austin receives
^' more rainfall. Charlotte does receive slightly more rainfall on an annual basis than Austin.
Precipitation Comparison of Charlotte, Austin, and Seattle
61

90
80
70
60
u
m 50
m
`a
E 40
v
r
as
20
40
a
Baltimore and Raleigh have very similar temperatures, never exceeding 6°F. The temperature
difference, however, between Minneapolis and Raleigh are substantially different (over 20°F) in
much of the winter, as the average temperature in the latter city is below biological zero from
November through March.
Temperature Comparison of Raleigh, Baltimore, and Minneapolis
C
an 1:ef7 Mar Apr May Jun Jul Aug Sep Oct Nov D
Month
0 Raleigh ■ Baltimore Q Minneapolis
62

Raleigh and Baltimore have similar rainfall totals, often within 0.20" on a monthly basis with
-� occasional exceptions reaching over 1 inch. Minneapolis is substantially direr in the winter, with
over two inch differences in December through March. These differences coupled with
substantial temperature differences prohibit the use of stormwater BMW effectiveness data from
studies from states of the upper Great Plains when proposing efficiencies for North Carolina.
Precipitation Comparison of Raleigh, Baltimore, and Minneapolis
6.00
5.00
4.00
c
m 3.00
�+ c
2.00
1.00
PM
0.00
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month
ICE Raleigh S Baltimore © Minneapolis
63

Appendix I-2. Sources of information for BMP Pollutant Removal
Effectiveness.
Practice Type
State
Researchers or Agency
Reference
Stormwater Wetlands
FL
Rushton and Dye
CWP
Stormwater Wetlands
NC
Tweedy and Broome
Personal Communication
Stormwater Wetlands
VA
Northern VA Soil & Water
District
NBMPD
Stormwater Wetlands
FL
FL DOT/ USGS
NBMPD
Stormwater Wetlands
MD
Baltimore City Water
Quality Management Offic
NBMPD
Stormwater Wetlands
FL
EPA/ Florida DER
NBMPD
Stormwater Wetlands
VA
Yu
Personal Communication
Stormwater Wetlands
MD
Althanus and Stevenson
CWP
Stormwater Wetlands
MD
MD Center for
Environment & Estuarine
Studies
NBMPD
Stormwater Wetlands
VA
Yu
Personal Communication
Stormwater Wetlands
VA
Yu
Personal Communication
Stormwater Wetlands
FL
Carr and Rushton
CWP
Stormwater Wetlands
FL
Harper, Wanileista, Fries,
and Baker
CWP
Stormwater Wetlands
NC
Bass
Personal Communication
Stormwater Wetlands
FL
Blackburn, Pimentel, and
French
CWP
Stormwater Wetlands
VA
Yu
Personal Communication
Sand Filter
TX
City of Austin
CWP
Sand Filter
TX
Barton Springs/ Edwards
Aquifer Conservation
District
CWP
Sand Filter
TX
Tenney, Barrett, Malina,
Charbeneau, Ward
CWP
Sand Filter
TX
Citv of Austin
CWP
Sand Filter
VA
Bell, Stokes, Gavin, and
N u en
CWP
Sand Filter
NC
Hunt
Unpublished Data
Sand Filter
TX
City of Austin
CWP
Sand Filter
TX
Citv of Austin
CWP
Sand Filter
i 1K'
City of Austin
CWP
Sand Filter
TX
Welborn and Veenhuis
CWP
Sand Filter
TX
Barrett, I{eblin, Malina,
Charbeneau
CWP
Sand Filter
FL
EPA/ Florida DER
NBMPD
Bio-Retention
MD
Davis
Personal Communication
Bio-Retention
MD
Davis
Personal Communication
Practice Type
State
Researchers or Agency
I Reference
64

Bio-Retention
MD
Davis, Shokouhian, Sharma,
Miniami
Water Environment
Research
Bio-Retention
MD
Davis, Shokouhian, Sharma,
Miniami
Water Environment
Research
Bio-Retention
VA
Yu
Personal Communication
Bio-Retention
NC
Hunt
Unpublished data -
Greensboro
Bio-Retention
NC
Hunt
Unpublished data- Chapel
Hill
Bio-Retention
PA
Hunt, Jarrett, Smith
ASAE Conference
Proceedin s, 2002
Wet Detention Pond
FL
FL DOT/ USGS
NBMPD
Wet Detention Pond
FL
Dormman, Hartigan, Steg,
Quasebarth
CWP`
Wet Detention Pond
VA
Occoquan Watershed
Monitoring Laboratory
CWP
Wet Detention Pond
FL
Gain
CWP
Wet Detention Pond
FL
Martin
CWP
Wet Detention Pond
FL
Florida DOT / USGS
NBMPD
Wet Detention Pond
NC
Wu
CWP
Wet Detention Pond
NC
WRRI / UNCC
NBMPD
Wet Detention Pond
TX
City of Austin
CWP
Wet Detention Pond
NC
Wu
CWP
Wet Detention Pond
NC
Borden, Dorn, Stillman,
Liehr
CWP
Wet Detention Pond
FL
USGS
NBMPD
Wet Detention Pond
TX
Lower Colorado River
Authotity
CWP
Wet Detention Pond
TX
city of Austin
CWP
Wet Detention Pond
FL
Environmental Research
and Design, Inc / St. John's
River Water Mngmt.
District
NBMPD
Wet Detention Pond
VA
Yu
Personal Communication
Wet Detention Pond
FL
Holler
CWP
Wet Detention Pond
VA
Yu
Personal Communication
Wet Detention Pond
FL
Rushton, Miller, Hull
CWP
Wet Detention Pond
FL
Rushton, Miller, Hull
CWP
Wet Detention Pond
VA
Occoquan Watershed
M nitoring Laborato
CWP
Wet Detention Pond
FL
Cullum
CWP
Wet Detention Pond
NC
Borden, Dorn, Stillman,
Liehr
CWP
32

Practice Type
State
Researchers or Agency
Reference
Wet Detention Pond
FL
Kantrowitz and Woodham
CWP
Wet Detention Pond
FL
Northwest Fl, Water
Management District
NBMPD
Grassy Swale
FL
Dorman, Hartigan, Steg,
Quasebarth
CWP
Grassy Swale
FL
Harper
CWP
Grassy Swale
FL
Kercher, Landon, Massarelli
CWP
Grassy Swale
FL
Harper
CWP
Grassy Swale
VA
Dorman, Hartigan, Steg,
Quasebarth
CWP
Grassy Swale
MD
Occoquan. Watershed
Monitoring Laboratory-
CWP
Grassy Swale
MD
Occoquan Watershed
Monitoring Laboratory
CWP
Grassy Swale
VA
Occoquan Watershed
Monitoring Laboratory
CWP
Grassy Swale
TX
Walsh, Barrett, Malina,
Charbeneau, Ward
CWP
Grassy Swale
TX
Walsh, Barrett, Malina,
Charbeneau, Ward
CWP
Grassy Swale
TX
Welborn, Veenhuis
CWP
References noted:
CWP — Center for Watershed Protection's National Pollutant Removal Performance Database. 2000
NBMPD —National Best Management Practice Database (htti2://w,,v�v.bmpdatabase.com)
Much of Dr. Shaw Yu's data (from the University of Virginia) is going to be described in the National
BMP pollutant database.
zi

Appendix J. Computing the Intensity -
Duration Variable for the One -Year Storm
in Wake, Wilson and Craven Counties
Computation of the Variable "g" for Wake County
350
300
250
jp 200
`o
a
j 150
100
50
0
30
25
20
c
15
a
10
5
a
2fi 1
232
169
132
y-intercept = 104
1
18
y-intercept =18
10
Return Period in Years pog scale)
Computation of the Variable "h" for Wake County
23
24
290
100
1 10 l00
Retum Period In Years ilog scale)
25
67

Computation of the Variable "g" for Wilson County
350
300
250
16
200
S 7
y 150 144
100 y_intarcept = 112
so -
0
L
10
Return Period in Years {log scale)
30
26
20
t
15
}
10
f
Computation of the Variable "h" for Wilson County
y-intercept = 20
100
1 10 100
Return Period in Years I" scale)
28
68

0
Computation of the Variable "g" for Craven County
350
300
250
200
3
150
,Do
-intercept =127
50
0
35
30
25
r 20
a
j 15
10
5
0
1 10
Return Period In Years (log scale)
Computation of the Variable "h" for Craven County
29
23
363
100
1 10 100
Return Period in Years (Jog sukl
33
ee

Appendix K.
Techniques
Land Use Planning and Design
Reducing Road Widths
In many instances, road widths are required to be wider than needed to safely convey traffic
through residential and commercial areas. Although these wide widths are often adopted to
increase safety for automobiles, they often increase speeds through residential areas and, in so
doing, may decrease safety for pedestrians and cyclists. Also, some jurisdictions require curb
and gutter for aesthetic reasons where it is not actually necessary to control stormwater runoff.
This can result in increased flooding and also eliminates the potential for stormwater runoff
control and treatment that can occurs in properly designed and maintained roadside swales.
Most local governments model their residential street design standards after state and/or
federal highway criteria, although the traffic capacity and function of their street system is
considerably different from highways. Very few communities recognize any local road
categories that are different from established state and federal street categories. Many local
traffic engineers have simply accepted the notion that wider streets adequately address these
concerns and that wide streets are safe streets (Schueler 1995).
Narrower road widths can reduce the road surface area by up to 35 percent.
A number of communities have implemented standards that promote narrower residential
streets and have concluded this to be an attractive, safe and environmentally beneficial
alternative.
Communities should also review their standards for turnarounds to reduce the need or
unnecessary road surface. One of the most common types of turnaround is a cul-de-sac that
may have a diameter of 80 to 100 feet or more (Schueler 1995). Some communities are
recognizing that this is excessive and are choosing alternatives that create less impervious
cover, such as T-shapes. A 60-foot by 30-foot T-shaped turnaround creates only about 36%
as much impervious area as an 80-foot diameter cul-de-sac and is more than adequate for
most vehicles.
Local governments should: (1) examine community regulations governing road width and
turnaround size; (2) evaluate if the specified widths are necessary; and (3) where feasible,
make changes to reduce unnecessary road surfaces.
Reducing Minimum Parking Requirements
Parking lots are often designed to accommodate parking needs on the busiest days of the year.
For example, shopping center parking areas are often big enough to handle the busy holiday
times, but then sit vacant for much of the rest of the year. This can result in increased
nitrogen load (as opposed to maintaining open space).
70

Some management strategies that would contribute to a reduction in urban nitrogen from
parking lots:
• Use angles and smaller parking spaces.
• Use more pervious construction materials in seldom -used parking areas (Land of Sky
1995).
+ Provide public transportation to shopping centers during the peak holiday times and
-- encourage people to use it.
• Design parking areas to drain in sheet flow into stable vegetated areas.
Minimizing Use of Curb and Gutter
Runoff is conveyed along streets and parking areas in one of two ways, either (a) in an open
_ drainage channel located in the right of way, or (b) in an enclosed storm drain located under
the street or right of way. The use of an open channel or storm drain in a particular street is
determined by a number of factors, such as drainage area, slope, length, housing density, and
street type. Open channels can be used on smaller streets, but at some point runoff velocities
become too erosive to be adequately handled in an earthen channel and they must be enclosed
in a storm drain. This erosive velocity is typically around 4 feet per second. A channel's
maximum velocity is generally defined and computed using the peak discharge rate under the
two year design storm event.
Open vegetated channels can have many water resource protection benefits. For example, a
portion of stormwater pollutants may be removed through grass and soil as they pass through
the channel. Performance monitoring has shown that open channels only realize these
benefits under ideal conditions (e.g., low slope, sandy soils, dense grass cover, etc.). When
these conditions are not met, drainage channels can have a low or even negative removal
capability for many pollutants.
Only recently have engineers recognized the value of designing open channels explicitly for
pollutant removal during small and moderate -sized storm events. Depending on the depth to
the water table, they are known as either grass channels, dry swales or wet swales.
Checkdams, underdrains, stone inlets, prepared soil mixes and landscaping are also used to
enhance the pollutant removal capability of swales. The use of grass channels or swales along
., residential streets can be an economical and effective element of a BMP system, as long as the
critical erosive velocity is not exceeded. In addition, open channels must be designed to
prevent standing water, to ensure that mowing is convenient, and to avoid odors, mosquitoes,
or other nuisances associated with standing water.
Even the moderate vertical break of a curb shelters airborne pollutants that blow in by the
wind. Thus, dust, pollen, leaves, grass clippings, and other nitrogen -rich organic matter can
be trapped by the curb, where they remain until they are washed into the storm drain system.
_. Some management strategies that may contribute to a reduction in urban nitrogen from
roadside drainage systems are:
71

• Minimize the use of curb and gutter and maximize the use of vegetated swales where
feasible.
• If curb and gutter is necessary, consider frequent curb cuts to divert manageable quantities
of runoff into stable vegetated areas for infiltration. (Land of Sky 1995).
• Develop a site/landscaping plan that uses landscaped areas for infiltration or
detention/retention areas (bioretention).
• Instead of grass that requires chemical applications, use trees. shrubs, ground cover,
mulch or other materials that require little or no chemical applications.
Allowing Cluster or Open -Space Developments
Cluster or open -space developments rearrange density on each development tract so that a
lower percentage of the tract is covered by impervious surfaces. This results in more land
being retained in a natural state.
This approach respects private property rights and the ability of developers to create new
homes for the expanding population. Such developments are "density -neutral" since the
overall number of dwellings allowed is not less than it would be in a conventional
development. This lessens the adverse impact on the remaining natural areas and cultural
resources that make our communities such special places to live, work, and recreate.
The most important step in designing an "open space subdivision" is to identify the land to
preserve. "Primary Conservation Areas" include unbuildable wetlands, waterbodies, _
floodplains, and steep slopes. "Secondary Conservation Areas" include mature woodlands,
upland buffers around wetlands and waterbodies, prime farmland, natural meadows, critical
wildlife habitats, and sites of historic, cultural or archeological significance.
Cluster developments can reduce road lengths by 50 to 70 percent (Arendt 1993). At an
average cost of over $100 to construct a linear foot of road, such reductions are extremely
cost-effective. The reduction in road length may also reduce the overall capital costs for
stormwater controls. The developer may realize a significant savings in the reduced need for
storm drain pipes and best management practices. It has been reported that in some cases the
overall reduction in capital costs associated with these developments can be 10 to 33 percent
(Schueler 1995). _
Property owners can realize indirect economic benefits from reduced impervious cover. While
a host of factors influence future residential property values, some evidence indicates that
homes located adjacent to well designed and maintained open or green space do appreciate at
a faster rate than traditional subdivision properties. This premium has been found to range
from 5 to 32 percent, according to Land Ethics (1994). Another study in Massachusetts _
indicated that homes in cluster subdivisions with open space appreciated 13% more in value
than similar homes in conventional subdivisions over a 21-year period (Arendt 1993).
72

For local governments, it is typically more expensive to provide public services on large
residential lot developments compared to smaller ones. Clustered developments can greatly
reduce the length of water and sewer pipes and roads that local governments have to construct
and maintain.
AIlowin.g Traditional Neighborhood Developments
Traditional neighborhood developments (TNDs) are designed so that dwellings, shops, and
workplaces are in close proximity. They typically follow a rectilinear pattern of streets and
blocks arranged to provide interesting routes of travel that also accommodate and promote
pedestrian travel and bicycle travel rather than automobile travel. These developments also
-- include greenways, landscaped streets, churches, stores, schools, and parks woven into the
neighborhood for social activity, recreation, aesthetics, and environmental enhancement. See
Figure G1 for a diagram of a TND.
One of the most important features of TNDs that affects water quality is their compactness.
As these developments expand, they maintain their compact, rectilinear layout and their
accessibility. Another environmental advantage offered by TNDs is that they may reduce
automobile traffic and promote increased use of alternative forms of transportation, such as
mass transit.
Environmental impacts of TNDs are affected by site conditions and the development intensity
and design. Those TNDs that offer environmental benefits may also offer economic benefits.
The increased value of real estate in a traditional development is illustrated in Raleigh. The
"inside the beltline" neighborhoods in Raleigh that have city blocks, greenways, and
accessibility to shopping areas, on the average, sell for 40 percent more per square foot than
homes in North Raleigh subdivisions (pers. comm. Marilyn Marks, Simpson and Underwood
Realtors, 1997).
Other Techniques
In many instances, subdivision codes contain rigid requirements that govern setbacks from the
property lines. These requirements increase the length of driveways, roads, and sidewalks
and thus increase the proportion of impervious cover to housing units. These requirements
can inadvertently increase impervious surfaces and cause expense for developers and
homeowners.
Large -lot zoning also impacts overall imperviousness. Although large -lot zoning reduces
rooftop impervious cover in a watershed and spreads development over a wider geographic
area, it can increase transport -related impervious cover because of longer road networks.
Although large -lot zoning may be wise for individual sensitive watersheds, it is probably not
practical as a uniform standard. An alternative is forming more compact neighborhoods in
_ order to decrease impervious surfaces associated with transportation, a factor that has long
been overlooked. Another advantage to compact neighborhoods is that they decrease
automobile use by allowing better accessibility for walkers and cyclists and facilitating public
transportation.
73

Figure G1. Maytown Before and After (adapted from Stimmel Associates, 1993)
A. Maytown in 1900 B. Maytown today. C. Maytown as it could have been.
A. Maytown developed around
B, The development that has occurred
C. The same amound of development
a central square with a grid street
over the past 30 years is not
could have been accommodated in a
pattern. Development was compact
compatible with the original village.
pattern that complements the original
and there was a distinct separation
Curvilinear street and cul-de-sacs
village. All residents could have been
between the village and the
have replaced the traditional grid
within walking distance of the center
surrounding countryside.
street pattern. The separation between
square, community facilities, and
the village and the surrounding
parks
countryside have been lost.
74

Appendix L. Ordinance Establishing
Stormwater Nutrient Management
Requirements for New Development
75

Chapter 8. Stormwater Management
Section 801. Soil Erosion and Sedimentation Control.
A Purpose.
This section is adopted for the purposes of: ._
1. Regulating certain land -disturbing activity to control accelerated erosion and sedimentation in order to
prevent the pollution of water and other damage to lakes, watercourses, and other public and private
property by sedimentation; and
2. Establishing procedures through which these purposes can be fulfilled.
B General.
1. Soil disturbance shall be conducted in such a manner as to minimize erosion. Soil stabilization shall
consider the time of year, site conditions, and the use of temporary and permanent measures.
2. Properties and channels located downstream from development sites shall be protected from erosion and
sedimentation. At point where concentrated flow leaves a site, stable downstream facilities are required.
3. Soil erosion and sediment control features shall be constructed prior to the commencement of upland
disturbance.
4. If dewatering devices are used, adjacent properties shall be protected. Discharges shall enter an effective
sediment and erosion control measure. --
5. For detached single-family residential development occumng one lot at a time, alternative to the standards
of this section may be approved by the Director of Engineering.
C Soil Stabilization.
1. Temporary soil stabilization shall be applied to disturbed areas within fourteen (14) days of the end of soil
disturbance to all areas that will not be final graded and stabilized within forty-five (45) days.
2. Permanent stabilization shall be done within fourteen (14) days of final grading of the soil. Permanent soil
stabilization measures shall be applied to channels (including bed and banks) within fourteen (14) days of
the end of primary disturbance of the channel.
3. Permanent or temporary vegetation shall not be considered established until sufficient ground cover is
mature enough to control erosion.
4. Earthen embankments shall be constructed with side slopes with a vertical to horizontal ratio no steeper
than one to 3 (1: 3).
D Disturbed Areas.
1. Disturbed areas draining more than one (1) but fewer than five (5) acres shall be protected by a sediment
trap or equivalent control measure at a point down slope of the disturbed area.
2. Disturbed areas draining more that five (5) acres shall be protected by a sediment basin or equivalent -�
control measure at a point down slope of the disturbed area.
E Sediment Control.
1. All storm sewer facilities that are or will be functioning during construction shall be protected, filtered or .�
otherwise treated to remove sediment.
2. A stabilized mat or aggregate underlain with filter cloth shall be located at any point where traffic will be
entering or leaving a construction site to or from a public right-of-way, street, alley or parking area.
F Removal of Temporary Measures.
All temporary erosion and sediment control measures shall be removed within 30 days after final site stabilization is
achieved or after temporary measures are no longer needed. Trapped sediment and other disturbed soil areas
shall be permanently stabilized.
G Scope and Exclusions.
This Section shall not apply to the following land -disturbing activities:
1. Activities, including breeding and grazing of livestock, on agricultural land for the production of plants and animals
useful to man, including, but not limited to:
a. Forage and sod crops, grain and feed crops, tobacco, cotton, and peanuts.
b. Dairy animals and dairy products.
76

C. Poultry and poultry products.
d. Livestock, including beef cattle, sheep, swine, horses, ponies, mules, and goats.
e. Bees and apiary products.
f. Fur producing animals.
2. Activities undertaken on forestland for the production and harvesting of timber and timber products and
— conducted in accordance with best management practices set out in Forest Practice Guidelines Related to
Water Quality, as adopted by the North Carolina Department of Environment, and Natural Resources. If
land -disturbing activity undertaken on forest land for the production and harvesting of timber and timber
products is not conducted in accordance with Forest Practice Guidelines Related to Water Quality, the
provisions of this Section shall apply to such activity and any related land -disturbing activity on the tract;
and
3. Activities for which a permit is required under the Mining Act of 1971, Article 7 of Chapter 74 of the
General Statutes; and
4. Land disturbing activity over which the State has exclusive regulatory jurisdiction as provided in G.S.
113A-56(a); and
5. For the duration of an Emergency, activities essential to protect human life.
H General Requirements.
1. Plan Required. No person shall initiate any land -disturbing activity which uncovers more than one acre
without having an erosion control plan approved by the City.
2. Protection of Property. Persons conducting land -disturbing activity shall take all reasonable measures to
protect all public and private property from damage caused by such activity.
3. More Restrictive Rules Shall Apply. Whenever conflicts exist between Federal, State, or local laws, or
rules, the more restrictive provision shall apply.
I Basic Control Objectives.
An erosion and sedimentation control plan may be disapproved pursuant to this section if the plan fails to address
the following control objectives:
1. Identify Critical Areas. On -site areas which are subject to severe erosion, and off -site areas which are
w„ especially vulnerable to damage from erosion and/or sedimentation, are to be identified and receive
special attention.
2. Limit Time of Exposure. All land -disturbing activities are to be planned and conducted to limit exposure
to the shortest feasible time.
3. Limit Exposed Areas. All land -disturbing activity is to be planned and conducted to minimize the size of
the area to be exposed at any one time.
4. Control Surface Water. Surface water runoff originating upgrade of exposed areas should be controlled
to reduce erosion and sediment loss during the period of exposure.
5. Control Sedimentation. All land -disturbing activity is to be planned and conducted so as to prevent off -
site sedimentation damage.
6. Manage Stormwater Runoff. When the increase in the velocity of stormwater runoff resulting from a land -
disturbing activity is sufficient to cause accelerated erosion of the receiving watercourse, plans are to
include measures to control the velocity to the point of discharge so as to minimize accelerated erosion of
.. the site and increased sedimentation of the stream.
J Mandatory Standards for Land -disturbing Activity.
No land -disturbing activity subject to the control of this Section shall be undertaken except in accordance with the
following mandatory standards:
1. Buffer Zone.
a. No land -disturbing activity during periods of construction or improvement to land shall be
permitted in proximity to a lake or natural watercourse unless a buffer zone is provided along the
margin of the watercourse of sufficient width to confine visible siltation within the twenty-five (25)
percent of the buffer zone nearest the land -disturbing activity. Waters that have been classified
as trout waters by the Environmental Management Commission shall have an undisturbed buffer
^ zone twenty-five (25) feet wide or of sufficient width to confine visible siltation within the twenty-
.. 77

five (25) percent of the buffer zone nearest the land -disturbing activity, whichever is greater.
Provided, however, that the City may approve plans which include land -disturbing activity along
trout waters when the duration of said disturbance would be temporary and the extent of said
disturbance would be minimal. This subdivision shall not apply to a land -disturbing activity in
connection with the construction of facilities to be located on, over, or under a lake or natural
watercourse.
b. Approved plans assume, where applicable, compliance with the Federal and State water quality
laws, rules and regulations.
C. A plan may be disapproved if implementation of the plan would result in a violation of rules
adopted by the Environmental Management Commission.
d. Unless otherwise provided, the width of a buffer zone is measured from the edge of the water to
the nearest edge of the disturbed area, with the twenty-five (25) percent of the strip nearer the
land -disturbing activity containing natural or artificial means of confining visible siltation.
e. The twenty-five (25) foot minimum width for an undisturbed buffer zone adjacent to designated
trout waters shall be measured horizontally from the top of the bank.
f. Where a temporary and minimal disturbance has been permitted as an exception of this Section, --
land-disturbing activities in the buffer zone adjacent to designated trout waters shall be limited to
a maximum of ten (10) percent of the total length of the buffer zone within the tract to be
distributed such that there is not more than one hundred (100) linear feet of disturbance in each
one thousand (1000) linear feet of buffer zone. Larger areas may be disturbed with the written
approval of the Director, NC Division of Land Resources.
g. No land -disturbing activity shall be undertaken within a buffer zone adjacent to ._
designated trout waters that will cause adverse temperature fluctuations in these waters,
and, as set forth in 15 NCAC 2B.0211 "Fresh Surface Water Classification and
Standards."
2. Graded Slopes and Fills. The angle for graded slopes and fills shall be no greater than the angle which
can be retained by vegetative cover or other adequate erosion control devices or structures and which can
be demonstrated to be stable. Stable is the condition where the soil remains in its original configuration,
with or without mechanical constraints. In any event, slopes left exposed will, within fifteen (15) working
days or thirty (30) calendar days of completion of any phase of grading, whichever period is shorter, be
planted or otherwise provided with ground cover, devices, or structures sufficient to restrain erosion
pursuant to GS §113-A-57 (2).
3. Fill Material. Unless a permit from the N.C. Department of Environment and Natural Resources Division
of Solid Waste Management to operate a landfill is on file for the official site, acceptable fill material shall
be free of organic or other degradable materials, masonry, concrete and brick in sizes exceeding twelve —�
(12) inches, and any materials which would cause the site to be regulated or a Iandfili by the State of North
Carolina.
4. Ground Cover. Whenever land -disturbing activity is undertaken on a tract comprising more than one acre, if more than one acre is uncovered, the person conducting the land -disturbing activity shall install such
sedimentation and erosion control devices and practices as are sufficient to retain the sediment generated
by the land -disturbing activity within the boundaries of the tract during construction upon and development
of said tract, and shall plant or otherwise provide a permanent ground cover sufficient to restrain erosion
after completion of construction or development. Except as provided otherwise in this Section, provisions
for a ground cover sufficient to restrain erosion must be accomplished within fifteen (15) working days or
ninety (90) calendar days following completion of construction or development whichever period is shorter.
5. Prior Plan Approval. No person shall initiate any land -disturbing activity on a tract if more than one acre
is to be uncovered unless, thirty or more days prior to initiating the activity, an erosion and sedimentation
control plan for such activity is filed with and approved by the City.
78

K Design and Performance Standards.
1. Except as provided otherwise in this Section erosion and sedimentation control measures, structures, and
devices shall be so planned, designed, and constructed as to provide protection from the calculated
maximum peak rate of runoff from the ten (10) year storm. Runoff rates shall be calculated using the
procedures in the USDA, Soil Conservation Service's "National Engineering Field Manual for Conservation
-- Practices", or other acceptable calculation procedures.
2. In High Quality Water (HQW) zones the following design standards shall apply:
a. Uncovered areas in HQW zones shall be limited at any time to a maximum total area of twenty
(20) acres within the boundaries of the tract. Only the portion of the land -disturbing activity within
a HQW zone shall be governed by this section. Larger areas may be uncovered within the
boundaries of the tract with the written approval of the Director, NC Division of Land Resources.
b. Erosion and sedimentation control measures, structures, and devices within HQW zones shall be
so planned, designed and constructed to provide protection from the run off of the twenty-five
year storm which produces the maximum peak rate of run off as calculated according to
procedures in the United States Department of Agriculture Soil Conservation Service's "National
Engineering Field Manual for Conservation Practices" or according to procedures adopted by any
other agency of this State or the United States or any generally recognized organization or
association.
C. Sediment basins within HQW zones shall be designed and constructed such that the basin will
have a settling efficiency of at least seventy percent (70%) for the forty (40) micron (0.04 mm)
size soil particle transported into the basin by the runoff of that two (2) year storm which produces
the maximum peak rate of runoff as calculated according to procedures in the United States
Department of Agriculture Soil Conservation Service's "National Engineering Field Manual for
Conservation Practices" or according to procedures adopted by any other agency of this State or
w., the United States or any generally recognized organization or association.
d. Newly constructed open channels in HQW zones shall be designed and constructed with side
slopes no steeper than two horizontal to one vertical (2:1) if a vegetative cover is used for
stabilization unless soil conditions permit a steeper slope or where the slopes are stabilized by
., using mechanical devices, structural devices or other acceptable ditch liners. In any event, the
angle for side slopes shall be sufficient to restrain accelerated erosion.
e. Ground cover sufficient to restrain erosion must be provided for any portion of a land -disturbing
activity in a HQW zone within fifteen (15) working days or sixty (60) calendar days following
completion of construction or development, whichever period is shorter.
L Stormwater Outlet Protection; Permanent Downstream Protection of Stream Banks, Channels, Conduits
-- and Slopes.
1. Intent. Stream banks and channels downstream from any land disturbing activity shall be protected from
increased degradation by accelerated erosion caused by increased velocity of runoff from the land
disturbing activity.
2. Performance Standard. Persons shall conduct land -disturbing activity so that the post construction
velocity of the ten (10) year storm runoff in the receiving watercourse to the discharge point does not
�., exceed the greater of:
a. The velocity established by the Table 8-1 of this section; or
b. The velocity of the ten (10) year storm runoff in the receiving watercourse prior to development.
If conditions (1) or (2) of this Paragraph cannot be met, then the receiving watercourse to and
including the discharge point shall be designed and constructed to withstand the expected
velocity anywhere the velocity exceeds the "prior to development" velocity by ten percent (10%.)
3. Acceptable Management Measures. Measures applied alone or in combination to satisfy the intent of
this section are acceptable if there are no objectionable secondary consequences. The Commission
recognizes that management of stormwater runoff to minimize or control downstream channel and bank
erosion is a developing technology. Innovative techniques and ideas will be considered and may be used
79

when shown to have potential to produce successful results. Some alternatives, while not exhaustive, are
to:
a. Avoid increases in surface runoff volume and velocity by including measures to promote
infiltration to compensate for increased runoff from areas rendered impervious;
b. Avoid increases in stormwater discharge velocities by using vegetated or roughened swales and
waterways in lieu of closed drains and high velocity paved sections;
C. Provide energy dissipaters at outlets of storm drainage facilities to reduce flow velocities
to the point of discharge. These may range from simple rip -rapped sections to
complex structures;
d. Protect watercourses subject to accelerated erosion by improving cross sections and/or providing
erosion -resistant lining; and
e. Upgrade or replace the receiving device structure, or watercourse such that it will receive and
conduct the flow to a point where it is no longer subject to degradation from the increased rate of
flow or increased velocity.
4. Exceptions. This rule shall not apply where it can be demonstrated that stormwater discharge velocities
will not create an erosion problem in the receiving watercourse.
5. Velocity. The following is a table for maximum permissible velocity for stormwater discharges:
Table 8-1. Maximum Permissible Velocities.
Source - Adapted from recommendations by Special Committee on Irrigation Research, American
Society of Civil Engineers, 1926, for channels with straight alignment. For sinuous channels, multiply
allowable velocity by 0.95 for slightly sinuous, by 0. 9 for moderately sinuous channels, and by 0.8 for •—
highly sinuous channels.
M Borrow and Waste Areas. When the person conducting the land -disturbing activity is also the person conducting the borrow or waste disposal
activity, areas from which Morrow is obtained and which are not regulated by the provisions of the Mining Act of
1971, and waste areas for surplus materials other than landfills regulated by the Departments Division of Solid
Waste Management shall be considered as part of the land -disturbing activity where the borrow material is being
used or from which the waste material originated. When the person conducting the land -disturbing activity is not
the person obtaining the borrow permit and/or disposing of the waste, these areas shall be considered a separate
land -disturbing activity.
N Access and Haul Roads.
Temporary access and haul roads, other than public roads, constructed or used in connection with any land -
disturbing activity shall be considered a part of such activity. —
80

0 Operations in Lakes or Natural Watercourses.
Land -disturbing activity in connection with construction in, on, over, or under a lake or natural watercourse shall be
planned and conducted in such a manner as to minimize the extent and duration of disturbance of the stream
channel. The relocation of a stream, where relocation is an essential part of the proposed activity, shall be planned
and executed so as to minimize changes in the stream flow characteristics, except when justification for significant
alteration to flow characteristic is provided.
P Responsibility for Maintenance.
During the development of a site, the person conducting the land -disturbing activity shall install and maintain all
temporary and permanent erosion and sedimentation control measures as required by the approved plan or any
provision of this Section, the Act, or any order adopted pursuant to this Section or the Act. After site development,
the landowner or person in possession or control of the land shall install and/or maintain all necessary permanent
erosion and sediment control measures, except those measures installed within a road or street right-of-way or
easement accepted for maintenance by a governmental agency.
Q Additional Measures.
Whenever the City determines that significant sedimentation is occurring as a result of land -disturbing activity,
despite application and maintenance of protective practices, the person conducting the land -disturbing activity will
be required to and shall take additional protective action.
R Existing Uncovered Areas.
1. All uncovered areas existing on the effective date of this Section which resulted from land -disturbing
activity, exceeding one (1) acre, are subject to continued accelerated erosion, and are causing off -site
damage from sedimentation, shall be provided with a ground cover or other protective measures,
— structures, or devices sufficient to restrain accelerated erosion and control off -site sedimentation.
2. The City will serve upon the landowner or other person in possession or control of the land a written notice
of violation by registered or certified mail, return receipt requested, or other means. The notice will set
forth the measures needed to comply and will state the time within which such measures must be
completed. in determining the measures required and the time allowed for compliance, the authority
serving notice shall take into consideration the economic feasibility, technology, and quantity of work
required, and shall set reasonable and attainable time limits of compliance.
3. The City reserves the right to require preparation and approval of an erosion control plan in any instance
where extensive control measures are required.
4. This rule shall not require ground cover on cleared land forming the future basin of a planned reservoir.
S Permits.
1. No person shall undertake any land -disturbing activity subject to this Section without first obtaining a
permit therefore from the City except that no permit shall be required for any land -disturbing activity:
a. For the purpose of fighting fires; or
b. For the stock piling of raw or processed sand, stone, or gravel in material processing plants and
storage yards, provided that sediment control measures have been utilized to protect against off -
site damage; or
C. That does not exceed forty-three thousand five hundred sixty (43,560) square feet in surface
area. In determining the area, lands under one or diverse ownership being developed as a unit
-- will be aggregated.
2. The property owner or their agent shall submit an application for a Sediment and Erosion Control Permit to
the Department of Engineering.
3. Payment of a fee for review of the application is hereby required. The fee shall be as set from time to time
by resolution of the City Council and published in the City's Administrative Policy Manual.
4. The City may decide that a preconstruction conference is required.
5. A permit issued under this article shall be prominently displayed until all construction is complete, all
permanent sedimentation and erosion control measures are installed and the site has been stabilized.
T Erosion and Sedimentation Control Plaits.
1. An erosion control plan shall be prepared for all land -disturbing activities subject to this Section whenever
the proposed activity is to be undertaken on a tract comprising more than one acre, if more than one acre
81

is to be uncovered. The plan shall be fled with the City and a copy shall be simultaneously submitted to
the Edgecombe County or Nash County Soil and Water Conservation District as applicable, at least thirty
(30) days prior to the commencement of the proposed activity. The District shall forward to the Director of
the Division of Water Quality a copy of each erosion and sedimentation control plan for a land -disturbing
activity that involves the utilization of ditches for the purpose of de -watering or lowering the water table of
the tract, pursuant to section 2 G.S. §113A-57(4).
2. Persons conducting land -disturbing activity on a tract which covers one or more acres shall file three (3)
copies of the erosion control plan with the City at least thirty (30) days prior to beginning such activity and
shall keep another copy of the plan on file at the job site. After approving the plan, if the City either upon
review of such plan or on inspection of the job site, determines that a significant risk of accelerated erosion
or off -site sedimentation exists, the City will require a revised plan. Pending the preparation of the revised
plan, work shall cease or shall continue under conditions outlined by the appropriate authority.
3. No person may initiate a land -disturbing activity before notifying the agency that issued the plan approval
of the date that land -disturbing activity will begin.
4. Erosion control plans may be disapproved unless accompanied by an authorized Statement of Financial
Responsibility and Ownership. This statement shall be signed by the person financially responsible for the --
land-disturbing activity, or authorized agent, in fact. The Statement shall include the mailing and street
addresses of the principal place of business of the person financially responsible and of the owner of the
land or their registered agents. If the person financially responsible is not a resident of North Carolina, a _.
North Carolina agent must be designated in the Statement for the purpose of receiving notice of
compliance or non-compliance with the plan, the Act, this Section, or rules or orders adopted or issued
pursuant to this Section. --
5. The Edgecombe County or Nash County Soil and Water Conservation District as applicable shall review
the plan and submit any comments and recommendations to the City within twenty (20) days after the soil
and water conservation district received the erosion control plan, or within any shorter period of time as
may be agreed upon by the soil and water conservation district and the City. Failure of the Soil and Water
Conservation District to submit its comments and recommendations within twenty (20) days or within any
agreed -upon shorter period of time shall not delay final action on the plan.
6. The City will review each complete plan or revised plan submitted to them and within thirty (30) days of
receipt thereof will notify the person submitting the plan that it has been approved, approved with
modifications, approved with performance reservations, or disapproved. Approval assumes the
applicant's compliance with the Federal and State water quality laws, regulations and rules. Failure to
approve, approve with modifications, approve with performance reservations, or disapprove a complete
erosion and sedimentation control plan or a revised erosion control within thirty (30) days of receipt shall
be deemed approval. Disapproval of a plan or a revised plan must specifically state in writing the reasons
for disapproval. The City must approve, approve with modifications, approve with performance
reservations, or disapprove a revised plan within fifteen (15) days of receipt, or the revised submittal shall
be deemed to be approved. If, following commencement of a land -disturbing activity pursuant to an
approved plan, the City determines that the plan is inadequate to meet the requirements of this Section,
the City may require any revision of the plan that is necessary to comply with this Section. Failure to
approve, approve with modifications, approve with performance reservations, or disapprove a plan or
revised erosion control plan within fifteen (15) days of receipt shall be deemed approval of the plan.
7. A permit issued under this article shall be valid for a period not to exceed two (2) years from the date of
the approval or the time required to complete the permitted project including stabilization of all disturbed
areas, which ever is less.
8. Any plan submitted for a land -disturbing activity for which an environmental document is required by the
North Carolina Environmental Policy Act (G.S. 113A-1, et seq.) shall be deemed incomplete until a
complete environmental document is available for review. The City shall promptly notify the person
submitting the plan that the thirty (30) day time limit for review of the plan pursuant to this Section shall
not begin until a complete environmental document is available for review.
82

9. The plan required by this section shall contain architectural and engineering drawings, maps,
assumptions, calculations, and narrative statements as needed to adequately describe the proposed
�- development of the tract and the measures planned to comply with the requirements of this Section. Plan
content may vary to meet the needs of specific site requirements. Guidelines for preparation may be
obtained from the City on request.
10. A local government may disapprove an erosion control plan or draft erosion control plan where
implementation of the plan would result in a violation of the rules adopted by the Environmental
Management Commission to protect riparian buffers along surface waters, finding that an applicant, or a
parent, subsidiary, or other affiliate of the applicant:
a. Is conducting or has conducted land -disturbing activity without an approved plan, or has received
notice of violation of a plan previously approved by the Commission or a local government
pursuant to the Act and has not complied with the notice within the time specified in the notice;
b. Has failed to pay a civil penalty assessed pursuant to the Act or a local ordinance adopted
pursuant to the Act by the time the payment is due.
C. Has been convicted of a misdemeanor pursuant to G.S. 11 3A-64(b) or any criminal provision of a
local ordinance adopted pursuant to the Act or;
d. Has failed to substantially comply with State rules or local ordinances and regulations adopted
pursuant to the Act. For purposes of this subsection (i) an applicant's record may be considered
— for only the two years prior to the application date.
11. Applications for amendment of an erosion control plan in written and/or graphic form may be made at any
time under the same conditions as the original application. Until such time as said amendment is approved
by the City, the land -disturbing activity shall not proceed except in accordance with the erosion control
plan as originally approved.
12. Any person engaged in land -disturbing activity who fails to file a plan in accordance with this Section, or
who conducts a land -disturbing activity except in accordance with provisions of an approved plan shall be
deemed in violation of this Section.
13. When deemed necessary by the approving authority, a preconstruction conference may be required.
14. The approval of an erosion control plan is conditioned upon the applicant's compliance with Federal and
State water quality laws, regulations and rules pursuant to GS 11 3A-61 (b)(1).
U Appeals.
1. Except as provided in herein, the appeal of a disapproval or approval with modifications of a plan shall be
governed by the following provisions:
a. The disapproval or modification of any proposed erosion control plan by the City shall
entitle the person submitting the plan to a public hearing if such person submits written
demand for a hearing within fifteen (15) days after receipt of written notice of disapproval
or modifications.
b. Hearings held pursuant to this section shall be conducted by the Board of Adjustment within forty-
five (45) days after the date of the appeal or request for a hearing.
C. If the City upholds the disapproval or modification of a proposed soil erosion and sedimentation
control plan following the hearing, the person submitting the plan shall then be entitled to appeal
-- the local government's decision to the North Carolina Sedimentation Control Commission as
provided in Section 113A-61(c) of the General Statutes and Title 15A NCAC 4B.0018(d).
2. In the event that an erosion control plan is disapproved pursuant to this Section, the City shall notify the
Director of the Division of Land Resources of such disapproval within ten (10) days. The City shall advise
the applicant and the Director in writing as to the specific reasons that the plan was disapproved. The
applicant may appeal the City disapproval of the plan pursuant to this Section directly to the Commission.
V Inspections and Investigations.
1. Agents, officials, or other qualified persons authorized by the City will periodically inspect land -disturbing
activities to ensure compliance with the Act, this Section, or rules or orders adopted or issued pursuant to
this Section, and to determine whether the measures required in the plan are effective in controlling
83

erosion and sediment resulting from land -disturbing activity. Notice of the right to inspect shall be included
in the certificate of approval of each erosion control plan.
2. No person shall willfully resist, delay, or obstruct an authorized representative, employee, or agent of the
City while that person is inspecting or attempting to inspect a land -disturbing activity under this section.
3. If through inspection, it is determined that a person engaged in land -disturbing activity has failed to comply
with the Act, this Section, or rules, or orders adopted or issued pursuant to this Section, a notice of
violation shall be served upon that person. The notice may be served by any means authorized under GS
1A-1, Rule 4. The notice shall specify a date by which the person must comply with the Act, or this
Section, or rules, or orders adopted pursuant to this Section, and inform the person of the actions that
need to be taken to comply with the Act, this Section, or rules or orders adopted pursuant to this Section.
Any person who fails to comply within the time specified is subject to the civil and criminal penalties for a
continuing violation as provided in G.S.113A-64 provided in this Section.
4. The City shall have the power to conduct such investigation as it may reasonably deem necessary to cant' out its duties as prescribed in this Section, and for this purpose to enter at reasonable times upon any
property, public or private, for the purpose of investigating and inspecting the sites of any land -disturbing
activity. --
5. The City shall also have the power to require written statements, or filing of reports under oath, with
respect to pertinent questions relating to land -disturbing activity.
W Penalties.
1. Civil Penalties
a. Any person who violates any of the provisions of this Section, or rules or orders adopted or
issued pursuant to this Section, or who initiates or continues a land -disturbing activity for which
an erosion control plan is required except in accordance with the terms, conditions, and
provisions of an approved plan, shall be subject to a five thousand ($5,000) dollar civil penalty.
For a violation, the maximum amount that the City may assess a person is a civil penalty of up to
five thousand dollars ($5,000.00). A civil penalty may be assessed from the date of service of the
violation. Each day of a continuing violation shall constitute a separate violation.
b. Any person who violates any of the provisions of this Section, or rules or orders adopted or
issued pursuant to this Section, or who initiates or continues a land -disturbing activity; or who --
fails to acquire an approved erosion control plan shall also be subject to a single five thousand
($5,000) dollar civil penalty.
C. The Director of Engineering or designee of the City shall determine the amount of the civil penalty —
to be assessed under this subsection and shall notify the person who is assessed the civil
penalty of the amount of the penalty and the reason for assessing the penalty. In determining the
amount of the penalty the Director of Engineering or designee shall consider the degree and
extent of harm caused by the violation and the cost of rectifying the damage, the amount of
money the violator saved by noncompliance, whether the violation was committed willfully, and
the prior record of the violator in complying or failing to comply with this Section. The notice of
assessment shall be served by any means authorized under this Section, and shall direct the
violator to either pay the assessment or contest the assessment, within thirty (30) days after
receipt of the notice of assessment, by written demand for a hearing.
d. A hearing on a civil penalty shall be conducted by the City Manager or his designee within thirty
(30) days after the date of the written demand for the hearing. The City Manager shall make a
decision within fifteen (15) days after the date of the hearing. Appeals from the City Manager's
decision will be forwarded to the Board of Adjustment, and the Board of Adjustment shall render its final decision on the civil penalty within fifteen (45) days of the receipt of the appeal request.
Appeal from the final decision of the City Council shall be to the Superior Court of the County
where the violation occurred, or the location of the violator's residence or principal place of ..
business.
e. If payment is not received or equitable settlement reached within thirty (30) days after demand for
payment is made, the matter shall be referred to the City Attorney for institution of a civil action in
84

the name of the City, in the appropriate division of the general courts of justice for recovery of the
penalty. Such civil actions must be filed within three (3) years of the date the assessment was
due. An assessment that is not contested is due when the violator is served with a notice of
assessment. An assessment that is contested is due at the conclusion of the administrative and
judicial review of the assessment.
f. In determining the amount of the penalty the City Council shall consider the degree and extent of
harm caused by the violation, the cost of rectifying the damage, the amount of money the violator
saved by non-compliance, whether the violation was committed willfully and the prior record of
�. the violator in complying or failing to comply with the Article.
g. Civil penalties collected pursuant to this Section shall be credited to the general fund of the local
government as non -tax revenue.
h. Criminal Penalties: Any person who knowingly or willfully violates any provision of this Section, or
^ rule or order adopted or issued pursuant to this Section, or who knowingly or willfully initiates or
continues a land -disturbing activity for which an erosion control plan is required except in
accordance with the terms, conditions, and provisions of an approved plan, shall be guilty of a
^" Class 2 misdemeanor which may include a fine not to exceed five thousand ($5,000) dollars as
provided in G.S. §113A-64.
X Injunctive Relief.
1. Whenever the City Council has reasonable cause to believe that any person is violating or threatening to
violate this Section or any rule or order adopted or issued pursuant to this Section, or any term,
condition, or provision of an approved erosion control plan, it may, either before or after the institution of
any other action or proceeding authorized by this Section, institute a civil action in the name of the City for
injunctive relief to restrain the violation or threatened violation. The action shall be brought in the Superior
Court of Edgecombe or Nash County as appropriate.
., 2. Upon determination by a court that an alleged violation is occurring or is threatened, the court shall enter
any order or judgment that is necessary to abate the violation, to ensure that restoration is performed, or
to prevent the threatened violation. The institution of an action for injunctive relief under this section shall
not relieve any party to the proceedings from any civil or criminal penalty prescribed for violations of this
Section.
Y Restoration of Areas Affected by Failure to Comply.
The City may require a person who engaged in a land -disturbing activity and failed to retain sediment generated by
r. the activity, as required by G.S.113A-57(3), to restore the waters and land affected by the failure so as to minimize
the detrimental effects of the resulting pollution by sedimentation. This authority is in addition to any other civil or
criminal penalty or injunctive relief authorized under this Section.
85

Section 802 Tar -Pamlico Stormwater Nutrient Management Requirements
The Legislature of the State of North Carolina has designated specific local governments in the Tar Pamlico River Basin and
has required them to develop stonnwater management program in conformance with 15A NCAC 2B.0258, Tar -Pamlico
River Basin -!Nutrient Sensitive Waters Management Strategy. This section is adopted pursuant to the authority contained in
Article 19 of Chapter 160A, Planning and Development and the requirements of 15A NCAC 2B.0258. Any modifications to
this section are subject to the approval by the NC Division of Water Quality (DWQ). --
A Applicability
1. The provisions of this section shall apply within the corporate limits of the City of Rocky Mount and the
ETJ, as defined in section 205 of this LDC.
2. All land development activity meeting the criteria listed below must comply with the requirements of this
section.
a. Any activity that disturbs greater than one acre of land to establish, expand, or replace a single
family or duplex residential development or recreational facility. For individual single family
residential lots of record that are not part of a larger common plan of development or sale, the
activity must also result in greater than ten percent built -upon area.
b. Any activity that disturbs more than one half (112) acre of land in order to establish, expand or
modify a multi -family residential development or a commercial, industrial, institutional or any other
non-residential facility.
B Exceptions
1. Projects meeting the criteria listed in 802.A.2.a-c that replace or expand existing structures or
improvements and that do not result in a net increase in built -upon area are not required to comply with
the provisions of this section. ^
2. Projects meeting the criteria listed in 802.A.2.a-c that are located within an area that the City Council has
designated as a redevelopment area will not be required to achieve nutrient reductions provided the City
has a specific redevelopment strategy in place for the area that addresses the following: --
a. The redevelopment area is a historic community center, traditional central business district,
historical district, educational center or other existing developed area specifically designated by
the City Council.
b, The City has an established strategy for reinvestment in the area as appropriate including one or
more of the following:
1) A "fix it first" policy that reserves public funds for repair of existing infrastructure in these
areas before investing in new infrastructure of the same type in new growth areas.
2) Mixed uselmixed density zoning provisions
3) Retrofits that are consistent with NC DOT definition for pedestrian scale in traditional
neighborhood developments.
4) Parking maximums or shared parking ratios
5) Residential density bonuses where parking maximums, pedestrian scale, or "fix it first"
are considered.
6) The redevelopment plan is conducive to the goals of the Tar Pamlico Nutrient
Management Strategy.
3. Projects that replace or expand existing structures or improvements resulting in a net increase in built .�
upon area shall achieve a 30 percent reduction in nitrogen loading and no increase in phosphorus loading
relative to the previous development. Such projects may achieve these loads through onsite or offsite
measures or some combination thereof. ^
4. Phased residential or commercial projects with multiple lots that propose shared stormwater facilities may
be permitted as "on -site" facilities not subject to the pre-treatment limitations defined section 802 F of this
LDC, provided the shared facility is designed and constructed to meet the nutrient reduction and
^
attenuation requirements for the entire project.
C Exemptions
Agriculture, mining or forestry activities are not subject to the new development requirements of this section.
86

D Protection of Riparian Buffers
1. Establishment and Protection of Riparian Buffers,
�- New developments meeting the criteria listed in section 802 A, must protect areas adjacent to intermittent
and perennial streams in accordance with the Tar Pamlico Riparian Buffer Rule. A fifty (50) ft. wide
riparian buffer is established on all sides of intermittent and perennial streams, ponds, and lakes shown on
.� the most recent version of either a Natural Resources Conservation Service Soil Survey of Nash County
and Soil Survey of Edgecombe County or a 1:24,000 scale (7.5 minute quadrangle) topographic map
prepared by the U. S. Geological Survey (USGS). Tar Pamlico riparian buffers must be shown on all
development plans, preliminary plats and final plats that contain land area within 50 of a intermittent or
perennial stream. If the plan or plat shows an encroachment into the riparian buffer, approval from the
DWQ must accompany the submittal. The City will not approve new development plans that include land
area within 50 feet of the banks of a regulated water body except where one of the following conditions:
a. The development plan does not propose to impact the riparian buffer or,
b. The property owner has received approval from the Division of Water Quality (DWQ) of the North
Carolina Department of Environment and Natural Resources. Approval by the DWQ may be in
the form of the following:
1) An on -site determination by the DWQ in writing that regulated surface waters are not
present on the site.
2) A permit for the proposed construction activity.
3) An authorization certificate and approval on a mitigation plan for a use designated as
allowable with mitigation
.. 4) A variance from DWQ and/or the Environmental Management Commission.
E Nutrient Reduction Requirements
1. Nitrogen and Phosphorus Export Standards
a. All new development meeting the criteria listed in 802.A must limit nitrogen export to 4.0 pounds
per acre per year (Ibs/actyr) and phosphorus export to 0. 4 pounds per acre per year (lbs/ac/yr)
through some combination of the following
1) Construction of allowable onsite or offsite stormwater management facilities. Use of
offsite facilities is subject to the provisions of 802 F-G.
2) Participation in an approved "regional" or "jurisdiction -wide" facility or strategy.
3) Dedication of "open space" and/or "conservation" easements. Easements may be
onsite or offsite subject to the provisions listed in section 802 F-G and section 804 of
this LDC. Offsite land conservation offsets that drain to the same classified water as the
new development and meet the criteria specified in 802 G.2.b may be approved by the
Director of Engineering or designee.
2. Calculation of Nitrogen and Phosphorus Export and Removal Efficiencies
a. The nitrogen and phosphorus export from all new development meeting the criteria listed in
.. 803.A must be calculated in pounds per acre per year (Iblaclyr). The export values for various
types of land use, BMP removal efficiencies and the methodologies to be used in calculating the
nitrogen and phosphorus export from the development are specified in the "City of Rocky Mount
Standard Specifications and Design Manual" and/or the "Tar -Pamlico River Basin: Stormwater
Program for Nutrient Control." These standards and all revisions thereto are hereby adopted by
reference.
3. Allowable Best Management Practices for Nitrogen and Phosphorus Reduction
a. All stormwater management and/or BMP facilities must designed in accordance with section 804
of this LDC.
b. Allowable BMPs for Nitrogen and/or Phosphorus reduction may include but are not limited to the
following:
1) Wet detention ponds
2) Constructed wetlands
—3) Restored riparian buffers
87

4) Grass swales
5) Vegetative filter strips with level spreaders
6) Bioretention �.
7) Sand Filters
8) Proprietary BMP or other BMPs (subject to approval by the Director of Engineering and
DWQ)
C. Specific use of any particular device or strategy is subject to the approval by Director of
Engineering.
F Peak Runoff Control
1. No net increase in peak stormwater runoff
New development shall not result in an increase in peak stormwater runoff flow leaving the site from the
pre -development conditions for the 1-year 24-hour, 10-year 24-hour and the 25-year 24-hour storm
events.
2. Calculation Methods
Calculation Methods shall be in accordance with the standards specified in section 804 of this LDC.
3. Exceptions to the peak flow requirement
Peak flow control is not required for new developments that meet one or more of the flowing requirements:
a. The overall impervious surface area is less than fifteen (15) percent of the total site and the
remaining pervious portions of the site are utilized to the maximum extent practical to convey and
control the stormwater runoff, and;
b. The increase in peak flow between the pre -development and post -development conditions does
not exceed ten (10) percent, or;
C. The Director of Engineering makes a determination that stormwater detention at this particular
location will increase flooding, accelerate erosion or negatively impact existing drainage problems
in the area. In such cases, an alternate method of peak attenuation management may be
required.
G Offsite Partial Offset Option
The Tar -Pamlico stormwater rule provides the option to offset nutrient load increases from new development by
providing treatment of offsite areas. In order for a project to use the partial offsite offset option, the development
plan and offsite facility must meet the following conditions:
1. Except where the project is participating an approved jurisdiction wide facility or approach, as defined in
section 802 G, the new development must first reduce nitrogen export from the site as follows:
a. Single-family or duplex residential meeting the criteria in 802 A.2.a must limit nitrogen export to
no more than 6 lb Nlac-yr.
b. Development meeting the criteria in 802 A.2.b must limit nitrogen export to 10 lb Nlac-yr.
2. The balance of the nitrogen reduction, to 4 lb N/ac-yr, must be made by an offsite facility.
3. The offsite area must drain to the same classified surface water as the new development, as defined in the
schedule of Classifications, 15A NCAC 2B .0316 and listed in Table 8-2 of this chapter, or be a part of a
jurisdiction -wide facility or approach approved by DWQ as defined in section 802 G of this LDC.
4. The net phosphorus loading for the project must be reduced to 0.4 lblaclyr. Some or all of the reduction
may be obtained through the offsite facility.
5. The offsite facility may only be used to address only the nutrient requirements, except where the ^'
development proposal provides supporting calculations, approved by Director of Engineering or designee,
that demonstrate that meeting some or all attenuation requirements offsite will not result in degradation of
the classified surface waters to which the new development site discharges.
6. The off -site stormwater management and/or BMP facility may serve multiple projects provided the facility
is appropriately sized and has an tracking system approved by the Director of Engineering to allocate
nutrient removal and flow attenuation to the participating development sites.
7. The development owner and the owner of the offsite facility, if different from the development owner, must
provide a recoded enforceable agreement stating that offsite facilities are dedicated to achieving the
specified nutrient and flow reductions for the life of the new development. The responsibility for .�
88

maintaining these reductions as well as the provisions of any easements and operation and maintenance
agreements required in accordance with section 804 of this LDC shall run with the land and be binding
upon subsequent owners of both the development project and the offsite facility.
8. Operation and maintenance plans and easements must be provided for all onsite and offsite facilities in
accordance with the provisions of section 804 of this LDC.
^
Table 8-2: Tar River Basin Classified Surface Waters
Receiving Stream Name
Stream Segment
Water Quali Classification
Tar River
4000' upstream of reservoir dam to dam
WS-IV, NSW, CA, 28-64
Tar River
Reservoir dam to Maple Creek
WS-IV, NSW 28-64.5
Grape Branch
Source to Tar River
WS-IV, NSW 2M5
-Maple Creek
Source to Tar River i
WSAV, NSW 28-66
Tar River
Maple Creek to 100' downstream of old
CRM intake of HWY 64
WS-IV, NSW 28-66.5
Tar River
CRM intake to RM Mills Dam
B. NSW 28-67
Stoney Creek
Source to Tar River
C, NSW 28-68
'far River
RM Mills dam to 0.9 mi downstream Buck
Swam
WS-IV, NSW 28-69
Goose Branch
Source to Tar River
C, NSW 28-70
Cowlick Branch
Source to Tar River
C, NSW 28-71
Compass Creek
Source to Tar River
C, NSW 28-72
Hombeam Branch
Source to Compass Creek
C, NSW 28-72-1
Gay branch Indian Branch
Source to Tar River
C, NSW 28-72.5
Buck Swamp
Source to Tar River
C, NSW 28-73
Beech Branch
Source to Hwy 301
B, NSW 28-75 1
Beech Branch
Hwy 301 to Falling Run
C, NSW 28-75 2
Little Cokey Swamp
Source to Cokey Swamp
C, NSW 28-83-3-1
^ H Regional and Jurisdiction -wide Facilities and Strategies
The Tar -Pamlico stormwater rule provides the option for local govemments to develop regional or jurisdiction -wide
stormwater facilities and/or approaches as an altemative means for addressing nutrient or flow control
requirements. Regional or jurisdiction -wide approaches will be undertaken by the City on a project -by -project basis
and will be incorporated into the City's comprehensive stormwater management program as they are developed
and approved by DWQ.
1. Regional Facilities
'- a. Regional Facility within the context of this section means a stormwater management facility or
approach that provides a portion of the nutrient and/or flow control requirements for multiple
developments in a specified area within the City's jurisdiction. Examples of regional facilities may
-- include but are not limited to wet detention ponds or constructed wetlands.
b. Regional facilities may be publicly or privately owned and operated, but must be approved by
DWQ if the facility is proposed to serve more than one classified stormwater basin.
2. Jurisdiction -wide Approach
a. Jurisdiction -Wide Approach within the context of this section means a nutrient -reducing
management measure or strategy implemented under the authority of the City and approved by
DWQ to offset nutrient and/or flow increases throughout the jurisdiction. Examples of nutrient
reducing measures may include but are not limited to conventional stormwater facilities,
constructed wetlands, or land conservation.
b. Land Conservation Offsets are an available option provided the following criteria are met:
1) The conserved land must achieve the net nutrient reductions not achieved by the new
development that conservation is credited with offsetting.
2) Proposals must quantify the reductions including identification of any actions to be taken
to achieve nutrient reductions. Examples include:
89

(a) Removal of existing impervious area
(b) Reforestation of managed open space such as agricultural land, cleared or
vacant lots. -�
(c) Restoration of the buffering functions of land adjacent to existing or new
development, e.g. converting pipe or ditch flow to dispersed sheet flow through
forested land.
3) The conserved land should be no further from the estuary than the new development
and within the same jurisdiction except where there is an interlocal agreement that
provides for development and offsetting conservation in different jurisdictions. The
agreement shall provide assurance of enforceability between jurisdictions, as well as
cross-jurisdictionai tracking and monitoring procedures.
4) There must be adequate protection to ensure that the conserved lands will not be
credited to other new developments.
5) Lands whose nutrient removal functions are established and protected through other
regulatory programs, such as wetlands and riparian buffers, would not be eligible for
conservation credit.
6) Conserved land may be used to offset flow attenuation requirements if adequate
measures are provided to ensure diffuse flow and no hydrologic degradation of the
conserved features or surface waters. --
7) Conserved land must be secured in a recorded permanent conservation easement or
equivalent legal mechanism with provisions to prohibit both farming and unapproved
logging practices. .�
C. Stormwater Management Facilities must provide the following information to gain DWQ
approval as a regional or jurisdiction -wide system:
1) Land uses in the contributing area.
2) Type of facility.
3) Expected nitrogen and phosphorus removal efficiency and peak shaving capacity.
4) Worst -case percent impervious of the contributing area at build out
5) Assumptions for on -lot treatment and attenuation
6) Calculations of nitrogen and phosphorus reduction needed, demonstration that facility
meets needs.
7) Process for tracking expenditure of treatment and attenuation capacity. --
8) Easement, restricting land use to protect Stormwater management facility and containing
adequate access for maintenance where such an instrument would be appropriate.
9) An agreement that demonstrates that (a) the developer, (b) a local government, or (c) a
private for -profit or non-profit company will operate and maintain the facilities.
10) Maintenance guarantees in conformance with the provisions of section 804. If facility is
not owned or operated by the City.
Vested Rights
Projects such as landfills, NPDES wastewater discharges, and road construction that have obtained valid state
permits prior to August 13, 2004 and projects that can demonstrate that they have vested rights in accordance with
chapter 12 of this LDC as of August 13, 2004 will not be required to comply the requirements of this section for the
for the time periods specified by this LDC except that all vested right granted by this provision shall expire five
years from the date that local or state approval of the project was granted.
a

Section 803. Water Supply Watershed Protection Regulations.
This section is adopted pursuant to the authority contained in Article 19 of Chapter 160A, Planning and Development, and
G.S. Chapter 143, Section 214.5, Water Supply Watershed Protection. The provisions of this section shall apply within the
areas designated as a public water supply watershed by the North Carolina Environmental Management Commission and
shall be defined and established on the map entitled, "Watershed Protection Map of Rocky Mount, North Carolina" ("the
^ watershed map"), which is adopted simultaneously herewith. The watershed map and all explanatory matter contained
thereon accompanies and is hereby made a part of this LDC. The provisions of this section shall amend any and all LDC,
resolutions or regulations of the City which are in conflict with or may be construed to impair or reduce the effectiveness of
�-. the City's watershed regulations.
A Watersheds General.
1. The provisions of this LDC relating to watershed protection are adopted pursuant to the authority
contained in G.S. Article 19 of Chapter 160A, Planning and Development, and G.S. Chapter 143, Section
214.5, Water Supply Watershed Protection. The provisions of this section shall apply within the areas
designated as a public water supply watershed by the North Carolina Environmental Management
Commission and shall be defined and established on the map entitled, "Watershed Protection Map of
Rocky Mount, North Carolina" ("the watershed map"), which is adopted simultaneously herewith. The
watershed map and all explanatory matter contained thereon accompanies and is hereby made a part of
this LDC. In addition, so long as the only watershed areas in the City"s jurisdiction are WS-IV-CA and WS-
IV-PA, only activities that require a sedimentation and erosion control plan for the proposed development
pursuant to the' Sedimentation and Erosion Control section of the LDC or State erosion/sedimentation law
are required to meet the provisions of this section.
2. Existing development, as defined in this LDC, is not subject to the requirements of this section.
Expansions to structures classified as existing development must meet the requirements of this section,
however, the built -upon area of the existing development is not required to be included in the density
•• calculations.
3. A pre-existing lot owned by an individual prior to the effective date of this section, regardless of whether or
not a vested right has been established, may be developed by such individual owner or any subsequent
owner for single-family residential purposes without being subject to the restrictions of this Section.
B Standards and Required Improvements,
1. All lots shall provide adequate building space in accordance with the development standards contained in
this LDC. Lots which are smaller than the minimum required for residential lots shall be identified on the
plat as, "not for residential purposes."
2. For the purpose of calculating built -upon area, total project area shall include total acreage in the tract on
which the project is to be developed.
3. Where possible, roads should be located outside of critical areas and watershed buffer areas. Roads
constructed within these areas shall be designed and constructed so to minimize their impact on water
quality.
C Exceptions.
1. Existing development, as defined in this section, is not subject to the requirements of this section.
2. A pre-existing lot owned by an individual prior to the effective date of this section, regardless of whether or
not a vested right has been established, may be developed by such individual owner or any subsequent
Owner for single-family residential purposes without being subject to the restrictions of this section.
D Establishment of Watershed Areas.
1. For the purposes of this section the City and its extraterritorial jurisdiction is hereby divided into the
following areas as delineated on the watershed map:
a. WS-IV-CA (critical area)
b. WS-IV-PA (protected area)
E Watershed Areas Described.
1. WS-IV Watershed Areas —Critical Area (WS-IV-CA). Only new development activities that require a
sedimentation and erosion control plan under the City"s sedimentation and erosion control LDC or state
erosion/sedimentation law are required to meet the provisions of this section In order to address a medium
91

to high land use intensity pattern, single-family residential uses are allowed at a maximum of two (2)
dwelling units per acre. All other residential and nonresidential development shall be allowed twenty-four
(24) percent built -upon area. New sludge application sites and landfills are specifically prohibited.
a. Permitted Uses.
1) Agriculture subject to the provisions of the Food Security Act of 1985 and the Food,
Agriculture, Conservation and Trade Act of 1990. Agricultural activities conducted after
January 1, 1993 shall maintain a minimum ten -foot vegetative buffer, or equivalent
control as determined by the soil and water conservation Commission, along all
perennial waters indicated on the most recent versions of U.S.G.S 1:24,000 (7.5
minutes) scale topographic maps or as determined by the Director of Engineering,
Animal operations greater than one hundred (100) animal units shall employ best
management practices by July 1, 1994 as recommended by the soil and water
conservation Commission.
2) Silviculture, subject to the provisions of the Forest Practices Guidelines Related to
Water Quality (15 NCAC 11.6101.0209).
3) Residential development.
4) Nonresidential development, excluding:
(a) The storage of toxic and hazardous material unless a spill containment plan is
implemented;
(b) Landfills; and
(c) Sites for land application of sludge/residuals or petroleum contaminated soils.
b. Low Density and Built -upon Limits.
1) Single-family residential development shall not exceed two (2) dwelling units per acre on
a project -by -project basis.
2) All other residential and nonresidential development shall not exceed twenty-four (24)
percent built -upon area on a project -by -project basis. For the purpose of calculating the
built -upon area, total project area shall include total acreage in the tract on which the
project is to be developed.
C. High Density and built -upon Limits.
High density and built -upon limits are permitted in this watershed area pursuant to the provisions
of Chapter 8 of this LDC.
WS-IV Watershed Areas —Protected Area (WS-IV-PA). Only new development activities that require a --
sedimentation and erosion control plan under the C4's sedimentation and erosion control LDC or State
erosion/sedimentation law are required to meet the provisions of this LDC. In order to address a medium
to high land use intensity pattern, residential and nonresidential uses are permitted in this watershed area,
subject to the requirements of this LDC, including the following:
a. Uses Permitted.
1) Agriculture, subject to the provisions of the Food Security Act of 1985 and the Food,
Agriculture, Conservation and Trade Act of 1990.
2) Silviculture, subject to the provisions of the Forest Practices Guidelines Related to
Water Quality (15 NCAC 11.6101-.0209).
3) Residential development.
4) Nonresidential development, excluding the storage of toxic and hazardous material
unless a spill containment plan is implemented.
b. Low Density and Built -upon Limits. ^
1) Single-family residential development shall not exceed two (2) dwelling units per acre or
twenty-four (24) percent built -upon area, on a project -by -project basis. For projects
without a curb and gutter street system, development shall not exceed three (3) dwelling --
units per acre or thirty-six (36) percent built -upon area, on a project -by -project basis.
2) All other residential and nonresidential development shall not exceed twenty-four (24)
percent built -upon area, on a project -by -project basis. For projects without a curb and
92

gutter street system, development shall not exceed thirty-six (36) percent built -upon
area, on a project -by -project basis.
3) For the purpose of calculating built -upon area, total project area shall include total
acreage in the tract on which the project is to be developed.
C. High Density and Built -upon Limits.
High density and built -upon limits are permitted in this watershed area pursuant to the provisions
of Chapter 8 of this LDC.
F Clustering Development in Watershed Areas.
Clustering of development is allowed in all watershed areas under the following conditions:
1. Minimum lot sizes are not applicable to single-family cluster development projects; however, the total
number of lots shall not exceed the number of lots allowed for single-family detached developments in
Chapter 8 of this LDC. Built -upon area or stormwater control requirements of the project shall not exceed
that allowed for the critical area or protected area, whichever applies.
2. All built -upon areas shall be designed and located to minimize stormwater run-off impact to the receiving
waters and minimize concentrated stormwater flow.
3. The remainder of the tract shall remain in a vegetated or natural state. Where the development has an
incorporated property owners association, the title of the open space area shall be conveyed to the
association for management. Where a property association is not incorporated, a maintenance agreement
.. shall be filed in the appropriate county.
G Buffer Areas Required.
1. A minimum one hundred (100) foot vegetative buffer is required for all new development activities that
exceed the low density option; otherwise, a minimum thirty (30) foot vegetative buffer for development
activities is required along all perennial waters indicated on the most recent versions of U.S.G.S 1:24,000
(7.5 minute) scale topographic maps or as determined by the Director of Engineering. Desirable artificial
stream bank or shoreline stabilization is permitted.
2. No new development is allowed in the buffer except for water development structures and public projects
such as road crossings and greenways where no practical alternative exists. These activities should
minimize built -upon surface area, direct runoff away from the surface waters and maximize the utilization
of stormwater best management practices.
H Rules Interpretation of Watershed Boundaries.
Where it is believed that the majority of an existing or proposed lot in its natural, undisturbed, predevelopment State
actually drains outside of the watershed (as indicated on the official watershed map), a topographic survey
prepared by a registered land surveyor may be submitted to the director of the department of planning and
development as evidence that the lot should be excluded from the official watershed area boundaries. Where
uncertainty exists as to the boundaries of the watershed area, as shown on the watershed map, the following rules
shall apply:
1. Where area boundaries are indicated as approximately following either street, alley, railroad or highway
lines or centerlines thereof, such lines shall be construed to be said boundaries.
2. Where area boundaries are indicated as approximately following lot lines, such lot lines shall be construed
to be said boundaries. However, a surveyed plat prepared by a registered land surveyor may be submitted
to the Director as evidence that one (1) or more properties along these boundaries do not lie within the
watershed area.
3. Where the watershed area boundaries lie at a scaled distance more than twenty-five (25) feet from any
parallel lot line, the location of watershed area boundaries shall be determined by use of the scale
appearing on the watershed map.
4. Where the watershed area boundaries lie at a scaled distance of twenty-five (25) feet or less form any
parallel lot line, the location of watershed area boundaries shall be construed to be the lot line.
5. Where other uncertainty exists, the Inspection Services Administrator shall interpret the watershed map as
to location of such boundaries. This decision may be appealed to the Board of Adjustment.
93

Existing Development.
Any existing development as defined in this section, may be continued and maintained subject to the conditions
provided herein. Expansions to structures classified as existing development must meet the requirements of this
section, however, the built -upon area of the existing development is not required to be included in the density
calculations.
J Compliance Prior to Issuance of Permits.
1. Except where a single-family residence is constructed on a lot of record prior to the effective date of this
section, no building or built -upon area shall be erected, moved, enlarged or structurally altered, nor shall
any building permit be issued nor shall any change in the use of any building or land be made until the
provisions of this section have been complied with.
2. No building or structure which has been erected, moved or structurally altered may be occupied nor shall a
certificate of occupancy/compliance be issued until the provisions of this section have been complied with.
K High Density Development.
1. The Planning Board may approve high density development proposed consistent with the following
standards:
a. WS-IV watershed areas —critical area (WS-IV-CA). Where new development exceeds either two --
(2) dwelling units per acre or twenty-four (24) percent built -upon area, engineered stormwater
controls shall be used to control runoff from the first inch of rainfall and development shall not
exceed fifty (50) percent built -upon area. --
b. WS-IV watershed areas —protected areas (WS-IV-PA). Where new development requires a
sedimentation and erosion control plan and exceeds either two (2) dwelling units per acre or
twenty-four (24) percent built -upon area, or three (3) dwelling units per acre or thirty-six (36)
percent built -upon area for projects without curb and gutter street system, engineered stomnwater
controls shall be used to control runoff from the first inch of rainfall and development shall not
exceed seventy (70) percent built -upon area.
C. The engineered stormwater management and/or BMP facilities shall be designed and
constructed in accordance with the criteria listed in section 804 of this LDC.
2. High density development shall meet the requirements of this LDC and the provisions of the LDC relating
to watershed protection.
Section 804 Design, Construction and Maintenance of Stormwater Management and/or
BMP Facilities.
A Stormwater Management Facility Design.
1. All stormwater management and/or best management practices (BMP) facilities shall be designed by a
North Carolina registered professional with qualifications appropriate for the type of system required; these
registered professionals are defined as professional engineers, landscape architects, to the extent that
G.S. 89A allows, and land surveyors, to the extent that the design represents incidental drainage within a
subdivision, as provided in G.S. 89C-3(7).
2. The standards used for the design and construction of all stormwater management and/or BMP facilities
shall be in accordance with the "City of Rocky Mount Standard Specifications and Design Manual," latest
edition and "The North Carolina Department of Environment and Natural Resources, Division of Water
Quality, Water Quality Section, Stormwater Best Management Practices Manual," 1999. These standards
and all amendments thereto and are hereby adopted by reference.
3. Stormwater management facilities for nutrient reduction and water quality, may consist of one (1)
treatment option or a combination of treatment options so long as the following conditions are met:
a. Eighty-five (85) percent average annual removal of total suspended solids, and;
b. Facility shall be designed in accordance with the provisions of 804 A1-2 and to meet the nutrient
reduction requirements of section 802, and
C. The discharge rate shall meet the following criteria:
L�l

The discharge rate for constructed wetlands, wet detention basins bioretention areas
and other extended detention facilities following the one -inch design storm shall be such
that the runoff draws down to the pre -storm design stage within five (5) days, but not
less than two (2) days; and
2) The post development peak discharge rate shall equal the predevelopment rate for the
--
one-year, twenty -four-hour storm.
4.
In addition to any required vegetative filters all land areas outside of the stormwater management facility
shall be provided with a ground cover sufficient to restrain erosion within thirty (30) days after any land
disturbance. Upon completion of the stormwater control structure, a permanent ground cover shall be
established and maintained as part of a maintenance agreement.
5.
A legal description of the area containing the stormwater control structure shall be prepared and included
t.
in a separate deed to the owning entity to be filed with the Register of Deeds in the appropriate county
along with any easements necessary for general access to the stormwater management structure. The
deeded area shall include the stormwater management structure, vegetative filters, all pipes and water
control structures, berms, dikes, etc., and sufficient area to perform inspections, maintenance, repairs and
reconstruction.
6.
Qualifying areas of the stormwater management structure may be considered pervious when computing
total built -upon area. However, if the structure is used to compute the percentage built -upon area for one
..
(1) site, it shall not be used to compute the built -upon area for any other site or area.
B Posting
of Financial Security Required.
1.
Plan approval for new stormwater control structures shall be conditioned on the posting of a financial
_
assurance as provided in section 1310 of this LDC for 110% of the estimated construction cost for the
purpose of construction, repair, or reconstruction necessary for adequate performance of the stormwater
management and/or BMP facility.
2.
Default under the financial assurance. Upon default of the applicant to complete and/or maintain the
stormwater control structure as spelled out in the performance bond or other security, the Director of
Engineering may obtain and use all or any portion of the funds necessary to complete the improvements
based on an engineering estimate. The Director of Engineering shall return any funds not spent in
completing the improvements to the owning entity; provided, however, no funds shall be returned to the
owning entity until the Director of Engineering is satisfied that adequate provisions have been made for the
future maintenance, repair, and if necessary, reconstruction of the stormwater controls.
3.
Default under cash security. Upon default of the owning entity to maintain, repair and, if necessary,
reconstruct the stormwater control structure in accordance with the operation and maintenance
agreement, the Director of Engineering shall obtain and use all or any portion of the cash security to make
�-
necessary improvements based on an engineering estimate. Such expenditure of funds shall only be
made after exhausting all other reasonable remedies seeking the owning entity to comply with the terms
and conditions of the operation and maintenance agreement. The Director of Engineering shall not return
...
any of the deposited cash funds.
C Maintenance and Upkeep.
1.
All stormwater management facilities and/or best management practice (BMPs) facilities that are
constructed or implemented to meet the requirements of this LDC must be maintained in a manner that
maintains the nutrient reduction levels and flow attenuation levels anticipated in the design of the facility.
2.
Prior to final plat approval or issuance of a certificate of compliance, the applicant shall enter into a binding
operation and maintenance agreement between the City and all interests in the development. Such
^"
agreement shall
a. Require the owning entity to maintain, repair and, if necessary, reconstruct the stormwater control
structure in accordance with the operation and management plan provided by the developer.
b. The operation and maintenance agreement shall be in recordable form and shall be filed with the
Register of Deeds in the appropriate county.
C. The owning entity or entities will be responsible for submitting an annual inspection report of the
--
stormwater management and/or BMP facility performed by a knowledgeable professional in the
95

field to the Director of Engineering. The annual report shall include an assessment of the
condition of the facility including any improvements needed to insure that the facility operates
safely and achieves the necessary nutrient reduction and flow attenuation levels anticipated in
the design of the facility.
d. The Stormwater Management Agreement shall clearly delineate the penalties for failure to
complete the required inspections, maintenance or improvements and shall grant the City
authority to enter the property for the purposes of ensuring compliance with the provisions of the
agreement and this LDC. If the owner and/or operator fails to complete the required inspections
or any required improvements, the City shall inspect the facilities and make any necessary
corrections. Any costs associated with this work, including administrative costs and fines, will be ^'
charged to the owner and/or party legally responsible for maintenance of the facility.
e. Maintenance agreements shall run with the land and be binding upon subsequent owners of both
the development project and/or any offsite facilities.
3. As part of the operation and maintenance agreement, an operation and maintenance plan shall be
provided by the developer for each stormwater control structure indicating what operation and
maintenance actions are needed, what specific quantitative criteria will be used for determining when --
those actions are to be taken and, consistent with the operation and maintenance agreement, who is
responsible for those actions. The plan shall clearly indicate the steps that will be taken for restoring a
stormwater control structure to design specifications if a failure occurs.
4. Landscaping and grounds management shall be the responsibility of the owning entity. however,
vegetation shall not be established or allowed to mature to the extent that the integrity of the control
structure is diminished or threatened, or to the extent of interfering with an easement or access to the
stormwater control structure.
5. Except for general landscaping and grounds management, the owning entity shall notify the Director of
Engineering prior to any repair or reconstruction of the stormwater control structure. All improvements
shall be made consistent with the approved plans and specifications of the stormwater control structure
and the operation and maintenance plan. After notification by the owning entity, the Director of
Engineering or designee shall inspect the completed improvements and shall inform the owning entity of
any required additions, changes, or modifications and of the time period to complete such improvements.
The Director of Engineering may consult with an engineer or landscape architect (to the extent that G.S.
Chapter 89A allow) designated by the Planning Board.
6. Amendments to the plans and specifications of the stormwater management and/or BMP facility, the
operation and maintenance agreement or the operation and maintenance plan shall be approved by the
Planning Board. Proposed changes shall be prepared by a North Carolina registered professional
engineer or landscape architect (to the extent that the G.S. ch. 89A allow) and submitted to and review by
the department of planning and development prior to consideration by the Planning Board.
a. If the Planning Board approves the proposed change, the owning entity of the stormwater control
structure shall file sealed copies of the revisions with the department of planning and
development.
b. If the Planning Board disapproves the changes, the proposal may be revised and resubmitted to
the Board as a new proposal. if the proposal has not been revised and is essentially the same as
that already reviewed, it shall be retumed to the owning entity.
7. If the Planning Board finds that the operation and maintenance plan is inadequate for any reason, the
Board shall notify the owning entity of any required changes and the owning entity shall prepare and file
copies of a revised operation and maintenance agreement with the department of planning and
development and such revised plan shall be the plan for the development.
D Release of the Performance Bond.
1. The Director of Engineering shall inspect the stormwater management and/or BMP facility after the
developer notifies him that all work has been completed. At or prior to this inspection, the developer shall
provide to the City:
a. Certified as -built drawings of the stormwater management and/or BMP facility.
96

r�
b. Final plat(s) creating a separate lot of record for the stormwater management facility ready for
filing with the Register of Deeds;
c. Signed deed(s) and related easements, as required, to convey the stormwater controls to the
owning entity, and
d. A certification sealed by an engineer or landscape architect (to the extent that the G.S. Chapter
89A allow) stating that the stormwater management and/or BMP facility is complete and
consistent with the approved plans and specifications.
2. If the Director of Engineering approves the inspection report and accepts the items listed in 804 D1, the
Director may release up to seventy-five (75) percent of the value of the performance bond or other
security, and authorize the issuance of a certificate of compliance for the stormwater management andlor
BMP facility. If deficiencies are found, the Director of Engineering shall direct that improvements and
inspections be made and/or documents corrected.
3. No sooner than one (1) year after year after the filing date of the deed, easements, and maintenance
agreement issuance of the certificate of compliance, the developer may request that the Director of
Engineering release the remaining value of the performance bond or other security. Upon receipt of such
request the Director of Engineering shall inspect the stormwater control structure to determine whether the
controls are performing as designed and intended.
a. If the Director of Engineering approves the report and accepts the request, the Director of
Engineering shall release the remaining performance bond or other security.
b. If the Director of Engineering does not accept the report and rejects the request, he shall provide
the developer with instructions to correct any deficiencies and all steps necessary for the release
.. of the performance bond or other security.
4. In the event the Director of Engineering discovers the need for corrective action or improvements, he shall
notify the owning entity of the needed improvements and the date by which the corrective action is to be
^„ completed. All improvements shall be made consistent with the plans and specifications of the stormwater
control structure and the operation and maintenance plan . After notification by the owning entity, the
Director of Engineering shall inspect and approve the completed improvements.
^
Section 805 Permits and Enforcement
A Permits
Permits for all development activities covered by this chapter shall be issued in accordance with section 717 of this
LDC.
B Enforcement
Except as otherwise provided in this chapter, enforcement of the provisions of this chapter shall be in accordance
with chapter 12 of this LDC.
C Appeals
Except as otherwise noted in this chapter, appeals of any order, requirement, decision or determination made by
the Director of Engineering may be made to and decided by the Board of Adjustment as provided in Chapter 3 of
this LDC.
97

Appendix M. City of Rocky Mount Standard
Stormwater Facility Operation and
Maintenance Agreement
98

NORTH CAROLINA STORM WATER FACILITY OPERATION
NASH COUNTY AND MAINTENANCE AGREEMENT
THIS AGREEMENT, made and entered into this 29 day of December, 2003, by and between
, and the City of Rocky Mount, a North Carolina municipal corporation
located in Nash and Edgecombe Counties (the "City');
WI TNESSETH:
WHEREAS, the City has adopted certain storm water management regulations applicable to the
property of Permittee located in the City of Rocky Mount, Nash County, North Carolina, and more particularly
-� described In Book , Page County Registry (the "Property); and
WHEREAS, such regulations require the Permittee to operate and maintain an engineered storm water
control facility as part of the development of the Property; and
WHEREAS, Permittee has constructed a private on -site engineered storm water control facility (the
"Facility") to satisfy the requirements of such regulations, the boundaries of such Facility being describe in
Appendix 1 attached hereto and incorporated herein by reference; and
WHEREAS, a separate deed vesting title to the real estate on which the Facility is located in Permittee
has been recorded in the Nash County Registry; and
WHEREAS, as a condition of the development of the Property, Permittee is required to enter into an
operation and maintenance agreement providing for the continued operation and maintenance of the Facility.
NOW, THEREFORE, for and in consideration of the premises and the approval by the City of the
w development activities on the Property, the Permittee does hereby covenant and agree with the City that the
Facility shall be held, operated, maintained, and encumbered pursuant to the covenants and conditions
hereinafter set forth;
1. No conveyance of Facility without New Agreement. Permittee covenants and agrees that it will not
convey, transfer, assign, lease, or otherwise release or relinquish ownership or control of the Facility, in
whole or in part, unless and until the proposed new owner of the Facility, or any interest therein, has
.w entered into a Storm Water Facility Operation and Maintenance Agreement with the City containing
substantially the same terms and conditions as this Agreement, and a copy thereof has been recorded
in the County Register of Deed's Office.
•- 2. Operation and Maintenance Plan. Permittee has prepared and submitted to the City an Operation and
Maintenance Plan for the Facility which has been approved by the City. Permittee shall operate,
maintain, repair, and, if necessary, reconstruct the Facility in accordance with the Operation and
Maintenance Plan.
3. Inspection and Maintenance. of Facility. In addition to the maintenance provided for in the Operation
and Maintenance Plan, Permittee shall undertake and provide the following inspection, repair, and
maintenance of the Facility:
a. Grassing around the Facility shall be maintained to prevent the erosion of these areas. The areas
shall be periodically mowed to maintain the aesthetic quality of the site and to prevent a reduction in
capacity of the stormwater system. Grass should to exceed a height of 15 inches. All eroded areas
shall be repaired.
b. Open ditches shall be kept free of undesirable growth and mowed or maintained to the design
cross-section and area as shown on the construction plans approved by the City Engineer and on
file in the office of the City Engineer. Growth on the slopes and bottom should not exceed a height
of 8 inches.
c. Landscaping of the area around the Facility shall not reduce the capacity or hinder operation and
maintenance of the Facility. Landscaping shall be maintained to ensure that landscape materials
live and prosper. Re -vegetation of areas may be required by the City Engineer.
d. The Facility shall be routinely checked as directed by the City Engineer for, and cleared of, all
accumulation of debris and the Facility's outlet structure cleared of any blockage that is present.
99

e. Storm drainage pipes and culverts shall be periodically inspected on a schedule established by the
City Engineer for debris and sand build-up. T hey shall be cleaned as necessary to provide for the
free conveyance of stormwater as designed.
f. The Facility shall be maintained at the design depth as shown on the construction plans approved
by the City Engineer and on file in the office of the City Engineer. The pond shall be inspected and
maintained by the Permittee on a regular basis. Debris and sedimentation shall be removed by the
Permittee when:
1. The primary outlet capacity is impaired and/or;
2. The depth of the Facility has been reduced by more than one foot from the original depth or the
Facility volume is reduced by 20% of the design impoundment volume. Sediment bays and
forebays shall be kept clean of any sediment.
g. The Facility shall be maintained in a manner to control insects, odors and algae as determined
necessary by the City Engineer.
h. Any fencing or other security measures shall be maintained in good condition. If no fencing or
security measures are included with the original construction, they shall be added at the Permittee's
expense at such time as the City Engineer determines that unauthorized persons are disturbing the
Facility and that security measures will help prevent such unauthorized activity.
4. Right of Inspection by Cam. The Permittee hereby grants the City the right, privilege and easement over and ---
cross the Property lying between any public street or right of way and the Facility for the purpose of
inspecting, correcting, repairing, replacing or maintaining the Facility as provided in this Agreement. This
right, privilege and easement is appurtenant to and shall run with the Property.
5. Remedies for Violations of this Agreement.
a. if the Permittee shall fail to maintain or repair the Facility as set forth herein, or otherwise violates this
Agreement, the city may order the Permittee to undertake the necessary repair or maintenance or to --
correct such violation. If the Permittee shall fail to comply with such order within thirty (30) days from
the date thereof, the permitee shall be considered in violation of this agreement and Chapter 8 of the
LDC and will be subject to penalties as provided in section 1205 of the LDC and pursuant to the �.
authority contained in Article 19 of Chapter 160A, Planning and Development and 15A NCAC 213.0258.
Should the permitee fail to make the required corrections within 30 days of the issuance of the civil
penalty, the City may enter the Property and perform all necessary work to place the Facility in proper
working condition. The full cost of performing the work including administrative costs and penalties shall be assessed as a lien on the property.
b. The City shall have the right to bring an action and recover sums due, damages, seek injunctive relief,
and/or such other and further relief as may be just and appropriate.
c. The remedies provided by this paragraph are cumulative; and are in addition to any other remedies
provided by law.
6. No Waiver of Breach. In the event of a breach of any term of this Agreement, any delay or failure on the --
part of the City to exercise any rights, powers, or remedies herein provided shall not be construed as a
waiver thereof or acquiescence of such breach or any future breach.
7. Amendments. This Agreement may be amended, revised or modified only by a written document signed by
the parties.
8. Bindinq Effect. The conditions and restrictions set forth herein with regard to the Facility shall run with the
land and shall bind the Permittee and its successors and assigns and all parties claiming by, through, or
under them shall be taken to hold, agree, and covenant with the City, with its successors and assigns, and with each of them to conform to and observe said conditions and restrictions. The City shall be deemed a
beneficiary of the conditions and restrictions set forth herein and such conditions and restrictions shall run
with the land in favor of the City.
9. Warranties of Title. The Permittee covenants and warrants that it is lawfully seized and possess of the
Facility and real estate described in Appendix 1, that it has good right and lawful authority to enter into this
Agreement for the purposes herein expressed, and that no consent or waiver by the holder of any mortgage,
100

deed of trust, or other security instrument, or any other person, firm, or corporation is required prior to
entering into this Agreement.
10. Interpretation. Use of the masculine gender herein includes the feminine and neuter, and the singular
number used herein shall equally include the plural. The captions preceding the various provisions of this
Agreement are for the convenience of reference only, and shall not be used as an aid in interpretation or
construction of this Agreement.
11. Severability. Invalidation of any one of these covenants or conditions by judgement or order of any court
shall in no way affect any of the other provisions, which shall remain in full force and effect.
IN WITNESS WHEREOF, the parties have hereunto set their hands and seals this the day and year first
above written.
Owner
Name of Owner
Address
City of Rocky Mount
ATTEST:
CITY CLERK
STATE OF NORTH CAROLINA
COUNTY OF
a notary public in and for said county and state, certify that
personally appeared before me this date, stated that he or she is
of , and acknowledged
the execution of the foregoing instrument with the City of Rocky Mount on behalf of said
This the
My Commission Expires:
day of 20_.
Notary Public
101

STATE OF NORTH CAROLINA
COUNTY OF
I, , a notary public in and for said county and state, certify
that Jean M. Bailey personally appeared before me this day, stated that he or she is the City Clerk of the
City of Rocky Mount, a municipal corporation, and that by authority duly given and as the act of the City,
foregoing contract was signed in its corporate name by its
sealed with its corporate seal, and attested by herself as its said City Clerk.
This the day of , 20
My Commission Expires:
(SEAL)
APPROVED AS TO FORM:
City Attorney
Notary Public
102

P�
Appendix N. City of Rocky Mount Standard
Conservation Easement
103

Tax Parcel ID #
NORTH CAROLINA
COUNTY
CONSERVATION EASEMENT
Tar River Watershed - Rocky Mount, North Carolina
THIS CONSERVATION EASEMENT (this "Conservation Easement") made and entered
into this day of , by and between
with an address at (whether one or more,
"Grantor"), and the CITY OF ROCKY MOUNT, a North Carolina municipal corporation with an
address of Post Office Drawer 1180, Rocky Mount, North Carolina 27802 ("Grantee").
RECITALS AND CONSERVATION PURPOSES
A. Grantor is the sole owner in fee simple of certain real estate containing approximately
acres located in County, North Carolina, more particularly described in Exhibit A,
attached hereto and by this reference incorporated herein (the "Property"); and _
B. The Property is located in the Tar/Pamlico River Basin, which has been designated nutrient
sensitive by the North Carolina Division of Water Quality and the North Carolina Environmental
Management Commission; and
D. The Property possess natural and scenic values which Grantor intends to conserve and
maintain by the continuation of land use patterns existing at the time of this grant; and
E. Grantor as owner of the Property intends to convey to Grantee the right to preserve and
protect the conservation values of the Property in perpetuity; and
F. Grantee agrees by accepting this grant to honor the intentions of Grantor stated herein
and to preserve and protect in perpetuity the conservation values of the Property for the benefit of the
current generation and the generations to come;
NOW, THEREFORE Grantor, for valuable consideration paid by Grantee, the receipt of which is
hereby acknowledged, has and by these presents, does hereby unconditionally and irrevocably grant,
bargain, sell, and convey to Grantee a perpetual Conservation Easement of the nature, character, and extent
hereinafter set forth in, over, under, through and across the Property, as described in Exhibit A attached
hereto, together with the right of ingress to and egress from the Property over the adjoining property of
Grantor, including the right with regard to said Conservation Easement to preserve and protect the —
conservation values thereof as described herein.
104

ARTICLE I - PURPOSE
It is the purpose of this Conservation Easement to assure that the Property will be retained
forever in its natural state and to prevent any use of the Property which will impair or interfere with the
conservation of the Property.
ARTICLE II - DURATION OF EASEMENT
This Conservation Easement shall be perpetual. It is an easement in gross, runs with the land,
and is enforceable by Grantee against Grantor, his, her, its, or their representatives, successors, assigns,
lessees, agents, and licensees.
ARTICLE III - PROHIBITED AND RESTRICTED ACTIVITIES
Any activity on, or use of, the Property inconsistent with the purpose of this Conservation
Easement is prohibited. The Property shall be maintained in its natural, scenic, wooded and open
condition and restricted from any development or other use that would impair or interfere with the
conservation purpose of this Conservation Easement set forth above.
All rights reserved by Grantor are reserved for Grantor, Grantor's representatives, successors,
and assigns and are considered to be consistent with the conservation purpose of this Conservation
Easement, and, unless specifically stated otherwise herein, require no prior notification to or approval
by Grantee.
Notwithstanding the foregoing, Grantor and Grantee shall have no right to agree to any activity
that would result in the termination of this Conservation Easement.
Without limiting the generality of the foregoing, the following activities and uses by Grantor,
Grantee, or any other person are expressly prohibited or restricted:
A. Industrial and Commercial Use. Industrial and commercial activities of any type or
kind and any right of access or passage for such purposes are prohibited.
B. Agricultural, Timber Harvesting, Grazing and Horticultural Use. Agricultural,
farming, timber harvesting, grazing, horticultural and animal husbandry operations are prohibited;
provided, however, those trees which are damaged or fallen as a result of disease, blight, or some
weather related event such as a hurricane or other severe storm may be removed, including stumps.
C. Disturbance of Natural Features, Plants and Animals. There shall be no cutting or
removal of trees, or the disturbance of other natural features.
D. Construction_ of Buildings and Use. There shall be no constructing or placing of any
residence, building, mobile home, asphalt or concrete pavement, antenna or any other temporary or
permanent structure or facility on, above, or under the Property.
105

E. Mineral Use. Excavation, Dredging. There shall be no filling, excavation, dredging,
mining or drilling; no removal of topsoil, sand, gravel, rock, peat, minerals or other materials, and no
change in the topography of the land in any manner except as necessary for the purpose of combating
erosion or incidental to any conservation management activities otherwise permitted in this
Conservation Easement.
F. Wetlands and Water Quality. There shall be no pollution or alteration of water bodies
and no activities that would be detrimental to water purity or that would alter natural water levels,
drainage, sedimentation and/or flow in or over the Property or into any surface waters, or cause soil
degradation or erosion; in addition, there shall be no diking, dredging, alteration, draining, filling or
removal of wetlands, except for activities to restore natural hydrology or wetlands enhancement as
permitted by state and any other appropriate authorities.
G. Dumping. Dumping of soil, trash, ashes, garbage, waste, abandoned vehicles,
appliances, or machinery, or other materials on the property is prohibited. ^'
H. Conveyance and Subdivision. The Property shall not be subdivided, partitioned, or
conveyed except in its current configuration as an entity.
L Other Activities or Use. Any use or activity not expressly permitted in ARTICLE IV —
PERMITTED ACTIVITIES of this Conservation Easement is prohibited.
ARTICLE IV — PERMITTED ACTIVITIES
The following activities or uses on the Property are not inconsistent with the purpose of this
Conservation Easement and are reserved to Grantor:
A. Fencing. The Property may be fenced, provided the same can be accomplished without
cutting or removing trees, or disturbing the natural features of the land.
B. Hunting, Fishing and Recreational Activities. Hunting, fishing, and recreational _.
activities may be conducted on and from the Property provided the same are conducted in conformity
with all applicable laws, rules, and regulations governing the same, and provided further, that there
shall be no surface alteration or other development of the Property in connection therewith.
C. Existing Buildings and Structures. Existing buildings and structures, including
billboards located on the Property as of the date hereof, may remain on the Property and be repaired
and maintained, but may not be enlarged or expanded. In addition, "No Trespassing", "For Sale", For
Lease" signs, or similar informational signs no larger than eight (8) square feet may be placed on the
Property.
D. Public Utilities. Public utility easements may be granted and facilities, including,
without limitation, lines, wires, cables, pipes, meters, pumps, and Iift stations may be placed on the
Property, and, to the extent necessary, but only to the extent necessary, trees, undergrowth, and other
natural and man made obstructions may be removed to install such public utility facilities.
106

ARTICLE V - ENFORCEMENT & REMEDIES
A. Grantee's Remedies. If Grantee determines that Grantor is in violation of any of the
terms of this Conservation Easement or that a violation is threatened, Grantee shall give written notice
to Grantor of such violation and demand corrective action sufficient to cure the violation and, where
the violation involves injury to the Property resulting from any use or activity inconsistent with the
purpose of this Conservation Easement, to restore the portion of the Property so injured. If Grantor
fails to cure the violation within thirty (30) days after receipt of notice thereof from Grantee, or, if the
circumstances are such that the violation cannot reasonably be cured within a thirty (30) day period,
fails to begin curing such violation within the thirty (30) day period, or, if having commenced actions
to cure the violation, fails to continue diligently to complete the cure, Grantee may bring an action at
law or in equity in any court of competent jurisdiction to enforce the terms of this Conservation
Easement, to enjoin the violation, ex pane as necessary, by temporary or permanent injunction, to
recover any damages to which it may be entitled for violation of any term of this Conservation
Easement or for injury to any conservation values protected by this Conservation Easement, including
damages for the loss of scenic, aesthetic, or environmental values, and to require the restoration of the
Property to the condition that existed prior to any such injury. Without limiting Grantor's liability
therefore, Grantee, in its sole discretion, may apply any damages recovered to the cost of undertaking
any corrective action on the Property. If Grantee, in its sole discretion, determines that circumstances
require immediate action to prevent or mitigate significant damage to the conservation values of the
Property, Grantee may pursue its remedies under this paragraph without prior notice to Grantor or
without waiting for the period provided for cure to expire. Grantee's rights under this paragraph apply
equally in the event of either actual or threatened violations of the terms of this Conservation
Easement, and Grantor agrees that Grantee's remedies at law for any violation of the terms of this
Conservation Easement are inadequate and that Grantee shall be entitled to the injunctive relief
described in this paragraph, both prohibitive and mandatory, as well as specific performance of the
terms of this Conservation Easement, without the necessity of proving either actual damages or the
inadequacy of otherwise available legal remedies. Grantee's remedies described in this paragraph shall
be cumulative and shall be in addition to all remedies now or hereafter existing at law or in equity.
B. Right of Entry: Grantee, its employees and agents, shall have the right to enter the
Property (including the concomitant right to cross the adjoining property of Grantor) at any reasonable
time for the purpose of preparing baseline documentation with respect to the Property and for
inspecting the Property to determine whether Grantor is complying with the terms, conditions, and
restrictions of this Conservation Easement.
C. Costs of Enforcement. Any costs incurred by Grantee in enforcing the terms of this
Conservation Easement against Grantor, including, without limitation, costs of suit and attorneys' fees,
and any costs of restoration necessitated by Grantor's violation of the term of this Conservation
Easement, shall be paid by Grantor.
D. Grantee's Discretion. Enforcement of the terms of this Conservation Easement shall be
-- at the discretion of Grantee, and any forbearance by Grantee to exercise its rights hereunder shall not
be deemed or construed to be a waiver by Grantee of such term or of any subsequent breach of the
same or any other term of this Conservation Easement or of any of Grantee's rights hereunder. No
107

delay or omission by Grantee in the exercise of any right or remedy upon any breach by Grantor shall
impair such right or remedy or be construed as a waiver.
E. Waiver of Certain Defenses. Grantor hereby waives any defense of lathes, estoppel, or
prescription.
F. Acts Beyond Grantor's_ Control. Nothing contained in this Conservation Easement shall
be construed to entitle Grantee to bring any action against Grantor for any injury to or change in the
Property resulting from causes beyond Grantor's control, including, without limitation, fire, flood,
storm, and earth movement, or from any prudent action taken by Grantor under emergency conditions
to prevent, abate, or mitigate significant injury to the Property or to persons resulting from such causes.
ARTICLE VI - DOCUMENTATION AND TITLE
A. Property Condition The parties acknowledge that the Property is currently undeveloped
land, with no improvements other than the following buildings and structures:
B. Easements and Rights of Way. The Property is subject to the following easements and
rights of way:
C. Covenants of Title. Grantor covenants with Grantee that Grantor is seized of the
Property in fee simple and has the right to grant and convey this Conservation Easement; that there is
legal access to the Property; that the Property is free and clear of any and all encumbrances except as _
stated herein; and that Grantor will warrant and defend Grantee's right to use and enjoy all of the
benefits derived from and arising out of this Conservation Easement against the claims of all persons
whomsoever.
D. Subordination. At the time of conveyance of this Conservation Easement, the Property
is subject to the following mortgages and deeds of trust: _
incorporated by this
reference, the holder or holders of which have agreed by separate instrument, which will be recorded _
immediately after this Conservation Easement, to subordinate their rights in the Property to this
Conservation Easement in perpetuity and to prevent any modification or extinguishment of this
Conservation Easement by the exercise of any rights under any mortgage or deed of trust. The priority
of the any mortgage or deed of trust with respect to any valid claim on the part of the existing holder to
the proceeds of any sale, condemnation proceedings, or insurance or to the leases, rents, and profits of
the Property shall not be affected thereby, and any lien that may be created by Grantee's exercise of —.
any of its rights under this Conservation Easement shall be junior to any existing mortgage or deed of
trust. Upon request, Grantee agrees to subordinate its rights under this Conservation Easement to the
108

rights of any future mortgage holders or beneficiaries of deeds of trust to the proceeds, leases, rents,
and profits described above and likewise to subordinate its rights under any lien and to execute any
documents required with respect to such subordination, except that the priority of any lien created by
Grantee's exercise of any of its rights under this Conservation Easement prior to the creation of a
mortgage or deed of trust shall not be affected thereby, nor shall this Conservation Easement be
subordinated in any other respect.
E. No. Forfeiture: Nothing contained herein will result in a forfeiture or reversion of
Grantor's title in any respect.
ARTICLE VII. MISCELLANEOUS
A. Subsequent Transfers. Grantor shall incorporate the terms of this Conservation
Easement in any deed or other legal instrument by which Grantor transfers any interest in the
Property, including, without limitation, any liens or leasehold interest. Grantor further agrees to give
written notice to Grantee of the proposed transfer of any interest at least thirty (30) days prior to the
date of such transfer. The failure of Grantor to perform any act required by this paragraph shall not
impair the validity of this Conservation Easement or limit its enforceability in any way.
B. Conservation Purpose.
(1) The Grantee, for itself, its successors and assigns, agrees that this Conservation
Easement shall be held exclusively for conservation purposes.
(2) The parties hereto recognize and agree that the benefits of this Conservation
-- Easement are in gross and assignable, provided, however that Grantee hereby covenants and agrees,
that in the event it transfers or assigns this Conservation Easement, the transferee or assignee
receiving the interest will be a qualified organization as that term is defined in Section 170(h)(3) of the
Internal Revenue Code of 1954, as amended (the "Internal Revenue Code"), or any successor section,
and the regulations promulgated thereunder, which is organized or operated primarily for one of the
conservation purposes specified in Section 170 (h)(4)(A) of the Internal Revenue Code, and Grantee
^' further covenants and agrees that the terms of the transfer or assignment will be such that the transferee
or assignee will be required to continue to carry out in perpetuity the conservation purpose that this
Conservation Easement was originally intended to advance, set forth herein.
C. Extinguishment. If circumstances arise in the future that render the purpose of this
Conservation Easement impossible to accomplish, this Conservation Easement may only be terminated
or extinguished, whether in whole or in part, by judicial proceedings in a court of competent
jurisdiction, and the amount of the proceeds to which Grantee shall be entitled, after the satisfaction of
prior claims, from any sale, exchange, or involuntary conversion of all or any portion of the Property
subsequent to such termination or extinguishment, shall be determined, unless otherwise provided by
law, in accordance with subparagraph D below. Grantee shall use all such proceeds in a manner
consistent with the conservation purposes of this grant.
D. Proceeds. This Conservation Easement constitutes a real property interest immediately
vested in Grantee, which, for the purposes of subparagraph C above and subparagraph E below, the
109

parties stipulate to have a fair market value determined by multiplying the fair market value of the
Property unencumbered by the Conservation Easement (minus any increase in value after the date of
this grant attributable to improvements) by the ratio of the fair market value of the Conservation
Easement on the date of this grant to the fair market value of the Property, without deduction for the
value of the Conservation Easement, on the date of this grant. The values at the time of this grant shall
be those values used to calculate the deduction for federal income tax purposes allowable by reason of
this grant, pursuant to Section 170(h) of the Internal Revenue Code, or if purchased by Grantee, the
total consideration paid to Grantor for the Conservation Easement, or if part gift and part purchase, the
total amount of the deductible value and the amount of the purchase. For purposes of this paragraph,
the ratio of the value of the Conservation Easement to the value of the Property unencumbered by the
Conservation Easement shall remain constant.
E. Condemnation: Whenever all or part of the Property is taken in exercise of eminent
domain by public, corporate, or other authority so as to abrogate the restrictions imposed by this
Conservation Easement, Grantor and Grantee shall join in appropriate actions at the time of such !'
taking to recover the full value of the taking and all incidental or direct damages resulting from the
taking, which proceeds shall be divided in accordance with the proportionate value of Grantee's and
Grantor's interests as provided in subparagraph D above. All expenses including attorneys' fees
incurred by Grantor and Grantee in this action shall be paid out of the recovered proceeds to the extent
not paid by the condemning authority. —
F. Access. No right of access to the general public to any portion of the Property is
conveyed by this Conservation Easement.
G. Liberal Construction. Any general rule of construction to the contrary notwithstanding,
this Conservation Easement shall be liberally construed in favor of the grant to effect the purpose of
this Conservation Easement and the policy and purpose set forth in Section 170(h)(4)(A) of the
Internal Revenue Code.
H. Severability. If any provision of this Conservation Easement, or the application thereof
to any person or circumstance, is found to be invalid, the remainder of the provisions of this
Conservation Easement, or the application of such provision to persons or circumstances other than ^.
those as to which it is found to be invalid, as the case may be, shall not be affected thereby.
I. Entire Agreement. This instrument sets forth the entire agreement of the parties with —
respect to the Conservation Easement and supersedes all prior discussions, negotiations,
understandings or agreements relating to the Conservation Easement. If any provision is found to be
invalid, the remainder of the provisions of this Conservation Easement, and the application of such --
provision to persons or circumstances other than those as to which it is found to be invalid, shall not be
affected thereby.
J. Recording. Grantees shall record this instrument and any amendment hereto in a timely
fashion in the official records of County, North Carolina, and may re-record it at
any time as may be required to preserve its rights.
110

K. Joint Obligations. The obligations imposed by this Conservation Easement upon
Grantor shall be joint and several.
L. Successors. The covenants, terms, conditions, and restrictions of this Conservation
Easement shall be binding upon, and inure to the benefit of the parties hereto and their respective
personal representatives, heirs, successors, and assigns and shall continue as a servitude running in
perpetuity with the Property.
M. Termination of Rights and Obligations. A party's rights and obligations under this
Conservation Easement terminate upon transfer of the party's interest in the Conservation Easement or
Property, except that liability for acts or omissions occurring prior to transfer shall survive transfer.
N. Captions. The captions in this instrument have been inserted solely for convenience of
reference and are not a part of this instrument and shall have no effect upon construction or
interpretation.
O. Counterparts. The parties may execute this instrument in two or more counterparts,
which shall, in the aggregate, be signed by both parties; each counterpart shall be deemed an original
instrument as against any party who has signed it. In the event of any disparity between the
counterparts produced, the recorded counterpart shall be controlling.
P. Notices. Any notices shall be sent by registered or certified mail, return receipt
requested, addressed to the parties as set forth above, or to such other addresses such party may
establish in writing to the other. In any case where the terms of this Conservation Easement require
the consent of any party, such consent shall be requested by written notice. Such consent shall be
deemed denied unless, within thirty (30) days after receipt of notice, a written notice of approval and
the reason therefore has been mailed to the party requesting consent.
•• Q. Amendments. Grantor and Grantee are free to jointly amend this Conservation
Easement to meet changing conditions, provided that no amendment will be allowed that is
inconsistent with the purpose of this Conservation Easement, affects the perpetual duration of this
-- Conservation Easement, the status of Grantee under any applicable law, or that will affect the
qualification of this Conservation Easement under Section 170(h) of the Internal Revenue Code. Such
amendment(s) shall be effective upon recording in the public records of County, North
^� Carolina.
R. Environmental Condition of Property. Grantor warrants and represents to Grantee that
to the best of Grantor's knowledge after appropriate inquiry and investigation: (a) the Property
described herein is and at all times hereafter will continue to be in full compliance with all federal,
state, and local environmental laws and regulations, and (b) as of the date hereof there are no
hazardous materials, substances, wastes, or environmentally regulated substances (including, without
limitation, any materials containing asbestos) located on, in, or under the Property or used in
connection therewith, and that there is no environmental condition existing on the Property that may
prohibit or impede use of the Property for the purposes set forth herein.

S. Signs. Grantee shall have the right to post visible signs along the boundaries of the
Property recognizing the participation of the Fund in the acquisition and protection of the Property and
that the Property will remain in its protected state. -�
T. Costs and Liabilities. Grantor shall retain all responsibilities and shall bear all costs and
liabilities of any kind related to the ownership, operation, upkeep, and maintenance of the Property,
including, without limitation, the payment of all taxes and assessments levied on or assessed against
the Property by any competent authority and the maintenance of adequate comprehensive general
liability insurance coverage. Grantor shall keep the Property free of any liens arising out of any work ^'
performed for, materials furnished to, or obligations incurred by, Grantor or anyone claiming under
Grantor.
TO HAVE AND TO HOLD the Conservation Easement unto Grantee, its successors and
assigns, forever.
IN WITNESS WHEREOF, Grantor and Grantee have executed this Conservation Easement,
each having adopted the type written word ("SEAL") as their personal/corporate seal, as of the day and
year first written above.
GRANTOR:
NORTH CAROLINA
COUNTY
(SEAL)
a Notary Public in and for said County and State so hereby -�
certify that personally appeared before me this day and being
duly sworn, acknowledged that he/she executed the foregoing instrument for the purposes contained
within. —
WITNESS my hand and official stamp or seal, this the day of
My Commission Expires:
Notary Public
112

EXHIBIT A
CONSERVATION EASEMENT
DESCRIPTION
ROCKYMOUNT/030163-953/221616 v.l
113

Appendix 4. City of Rocky Mount Standard Low
Maintenance Conservation Easement
114

Tax Parcel ID #
NORTH CAROLINA
COUNTY
LOW MAINTENANCE CONSERVATION EASEMENT
Rocky Mount, North Carolina
THIS LOW MAINTENANCE CONSERVATION EASEMENT (this "Low Maintenance
Conservation Easement") made and entered into this day of by
and between with an address at (whether one or
more, "Grantor"), and the CITY OF ROCKY MOUNT, a North Carolina municipal corporation with
an address of Post Office Drawer 1180, Rocky Mount, North Carolina 27802 ("Grantee").
RECITALS AND CONSERVATION PURPOSES
A. Grantor is the sole owner in fee simple of certain real estate containing approximately
acres located in County, North Carolina, more particularly described in Exhibit A,
,.� attached hereto and by this reference incorporated herein (the "Property"); and
B. The Property is located in the Tar/Pamlico River Basin, which has been designated
nutrient sensitive by the North Carolina Division of Water Quality and the North Carolina
Environmental Management Conunission; and
C. The Property possess natural and scenic values which Grantor intends to conserve and
maintain by the continuation of land use patterns approved at the time of this development; and
�- D. Grantor as owner of the Property intends the property to be maintained in perpetuity,
such that it maintains its nutrient removal properties intended by the approved development plan; and
-- E. Grantor agrees to operate and maintain the Property such a manner to not increase the
amount of nitrogen and phosphorus discharged in the stormwater runoff from the site.
NOW, THEREFORE Grantor, for valuable consideration paid by Grantee, the receipt of which is
hereby acknowledged, has and by these presents, does hereby unconditionally and irrevocably grant,
bargain, sell, and convey to Grantee a perpetual Low Maintenance Conservation Easement of the nature,
character, and extent hereinafter set forth in, over, under, through and across the Property, as described in
Exhibit A attached hereto, together with the right of ingress to and egress from the Property over the
adjoining property of Grantor, including the right with regard to said easement to preserve and protect the
conservation values thereof as described herein.
115

ARTICLE I - PURPOSE
It is the purpose of this Low Maintenance Conservation Easement to assure that the Property -'
will be retained forever in an open vegetative condition as shown on the approved plans and to prevent
any use of the Property which will impair or interfere with the nutrient removal properties of the _
Property.
ARTICLE II - DURATION OF EASEMENT
This Low Maintenance Conservation Easement shall be perpetual. It is an easement in gross,
runs with the land, and is enforceable by Grantee against Grantor, his, her, its, or their representatives,
successors, assigns, lessees, agents, and licensees.
ARTICLE III - PROHIBITED AND RESTRICTED ACTIVITIES
Any activity on, or use of, the Property inconsistent with the purpose of this Low Maintenance
Conservation Easement is prohibited. The Property shall be maintained in an open vegetative
condition in the form and state shown on the approved plan and restricted from any development or --
other use that would impair or interfere with the nutrient removal purpose of this easement set forth
above. Any alterations of the property must be approved by the Grantee in writing
The Grantor shall not undertake any action including the application of fertilizer, pesticides or
herbicides that may increase the nitrogen and/or phosphorus contained in the stormwater runoff from
the Property. �-
All rights reserved by Grantor are reserved for Grantor, Grantor's representatives, successors,
and assigns and are considered to be consistent with the conservation purpose of this easement, and,
unless specifically stated otherwise herein, require no prior notification to or approval by Grantee.
Notwithstanding the foregoing, Grantor and Grantee shall have no right to agree to any activity that —
would result in the termination of this Conservation Easement.
Without limiting the generality of the foregoing, the following activities and uses by Grantor,
Grantee, or any other person are expressly prohibited or restricted:
A. Industrial and Commercial Use. Industrial and commercial activities of any type or
kind and any right of access or passage for such purposes are prohibited.
B. Agricultural, Timber Harvesting, Grazing and Horticultural Use. Agricultural,
farming, grazing, horticultural and animal husbandry operations are prohibited;
C. Construction of Buildings and Use. There shall be no constructing or placing of any
residence, building, mobile home, asphalt or concrete pavement, antenna or any other temporary or
permanent structure or facility on , above, or under the Property.
116

D. Mineral Use Excavation Dredizin. There shall be no filling, excavation, dredging,
mining or drilling; no removal of topsoil, sand, gravel, rock, peat, minerals or other materials, and no
change in the topography of the land in any manner except as necessary for the purpose of combating
erosion or incidental to any conservation management activities otherwise permitted in this
Conservation Easement.
E. Wetlands and Water Qugity. There shall be no pollution or alteration of water bodies
and no activities that would be detrimental to water purity or that would alter natural water levels,
drainage, sedimentation and/or flow in or over the Property or into any surface waters, or cause soil
degradation or erosion; in addition, there shall be no diking, dredging, alteration, draining, filling or
removal of wetlands, except for activities to restore natural hydrology or wetlands enhancement as
permitted by state and any other appropriate authorities.
F. Dumping. Dumping of soil, trash, ashes, garbage, waste, abandoned vehicles,
appliances, or machinery, or other materials on the property is prohibited.
G. Conveyance and Subdivision. The Property shall not be subdivided, partitioned, or
conveyed except in its current configuration as an entity.
w H. Other Activities or Use. Any use or activity not expressly permitted in ARTICLE IV --
PERMITTED ACTIVITIES of this Conservation Easement is prohibited.
ARTICLE IV — PERMITTED ACTIVITIES
The following activities or uses on the Property are not inconsistent with the purpose of this
Conservation Easement and are reserved to Grantor:
A. Fencing. The Property may be fenced, provided the same can be accomplished without
cutting or removing trees, or disturbing the natural features of the land.
B. Hunting, Fishing, and Recreational Activities. Hunting, fishing, and recreational
activities may be conducted on and from the Property provided the same are conducted in conformity
with all applicable laws, rules, and regulations governing the same, and provided further, that there
shall be no surface alteration or other development of the Property in connection therewith.
C. Public Utilities. Public utility easements may be granted and facilities, including,
without limitation, lines, wires, cables, pipes, meters, pumps, and lift stations may be placed on the
Property.
117

ARTICLE V - ENFORCEMENT & REMEDIES
A. Grantee's Remedies. If Grantee determines that Grantor is in violation of any of the
terms of this Conservation Easement or that a violation is threatened, Grantee shall give written notice
to Grantor of such violation and demand corrective action sufficient to cure the violation and, where
the violation involves injury to the Property resulting from any use or activity inconsistent with the
purpose of this Conservation Easement, to restore the portion of the Property so injured. If Grantor
fails to cure the violation within thirty (30) days after receipt of notice thereof from Grantee, or, if the
circumstances are such that the violation cannot reasonably be cured within a thirty (30) day period,
fails to begin curing such violation within the thirty (30) day period, or, if having commenced actions
to cure the violation, fails to continue diligently to complete the cure, Grantee may bring an action at
law or in equity in any court of competent jurisdiction to enforce the terms of this Low Maintenance "
Conservation Easement, to enjoin the violation, ex parte as necessary, by temporary or permanent
injunction, to recover any damages to which it may be entitled for violation of any term of this Low
Maintenance Conservation Easement or for injury to any conservation values protected by this
easement, including damages for the loss of scenic, aesthetic, or environmental values, and to require
the restoration of the Property to the condition that existed prior to any such injury. Without limiting
^
Grantor's liability therefor, Grantee, in its sole discretion, may apply any damages recovered to the
cost of undertaking any corrective action on the Property. If Grantee, in its sole discretion, determines
that circumstances require immediate action to prevent or mitigate significant damage to the
conservation values of the Property, Grantee may pursue its remedies under this paragraph without
prior notice to Grantor or without waiting for the period provided for cure to expire. Grantee's rights
under this paragraph apply equally in the event of either actual or threatened violations of the terms of
this Conservation Easement, and Grantor agrees that Grantee's remedies at law for any violation of
the terms of this Conservation Easement are inadequate and that Grantee shall be entitled to the
injunctive relief described in this paragraph, both prohibitive and mandatory, as well as specific
performance of the terms of this Conservation Easement, without the necessity of proving either actual
damages or the inadequacy of otherwise available legal remedies. Grantee's remedies described in this
paragraph shall be cumulative and shall be in addition to all remedies now or hereafter existing at law
or in equity.
B. Riaht of Entry: Grantee, its employees and agents, shall have the right to enter the
Property (including the concomitant right to cross the adjoining property of Grantor) at any reasonable
time for the purpose of preparing baseline documentation with respect to the Property and for
inspecting the Property to determine whether Grantor is complying with the terms, conditions, and --
restrictions of this Low Maintenance Conservation Easement.
C. Costs of Enforcement. Any costs incurred by Grantee in enforcing the terms of this
Conservation Easement against Grantor, including, without limitation, costs of suit and attorneys' fees,
and any costs of restoration necessitated by Grantor's violation of the term of this Conservation
Easement, shall be paid by Grantor. D. Grantee's Discretion. Enforcement of the terms of this Conservation Easement shall be
at the discretion of Grantee, and any forbearance by Grantee to exercise its rights hereunder shall not
be deemed or construed to be a waiver by Grantee of such term or of any subsequent breach of the
same or any other term of this Conservation Easement or of any of Grantee's rights hereunder. No
118

delay or omission by Grantee in the exercise of any right or remedy upon any breach by Grantor shall
impair such right or remedy or be construed as a waiver.
E. Acts Beyond Grantor's Control. Nothing contained in this Conservation Easement shall
be construed to entitle Grantee to bring any action against Grantor for any injury to or change in the
Property resulting from causes beyond Grantor's control, including, without limitation, fire, flood,
storm, and earth movement, or from any prudent action taken by Grantor under emergency conditions
to prevent, abate, or mitigate significant injury to the Property or to persons resulting from such causes.
ARTICLE VI. MISCELLANEOUS
A. Subsequent _Transfers. Grantor shall incorporate the terms of this Conservation
Easement in any deed or other legal instrument by which Grantor transfers any interest in the
Property, including, without limitation, any liens or leasehold interest. Grantor further agrees to give
written notice to Grantee of the proposed transfer of any interest at least thirty (30) days prior to the
date of such transfer. The failure of Grantor to perform any act required by this paragraph shall not
— impair the validity of this Conservation Easement or limit its enforceability in any way.
B. Successors. The covenants, terms, conditions, and restrictions of this Conservation
Easement shall be binding upon, and inure to the benefit of the parties hereto and their respective
personal representatives, heirs, successors, and assigns and shall continue as a servitude running in
perpetuity with the Property.
C. Counterparts. The parties may execute this instrument in two or more counterparts,
which shall, in the aggregate, be signed by both parties; each counterpart shall be deemed an original
... instrument as against any party who has signed it. In the event of any disparity between the
counterparts produced, the recorded counterpart shall be controlling.
D. Notices. Any notices shall be sent by registered or certified mail, return receipt
requested, addressed to the parties as set forth above, or to such other addresses such party may
establish in writing to the other. In any case where the terms of this Conservation Easement require
-- the consent of any party, such consent shall be requested by written notice. Such consent shall be
deemed denied unless, within thirty (30) days after receipt of notice, a written notice of approval and
the reason therefore has been mailed to the party requesting consent.
E. Amendments. Grantor and Grantee are free to jointly amend this Low Maintenance
Conservation Easement to meet changing conditions, provided that no amendment will be allowed that
is inconsistent with the purpose of this easement, affects the perpetual duration of this easement, the
status of Grantee under any applicable law. Such amendment(s) shall be effective upon recording in
the public records of County, North Carolina.
F. Costs and Liabilities. Grantor shall retain all responsibilities and shall bear all costs and
liabilities of any kind related to the ownership, operation, upkeep, and maintenance of the Property,
including, without limitation, the payment of all taxes and assessments levied on or assessed against
the Property by any competent authority and the maintenance of adequate comprehensive general
119

liability insurance coverage. Grantor shall keep the Property free of any liens arising out of any work
performed for, materials furnished to, or obligations incurred by, Grantor or anyone claiming under
Grantor.
TO HAVE AND TO HOLD the Conservation Easement unto Grantee, its successors and
assigns, forever.
IN WITNESS WHEREOF, Grantor and Grantee have executed this Conservation Easement,
each having adopted the type written word ("SEAL") as their personal/corporate seal, as of the day and
year first written above.
GRANTOR:
(SEAL)
(SEAL)
I, , a Notary Public in and for said County and State so hereby
certify that personally appeared before me this day and being
duly sworn, acknowledged that he/she executed the foregoing instrument for the purposes contained
within.
WITNESS my hand and official stamp or seal, this the day of ,
My Commission Expires:
Notary Public " 4
120

NORTH CAROLINA
COUNTY
I, , a Notary Public in and for said County and State so hereby
certify that personally appeared before me this day and being
duly sworn, acknowledged that he/she executed the foregoing instrument for the purposes contained
within.
WITNESS my hand and official stamp or seal, this the day of
Notary Public
My Commission Expires:
GRANTEE:
CITY OF ROCKY MOUNT
Accepted By:
Frederick E. Turnage - Mayor
ATTEST:
Jean M. Bailey — City Clerk
(SEAL)
121

ROCKYMOUNT/030163-953/221616 v_l
EXHIBIT A
CONSERVATION EASEMENT
DESCRIPTION
122

Appendix P. Ordinance Establishing Legal
Authority For Illegal Discharge Program
123

ARTICLE V. ILLEGAL DISCHARGES INTO THE STORMWATER SYSTEM
The Legislature of the State of North Carolina has designated specific local governments in the Tar
Pamlico River Basin and has required them to develop stormwater management in conformance with
15A NCAC 2B.0258, Tar -Pamlico River Basin -Nutrient Sensitive Waters Management Strategy.
This section is adopted pursuant to the authority contained in G.S. 113A Article 4 (Pollution Control
Act), G.S. 143 Article 21 (Water and Air Resources); G.S. 160A- 185 (Emission of pollutants or
contaminants) and the requirements of 15A NCAC 2B.0258. Any modifications to this section are
subject to the approval by the NC Division of Water Quality (DWQ).
Section 10-210. Purpose
(a) This chapter is adopted for the purposes of:
(1) Protecting the public health, safety and welfare by controlling the discharge of pollutants into
the stormwater conveyance system; ..
(2) Promoting activities directed toward the maintenance and improvement of surface and
ground water quality;
(3) Satisfying the requirements imposed upon the City of Rocky Mount under its National
Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer
System (MS4) Discharge Permit issued by the State, and the North Carolina
Department of Environment and Natural Resources Tar Pamlico Nutrient Management
Regulations.; and
(4) Establishing administration and enforcement procedures through which these purposes
can be fulfilled.
Section 10-211. Applicability
The terms of this ordinance shall apply only within the areas within the City limits and shall not apply
within the City's ETJ unless expressly approved in an agreement between the City and the appropriate
County.
Section 10-212. Acronyms
DENR: North Carolina Department of Environment and Natural Resources. -�
DWQ: North Carolina Division of Water Quality.
MS4: Municipal Separate Storm Sewer System.
NPDES: National Pollutant Discharge Elimination System
Section 10-213. Definitions:
As used in this chapter, unless the context clearly indicates otherwise, the following definitions apply:
Illicit Connection. Any physical connection, actual or potential flow discharge, or other condition,
which could permit non-stormwater to enter the stormwater conveyance system or waters of the State
in violation of this chapter.
124

Illicit Discharge. Any unlawful disposal, placement, emptying, dumping, spillage, leakage, pumping,
_ pouring, emission, or other discharge of any substance other than stormwater into a stormwater
conveyance, the waters of the State, or upon the land in such proximity to the same, such that the
substance is likely to reach a stormwater conveyance or the waters of the State.
Improper Disposal. The releasing of matter or fluids other than atmospheric precipitation at a location
where the matter or fluid can enter the stormwater system.
Municipal Separate Storm Sewer System (MS4). A stormwater conveyance or unified stormwater
conveyance system (including without limitation: roads with drainage systems, municipal streets, catch
basins, stormwater detention facilities, curbs, gutters, ditches, natural or man-made channels, or storm
drains), that:
(1) is located within the corporate limits of Rocky Mount, North Carolina; and
_ (2) is owned or operated by the State, County, the City, or other public body; and
(3) Discharges to waters of the State, excluding publicly owned treatment works, and lawful
connections thereto, which in turn discharge into the waters of the State.
National Pollutant Discharge Elimination System. A permitting system established pursuant to §402
of the Clean Water Act et seq.
Non-stormwater. Any flow, which is not from a form of natural precipitation
Pollution. Man-made or man -induced alteration of the chemical, physical, biological, thermal, and/or
radiological integrity of water.
Receiving Stream. The body of water, stream, or watercourse receiving the discharge waters from the
stormwater system, or formed by the water discharged from the stormwater system.
Stormwater. Any flow resulting from, and occurring during or following, any form of natural
precipitation.
Stormwater Conveyance or Stormwater Conveyance System. Any feature, natural or man-made, that
collects and transports stormwater, including but not limited to roads with drainage systems, streets,
catch basins, curbs, gutters, ditches, man-made and natural channels, pipes, culverts, and storm drains,
and any other natural or man-made feature or structure designed or used for collecting or conveying
stormwater.
Waters of the State. Any stream, river, brook, swamp, lake, sound, tidal estuary, bay, creek, reservoir,
waterway, or other body or accumulation of water, whether surface or underground, public or private,
or natural or artificial, that is contained in, flows through, or borders upon any portion of this State,
including any portion of the Atlantic Ocean over which the State has jurisdiction. Treatment systems,
consisting of man-made bodies of water, which were not originally created in waters of the State and
which are not the result of impoundment of waters of the State, are not waters of the State.
125

Section 10-214. Objectives
The objectives of this chapter are to:
(1) Regulate the discharge of substances which may contaminate or cause pollution of
stormwater, stormwater conveyances, or waters of the State;
(2) Regulate connections to the stormwater conveyance system;
(3) Provide for the proper handling of spills; and
(4) Provide for the enforcement of same.
Section 10-215. Non-Stormwater Discharge Controls
(a) Illicit Discharge
No person shall cause or allow the discharge, emission, disposal, pouring, or pumping directly
or indirectly to any stormwater conveyance, the waters of the State, or upon the land in such
proximity to the same (such that the substance is likely to reach a stormwater conveyance or the
waters of the State), any fluid, solid, gas, or other substance, other than stormwater; provided
that non-stormwater discharges associated with the following activities are allowed provided
that they do not significantly impact water quality:
(1) Dechlorinated filter backwash and draining associated with swimming pools;
(2) Filter backwash and draining associated with raw water intake screening and filtering
devices;
(3) Condensate from residential or commercial air conditioning;
(4) Residential vehicle washing;
(5) Flushing and hydrostatic testing water associated with utility distribution systems;
(6) Discharges associated with emergency removal and treatment activities, for hazardous
materials, authorized by the federal, State, or local government on -scene coordinator;
(7) Uncontaminated ground water [including the collection or pumping of springs, wells, or
rising ground water and ground water generated by well construction or other
construction activities];
(8) Collected infiltrated stormwater from foundation or footing drains;
(9) Collected ground water and infiltrated stormwater from basement or crawl space
pumps;
(10) Flows from springs, riparian habitats and wetlands;
(11) Irrigation water, including landscape irrigation and lawn watering;
(12) Street wash water;
(13) Flows from fire fighting;
(14) Discharges from the pumping, diverting or draining of natural watercourses or
waterbodies;
(15) Flushing and cleaning of stormwater conveyances with unmodified potable water;
(16) Wash water from the cleaning of the exterior of buildings, including gutters, provided
that the discharge does not pose an environmental or health threat;
(17) Other discharges from unmodified potable water sources; and
(18) Other non-stormwater discharges for which a valid NPDES discharge permit has been
approved and issued by DWQ, and provided that any such discharges to the municipal
separate storm sewer system shall be authorized by the City.
126

Illicit discharges include, but are not limited to, pipelines, ditches and overland flow carrying
non-stormwater flow from wastewater lines such as those from washing machines or sanitary
sewers, commercial wash water from cleaning vehicles or equipment, flushing water such as
that from industrial operations, floor drains, overflowing septic systems, and misuse of
fertilizers, pesticides and herbicides, oil, anti -freeze, chemicals, paints, garbage, and litter.
Any Illicit discharges into, or having the potential to be indirectly transported to, the
.� stormwater conveyance system shall be contained, controlled, collected, and removed
promptly. Any areas determined by the Director of Public Works or his designee to be damaged
as a result of said discharge shall be restored to their preexisting condition.
(b) Illicit Connections
(1) Connections to a stormwater conveyance or stormwater conveyance system which allow
the discharge of non-stormwater, other than the exclusions described in section (a) above,
are unlawful. Illicit connections include, but are not limited to: floor drains, waste water
from washing machines or sanitary sewers, wash water from commercial vehicle washing
or steam cleaning, and waste water from septic systems.
+' (2) Where such connections exist, and said connections were made prior to the adoption of this
provision or any other ordinance prohibiting such connections, the property owner or the
person using said connection shall remove the connection within one (1) year following
application of this regulation; provided that, this grace period shall not apply to connections
which may result in the discharge of hazardous materials or other discharges which pose an
immediate threat to health and safety, or are likely to result in immediate injury and harm to
real or personal property, natural resources, wildlife, or habitat.
(3) Where it is determined that said connection was made in violation of any applicable
regulation or ordinance or where said connection may result in the discharge of hazardous
materials or may pose an immediate threat to health and safety, or is likely to result in
immediate injury and harm to real or personal property, natural resources, wildlife, or
habitat, the Director of Public Works or his designee shall designate the time within which
the connection shall be removed. In setting the time limit for compliance, the City shall take
into consideration:
^" a. The quantity and complexity of the work,
b. The consequences of delay,
c. The potential harm to the environment, to the public health, and to public and private
property, and
d. The cost of remedying the damage.
t,
(c) Improper Storage and Disposal
Polluting substances, which may be harmful to biological life, shall not be stored or disposed of
in or near the stormwater system or at a location exposed to wind or rain, which could transport
127

the substances to the stormwater system. Prohibited substances include, but are not limited to,
oil, grease, fertilizer, household, and industrial chemical waste.
(d) Hazardous Material Spills and Discharges
Persons associated with the spill or leak of hazardous materials shall immediately notify the
City of Rocky Mount Fire Chief or his designee in accordance with the provisions of City Code
Article IV, Hazardous Material and Substance Abatement. Notification shall not relieve any
person of any expenses related to the restoration, loss, damage, or any other liability which may
be incurred as a result of said spill or leak, nor shall such notification relieve any person from
other liability which may be imposed by State or other law.
(e) Solid Waste, Yard Waste and Other Obstructions
(1) It shall be unlawful for any person to throw, dump, roll or in any manner place or cause to
be placed any objects or materials in a drainage pipe, culvert, drainage ditch or any other
stormwater carrier receiving street runoff which may cause a blockage, reduction in flow
capacity or build up of excess nutrients or pollutants. These objects and materials include
but are not limited to leaves, pine straw, grass clippings, tree limbs, lumber, construction
and landscaping debris, bulky items or any other type of solid waste capable of causing an
obstruction or otherwise degrading water quality and/or the stormwater conveyance system.
(2) The Director of Public Works or his representative may grant temporary authority to block
or obstruct a drainage system for construction, repair or maintenance activity. This --
temporary authority is for limited duration and does not relieve the grantee of responsibility
for any damages caused by such blockage or obstruction.
Section 10-216. Enforcement
(a) Powers and authorityfar inspection and correction
City personnel or other duly authorized representative(s), bearing proper identification, shall be
permitted to enter upon all properties for the purpose of inspection, observation, measurement,
sampling and testing in accordance with the provisions of this article. No person shall obstruct,
hamper, or interfere with any such representative while carrying out official duties. If an illicit
connection is found or evidence of an illicit discharge or improper disposal is found, City ^'
personnel or other duly authorized representative bearing proper identification shall be
permitted to enter upon all properties for the purpose of determining the corrective actions
required for said violations including but not limited to removal of said violations and -'
restoration or repair of any damages caused by said violations. If the required actions are not
completed within the time period specified in the notice of violation the property owner will
^
become subject to further enforcement action in accordance with the provisions of this section.
(b) Civil Penalties
(1) Illicit Discharges
128

Any designer, engineer, contractor, agent, or any other person who allows, acts in
concert with, participates, directs, or assists directly or indirectly in the creation of a
violation of this chapter shall be subject to civil penalties as follows:
a. For first time offenders, if the quantity of the discharge is equal to or less than five
(5) gallons and consists of domestic or household products in quantities considered
ordinary for household purposes, said person shall be assessed a civil penalty not to
exceed one hundred dollars ($100.00) per violation or per day for any continuing
violation, and if the quantity of the discharge is greater than five (5) gallons or
contains non -domestic substances, including but not limited to process waste water,
or if said person cannot provide clear and convincing evidence of the volume and
nature of the substance discharged, said person shall be assessed a civil penalty not
to exceed one thousand dollars ($1,000.00) per violation or per day for any
continuing violation.
b. For repeat offenders, the amount of the penalty shall be double the amount assessed
for the previous penalty, not to exceed ten thousand dollars ($10,000.00) per
violation or per day for any continuing violation.
c. in determining the amount of the penalty, the City Manager or his/her designee shall
consider:
1. The degree and extent of harm to the environment, the public health, and public
and private property;
2. The cost of remedying the damage;
3. The duration of the violation;
4. Whether the violation was willful;
5. The prior record of the person responsible for the violation in complying or
failing to comply with this chapter;
-- 6. The costs of enforcement to the public; and
7. The amount of money saved by the violator through his, her, or its
noncompliance.
(2) Illicit Connection.
Any person found with an illicit connection in violation of this chapter and any
-- designer, engineer, contractor, agent, or any other person who allows, acts in concert,
participates, directs, or assists directly or indirectly in the establishment of an illicit
connection in violation of this chapter, shall be subject to civil penalties as follows:
.� a. First time offenders shall be subject to a civil penalty not to exceed five hundred
dollars ($500.00) per day of continuing violation.
b. Repeat violators shall be subject to a civil penalty not to exceed one thousand
dollars ($1,000.00) per day of continuing violation.
C. In determining the amount of the penalty, the City Manager or his designee shall
consider:
1. The degree and extent of harm to the environment, the public health, and
public and private property;
2. The cost of remedying the damage;
3. The duration of the violation;
4. Whether the violation was willful;
•- 129

S. The prior record of the person responsible for the violation in complying or
failing to comply with this chapter;
6. The costs of enforcement to the public; and
7. The amount of money saved by the violator through his, her, or its
noncompliance.
(3). Procedures for assessing penalties pursuant to violations of this Article.
Said penalties shall be assessed by the Director of Public Works or his designee. No
penalty shall be assessed until the person alleged to be in violation is served written
notice of the violation by registered mail, certified mail -return receipt requested, or
personal service. Refusal to accept the notice shall not relieve the violator of the
obligation to pay the penalty. The notice shall describe the violation with particularity
and specify the measures needed to come into compliance. The notice shall designate
the time within which such measures must be completed. In setting the time limit for
compliance, the City shall take into consideration:
I . The quantity and complexity of the work;
2. The consequences of delay;
3. The potential harm to the environment, the public health, and public and
private property; and
4. The cost of remedying the damage.
The notice shall warn that failure to correct the violation within the specified time
period will result in the assessment of a civil penalty and/or other enforcement action. If
after the allotted time period has expired, and the violation has not been corrected, the
penalty shall be assessed from the date of receipt of notice of violation and each day of .�
continuing violation thereafter shall constitute a separate violation under this section.
(3) Other violations ._
Any person found in violation of other provisions of this chapter, not specifically
enumerated elsewhere, shall be subject to a civil penalty not to exceed one hundred
dollars ($100.00) per violation or per day for any continuing violation.
(4) PaymentlCollection Procedures
The Director of Public Works or his/her designee shall make written demand for -,
payment upon the person in violation. If the payment of the penalty assessed under
section 216(b)(3) is not received or an equitable settlement reached within thirty (30)
days after demand for payment is made, the matter shall be referred to the City Attorney for institution of a civil action in the name of the City, in the appropriate division of the
general court of justice in Nash or Edgecombe County, as appropriate, for recovering
the penalty.
(c) Injunctive Relief
(1) Whenever the City Manager has a reasonable cause to believe that any person is
violating or threatening to violate this chapter, rule, regulation, order duly adopted or
issued pursuant to this chapter or making a connection to a stormwater conveyance or
stormwater conveyance system other than in accordance with the terms, conditions, and
provisions of approval, the City may, either before or after the institution of any other
130

action or proceeding authorized by the Code, institute a civil action in the name of the
City for injunctive relief to restrain and abate the violation or threatened violation.
(2) The institution of an action for injunctive relief under subsection (c) shall not relieve
any party to such proceeding from any further civil or criminal penalty prescribed for
violations of this Code.
.w
(d) Criminal Penalties
Any person who knowingly or willfully violates any provision of this chapter, rule, regulation,
order duly adopted or issued pursuant to this chapter shall be guilty of a misdemeanor,
punishable by a fine not to exceed five hundred dollars ($500.00) or imprisonment for not
longer than thirty (30) days. Each violation shall be a separate offense.
(e) Corrective Actions by the City
If the party that receives a notice as described above fails, neglects, or refuses to remedy the
condition(s) outlined in the notice within the time specified in the notice, the Public Works
Director or designee may elect to enter the property and cause such condition to be removed,
abated or remedied in order to prevent further damage or escalation of the cost to remedy the
violation. The cost of such action shall be paid by the owner of the property or other
responsible party and if not paid shall be a lien against the real estate or premises upon which
the illicit connection was constructed or improper occurred and shall be collected as unpaid
taxes. The initiation of such actions by the City does not relieve the offending party of any
liability for fines or criminal penalties related to the offense.
131

Appendix Q. Illicit Discharge Screening Report
Forms
Field Screening Report
General Information
Sheet Number
Outfall ID Number
Date
Time
Date, Time and Quanti
of Last Rainfall Event
Field Site Description
Location
Type of Outfall
Dominant Watershed Land Use(s)
Visual Observations
Photograph
Deposits/Stains
Odor
Vegetation Condition
Color
Structural Condition
Clarity
Biological
Floatables
Flow Estimation
Sampling Analysis `
Temperature
Nitrogen-Nitrate/Nitrite
pH
Fluoride or Chlorine
Nitrogen -Ammonia
Total Phosphorus
Ortho-Phosphate
* Analytical monitoring is required only if an obvious source of the dry weather flow cannot be
determined through an investigation of the upstream stormwater collection system.
132

Appendix R. List of Education Resources
Education Activity Options for Tar -Pamlico Local Programs
VWIN Water Quality Monitoring Program
This is a Volunteer Water Information Network, a program which allows volunteers to collect water
samples, and send them to the lab for certified laboratory analysis. The cost of the program is $4500
per year, for a 10 site program plus about $300 - $500 per year for 2-day shipment of samples.
Contact: UNC-Asheville, Asheville, NC 28804
Dr. Rick Maas, EQI Research Director
[phone] [e-mail]
Marilyn Westphal, V WIN Coordinator
[phone] mwestphal2unca.edu
Home*A*Syst
Homeowner self -assessments developed by the Cooperative Extension Service for a variety of home
activities, including protecting your water quality and your septic system.
Grace Lawrence, Extension Associate
Department of Soil Science, NC State University
[phone] grace _lawrence [e-mail]
www.soil.ncsu.edu/assist
• a local government can link their website to this website, and receive educational points for each
year that the link is in effect
• a local government could use a Home*A*Syst presentation in their workshops
0 a local government could have publications available for the public, and / or distribute
packages to new homeowners.
Adopt -A Stream
www. adopt -a- stream or
Funding Resources
NOAA Grants
www.rde,noaa.gov/—grants/index.htmi
North Carolina `319' Nonpoint Source Grant Program
._ Funds innovative BMP demonstration and education efforts, as well as watershed restoration projects.
httt,://h2o.enr.state,ne.us/nps/Section_319 Grant_Program.htm
NC Clean Water Management Trust Fund
http://www.cwmtf net/
133

State Stormwater Programs under
NC Department of Environment & Natural Resources
• Tar -Pamlico Nutrient Strategy
The NC Division of Water Quality web site for the Tar -Pamlico nutrient strategy. Includes a
history and status of the strategy and its elements, both point and nonpoint source, as well as links
to rules and supporting information. This model and appendices are also available on the site. ^
http://h2o.enr.state.nc.us/nps/tar-pam.htm
■ Neuse Local Stormwater Programs
• Town of Cary
www.townofcar .or de is/dsde t/enginecri❑ en rot/stonnwater/stormwatermain.htm
• Orange County
www.co.oran e,nc.us/p1qnningLerosion.btm
Division of Water Quality Stormwater and General Permits Unit
Includes links to the Neuse stormwater model and Neuse local programs, information on Phase I
and II NPDES Stormwater programs, the State Stormwater Management Program (coastal, ORW, ..,
and HQW), stormwater manuals and other resources, and useful links.
h2o.enr.state.ne.us/su/stormwater.htmI
• Division of Water Quality, Nonpoint Source Management Program
Includes Tar -Pamlico and Neuse nutrient strategies, the NC Coastal Nonpoint Source Program, the
Section 319 grant program, information about nonpoint source pollution, other programs and links.
h2o.enr.state.nc.us/nps/
NC Water Supply Watershed Program -,
The oversight program for local water supply ordinances. Includes links to local programs, model
ordinances, forms, and fact sheets, the Streamlines newsletter that details program options and
discusses salient issues, and other information. --
h2o. enr. state. ncus/wswp/index. html
• Office of Environmental Education --
www.ee.enr.state.ne.us/Index.htm
Division of Water Resources, --
Includes links to Stream Watch & Project Wet, and a slide presentation on SMPs
www. dwr. ehnr. state. nc. us
www.dwr.ehnr.state.nc.us/Reports_and_Publications/Stream_Watchibmps.pdf ^
■ Albemarle -Pamlico National Estuary Program (APNEP)
Includes information on the Citizen's Water Quality Monitoring Program (CWQMP)
h2O.enr.state.nc.us/nep/
134

Low Impact Development
Maryland Stormwater Management Program
Home page explains impacts of runoff and steps individuals can take to help. It also has links to homeowner and other
materials including a model stormwater ordinance and technical manuals, including the Maryland Stormwater Design
Manual
www.mde.state.md.us/Pro.erams/WaterPropams/SedimentandStomwater/home.index.as
'~ Low Impact Development Program, Prince George's County, Maryland
The originators of LID. includes links to their LID manuals and bioretention info.
www.co. .md.us/Government/A enc Index/DER/PPD/lid.as ?h=20&s=&n=50&nl=160
Low Impact Development Center, Inc.
Non -Profit whose mission is to "provide information to individuals and organizations dedicated to protecting the
environment and our water resources through proper site design techniques that replicate pre-existing hydrologic site
conditions".
www.lowimpactdevelopment.org
Stormwater Strategies: Community Responses to Runoff Pollution
This Natural Resources Defense Council report, originally published in 1999, was updated in 2001 with a chapter on
Low Impact Development.
www.nrdc.or water/pollution/stormistoinx.asp
Smart Growth
NOAA Smart Coastal Growth
Includes links to smart growth documents and organizations
www.csc.noaa.jzov/themes/communities
Smart Growth America
A nationwide coalition of over 80 national and local organizations promoting a better way to grow: one that protects
farmland and open space, revitalizes neighborhoods, keeps housing affordable, and provides more transportation
choices.
www.smartgrowthamerica.com
USEPA Office of Smart Growth
Information including initiatives, events, publications, and helpful links.
www.epa,P-oy/srnartg[owth/index.htm
Congress for the New Urbanism
www.cnu.oru
Smart Growth Network
In 1996, the US EPA joined with several non-profit and government organizations to form the Smart Growth Network
(SGN). The Network was formed in response to increasing community concerns about the need for new ways to grow
that boost the economy, protect the environment, and enhance community vitality. The Network's partners include
environmental groups, historic preservation organizations, professional organizations, developers, real estate interests,
Iocal and state government entities.
www.smartgrowth.org/default.asp

Broad Stormwater Information
Storm Water Strategies
To help communities implement better storm water controls, the Natural Resources Defense Council
(NRDC) recently released a CD-ROM version of its 1999 report, Storm Water Strategies: Community
Responses to Run-off Pollution. The new CD-ROM is very user-friendly and includes updated case
studies on storm water management issues (including new information on Low Impact Development),
and web site links to storm water leaders across the country. For more information:
www.nrde.org/ publications
212-727-2700.
NCSU Stormwater Education
The web site of North Carolina State University stormwater specialist and Biological and Agricultural
Engineering faculty member Bill Hunt that includes:
■ general and specific stormwater management training,
■ upcoming stormwater education events,
■ online and regular university courses,
■ stormwater publications.
www.bae.ncsu.edu/people/faculty/hunt
NCSU Water Quality Group
Exclusively focused on nonpoint source pollution, this site includes a wealth of information on the
subject, including a searchable, annotated bibliography of NPS literature, a watershed management
decision support system, an education component with extensive information on BMPs for different
NPS categories, and extensive links.
www.bae.ncsu.edu/t)rograms/extension/wqg/index.html
NCSU Water Quality Program
A web site with information and links on all aspects of water quality protection and management.
www.water.ncsu.edu
USEPA Office of Water — Urban Stormwater page
Urban Stormwater Runoff Program includes model ordinances, economic benefits of prevention, and ^,
program development guides.
www.e,pa.gov/owow/nps/urbarLhtml
Army Corps of Engineers
Includes information on Navigation, Flood Damage Reduction, Environmental Missions, Wetlands and
Waterways Regulation and Permitting, Water Supply and Public Services.
www.usace.arrnv.mil/
www.usace.army.mil/public.html#Navigation
136

Center for Watershed Protection
A non-profit stormwater education organization out of Maryland. Site offers an abundance of
information on the management of stormwater, including "The Importance of Imperviousness" and
"The Peculiarities of Imperviousness" by Tom Schueler, and links to other reports.
www.cwp.org
Stormwater Center Website
Supported by the Center for Watershed Protection, the site offers information about watershed and
stormwater planning, including free example stormwater maintenance agreements and slideshows for
viewing and purchase.
http://www.storrnwatercenter.net/
NC Cooperative Extension Service
Centered at North Carolina State University, the NC Cooperative Extension Service offers a variety of
.. educational information useful to local governments, industry, businesses and homeowners. The site
includes links to county Extension offices across the state.
www.ces.nesu.edu
Stormwater Magazine
Includes information from. Stormwater Publications, including a search feature allowing the reader to
search for articles of interest
www.stormh2o.com
Pamlico Tar River Foundation
The Pamlico -Tar River Foundation was founded in 1981. It is a private, non-profit organization
dedicated to protecting, preserving and promoting the environmental quality of the
Tar -Pamlico River and its watershed. PTRF is a grassroots organization, supported by nearly 1,500
citizen members -- "River Givers." PTRF achieves its mission through education, advocacy, and
research.
www.ptrf.org
137

a)
`�
o
`fl
ko
�
`sr
w U
N
`09-
N
N
ao1
m
vU o
c
a o
a'
It
OD
N
N
Nr
Cl)
w
N
�
_c CD
u
m
O U
�
•fl
o
r
to
O
CD
Q
o
b
C)
U
�
d
N
m
C
�
Oa.
m
43
[n
JAI
u
'°
d
m
C I
o
V
Qf
rn
Q
0 v
C9
m
O
C
m
42
1
y
u,
Ewa
i
.0
S
L
CO
CO
(9
L
lG
L
CO
L
w
L
m
L
m
L
m
L
m
L
m
L
m
L
0UODOU
tJ
C
m
W
m
m
m9+
?+
T
T
T
T
T
}
wwwwo+
O
O
O yr
a
b
m
in
m
Gf C
0
a
m
cm
ro
a
o
�
a•o�
y
..
CL
aV
Gi
u
o
E
cc
�'
a
u a
Li
Q
C
—
m
Q
N
m
3
p
CQ
c
m
O
._[
O
a
d
`
m
m
fi CDN
G
CO
m
N
j,
LL
Z
O
C
ld
Q
N
w
O
67
o
'�
�•
p
m
VI
�+
C
m
w O
Q
>
a
Z
7
m
3
E
`�
c
o
v
u
=
O
CV
L
L
c
O
H
z
O
E
d
d
c
+uc
A?
U
(aLn
CvICEJL06Oa.1
LL
O
Y
C
w
_
?
N
0
%a
C
N
Q
M
6)
�
r
CoU
U
w•U�^)
'
cn
�
Q
rL
oom
�_
m
nC"
s
O
c
m
Ca
o
w
�
cn m
E
LL
a)
o
fi
'0
W
CL
Y
y
O
a
Oy
.�a
O
NO
La
m
•
NCY)
— O�
•�
C
O
W
p
U
'O
U
C
Z
m
U
C
in
d
m
w93
Lo
N
m
0
C
2�
N
m
U
~
d
'O
O
C
O
cm
C
a
r
Q
O
w
m
Gm1
L
4
Q
4
Yma'
O
aEi
c14i
m
o
o
f
2
Z
+°� m
a
J
H
W
Q
U
d
LL
U
cg
cn
=
HLi-
O
Z +moo
cn
N
M
t0
CD
h
OD
6f
O
r
N
[+'3
"j I
CO I
f`
a0
m

c(D
ca)
U
U
CO
cO
o o
vi�
i
o o
�+
ai
f4 n
a
O iLn
N �
[
fH:
a i0
CN
64 :69
Q
U
O
� U
c
Q
t€ v
CD Lo rn
rn : rn
m
N iN
dNio
a pp
m
E E
o
S O
O
�
E;E
p
❑
❑ S9
N
r
a
lL
W
; i
E2
N
N E
G.:
_O
N
E
N
L
U
C7
❑
.0 i_U
f9 i
m
ma
a €a
o
c;
m m
v;
CM
`' C
a
Q
O 0
i
SO
i
w o
c
N '
i
C7 iC7
•�=
7
CO.
LU O
(9 l>
U
N
i
H
i
i
r
Q
a
o
Q
o
�
c+-
a
c
a
C
U
o
�
i
(
au)
3
o❑
o❑
o:U)
mcoo:o
cc
Q : o.
rn
m
❑0
0
7
i N
f6 i VI
O i
UCL
jL
: O
U i U
G7 i 41
I- :H
0? i N
Z 3
o t-p
6 €Q
r0 t
CA
41
M

Appendix T.
City of Rocky Mount
Tar -Pamlico River Basin:
Stormwater Program
for Nutrient Control
New Development Annual Report Form
BMP Review, Approval and Maintenance
140

City of Rocky Mount: Annual Report
New Development BMP Review, Approval and Maintenance
(a) Development Activity Summary
FY 2004-5 (July 1 through June 30)
knoe-
.............
roy-W
lact: p Tbihore C
Public/Private Vr7l;
Sinlge Family/Duplex NA
Multi -Family
Non-residential
Total
Stormater BMP Summary Table
un-�iTe b M FS ADDrovea
T W 81m, R' " I 9 -;"; � W '. "CIN
, . I PI
'0 tl��I
N W"
Wet Detention Pond
Stormwater Wetland
Sand Filter
Bioretention
Grass Swale
Vegetated Filter Strip w/ L
Spread
Conserv. Easement
Open Space Easement
Total
',J I I -Q I LW UIWIF 0 IVVCII
Wet Detention Pond
Stormwater Wetland
Bioretention
Grass Swale
Vegetated Filter Strip w/ L
Spread
Conserv. Easement
lOpen Space Easement
[Total
... ...... .
Nn%
Total Pre-Deveoped Export
Total Post-Deveoped Export
141

(b) BMP Maintenance
Number of Inspections:
Number of BMP Failures:
Number of Enforcement Actions:
(c) Summary of maintenance activities conducted on BMPs.
(d) Summary of any BMP failures and how they were handled.
(e) Summary of results from any applicable jurisdictional review of planning issues.
(0 Summary of Program administrative changes, updates.
(g) Implementation Schedule Status
2004
2005
2006
J
F
M
A
M
J
J
A
S
O
N
D
1
2
3
4
1
2
3
4
Resolution of Support
Update Design Manual
.
, it
�
EngineerslDevelopers Workshop
Ordinance Adoption
Public Education/Outreach
Stormwater Hotline
7C'?
V)o
C
Mapping
s
ie
"kr
x
Illegal Discharge Screening
z=''
Retrofit Locations
Ax
AnnualReport
142