WSMU_DURH_Ordinance Proposed Revisions_20190301

AN ORDINANCE AMENDING THE STORMWATER PERFORMANCE STANDARDS
FOR DEVELOPMENT, DURHAM CITY CODE CHAPTER 70, ARTICLE X,
SECTIONS 70-736 THROUGH 70-749744
WHEREAS the City Council of the City of Durham finds that:
The health, safety -and, general welfare and convenience of the public will be furthered through:
1) Protecting receiving waters impacted by stormwater runoff discharged from
development within the City of Durham through maintaining performance standards
for total suspended solids;(TSS nitrogen, phosphorus, and bacteria for such
development;
2) Complying with the City of Durham's municipal stormwater National Pollutant
Discharge Elimination System permit, issued under the authority of Section 402(p)
of the Clean Water Act and implementing regulations at 40 CFR Part 122.26 et seq.;
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3) Complying with the General Statutes of North Carolina, including but not limited to
Article 4A 113A-70 et seq. and with implementing regulations for such state
statutes, including but not limited to the statutes and regulations implementing
nutrient management requirements i*for the Neuse; Basin and the Falls; Basin, and
r,,,-,a B
4) Limiting potential flooding of downstream properties and protecting streams and
other waterways from erosion by ensuring that development manages the increases
in peak flows that result from changes in land cover_
NOW, THEREFORE, BE IT ORDAINED, by the City Council of the City of Durham that:
SECTION 1. Existing Sections 70-736 through 70-7-44-744 are ,-orhw-e,a and amended as
follows:

—`Sec. 70-736. Purpose and definitions.
(a) Purpose. The purpose of Article -X is to further the health, safety-, general welfare
and convenience of the public through:
(1) Protecting receiving waters impacted by stormwater runoff discharged from
development within the City of Durham through maintaining performance standards
for total suspended solids;_(TSSJ nitrogen, phosphorus, and bacteria for such
development;
(2) Complying with the City of Durham's municipal stormwater National Pollutant
Discharge Elimination System permit, issued under the authority of Section 402(p) of
the Clean Water Act and implementing regulations at 40 CFR Part 122.26 et seq.;
(3)-Complying with the various General Statutes of North Carolina -including but not
limited to Article 4A, GS 113A-70 et seq. and- implementing regulations for such
state statutes, including but not limited to the statutes and regulations implementing
nutrient management requirements i*for the Neuse; Basin and the Falls; Basin; and
efd b
(4) Limiting potential flooding of downstream properties and protecting streams and
other waterways from erosion by ensuring that development manages the increases in
peak flows that result from changes in land cover_
(b) Definitions. Within this Article, the following terms and phrases, regardless of
capitalization, shall have the meanings set forth below:
Baseline Date or Applicable Baseline Date means the following dates when stormwater
requirements were adopted for the basins indicated:
Jordan Basin Dee. 31, 20"March 77, 2009
Falls Basin Dec. 31, 2006July 6, 2012
Lower Neuse Basin March 9, 2001
City Stormwater Standards means written standards related to Stormwater adopted by the
Public Works- Department or City Council. They include but are not limited to:
the Reference Guide for Development and Reference G ide^ontent published for
e public's viewing and inspection; other written and adopted
specifications for the design, construction, maintenance, and operation of Stormwater Control
Measures or Stormwater Conveyances; and all state standards related to stormwater or state
approved alternatives to such standards that have been adopted by the City's T epal4fne t of
Public Works- Department or City Council. The City shall submit to 93AIQNC DEQ for
approval all technical standards that require approval_
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Common Plan of Development means staged or coordinated Development pursuant to an
approved plan such as a development plan or site plan whether or not by the same owner, or
successive improvements over a period of years initiated by the owner(s) of and conducted on a
parcel or contiguous parcels of land for the benefit of such parcel(s). Factors to be considered in
determining whether a Common Plan of Development exists include but are not limited to:
ownership; scope, content, and history of approved plans; other information regarding the
development such as contracts, advertisements, or marketing materials; -equitable factors; and
common or joint use of infrastructure such as roads or utilities.
Department means the Depa4ment ublic Works Department of the City of Durham.
Development means hand r,:s44a-nee wh"any land-disturbingactivity that increases
„ faee on a pfepeft,the amount of Impervious Surface area or afteFS 4S 106*1
that otherwise decreases the
infiltration of precipitation into the :eil. 14 ine't�bet-h-subsoil. When additional development
occurs at a site that has existing development, the Impervious Surface area of the existing
development shall not be included in the density calculations for additional stormwater control
requirements, and newdevelopmext. 14 does not inelude aoeti r f,,,-os4y
aesstormwater control reauirements cannot be abblied retroactivelv to existing
development.
Director means the Director of the Public Works Department of the City of Durham, or such
person(s) as designated in writing by the Director to perform all or a portion of the functions set
forth in this Article.
Department of xEnvironmental Quality or D"DEQ means the men
,:North Carolina Department of the E*vi -,.rm ent and N ta+ l Des effFeesEnvironmental
uali (NC ODE ).
Downtown Area means the Downtown Tier, Compact Neighborhoods, and Suburban Transit
Zones as shown on the Durham Comprehensive Land Use Plan most recently approved by the
Durham City Council.
Existing Development means Development that, prior to the effective date of this ordinance
has either been lawfully constructed, or has established a vested right under North Carolina law
to construct a proposed project, or portion thereof. With regard to application of this ordinance,
a vested right will be recognized as follows:
a) for Development that does not require a state permit, a vested right shall exist for any
portion of a Development that has an approved or a completed application for a site plan or
subdivision plat covering that portion, -or in the event a site plan or subdivision plat is not
required, a building permit or a construction drawing for that portion of the Development. An
approved development plan does not accord vested rights in the absence of an approved or
completed application for the above -described plans or permits. A "completed application" is
one that meets all application requirements, including payment of all required fees and
submission of all required information, prior to the effective date of this ordinance. A vested
right shall expire if the validity of an approved or completed application or approval is not
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continuously maintained as otherwise required under the Unified Development Ordinance or
City Code;
b) for Development- that requires a state permit, vested rights shall be recognized if the
project meets all the requirements of a) above, and additionally has received necessary state
permits required for the use or for construction.
Falls Basin means the area that drains to the Falls Reservoir as determined by the Durham
Ci .-Count3LPlanning Department.
Impervious Surface means a surface that because of its composition and/or its use impedes
the natural infiltration of water. It includes but is not limited to buildings, roofs, solid decks,
driveways, parking areas, patios, sidewalks, and compacted gravel areas. It does not include
areas that are part of permitted storm -water controls Or the open „-eke wateF Stieh
peel; the open surface water such as swimming pools, a surface of 57 stone, as designated by
the American Society for Testing and Materials, laid at least four inches thick over a geotextile
fabric, a trail as defined in G.S. 113A-85 that is either unpaved or paved as longas s the pavement
is porous with a hydraulic conductivily greater than 0.001 centimeters per second (1.41 inches
per hour), or landscaping material, including, but not limited to, gravel, mulch, sand, and
vegetation, placed on areas that receive pedestrian or bicycle traffic or on portions of driveway
and parking areas that will not be compacted by the weight of a vehicle, such as the area between
sections of pavement that support the weight of a vehicle. The owner or developer of a property
mayopt out of any of the exemptions from "impervious surface" set out in this definition.
Jordan Basin means the area that drains to Jordan Lake as determined by the Durham Cfty-
Counly Planning Department.
Land Disturbance means a change in thermal cover or topography of land that may result
in sedimentation, and includes but is not limited to grubbing, stump removal, removal of topsoil,
coarse or fine grading, and disc „-ba-nee teex sure of the subgrade.
Limited Residential means single family and duplex residential and recreational
development.
Lower Neuse Basin means the area that drains to the Neuse River but not to the Falls Basin
as determined by the Durham City-County_Planning Department, whieh afea is genet lly shoo ,,
Multifamily and Other Development means development not included in Limited
Residential, and includes but is not limited to multifamily andresidential development (e.g.,
townhomes, :condominiums, apartments) , office, industrial, institutional (including local
government institutional), and commercial development.
New Development means Development that does not qualify as "Existing Development."
Redevelopment means Developmen any land-disturbingactivity ctivity that does not result in a
to ..,he fe 4p&affesnet increase in Impervious Surface area and that provides greater or
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. . . Tsuffaee already exist. 14 is aeategeryequal stormwater control to that of Piewthe
previous development.
Stormwater Control Measure, or SCM, means a device or practice that is designed to trap,
settle out, filter, or otherwise reduce pollutants from stormwater runoff, and/or to alter or reduce
runoff velocity, amount, timing, or other stormwater characteristics. The term includes all
measures formerly known as "best management practices" or "BMPs". Such measures include
but are not limited to stormwater detention facilities, constructed wetlands, bioretention areas,
sand filters, rainwater harvesting, systems, vegetative areas, level spreaders, filter strips, buffers,
aPA-vegetated swales, and appurtenant drainage facilities.
SCMMaintenance Certi ier means a North Carolina licensed professional engineer or North
Carolina registered landscape architect that has demonstrated to the Department's satisfaction
that they meet or exceed minimum knowledge and experience criteria for maintenance and
inspection of Stormwater Control Measures as detailed in City Stormwater Standards. This
individual is conditionally approved by the Department by formal issuance of a certificate. This
individual is authorized to conduct annual maintenance inspections of Stormwater Control
Measures, prepare findings, and submit annual maintenance inspection reports in accordance
with City Stormwater Standards.
Stormwater Conveyance means a physical feature, including constructed devices, that
conveys Stormwater. -A conveyance may also serve as a Stormwater Control Measure.
Stormwater Facilities means Stormwater Control Measures and Stormwater Conveyances.
Stormwater Pollutant or Pollutant -means nutrients (nitrogen and phosphorus), bacteria,
total suspended solids7-(ISSI and any other substance that can be transported via stormwater and
that is identified in this Article or City Stormwater Standards as requiring regulation.
Sec. 70-737_ General; prior requirements; additional standards;- interpretations.
(a) Applicability. -This Article ^^provides requirements for the control of Stefmwate
PaI Stormwater discharges containing stormwater pollutants and the management of
stormwater peak flows from sto f,,..,ate f diseha -gee f em Devel pment i developments within
the City of Durham. All Development shall be subject to the requirements of this Article unless
specifically exempted.
(b) Approval eentingeupon ezeContingent Upon Compliance. No site plan,
preliminary or final subdivision plat, construction drawing for a street or for utilities, or utility
permit shall be approved until the applicant has submitted information required by the City
Stormwater Standards sufficient to determine compliance with this Article, and review for
compliance has been conducted.
(c)-PriorTeqHir-etnents, Welations eeRequirements. Violations Continue. Prior
stormwater requirements that have been superseded by the requirements of this Article shall
continue to apply to Existing Development approved and/or constructed under such prior
requirements, in the event that the requirements of this Article do not apply. Existing
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Development, or portions thereof, that is not required to comply with this Article must continue
to manage Stormwater Pollutants and peak flow in accordance with the stormwater requirements
appearing on approved plans for the development and the requirements in effect when such plans
were approved. Violations of superseded stormwater requirements shall continue as violations
and be subject to enforcement under this Article unless this Article explicitly allows the
Development or action that constitutes the violation.
(d) City Stormwater Standards. The Public Works Department is authorized
to promulgate technical standards for use in the administration of this Article, which standards
may be amended from time to time. Technical standards may include but are not limited to
requirements for design, construction, performance, financial security, review, and professional
certification of stormwater facilities. City Stormwater Standards are considered requirements of
this Article. They shall be in writing, -ate approved and signed by the Director, and shall be
maintained in the City's Reference Guide for Development or in other written documents. —If
such standards conflict with technical standards that have been adopted pursuant to other
portions of the City Code, the Director shall be authorized to resolve such conflicts. Any such
resolution shall be consistent with the requirements of this Article. The City shall submit to
DWQNLDEQ for approval all technical standards that require approval.
-(e) -Maps. The watershed maps for the Falls Basin, the Jordan Basin, and the Lower Neuse
Basin maintained by the Durham City -=County Planning Department, as supplemented by
particular drainage information that may be required pursuant to City Stormwater Standards or
the Unified Development Ordinance, shall be used to determine the drainage basin in which a
property is located and other determinations regarding drainage.
(f) Final -'^^.g.i^Mg%toter-p-etations. Decisions/Interpretations. The Director shall be
authorized to render all interpretations of, and final decisions under, this Article. —No
interpretation shall be binding unless it is in writing and signed by the Director.
(g) -Requirements Supplementary; Conflict. -The requirements in this Article implement
and in some cases supplement other statutory; and regulatory, n e�� requirements
including, but not limited to, requirements for buffers, water protection (watershed) overlays, and
controls for sedimentation and erosion that are contained in the Durham City -County Unified
Development Ordinance. In the event of a conflict between the requirements of this Article and
sueh ethe statutoryregulatory requirements, the s*rie*er of thestatutory or reug lato1y
requirements shall control. In ,,, difie this ^ t4iele does not prohibit establishing s4ietef
(h) Fees. The City is authorized to charge fees to recoup all estimated direct and indirect
costs of administering this Article, and such fees shall be reviewed and approved on a periodic
basis by the Durham City Council.
(i) Severability. If any portion of this Article is determined to be invalid by a court of
competent jurisdiction, such determination shall not affect or invalidate the remaining portions of
this Article.
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Sec. 70-738. Peak runoff control requirements.
(a) -Purpose. The purpose of this seetieftSection 70-738 is to ensure that the increases in
volume, velocity, and peak flow of stormwater discharges from Development are addressed, in
order to mitigate the impacts on downstream properties and receiving waters. All Development,
including Development that may be exempt from pollutant reduction requirements set forth in
remaining sections of this Article, is subject to the requirements of this section unless exempted
in (b) below.
(b) Applicability;�'^fienCalculation of Prior Impervious Surface
Area. This Subsection 70-738 applies to the following Development, assessed in comparison to
pre -development prior impe vi-eti&Impervious Surface conditions as defined in (1) and (2) below:
(i) relocation of existing iImpervious Surface area on a Multifamily and Other lot; (ii)
increase in iImpervious Surface area on any lot subject to limitations on
. . . iImpervious Surface area in an approved plat or plan for reasons such as watershed
protection or stormwater control measure requirements; (iii) increase of more than 2-W500
square feet in impe viett&Impervious Surface area on a Multifamily and Other lot; (iv) increase
of more than 2000 square feet of impe vietF,Impervious Surface area on a Limited
Residentialsingle family o plex residential lot included on a preliminary or final plat
submitted for review, or on any lot utilized for recreation. For purposes of calculating these
thresholds, subject Development that is part of a Common Plan of Development shall be
assessed with other portions of such common plan that have not previously complied with peak
flow requirements.
(1) For purposes of applying peak flow requirements for the 2_ and 10-year storms, the
land cover (including type and location) existing as of April 23, 1997 shall be considered the
"pre -development conditions";
(2) For purposes of applying the peak flow requirement for the 1-_-year storm, the land
cover (including type and location) that existed as of March 9, 2001 for land in the Falls
Basin and Lower Neuse Basin, and as of March 17, 2009 for land in the Jordan Basin shall
be considered the "pre -development conditions";
(c) Requirements.
(1) Stormwater impact analysis. Development that is not exempt under (b) above shall
submit a Stet t 4et: hnpaet nalysis alysis or approved alternative to
such analysis that complies with City Stormwater Standards as part of the application for
site plan or subdivision plat approval, or if such is not required, as part of submittals for
construction drawings or utility permit approval. Calculations shall be made in
conformance with City Stormwater Standards. No subdivision plats, site plans, utility
permits, or construction drawings shall be approved in the absence of a determination by the
Stefm atef T'ivisi^„Department that required submissions have been made and approved.
(2) One-year storm. Development that increases the peak runoff rate from the 1-year
storm from pre -development conditions shall provide stormwater management facilities in
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accordance with City Stormwater Standards such that there is no net increase in peak runoff
rate. This requirement shall be applicable in the Jordan basin only when one acre or more of
land has been cumulatively disturbed and the previously pervious portion of the property as
of March 17, 2009 will be developed to exceed 24% Impervious Surface area.
(3) Two_ and ten year storms. Development that increases the peak runoff rate from
either the 2-year or the 10-year storm from „Fedeve'e„me„*pre-development conditions may
be required to provide stormwater management facilities to address the impact, as
determined in accordance with City Stormwater Standards.
(4) Other design storms. Development that increases the peak runoff from other design
storms such as the 100-year storm may be required to install stormwater management
facilities to address the impact, as determined in accordance with City Stormwater
Standards.

Sec. 70-739. Stormwater Pollutant standards; exemptions.
Sections 70-739 through 70-741 set forth requirements for Stormwater Pollutants, which
include nitrogen, phosphorus, total suspended solids; (TSS), and bacteria. All Development shall
comply with these standards unless exempted as set forth in this subsection 70-739.
(a) -Exemptions for 'unit--'-&'°4�Limited Disturbances. Development in which Land
Disturbance, calculated cumulatively as of the Applicable Baseline Date, is less than the
thresholds in Table 1 below is exempt from the standards in subsections 70-740 and 70-741,
subject to paragraphs (1) and (2) below.
TABLE I- THRESHOLDS FOR APPLICATION OF STORMWATER
POLLUTANT REQUIREMENTS
Project Location
Land Disturbance
Limited Residential
I Multifamily and Other
Jordan Basin
I acre
9-51 acre
Falls Basin
0.5 acre
12,000 sq. ft.
Lower Neuse Basin
I acre
0.5 acre
(1) Common Plan of Development. Development that is part of a Common Plan of
Development shall be included in the calculation. If the applicable threshold set forth in
Table 1 is exceeded, all other portions of the Common Plan are subject to the requirements
of this Article, unless exempted by the following, the lot(s) within the Common Plan was
lawfully constructed after the baseline date in accordance with the applicable requirements
in effect at the time, ii the lot(s) had a different applicant at the time of development, and
iii) the lot(s) has a different owner(s)_ parent_ subsidiary or other affiliate than does the
project area.
(2) Redevelopment and Existing Development; maintenance of treatment.
Redevelopment and Existing Development that are exempt under these thresholds must
continue to maintain and reconstruct all SCMs in compliance with approved plans, prior
ordinance requirements, and City Stormwater Standards.
(b) Other e e Wens&LTptions. Additionally, Development is exempt if:
A. i�
1 It qualifies in its entirety as Existing Development; or
B. it is',.eate,a i the r',.w,,*,.w n Fe .,,,,a 2 It does not increase
Impervious Surface area over the Applicable Baseline Date; or
�—ii 3 It is undertaken by a state or federal entity. err . Review and appFe v4
by the state .,, tst be ,ao.,,,,,,s4.4ed); in the Falls or
D. it is a coy 4.,n eet i the Jordan basifi. -Basin, or
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(4) It is undertaken by an entity covered by its own individual National Pollutant
Discharge Elimination System (NPDES.) Municipal Separate Storm Sewer System (MS4)
permit.
Sec. 70-740. Required reductions for nutrients and TSS; alternatives; calculations_
(a)- Nutrient Loading Rate Limits. Development not exempt under subsection 70-739 shall
construct and implement SCMs so as to limit the post construction loading rate of nitrogen -and
phosphorus from the project area to the limits set forth in Table 2 below, or shall -comply with an
allowed alternative as set �9F n in (b) * below. A portion of the reduction requirements
for nitrogen and phosphorus may be met through off site measures or payments as set forth in
70-741.
TABLE 2 NUTRIENT EXPORT LOADING RATE LINHTS
Pro] ect Location
Export Limit lbs/acre/year
Nitrogen
Phosphorus
r,,�
2-.2
8,92
Falls Basin
2.2
0.33
Lower Neuse Basin
3.6
not required
N P
&*daft
-34�%
5%
F444
40%
-3-0%
N�_A
- - --.- -- . - M.-a'
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. Low Impact Developmente
Falls Basin. Development will be considered compliant with the nutrient reduction obligations
of this Section 70-740 if:
(1) In the Falls Basin it demonstrates that it meets the post development hydrologic
criteria set forth in Chapter 2 of the North Carolina Low Impact Development Guidebook
dated June of 2009, as it may be amended from time to time—; or
(e(2) hh any basin it demonstrates compliance with pre -development runoff volume
matching criteria using NC DEQ's Storm-EZ spreadsheet.
fc) TSS Reduction. TSS reduction is applicable to
Development ° in the Falls of jefdan Basins,
of 241% in the bowerNetise Basin,Tex zegeiied-as further described in this
subsection (e)-.—c) when the following conditions are met:
• An increase in Impervious Surface area occurs as compared to what existed as of
March 17, 2009, and
• The increase in Impervious Surface area assessed in comparison to pervious area
existing as of March 17. 2009 exceeds 24%.
All :,,,ro,.:.,,� �wfaeesincreased Impervious Surfaces, as reasonably practical, must drain to an
allowed SCM that is designed to provide a minimum of -85% TSS removal or designated as a
Primary SCM in the North Carolina Stormwater Control Measure Credit Document and is sized
to capture runoff from the first 1 inch of rainfall from all surfaces that drain to the SCM. These
requirements are expanded, and/or modified as follows:
-(I) Piped areas in Lois, Pensity, PFejeets.low densiU projects. Projects that do
not require construction of SCMs because their iemeiImpervious Surface percentage is
less than that described in the paragraph above must treat TSS from stormwater runoff that
is conveyed in non -vegetated conveyances, such as stormwater pipes, but excluding road
and driveway crossings.
(2) Overtreatment to address untreatable areas. Where treatment for TSS is not
reasonably practicable; as determined by the Department, such as when
. . ietisImpervious Surface areas include offsite transportation improvements or small
noncontiguous areas at the edge of a project, additional reductions of TSS may be required
in treatable areas, such as overtreatment in other project areas or treatment of off -site Pa r.
off -site run-on.
(i
Calculations for Nutrient Loading and TSS Removal. Pollutant loading calculations shall
be made using City Stormwater Standards. -All increases in :ro,�.: ,,,� �uffaeeaImpervious
Surfaces shall be included, including but not limited to internal and off siteoffsite transportation
improvements- in City maintained right-of-way. Approved methodologies for calculating
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pollutant loading she4will be maintained in writing by the Public Works Department, and
she4will include those methodologies and calculations required to be used by the Divisi
Wafer Qtia4tyhy NC DEQ or DWQ apff&ved aftem tealternative methodologies approved by
the Public Works Department and NC DEQ.
(g}e Submittals. An applicant shall submit pollutant loading calculations for the pre- and
post -development conditions in accordance with City Stormwater Standards as part of its
application and as part of the stormwater impact analysis for approval of a subdivision or site
plan, utility permit, or construction drawings for a street or utility.
Sec. 70-741_ On -site treatment requirements; offsite purchase and credit options;
bacteria control.
(a) -On Site Nutrient Treatment Requirements. Nitrogen
and phosphorus reduction requirements may be met, in part, through offsite management
measures or the purchase of nutrient credits. -At a minimum, however, in the Te�Falls
BasinsBasin a percentage of the required nitrogen and phosphorus reductions must be achieved
through onsite treatment, in the amount shown in Table 43 below. In addition to meeting the
percentage reductions below, in the jefda-n a*d Lower Neuse BasiffsBasin, nitrogen export load
from the site must not exceed -6 lbs. per acre per year for Limited Residential, and 10 lbs_ per
acre per year for Multifamily and Other. (Note: offsite credit purchases do not meet TSS
removal requirements, which must be met onsite.)
TABLE 43 ONSITE NUTRIENT TREATMENT REQUIREMENTS
Minimum Onsite Nutrient Treatment
Project Location
Nitrogen
Phosphorus
r�raaiaii
a - GE1�E'�iir
*nnot fr-eqair-ed
*nnot f,- -e
a .ie
gii
fedw4ieff
*50% of
*50% of
Falls - General
required reduction
required reduction
Falls and jerda
*30% of
*30% of
:,Downtown
required reduction
required reduction
Area
Falls a4 a
exceeding thresholds
*30% of
*30% of
but with less than 1
required reduction
required reduction
acre land disturbance
No Percentage
No Pefeeff+ate
,-o,�,,,.+;EMS ,�„+
d b
reductions apply, but
a_�,:,
o ,,, �ppl
Lower Neuse
the 6/10 nitrogen
`rogen
�, limit deseribe
ei4
export limit described
in paragraph (a)
i. fn ap
above must be met
Most ,s not
required
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*The "required reduction" is the difference between the post --development loading rate
in pounds per acre per year multiplied by the site fro& ;r aeFes before treatment minus the
loading rate target, in pounds per acre per year multiplied by the afros _ The percentage
shown in the chart above is applied to fithe difference and the resulting number is the
amount in pounds/acre/year e€that the nutrient ,-o,auetio tha loading rate must be
aehie,vereduced onsite.
-(b) -Offset Payments to .State Approved Nutrient
Mitigation Banks. Development and Redevelopment shall have the option of purchasing nutrient
credits from state -approved nutrient banks to partially offset nitrogen and/or phosphorus loads as
allowed by State law and regulation, including but not limited to 15A NCAC 02B.0235, 15A
NCAC 02B.0282, and 15A NCAC 02B.0240, as they may be amended from time to time. In
. The
number of pounds for which credits are purchased shall be increased by 5% if the nutrient bank
is not located in the City of Durham. The following additional requirements shall apply:
(1) Location ofnutrient banks. Development in the Falls Basin must use nutrient
banks located in the upper Falls portion of the Falls Basin — the portion that is north and/or
west of Highway 50.
2,f2LCertifzcation of Nutrient Bank Provider. Offset credits may only be obtained
from nutrient banks certified by the state.
(3) Utilization of NCDEO Division ofMitiyation Services (formerly known as
Ecosystem Enhancement Program..-). Credits may also be obtained from the NC EEesystefn
Erhaneement PfE)gf mDivision of Mitigation Services if such credits are available, and if
applicable state requirements regarding utilization of private nutrient banks are first met.
4-ahCertifzcation ofcredits. Credits purchased pursuant to this subsection (b) shall be
verified by the State and proof of such verification that meets City requirements shall be
presented prior to approval of a final plat, or if no plat is required, prior to issuance of the
first building permit within the project, or such earlier deadline as may be required by City
Stormwater Standards.
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Lem
}Bacteria ^'; eon"! of et ^,r identogedBemoval; Control of Other Identified
Stormwater Pollutants. All Development which constructs StoFmw4ef Gen4e! Measwe^SCMs
in order to comply with this Article and which is located in an area that is subject to a state —
approved Total Maximum Daily Load for bacteria shall be required to have at least one np •mart'
SCM for each stormwater discharge that is rated as medium —good high, or excellent for its
ability to remove bacteria from stormwater. Ratings shall be those that appear in the nest
tutilized version of the "TC44EN-RNC DEQ Stormwater design manual and/or North
Carolina Stormwater SGN4 m.,,,,,.,' Control Measure Credit Document as specified in the
Reference Guide for Development or as determined or approved by the Director. In addition,
SCMs required to be constructed under this Article must also treat any other pollutant for which
a Total Maximum Daily Load has been identified for the area within which the SCM is located.
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Sec. 70-742. Design, construction, and completion of SCMs and stormwater
conveyances.
The owner(s) and/or the developer(s) of any Development for which SCMs and/or
Stormwater Conveyances have been approved, and persons or entities that have contracted to
perform all or a part of an owner's or developer's obligations, shall be responsible for complying
with the requirements set forth below.
(a)— Design. Stormwater Facilities required by this Article shall be designed in accordance
with City Stormwater Standards. Dams, as defined by the North Carolina Dam Safety Law,
including but not limited to NCGS 143-215.23 et seq., and associated state administrative codes,
as they may be amended in the future, are subject to the above -cited state requirements.
Sten:nwater- Faeilit4es that afe 00t Fe"iFed by this Aftiele shall be s*eet to applieable City
—(b) Approvals for Stormwater Facilities. Stormwater Facilities required tm4ffby this
Article or any other requirement of City Code orb the Unified Development Ordinance shall be
constructed in accordance with City Stormwater Standards. Plans for such ..,E)fk ard aBy ether
,Stormwater Facilities shall be
submitted to the Department for review and approval on such timetable as required in City
Stormwater Standards. City Stormwater Standards may require that permits be obtained for such
work.
(c) -Constructions, fees, tnainte to i,.,,,,eial RuFanleesPlans. Fees. Financial
Guarantees. For a Development in which construction of one or more Stormwater Control
Measures is required, the owner(s) and/or developer(s) must ensure compliance with (1) through
(5) below prior to one of the following: i) recordation of final plat for
development involving individual ownership intefes lots or-anl9tunits within the
development; ii) issuance of a utility permit for development which is not exclusively
residential home/condominium ownership, iii) issuance of a building permit for construction
within 41+ea development; ' which is not exclusively for residential
home/condominium ownership and does not require a utility permit f the development; ate; or
iv) construction drawing approval for any infrastructure within the development: which will not
require a building or utility permit.
(1) Review and approval of the ;stormwater impact
anal
(2) Review and approval of plans and specifications for the SCMs and
Stormwater Conveyances within the development;
(3)_ Payment of permit and review fees required by the Department;
(4) In the case of development involving individual ownership of
lots or units within the development, creation of an owners' association prior to recordation
of an .,gfeement are 10r covenants that meetboth comply with City Stormwater Standards
15

and that —provide, among other things, for the eenst.-,,etior are long term maintenance,
inspection, repair, and reconstruction of the SCMs in accordance with City Standards
be a meets to stteh agreement-,—;.
(5) Provision of financial guarantees to ensure the long -_term maintenance,
inspection, repair, and reconstruction of stormwater control measures in accordance with
City Code Section 70-751, the Unified Development Ordinance, and City Stormwater
Standards.
(d) -Completion of ons�Construction. Construction of SCMs and stormwater
conveyances -shall be completed -prior to final d as built drawings submitted to
plat approval, if a final plat approval is required for the City, in aeeefdanee with..
development. For a building„ structure, or use
not deemed single family or duplex residential development, construction of SCMs and
stormwater conveyances shall be completed prior to issuance of a certificate of occupancy unless
a -performance guarantee to ensure -completion is approved pursuant to (e) below.
(e)- Performance Guarantees. The owner or developer of a Development in which the
requirements of (d) above have not been completed shall provide a performance guarantee of a
type as set forth in City Stormwater Standards. The amount provided shall be as set forth in
City Stormwater Standards, or as determined by the Director, which shall at a minimum require
that all direct and indirect costs of completion and compliance with City requirements be
guaranteed. City Stormwater Standards shall also include deadlines for completion of facilities
for which performance guarantees have been provided. Deadlines may be modified by the
Director to better ensure the protection of the City and the public, or to address special
circumstances. n pef f,,-.,,. nee n ntee pfevided , , def this subseetio,, may be used for- any
(f)- Conditional Certificates; Reduction of Guarantees. -The City is authorized to issue
conditional certificates of compliance for buildings for which erformance guarantees
have been provided and completion has been ensured consistent with City Stormwater Standards.
In addition, City Stormwater Standards may allow for reduction of performance guarantees as
approved by the Department as Stormwater Facilities are completed and requirements are met.
(g) -Obligation to Complete Facilities; City Use ofLand. The
owner of property for which a stormwater facility has been approved as part of a Development,
and any parties that have obligated themselves to construct such facilities under approved plans,
permits, or previously approved agreements, are legally obligated to construct the facilities
approved, or to pay for the construction of such facilities, if any land disturbing activity has
occurred in the Development. An owner that applies for and receives approval to construct a
stormwater facility in a Development agrees, ,
the Development that me -.. � e., e 1 by sunh ­VneF, and to all peFSORS OF entities that titilize an
16

. that the
City and its agents are authorized to enter upon the property and to construct the stormwater
facilities if the owner fails to do so. This provision does not: i) require the City to take any
action, acquire any property, or construct any facility; or ii) create any right or entitlement for
any persons or entities other than the City; or iii) limit the City's ability to require other persons
or entities not identified in this subsection (g) to construct stormwater facilities that have not
been constructed; or iv) limit the City's ability to utilize any other authority it may have under
law to recoup the cost of construction of stormwater facilities, including but not limited to
authority to assess properties served by such facilities.
(h) Rights ,•,,.der ^ogntru^'sUnder Contracts. The City is entitled to enforce any third party
rights for the benefit of the public or itself that may be expressly or implicitly created in
contracts for the design and construction of SCMs or Stormwater Conveyances. Contractors
that have not performed in accordance with such contracts may be considered responsible parties
under this Article.
17

Sec. 70-743. Inspection, Maintenance, Repair, and Reconstruction.
(a) -Private maintenance Fespensib;';o, Maintenance Responsibility. The inspection,
maintenance, repair and reconstruction of Stormwater Control Measures and Stormwater
Conveyances not Wealed i -Y Fight ,.fway shall be the responsibility of i) the owners of the
property on which such SCMs and conveyances are located; and, ii) any person(s) or entity that
basis legally .,gFee,a to be responsible f r the SGN4 ; pursuant to applicable agreements and/or
covenants, and -iii) the downer s of properties served by the SCMs or conveyances, as
determined by reference to site plans, plats, and construction drawings for the SCMs--eF
(b) Level of into,., ne-eMaintenance. Every SCM and Stormwater
ConveyaneesConveyance shall be maintained, repaired, and reconstructed so as to continue its
functionality to the level for which it was designed for the control and/or conveyance of
stormwater and for the treatment of Stormwater Pollutants. Maintenance, repair, and
reconstruction shall be performed in compliance with City Stormwater Standards. Standards for
maintenance include but are not limited to the speeie-most recently pproved version of the
operation and maintenance manual specifically prepared for each facility, a recorded stormwater
facility agreement
Dot, and- the most recent version of the "Owner's Maintenance Guide for Stormwater
SCMs Constructed in the City of Durham."
(c) Annual pirivate . Private Inspection. An annual inspection shall be conducted
by an SCM Maintenance Certifier and a report that meets City Stormwater Standards shall be
ptzevi submitted to the Director for each Stormwater Control Measure by the persons or
entities responsible for such facility, identified in (a) above. The report shall be submitted on
such schedule as assigned by the Department. In addition, such persons or entities shall
maintain inspection and repair reports regarding the SCMs as required by City Stormwater
Standards.
(d) -City 4g4tftht to pee�Inspect• The City may inspect Stormwater Control Measures
and Stormwater Conveyances located on private property. Inspection may include but is not
limited to testing of structures, water, or vegetation as the City determines may be useful to
determine the history or performance of the SCM or conveyance.
Sec. 70-744. Remedies for Violation.
The following are considered a violation of this Article: noncompliance with any
requirement of this Article or prior stormwater ordinances; noncompliance with City Stormwater
Standards implementing this Article; and noncompliance with any approval, permit, or similar
authorization granted pursuant to this Article. A violation of this Article is a violation of the City
Code and is subject to all civil and criminal penalties allowed under law, in addition to those
specifically set forth below. Persons and entities identified in Sec. 70-742 and 70-743(a) as
responsible for compliance with this Article shall be responsible for any violation. Remedies are
cumulative, and may be exercised separately, together, or in any order.
:.

(a)- Withholding of Permits, Approvals, and Certificates of Occupancy/Compliance. In the
event of violation of this Article, the City may withhold any approval or permit for any
development activity occurring on the property or in the development where the violation exists,
including but not limited to withholding any permit or certificate of occupancy/compliance for
any structure served by an actual or proposed SCM or stormwater conveyance that is in
violation.
(b) -Stop i-etk eFdeirWork Order. The City may issue a stop work order to any person or
entity performing work on property and/or in a development where there is a violation of this
Article.
-(c) —Injunction; Nuisance; Costs as Lien.- The City may institute an action in a court of
competent jurisdiction for an injunction, order of abatement, or any other equitable remedy not
prohibited by law to remediate a violation of this Article. The City may also maintain an action
under GS 160A-193 to remedy a condition prejudicial to the public health and safety. Costs of
correction sustained by the City may be assessed as a lien against property, as allowed by law.
(d)- Incorporation of 70-538 et seq. In addition, all remedies and procedures set forth in
Sections 70-538 through 70-542 of the City Code shall apply to violations of this Article whether
or not such violations are also violations of City Code Section 70, Article V.
SECTION 2. This Ordinance shall be effective Ttt'�12on the date of adoption and
shall replace the above -cited sections of the City Code.
W