HomeMy WebLinkAboutSW8050313_CURRENT PERMIT_20050506STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT
NO.
SW �SUJD�Jl3
DOC TYPECURRENT
PERMIT
APPROVED PLANS
❑ HISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
�lv�SZZS�P
YYYYMMDD
k
fw; W A rFMichael F. Easley, Governor
RQ
�0 G William G. Ross, Jr., Secretary
North Carolina Deparkment of Environment and Natural Resources
Alan W. Klimek, P.E. Director
Division of Water Quality
May 6, 2005 _
Mr. Earl Worsley, Member Manager
Worsley Investment and Development Co., LLC
P.O. Box.490
Wrightsville Beach, NC 28480
Subject: Stormwater Permit No. SW8 050313
Preservation Park
High Density Project
New Hanover County
Dear Mr. Worsley:
O6/OS P—/6
The Wilmington Regional Office received a complete Stormwater Management Permit
Application for Preservation Park on May 5, 2005. Staff review of the plans and specifications
has determined that the project, as proposed, will comply with the Stormwater Regulations set
forth in Title 15A NCAC 2H.1000. We are forwarding Permit No. SW8 050313 dated May 6,
2005, for the construction of the subject project.
This permit shall be: effective from the date of issuance until May 6, 2015, and shall be subject
to the conditions and limitations as specified therein. Please pay special attention to the
Operation and Maintenance requirements in this permit. Failure to establish an adequate
system for operation and maintenance of the stormwater management system will result in
future compliance problems.
If any parts, requirements, or limitations contained in this permit are unacceptable, you have
the right to request an adjudicatory hearing upon written request within thirty (30) days
following receipt of this permit. This request must be in the form of a written petition,
conforming to Chapter 150B of the North Carolina General Statutes, and filed with the Office of
Administrative Hearings, P.O. Drawer 27447, Raleigh, NC 27611-7447. Unless such demands
are made this permit shall be final and binding.
If you have any questions, or need additional information concerning this matter, please
contact Paul Bartlett, or me at (910) 395-3900.
Sin ereiy,
Ed Beck
Acting Regional Supervisor
Surface Water Protection Section
ENBlptb: S:1WQSISTORMWATERIPERMIT1050313
CC' Phillip G. Tripp, P.E., Tripp Engineering, P.C.
Tony Roberts, New Hanover County Building Inspections
City of Wilmington Stormwater Services
Beth E. Wetherill, New Hanover County Engineering
Division of Coastal Management
Paul T. Bartlett, P.E.
Wilmington Regional Office
Central Files
North Carolina Division of Water Quality 127 Cardinal Drive Extension Phone (910) 395-3900 Customer Service 1-877-623-6748
Wilmington Regional Office Wilmington, NC 28405-3845 FAX (919} 733-2495 Internet, h2o encstate.nc us One
NorthCarolina
An Equal Opportunity/Affirmative Action Employer— 50% Recycied110% Post Consumer Paper Natundy
State Stormwater Management Systems
Permit No. SW8 050313
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
STATE STORMWATER MANAGEMENT PERMIT
HIGH DENSITY DEVELOPMENT
.j
In accordance with the provisions of Article 21 of Chapter 143, General Statutes of
North Carolina as amended, and other applicable Laws, Rules, and Regulations
PERMISSION IS HEREBY GRANTED TO
Earl Worsley and Worsley Investment and Development Co., Inc.
Preservation Park
New Hanover County
FOR THE
construction, operation and maintenance of two, connected, extended detention
stormwater wetlands in compliance with the provisions of 15A NCAC 2H .1000
(hereafter referred to as the "stormwater rules') and the approved stormwater
management plans and specifications and other supporting data as attached and on file
with and approved by the Division of Water Quality and considered a part of this permit.
This permit shall! be effective from the date of issuance until May 6, 2015, and shall be
subject to the following specified conditions and limitations:
I. DESIGN STANDARDS
1. This permit is effective only with respect to the nature and volume of stormwater
described'in the application and other supporting data.
2. This stormwater system has been approved for the management of stormwater
runoff as described in Section 1.6 on page 3 of this permit. The stormwater
control has been designed to handle the runoff from 18,580 square feet of
impervious area.
3. The tract will be limited to the amount of built -upon area indicated on page 3 of
this permit; and per approved plans.
4. All stormwater collection and treatment systems must be located in either
dedicated'`common areas or recorded easements. The final plats for the project
will be recorded showing all such required easements, in accordance with the
approved -plans.
5. The runoff,from all built -upon area within the permitted drainage area of this
project must be directed into the permitted stormwater control system.
Page 2 of 8
6.
State Stormwater Management Systems
Permit No. SW8 050313
The following design criteria have been provided in the extended detention
stormwater wetlands and must be maintained at design conditions:
a. Drainage Area, Acres: 0.95
- Onsite, .ft -41,382
-
Offsite, ft2: none
b. Total Impervious Surfaces, ft2: 18,580
C. Design Storm, inches-, 1.0
d. Pond Depth, feet: 3.0
e. TSS removal efficiency: 85%
f. Permanent Pool
(1) Elevation, FMSI : 22.0
(2 Surface Area, ft : 1,646
(3 70% of surface area as marsh, depth 0" to 18"
(4 Equal distribution of surface area (35% & 35%) between 0"-9" and
9"-18..
(5)' ` 15% of surface area as small pool at outlet location to prevent
sediment from interfering with outlet structure functions
(6) Plantings within normal, permanent pool in accordance with the
approved Vegetation Planting Plan.
g. Permitted Storage Volume, ft3: 1,770
h. Temporary Storage Elevation, FMSL: 23.0
i. Controlling Orifice: 0.5" 0 pipe
j. Permitted Forebay Volume, ft3: 391
k. Vegetation Planting: In accordance with the approved Vegetation
Planting Plan (attached).
I. Wetland Stabilization: Within 14 days of construction, either in the form
of final vegetation or a temporary means until the vegetation becomes
established.
M. Receiving Stream/River Basin: Bradley Creek 1 Cape Fear
n. Stream Index Number- 18-87-24-4-(1)
o. Classification of Water Body: "Sc"
II. SCHEDULE OF COMPLIANCE
1. The stormwater management system shall be constructed in its entirety,
vegetated -and operational for its intended use prior to the construction of any
built -upon surface.
2. During construction, erosion shall be kept to a minimum and any eroded areas of
the system will be repaired immediately.
Page 3 of 8
State Stormwater Management Systems
Permit No. SW8 050313
3. The permittee shall at all times provide the operation and maintenance
necessary to assure the permitted stormwater system functions at optimum
efficiency. The approved Operation and Maintenance Plan must be followed in
its-entirety.and maintenance must occur at the scheduled: intervals including,.but- _
not limited to:
a. Semiannual scheduled inspections (every 6 months).
b. Sediment removal.
C. Mowing and revegetation of slopes and the vegetated filter.
d. Immediate repair of eroded areas.
e. Maintenance of all slopes in accordance with approved plans and
specifications.
f. Debris removal and unclogging of outlet structure, orifice device, flow
spreader, catch basins and piping.
g. Access to the outlet structure must be available at all times.
4. Records of maintenance activities must be kept and made available upon
request to authorized personnel of DWQ. The records will indicate the date,
activity, name of person performing the work and what actions were taken.
5. The facilities shall be constructed as shown on the approved plans. This permit
shall become voidable unless the facilities are constructed in accordance with
the conditions of this permit, the approved plans and specifications, and other
supporting data.
6. Upon completion of construction, prior to issuance of a Certificate of Occupancy,
and prior to operation of this permitted facility, a certification must be received
from an appropriate designer for the system installed certifying that the permitted
facility has been installed in accordance with this permit, the approved plans and
specifications, and other supporting documentation. Any deviations from the
approved plans and specifications must be noted on the Certification. A
modification may be required for those deviations.
7. If the stormwater system was used as an Erosion Control device, it must be
restored to design condition prior to operation as a stormwater treatment device,
and prior to occupancy of the facility.
8. Access to: the stormwater facilities shall be maintained via appropriate
easements at all times.
9. The permittee shall submit to the Director and shall have received approval for
revised plans, specifications, and calculations prior to construction, for any
modification to the approved plans, including, but not limited to, those listed
below:
a. Any revision to any item shown on the approved plans, including the
stormwater management measures, built -upon area, details, etc.
b. Project name change.
C. Transfer of ownership.
d. Redesign or addition to the approved amount of built -upon area or to the
drainage area.
e. Further subdivision, acquisition, lease or sale of all or part of the project
area. The project area is defined as all property owned by the permittee,
for'which Sedimentation and Erosion Control Plan approval or a CAMA
Major permit was sought.
f. Filling in, altering, or piping of any vegetative conveyance shown on the
approved plan.
Page 4 of 8
State Stormwater Management Systems
Permit No. SW8 050313
10. The permittee shall submit final site layout and grading plans for any permitted
--future.areas shown on the approved plans, prior to construction: -- -m & .- -
11. A copy of the approved plans and specifications shall be maintained on file by
the Permittee for a minimum of ten years from the date of the completion of
construction.
12. The Director may notify the permittee when the permitted site does not meet one
or more of the minimum requirements of the permit. Within the time frame
specified in the notice, the permittee shall submit a written time schedule to the
Director for modifying the site to meet minimum requirements. The permittee
shall provide copies of revised plans and certification in writing to the Director
that the changes have been made.
III. GENERAL CONDITIONS
This permit is not transferable except after notice to and approval by the Director.
In the event of a change of ownership, or a name change, the permittee must
submit a formal permit transfer request to the Division of Water Quality,
accompanied by a completed name/ownership change form documentation
from the parties involved, and other supporting materials as may be appropriate.
The approval of this request will be considered on its merits and may or may not
be approved. The permittee is responsible for compliance with all permit
conditions until such time as the Division approves the transfer request.
2. Failure to abide by the conditions and limitations contained in this permit may
subject the Permittee to enforcement action by the Division of Water Quality, in
accordance with North Carolina General Statute 143-215.6A to 143-215.6C.
3. The issuance of this permit does not preclude the Permittee from complying with
any and all statutes, rules, regulations, or ordinances, which may be imposed by
other government agencies (local, state, and federal) having jurisdiction.
4. In the event that the facilities fail to perform satisfactorily, including the creation
of nuisance conditions, the Permittee shall take immediate corrective action,
including those as may be required by this Division, such as the construction of
additional or replacement stormwater management systems.
5. The permittee grants DENR Staff permission to enter the property during normal
business hours for the purpose of inspecting all components of the permitted
stormwater management facility.
6. The permit may be modified, revoked and reissued or terminated for cause. The
filing of a request for a permit modification, revocation and reissuance or
termination does not stay any permit condition.
7. Unless specified elsewhere, permanent seeding requirements for the stormwater
control must follow the guidelines established in the North Carolina Erosion and
Sediment Control Planning and Design Manual.
8. Approved.,#ans and specifications for this project are incorporated by reference
and are enforceable parts of the permit.
Page 5 of 8
State Stormwater Management Systems
Permit No. SW8 050313
9. The permittee shall notify the Division any name, ownership or mailing address
changes within 30 days.
Permit issued this the-6th day -of May-2005::
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
-pp--
Alan W. Klimek, P.E., Director
Division of Water Quality
By Authority of the Environmental Management Commission
Page 6 of 8
State Stormwater Management Systems
Permit No. SW8 050313
Preservation Park
Stormwater Permit No. SW8 050313
New Hanover County
Designer's Certification
I, , as a duly registered
in the State of North Carolina, having been authorized to observe (periodically/ weekly/
full time) the construction of the project,
(Project)
for (Project Owner) hereby state that, to the
best of my abilities, due care and diligence was used in the observation of the project
construction such that the construction was observed to be built within substantial
compliance and intent of the approved plans and specifications.
The checklist of items on page 2 of this form is included in the Certification.
Noted deviations from approved plans and specification -
Signature
Registration Number
Date
SEAL
Page 7of8
State Stormwater Management Systems
Permit No. SW8 050313
Certification Requirements:
r -1: . --The drainage area to the system contains approximately_the permitted - .- -
acreage.
2. The drainage area to the system contains no more than the permitted
amount of built -upon area.
3. All the built -upon area associated with the project is graded such that the
runoff drains to the system.
4, All roof drains are located such that the runoff is directed into the system.
5. The outlet/bypass structure elevations are per the approved plan.
.6. The outlet structure is located per the approved plans.
7. Trash rack is provided on the outlet/bypass structure.
8. All slopes are grassed with permanent vegetation.
.9. Vegetated slopes are no steeper than 3:1.
.10. The inlets are located per the approved plans and do not cause short-
circuiting of the system.
.11. The permitted amounts of surface area and/or volume have been
provided.
.12. Required drawdown devices are correctly sized per the approved plans.
.13. All required design depths are provided.
14. All ,required parts of the system are provided, such as a vegetated shelf,
and a forebay.
15. The required system dimensions are provided per the approved plans.
cc: NCDENR-DWQ Regional Office
Tony Roberts, New Hanover County Building Inspections
PREISERVATION PARK
PLANTING PLAN
Prepared for:
Worsicy Investment and Development Co., 1-1-C
Wrightsvillc Beach, NC
Prepared by:
Land Management Grotip., Inc.
Wilmington, NC
c
MIRY 0
13y-
�%,Iarch 2005
- -PLANT MA AERIAL
.Areas to be planted include a zone of upper marsh (bottom elevation 22.0' to
21.25') and a zone of lower marsh (bottom elevation 21.25' to 20.5') (figure 1). A zone
labeled as `pool' will not be planted. Only herbaceous species will be planted. The
selection of plant species is based on Soil moisture, diversity, and hardiness (Tables I and
2). In addition, native species known to thrive in the coastal plain have been chosen.
Material in each zone xvill be planted on a 2' spacing, in a random fashion to ensure. a
good mix of species throughout each zone. All material to be planted will be plugs and
will be installed between acceptable planting %vindo�vs (N-larch 15 through Jule 30 or
September 15 through November 15). Plants will be provided by Mellon! Marsh Farm;
located in Siler Citv, NC.
Table 1. Herbaceous species to be planted within the upper marsh area (irregular to
regular inundation) at the Preservation Park constructed wetland. Material to be planted
at a 2' spacing.
11 Common Name Scientific Name
Soft rush
Juncus effusus
fringed sedge
Carex crinita
Switchgrass
pwlicunz vetgaluna
Broomsedgc
Andropogon virgirzicus
`fable 2. Herbaceous species to be planted WIL1lin the lower marsh area (regular to
permanent inundation) at the Preservation Park constructed Nirctland. Nlaterial to be
planted at a 2' spacing.
11 Common Nance Scientific Name
Bulrush
Scirpus validus
Spike rush
Eleocharis obiuso
Pickerel weed
Pon(eclaria cordam
Arrow arum
Pellandl-a virgilaica
0
-_ 4
ii: i�,- r:Mx -t^'.
?PLANTING METHODS : -
Mellow Marsh Farm will deliver the material to the site and will transport the
plants in trays. Material will be covered during transport and xill stay moist until planted.
Plugs will be Installed by staff of Land Management Group, Inc. Ms. Kim Williams of
Land Management Group, Inc. is a certified Plant Professional (NCAN) and will oversee
the planting activities. For each plant, a small vertical hole will be made using a hand
spade. Then a small amount of slow -release fertilizer will be placed at the bottom of the
hole. Finally; the plug will be installed and soil will be placed around the plug so that the
roots are surrounded by the soil. If the soil is not moist at the time of planting, the plants
will be watered immediately after installation.
.OFFICE USE ONLY:. .
Date Received
Fee Paid
Permit Number
3 11� 05
1S4DQtA2A
13
5 IJ 100)h ` Hemel "J. J'1. Z
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
This form may be photocopied for use as an original
I. GENERAL INFORMATION
1. Applicants name (specify the name of the corporation, individual, etc. who owns the project):
Worsley Investment and Development Co. LLC
2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance):
Earl Worsley, Member Manager
3. Mailing Address for person listed in item 2 above:
P.O. Box 490
City: Wrightsville Beach State: NC Lip: 28480
Telephone Number: 910-256-0044
4. Project Name (subdivision, facility, or establishment name — should be consistent with project name on
plans, specifications, letters, operation and maintenance agreements, etc.):
Preservation Park
5. Location of Project (street address):
108 Sebrell Avenue
City: Wilmington County: New Hanover
6. Directions to project (from nearest major intersection):
From the intersection of US Hwy 76 and 132, travel north 1800 If and turn right on Park Avenue. Travel
East 23 miles and turn right on Sebrell Avenue. Travel south 195 If. Site is on the right.
7. Latitude : N 340 12' 30" Longitude: W 770 50' 30" of project
8. Contact person who can answer questions about the project:
Name: Phillip TrippTelephone Number: 910-763-5100
iI. PERMIT INFORMATION:
1. Specify whether project is (check one): X_ New Renewal Modification
Form SWU-101 Version 3.99 Pagel of4
2. If this application is being submitted as the result of a renewal or modification to an existing permit, list
The existing permit number and its issue date (if known)
3. Specify the type of project (check one):
_� Low Density )� High Density Redevelop General Permit Other
4. Additional Project Requirements (check applicable blanks):
CAMA Major X Sedimentation/Erosion Control 404//401 Permit NPDES Stormwater
Information on required state permits can be obtained by contacting the Customer Service Center at
1-877-623-6748.
III. PROJECT INFORMATION
1. In the space provided below, summarize how stormwater will be treated. Also attach a detailed narrative
(one to two pages) describing stormwater management for the project.
extended detention stormwater wetland
2. Stormwater runoff from this project drains to the Cape Fear River basin.
3. Total Project Area: 3.06 acres
5. How many drainage basins does the project have? 1
4. Project Built Upon Area: 13.94 %.
6. Complete the following information for each drainage area. If there are more than two drainage areas in the
project, attach an additional sheet with the information for each area provided in the same format as below.
Basin Information
r ; Dramage Basin l -
_ Drainage�B'asin 2
Receiving Stream Name
Bradley Creek
Receiving Stream Class
C-SW
Drainage Basin Area
0.95 ac.
Existing Impervious * Area
-
Proposed Impervious * Area
0.43.ac.
% Impervious* Area (total)
45.04%
Impervious * Surface,Area
',Drainage°Basin--1
_. --
Drainage Basin 2
On -site Buildings
10,800 sf
On -site Streets
4,289 sf
On -site Parking 1 Concrete
3,491 sf
On -site Sidewalks
-
Other on -site
-
Off -site
-
Total:
E= 18,580 sf_
* Impervious area is defined as 1he built upon area including, but not limited to, buildings, roods, parking
areas sidewalks, gravel areas, etc.
Form SWU-101 Version 3.99 Page 2 of
7. Flow was the off -site impervious area listed above derived?
ITV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS
The following italicized deed restrictions and protective covenants are required to be recorded for all
subdivisions, outparcels and future development prior to the sale of any lot. If lot sizes vary significantly, a
table listing each lot number, size and the allowable built -upon area for each lot must be provided as an
attachment.
1. 7hefollowing covenants are intended to ensure ongoing compliance with state stormwater management pernut
number as issued by the Division of Water Quality. These covenants play
not be changed or deleted without the consent of the State.
2. No more than square feet of any lot shall be covered by structures of impervious materials.
Impervious materials include asphalt, gravel, concrete, brick stone, state or similar material but do not include wood
decking or the water surface of swinnning pools.
3. Swales shall not be filled in, piped or altered except as necessary to provide driveway crossings.
d. Built -upon area in excess of the permitted amount requires a state stormwater management permit modificalion prior
to construction.
.i. All permitted runofffrom oulparcels orfuture development shall be directed into the permitted stornmvaler control
systern. These connections to the stormwater control system shall be performed in a manner that maintains the
integrity and performance of the system as permitted.
By your signature below, you certify that the recorded deed restrictions and protective covenants for this project
shall include all the applicable items required above, that the covenants will be binding on all parties and
persons claiming under them, that they will run with the land, that the required covenants cannot be changed or
deleted without concurrence from the State, and that they will be recorded prior to the sale of any lot.
V. SUPPLEMENT FORMS
The applicable state stormwater management permit supplement form(s) listed below must be submitted for
each BMP specified for this project. Contact the Stormwater and General Permits Unit at (910) 733-5083 for
the status and availability of these forms.
Form SWU-102
Wet Detention Basin Supplement
Form SWU-103
Infiltration Basin Supplement
Form SWU-104
Low Density Supplement
Form SWU-105
Curb Outlet System Supplement
Form SWU-106
Off -Site System Supplement
Form SWU-107
Underground Infiltration Trench Supplement
Form SWU-108
Neuse River Basin Supplement
Form SWU-109
Innovative Best Management Practice Supplement
Form SWU-101 Version 3.99 Page 3 of 4
VI. SUBMITTAL REQUIREMENTS
Only complete application packages will be accepted and reviewed by the Division of Water Quality (DWQ).
A complete package includes all of the items listed below. The complete application package should be
submitted to the appropriate DWQ Regional Office.
I . Please indicate that you have provided the following required information by initialing in the space
provided next to each item.
Applicant's Initials
• Original and one copy of the Stormwater Management Permit Application FormL
• One copy of the applicable Supplement Form(s) for each BMP C�L
• Permit application processing fee of $420 (payable to NCDENR)
• Detailed narrative description of stormwater treatment/management_
• Two copies of plans and specifications, including: G
- Development/Project name
- Engineer and firm
- Legend
- North arrow
- Scale
- Revision number and date
- Mean high water line
Dimensioned property/project boundary
Location map with named streets or NCSR numbers
Original contours, proposed contours, spot elevations, finished floor elevations
Details of roads, drainage features, collection systems, and Stormwater control measures
Wetlands delineated, or a note on plans that none exist
Existing drainage (including off -site), drainage easements, pipe sizes, runoff calculations
- Drainage areas delineated
Vegetated buffers (where required)
VII. AGENT AUTHORIZATION
If you wish to designate authority to another individual or firm so that they may provide information on your
behalf, please complete this section.
Designated agent (individual or firm): _Tripp Engineering, P.C.
Mailing Address: 419 Chestnut Street
City: Wilmington State: NC Zip: 28401
Phone: 910 763-5100 Fax: 910 763-5631
VIII. APPLICANT'S CERTIFICATION
I, (print or type name ofperson listed in General Information, item 2) Earl Worsley
certify that the information included on this permit application form is, to the best of my knowledge, correct and
that the project will be constructed in conformance with the approved plans, that the required deed restrictions
and protective covenants will be recorded, and that the proposed project complies with the requirements of 15A
NCAC 2H .1000.
Signature: V� Date: 1K o
Form SWU-101 Version 3.99 Page 4 of
Permit No. Yee 5 0 r7 3/ 3
(to be provided by DPVQ)
State of North Carolina
Islas - V. re"
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
EXTENDED DETENTION STORMWATER WETLANDS SUPPLEMENT
1. PROJECT INFORMATION (please complete the following information):
Project Name: Preservation Park
Contact Person: Phillip TrippPhone Number: (910 )_763-5100
For projects with multiple basins, specify which basin this worksheet applies to: 1
elevations
Basin Bottom Elevation
19.0
ft.
(floor of the basin)
Permanent Pool Elevation
22.0
ft.
(elevation of the orifice)
Temporary Pool Elevation
23.0
ft.
(elevation of the discharge structure ovefflow)
areas
Permanent Pool Surface Area
1,646
sq.ft.
(water surface area at the orifice elevation)
0" to 9" Depth
572
sq.ft.
Extended Detention Zone
9" to 18" Depth _
572
sq.ft.
High Marsh Zone
18" to 36" Depth
_490
, sq.ft.
Pool Areas
0" to 36" Depth
490
sq.ft.
Micro Pool at Outlet Structure
Drainage Area to Basin
0.95
ac.
(on -sire and off -site drainage to the basin)
Impervious Area
0.43
ac.
(on -site and off -site drainage to the basin)
volumes
Permanent Pool Volume _
1,770
(volume of the basin at permanent pool)
0" to 9" Depth
215
cu.ft.
Extended Detention Zone
9" to 18" Depth
429
cu.ft.
High Marsh Zone
18" to 36" Depth
1,126
cu.ft.
Pool Areas
0" to 36" Depth
735
cu.ft.
Micro Pool at Outlet Structure
Temporary Pool Volume Designed
1,982 cu.ft.
(volume detained above the permanent pool)
Forebay Volume Designed
391
cu.ft. (volume of the forebay)
Pace 1 of 3
k
Other parameters
SA/DA I
Diameter of Orifice
Design Rainfall
Design TSS Removal
Vegetated Filter Used
Footnotes:
6 (surface area to drainage area ratio ftotn DIVQ table)
0.5 in. (2 to 5 day temporary pool draw-doiim required)
1 in. and 25 year pre/post development flow
8'�8 % (minimum 85% required)
0 (30' required
1. When using the Division SA/DA tables, the correct SA/DA ratio for permanent pool sizing should be computed based upon the
actual impervious % and permanent pool depth. Linear interpolation should be employed to determine the correct value for non-
standard table entries.
2. In the 20 coastal counties, the requirement for a vegetative filter may be waived if the wet detention basin is designed to provide
90% TSS removal. The NCDENR BMP manual provides design tables for both 95% TSS removal and 901/6TSS removal.
I.I. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best`Management Practices Manual
(N.C. Department of Environment, Flealth and Natural Resources, February 1999) and Administrative Code
Section: 15 A NCAC 21-I .1008.
Initial in the space provided to indicate the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form.. the agent may initial below. If a requirement has not been met, attach justification.
Applicants Initials
CQ[ a. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
60C b. The forebay volume is approximately equal to 20% of the total basin volume.
c. The temporary pool controls runoff from the design storm event.
C_ d. The temporary pool draws down in 2 to 5 days.
*iA e. If required, a 30-foot vegetative filter is provided at the outlet (include non -erosive flow
Lno
CCc.
C Dr.
calculations).
f. The basin length to width ratio is greater than 3:1.
g. The basin side slopes above the permanent pool are no steeper than 3:1.
h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail),
COL, i. Vegetative cover above the permanent pool elevation is specified.
zo j. A trash rack or similar device is provided for both the overflow and orifice.
C0(_ k. A recorded drainage easement is provided for each basin including access to nearest right-
of-way.
6Pt- 1. if the basin is used for sediment and erosion control during construction, clean out of the
basin is specified to be performed prior to use as a wet detention basin
e.ml in. A mechanism is specified which will drain the basin for maintenance or an emergency.
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II1. OPERATION AND MAINTENANCE AGREEMENT
for EXTENDED DETENTION STORMWATER WETLANDS
Maintenance activities shall be performed as follows:
1. 1 After every significant runoff producing rainfall event and at least monthly,
a. inspect wet detention basin system for sediment accumulation, erosion, trash accumulation, vegetated
cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.
2. E.D. wetlands will be free of debris. Debris will be cleaned as it accumulates or at least twice annually.
Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to maintain
proper functioning.
4. E.D. wetlands should be inspected annually after a rain event to insure the basin is operating as designed.
5. Outlet structures to be inspected and cleaned of clogs or checked for too rapid of release.
6. Inlets, outlets and forebays shall be checked twice annually for sediment buildup or erosion. Repairs should
be made on any discovered problem areas. Sediment shall be removed from forebays when the depth of
sediment is 8 inches higher than original elevation. The measuring device used to determine the sediment
elevation shall be such that it will give an accurate depth reading and not readily penetrate into accumulated
sediments.
7. All components of the constructed wetland system shall be maintained in good working order.
8. Banks and slopes around the wetland shall be inspected twice annually for erosion and repaired if needed.
9. Wetland plants shall be inspected yearly for survival. Dead plants shall be removed and new plants added
to maintain plant populations.
10. Areas around E.D. wetlands shall be properly grassed and mowed. Grass height shall not exceed six inches
at any time.
1 acknowledge and agree by my signature below that 1 ain responsible for the performance of the maintenance procedures listed
above. I agree to notify DWQ of any problems with the system or prior to any changes to the system or responsible party.
Print name: Earl Worsle Title: Member Manager
Address: P.O. Box 490 Wrightsville Beach NC 28408 Phone: 910-256-0044
Signature: Date:
Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and
a resident of the subdivision has been named the president.
1, Della C. Baird , a Notary Public for the State of North Carolina , County of Ponder , do hereby certify
that Earl Worsley personally appeared before me this 25 day of February,2005, and acknowledge the due
execution of thSOr 11 yi�i+ ointenance_requirements. Witness my hand and official seal,
J_%`\O�' TAR
�� Y
SEAL %4�y' PliBOG
..... • ,
My commission expires October 15, 2006�_
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