HomeMy WebLinkAboutSW7970113_CURRENT PERMIT_20070323STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
DOC TYPE
CURRENT PERMIT
APPROVED PLANS
❑ HISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
YYYYMMDD
F WqTF
Michael F. Easley, Govemoro0G
William G. Ross Jr., secretary
�
North Carolina Department of Environment and Natural Resources
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Alan W. Klimek, P.E. Director
Division of Water Quality
March 23, 2007
O.T. Enterprises, LLC
Attn.: Brantley Tillman
1648 E. North Market Drive
Raleigh, NC 27609
Subject: Permit No. SW7970115 Modification
Hatteras Island Plaza, Phase 2
High Density Stormwater Project
Dare County
Dear Mr. Tillman:
The Washington Regional Office received a completed Stormwater Application for the subject project on
January 22, 2007. 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.
SW7970115 dated March 23, 2007 to O.T. Enterprises, LLC for two wet detention ponds to serve the Hatteras Island
Plaza, Phase 2 located at 41934 NC 12 at Kinnakeet Shores, Avon, NC.
This permit shall be effective from the date of issuance until March 23, 2017 shall void Permit No.
SW7970115 dated April 10, 1997 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. The issuance of this permit does not resolve any previous violations of the stormwater rules for
construction without a permit.
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 150E of the North Carolina General Statutes,
and filed with the Office of Administrative Hearings, 6714 Mail Service Center, Raleigh, NC 2769M714. 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 Samir
Dumpor or me at (252) 946-6481.
Arely.ore''dge Regiohal Supery
isor
Surface Water Protection Section
Washington Regional Office
cc: David Ryan, PE, Bissell Professional Group, Inc.
Dare County Building Inspections Department
Washington Regional Office
Central Files
North Carolina Division of Water Quality Internet: ��rv�c.new:nan��ualilc.nre *TOn..e.L, 1
943 Washington Square Mall Phone (252) 946-6481 1V��ffQfthCarolina
Washington, NC 27889 Fax (252) 946-9215 Naturally
ly
An Equal Opportunity/Affirmative Action Employer- 50%Recyced/10% Post Consumer Paper !7 rbi K`Ltss
State Stormwater Management Systems
Permit No. SW7970115
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENT AND NATURAL RESOURCES
DIVISION OF WATER QUALITY
STATE STORMWATER MANAGEMENT PERMIT
HIGH DENSITY DEVELOPMENT
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
O.T. Enterprises, LLC
Dare County
FOR THE
construction, operation and maintenance of, stormwater management systems in compliance with the provisions of
15A NCAC 21-1.1000 (hereafter referred to as the "stormwater rulesl 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 for two wet detention ponds to serve the Hatteras Island Plaza, Phase 2
located at 41934 NC 12 at Kinnakeet Shores, Avon, NC.
This permit shall be effective from the date of issuance until March 23, 2017 and shall be subject to the following
specified conditions and limitations:
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 on page
2 of this permit, the Project Data Sheet.
3. A maximum of 313,259 square feet of built upon area is allowed on this 9.47 acre site.
4. All stomwater 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 approved plans.
5. Approved plans and specifications for this project are incorporated by reference and are enforceable parts of
the permit
Y
Project Name:
Permit Number:
Location:
Applicant:
Mailing Address:
Application Date:
Receiving Stream:
Classification of Water Body:
Total Site Area:
DIVISION OF WATER QUALITY
WET DETENTION POND - PROJECT DATA
Hatteras Island Plaza, Phase 2
SW7970115
Dare County
O.T. Enterprises, LLC
1648 E. North Market Drive
Raleigh. NC 27609
01 /22/2007
Pamlico Sound
SA
Drainage area:
Total Impervious allowed on site:
Wet Pond Depth:
Required Storage Volume:
Provided Storage Volume:
Required Surface Area:
Provided Surface Area:
Controlling Orifice:
Temporary Storage Elevation
9.47 ac
Pond # 1 (includes 2A. 2113. 2C, 2D. 2E & 2F)
Pond # 2
7.29 ac
0.55 ac
290,979 sf
22,279 sf
7.5 ft.
7.5 ft
34,722 cf
2,656 cf
165,032 cf
7,279 cf
11,445 sf
859 sf
161,407 sf
6,709 sf
no outlets
no outlets
4.5 ft. MSL
4.5 ft. MSL
6. No homeowner/lot owner/developer shall be allowed to fill in, alter, or pipe any vegetative practices (such as
swales) shown on the approved plans as part of the stormwater management system without submitting a
revision to the permit and receiving approval from the Division.
The following items will require a modification to the permit:
a. Any revision to the approved plans, regardless of size
b. Project name change
C. Transfer of ownership
d., Redesign or addition to the approved amount of built -upon area
e. Further subdivision of the project area.
In addition, the Director may determine that other revisions to the project should require a modification to the
permit
8. 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.
II. SCHEDULE OF COMPLIANCE
The permittee will comply with the following schedule for construction and maintenance of the stormwater
management system.
a. 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 surfaces except roads.
b. During construction, erosion shall be kept to a minimum and any eroded areas of the system will be
repaired immediately.
2. The facilities must be properly maintained and operated at all times. The approved Operation and
Maintenance Plan must be followed in its entirety and maintenance must occur at the scheduled intervals.
3. The permittee shall at all times provide the operation and maintenance necessary to assure the permitted
stormwater system functions at optimum efficiency including, but not limited to:
a. Semiannual scheduled inspections (every 6 months)
b. Sediment removal
C. Mowing and revegetation of side slopes
d. Immediate repair of eroded areas
e. Maintenance of side slopes in accordance with approved plans and specifications
f. Debris removal and unclogging of outlet structure, orifice device and catch basins and piping.
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. 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 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. Mail the Certification to the Washington Regional Office, 943 Washington Square Mall,
Washington, North Carolina, 27889, attention Division of Water Quality.
A copy of the approved plans and specifications shall be maintained on file by the Permittee for the life of the
permit
III. GENERAL CONDITIONS
1. This permit is not transferable. In the event there is a desire for the facilities to change ownership, or there is
a name change of the Permittee, a formal permit request must be submitted to the Division of Water Quality
accompanied by an application fee, 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.
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-
215.6(a) to 143-215.6(c).
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)
which have 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 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.
6. The Permittee, at least six (6) months prior to the expiration of this permit, shall submit in writing a request for
an extension along with appropriate application fee.
Permit issued this the twenty-third day of March, 2007.
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
L��
for Alan W. Klimek, P.E. Director
Division of Water Quality
By Authority of the Environmental Management Commission
Permit Number SW7970115
Hatteras Island Plaza, Phase 2
Stormwater Permit No. SW7970115
Designer's Certification
I, , as a duly
Registered Professional Engineer in the State of North Carolina, having been authorized to observe
(periodically/weekly/full time)
the construction of the 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.
Signature
Registration Number
Date
Certification Requirements:
_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.
Permit No. Il S
(to e prow e y 'J
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM �r-GEIVED
WET DETENTION BASIN SUPPLEMENT
This form may he photocopied for use as an original
JAN 2 2 2007
DWO Stormwater Management Plan Review: D Q-WARa
A complete stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications
showing all stormwater conveyances and system details.
L PROJECT INFORMATION
Project Name : Hatteras Island Plaza
Contact Person: Doug Marley, Bissell Professional Group Phone Number: (252) 261-3266
For projects with multiple basins, specify which basin this worksheet appliest to: Pond #1
elevations
Basin Bottom Elevation
Permanent Pool Elevation
Temporary Pool Elevation
-4.0 ft.
3.5 ft.
4.5 ft.
(floor of the basin)
(elevation of the orifice)
(elevation of the discharge stucture overflow)
areas
Permanent Pool Surface Area 161,407 sq. ft. (water surface area at the orifice elevation)
Drainage Area 7.29 ac. (on -site and off -site drainage to the basin)
Impervious Area 6.68 ac. (on -site and off -site drainage to the basin)
volumes
Permanent Pool Volume
Temporary Pool Volume
Forebay Volume
other parameters
SA/DA
Diameter of Orifice
Design Rainfall
Design TSS Removal
1,015,171 cu. ft.
165,032 cu. ft.
N/A cu. ft.
3.6 %
N/A in.
1.5 in.
90 %
(combined vlowne of main basin and forebay)
(volume detained above the permanentpool)
(approximately 20% of total volume)
(surface are to drainage area ratio from DWQ table)
(2 to 5 (lay temporary pool draw -down required)
(rninimmn 85% required)
* See attached narrative for explanation
Page 1 of 4
Form SWU-102 Rev.3.99
Footnotes:
l When using the Division SAIDA tables, the correct SAIDA 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 not
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 provid,
90% TSS removal. The NCDENR BMP manual provides design tables for both 85% TSS removal and 90% TSS removal.
11. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manu
(N.C. Department of Environment, Health and Natural Resources, February 1999) and Administrative Co(
Section: 15 A NCAC 2H .1008.
Initial in the space provided to indicate the following design requirements have been met and supportit
documentation is attached. If the applicant has designated an agent in the Stormwater Management Pern
Application Form, the agent may initial below. If a requirement has not been met, attach justification.
Applicants Initials
VA a. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
b. The-forebay volume is approximately equal to 20% of the basin volume.
0%%� c. The temporary pool controls runoff from the design storm event.
VA d. The temporary pool draws down in 2 to 5 days.
K)A— e. If required, a 30-foot vegetative filter is provided at the outlet (include non -erosive floc
calculations)
f. The basin length to width ratio is greater than 3:1.
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).
i. Vegetative cover above the permanent pool elevation is specified.
j. A trash rack or similar device is provided for both the overflow and orifice.
k. A recorded drainage easement is provided for each basin including access to nearest rig
of -way.
1. If the basin is used for sediment and erosion control during construction, clean out of tl
basin is specified prior to use as a wet detention basin.
L11A_ in. A mechanism is specified which will drain the basin for maintenance or an emergency.
III. WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and
vegetated filter if one is provided.
i
This system (check one) 0 does l does not incorporate a vegetated filter at the outlet.
This system (check one) 0 does does not incorporate pretreatment other than a forebay.
Form SWU-l02 Rev 3.99 Page 2 of 4 _ _
Maintenance activities.shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the 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. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi-annually or when depth is
reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed
of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality
(i.e. stockpiling near a wet detention basin or stream, etc.).
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.
When the permanent pool depth reads S- 6 ' feet in the main pond, the sediment shall be removed.
Whenthe permanent pool depth reads _0__ feet in the forebay, the sediment shall be removed.
BASIN DIAGRAM
(fill in the blanks)
s / Permanent Pool Elevation 6
Sediment Re oval El. N A ; V
-------------- Sediment Removal Elevation — 2 1375%
Bottom Ele ation A/ 4 --------------------------------------------- -----
Bottom
Elevation- `1 U 25%
FOREBAY MAIN POND
Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
Form SWU-102 Rev 3.99
Page 3 of 4
All components of the wet detention basin system shall be maintained in good working order.
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to an
changes to the system or responsible party. l
Print name:_ e
Date: - S -
Note: The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold ant
a resident of the subdivision has been named the president.
I, �ll�r��YY1 t���t(�1 t1 , a Notary Public for the State of rli +h Ca ; rt li` ty,
County of do hereby certify that --
byr\t n L1 ��1 crCU
personally appeared before me this day of,---7rc�-n ia( \-V- azo r I , and acknowledge the dui
execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal,
T
�Q A'Q�''vy
3
%
0
SEAL
My commission expires Ia19 2011.
Form SWU-102 Rev 3.99 Page 4 of 4
",
1JDate
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ecetveee
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Permit
Number
State of North Carolina RE�i��q(j1iflED
Department of Environment and Natural Resources �,p g
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM HAR 1 9'100
This form maybe photocopied for use as an original ���®
I. GENERAL INFORMATION OW
1. Applicants name (specify the name of the corporation, individual, etc. who owns the project):
O.T. Enterprises, LLC
2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance):
Brantley Tillman, Managing Member of O.T. Enterprises LLC
3. Mailing Address for person listed in item 2 above:
1648 E. North Market Drive
City: Raleigh State: North Carolina Zip: 27609
Telephone Number: (919) 872-5702
4. Project Name (subdivision, facility, or establishment name -should be consistent with project name on plans.
specifications, letters, operation and maintenance agreements, etc.):
Hatteras Island Plaza
5. Location of Project (street address):
41934 NC 12 AT KINNAKEET SHORES
City AVON
DARE
6. Directions to project (from nearest major intersection):
Entrance is approximately 700 FT. South of the intersection of Kinnakeet Boulevard and NC 12 in Avon Township
7. Latitude: 35d 20' 01.44" N Longitude: 75d 30' 25.54" W of project
8. Contact person who can answer questions about the project:
Name: Doug Marley, Bissell Professional Group Telephone Number: 252-261-3266
II. PERMIT INFORMATION:
1. Specify whether project is : New X Renewal x Modification
Form SWU-101 Version 3.99
Page I of
'.�& If this application is being submitted as a result of a renewal or modification to an existing permit, list the
existing permit number _S W7970115 and its issue date (if known) _04-10-97
3. Specify the type of project (check one):
Low Density X High Density Redevelop General Permit Other
4. Additional Project Requirements (check applicable blanks):
_CAMA Major _ Sedimentation/Erosion Control 404/401 Permit X NPD17S Stormwater
Information on required state permit can be obtained by contacting the Customer Service Center at
1-877-623-6748
111. 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.
runoff from all i
to two existine t
to an existine 21.2 acre
storm sewer system and vegetative swales
2. Stormwater runoff from this project drains to the _Pamlico Sound River Basin
3. Total Project Area: 9.47
acres
5. How many drainage areas does the project have? 2
4. Project Built Upon Area
75.96%
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.
„`Tu` ,`I3asmInfoririationh", Iti `�'—'
DrainageArea'I .t
; DrainageArea2 ,`
` "jDramageiArea3 :` ,."`:�:_
Receiving Stream Name
Pamlico Sound
Pamlico Sound
Receiving Stream Class
SA
SA
Drainage Area
7.29 ac.
0,548 ac.
Existing Impervious* Area
6.68 ac
0.511 ac.
Proposed Impervious* Area
0
0
Impervious* Area (total)
91.58%
93.38%
Impervious* Surface Area ;.
�: D�aitiage..Area 1 „M}
.,
Drainage Area 2 ,,,%,
wti , ,a i_Dmitiage Aii,a+3-;�+'r„;'
Future On -Site Buildings
0.0 ac.
0.0 ac.
On -Site Streets
0.0 ac.
0.0 ac.
On -Site Parking
0.0 ac.
0.0 ac.
Other On -Site
0.0 ac.
0.0 ac.
Off -Site
0.0 ac.
0.0 ac.
% Impervious* Area (total)
0.00%
0.00%
*Impervious area is defined as the built upon area including, but not limited to, buildings, roads, parking areas,
sidewalks, gravel areas, etc.
Form SWU-101 Version 3.99 Page 2of4
, ,1 7. How was the off -site impervious area listed above derived? No existing off -site impervious surfaces drain to the ponds.
IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS
The following italicized deed restrictoins 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.
I. The following covenants are intended to ensure ongoing compliance with state stormwater management permit
number _ SW7970115 as issued by the Division of Water Quality. These covenants
may not be changed or delted without consent of the State.
2. No more than _313,259 square feet of any lot shall be covered by structures or impervious materials.
Impervious materials include asphalt, gravel, concrete, brick, stone, slate or similar material but do not include
wood decking or the water surface ofswimming pools.
3. Swales shall not be filled in, piped, or altered except as necessray to provide driveway crossings.
4. Built -upon area in excess of the permitted amount requires a state stormwater management permit modification
prior to construction.
5. All permitted r nofffrom outparcels or fidure development shall be directed into the permitted stormwater control
system. 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 (919) 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 Pagc3 of4
VI. SUBMITTAL REQUIREMENTS
1'1
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.
1. Please indicate that you have provided the following required information by initialing in the space provided
next to each item.
Initials
• Original and one copy of the Stormwater Management Permit Application Form ► 26 R
• One copy of the applicable Supplement Form(s) for each BMP (�►"1 R
• Permit application processing fee of $420 (payable to NCDENR)
• Detailed narrative description of stormwater treatment/management
• Two copies of plans and specifications, including: - Ch B
- Development/Project name
- Engineer and firm
-Legend
- North arrow
- Scale
- Revision number & 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)_Q1SSs Lt. pF'srSIOU (jp��jV �� T�L
Mailing Address: (! O- nofpx 1 L)6Sr
City: k i =y 4A.W 1< State: _—_ Zip: 7?1� qcf
Phone: (_ 252 1 Z61 - -266 Fax: (Z52 1 ZG f76b
VIII. APPLICANT'S CERTIFICATION
I, (print or type name ofpersonlisted inGeneral Information, item 2) 13f-/4UTLEY Ti1.LLMAAI
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`*�H�/i— _ Date:
Form S WU-101 Version 3.99 Page 4 of 4
Permit No. S W% 9 i 6 1 l
to e provi e y
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form may be photocopied for use as an original
JAN 2 2 2007
DWQ-WARD
DWO Stormwater Management Plan Review:
A complete Stormwater management plan submittal includes a stormwater management permit application, an
infiltration basin supplement for each system, design calculations, soils report and plans and specifications
showing all Stormwater conveyances and system details.
I. PROJECT INFORMATION
Project Name : Hatteras Island Plaza
Contact Person: Doug Marley, Bissell Professional Group Phone Number: (252) 261-3266
For projects with multiple basins, specify which basin this worksheet appliest to: Pond #2
elevations
Basin Bottom Elevation -4.0 ft.
Permanent Pool Elevation 3.5 ft.
Temporary Pool Elevation 4.5 ft.
areas
Permanent Pool Surface Area 6,709 sq. ft.
Drainage Area 0.548 ac.
Impervious Area
volumes
0.511 ac.
(/loor of the basin)
(elevation of the orifice)
(elevation of the discharge stucture overflow)
(water surface area at the orifice elevation)
(on -site and off -site drainage to the basin)
(on -site and off -site drainage to the basin)
Permanent Pool Volume 25,892 cu. ft. (combined vloume of main basin and forebay)
Temporary Pool Volume 7,279 cu. ft. (volume detained above the permanent pool)
Forebay Volume N/A cu. ft. (approximately 20% of total volume)
other parameters
SA/DA 3.6 % (surface are to drainage area ratio from DWQ table)
Diameter of Orifice N/A in. (2 to 5 day temporary pool draw -down required)
Design Rainfall 1.5 in.
Design TSS Removal 90 % (minimum 85% required)
* See attached narrative for explanation
Page 1 of 4
Form SWU-102 Rev.3.99
Footnotes:
'! 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 nol
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 provid
90% TSS removal. The NCDENR BMP manual provides design tables for both 85% TSS removal and 90% TSS removal.
IL REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manu
(N.C. Department of Environment, Health and Natural Resources, February 1999) and Administrative Co,
Section: 15 A NCAC 2H .1008.
Initial in the space provided to indicate the following design requirements have been met and supporth
documentation is attached. If the applicant has designated an agent in the Stormwater Management Pern
Application Form, the agent may initial below. If a requirement has not been met, attach justification.
Applicants Initials
0 a. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
b. T tl�' forebay volume is approximately equal to 20% of the basin volume.
�%_ c. The temporary pool controls runoff from the design storm event.
VA d. The temporary pool draws down in 2 to 5 days.
WA e. If required, a 30-foot vegetative filter is provided at the outlet (include non -erosive floe
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).
i. Vegetative cover above the permanent pool elevation is specified.
j. A trash rack or similar device is provided for both the overflow and orifice.
k. A recorded drainage easement is provided for each basin including access to nearest rig
of -way.
_ 1. If the basin is used for sediment and erosion control during construction, clean out of tt
basin is specified prior to use as a wet detention basin.
_ in. A mechanism is specified which will drain the basin for maintenance or an emergency.
III. WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and
vegetated filter if one is provided.
This system (check one) 0 does es not incorporate a vegetated filter at the outlet.
This system (check one) 0 does 2oes not incorporate pretreatment other than a forebay.
Form SWU-102 Rev 3.99 Page 2 of 4 ._ -
Maintenance activities.shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the 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. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi-annually or when depth is
reduced to 75% of the original design depth (see diagram below). Removed sediment shall be disposed
of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality
(i.e. stockpiling near a wet detention basin or stream, etc.).
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.
When the permanent pool depth reads 5• G feet in the main pond, the sediment shall be removed.
When the permanent pool depth reads �i _ feet in the forebay, the sediment shall be removed.
BASIN DIAGRAM
(fill in the blanks)
y 5' Permanent Pool Elevation �' 6
Sediment Re oval El. 75 0
-------------- -- Sediment Removal Eievanon — Z • lY 75%
BottomSe anon. ok-------------------------------- ------------ ----
Bottom Elevation — `/' D � 25%
FOREBAY MAIN POND
Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
Form SWU-102 Rev 3.99 Page 3 of 4
7. All components of the wet detention basin system shall be maintained in good working order.
(i I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to an%
changes to the system or responsible party.
Print
Dater— � • Q3
d Ti k \NnCti
Note: The legally responsible parry 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.
I, 5l 1 SCkn '-M . ['� 13\ Ecc�� a Notary Public for the State of �j�AAk--) (,ac �) t i ra.,
County of s'Fi r1 do hereby certify that �P--)Y r. ✓\
personally appeared before me this day of 2 \ r t a ja=L U. C"\ , and acknowledge the due
execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official sea],
OTAct�°vy
Cj€
STUN CO�c"
SEAL
My commission expires MVCemmssim EVhs10-19-2011.
Form SWU-102 Rev 3.99
Page 4 of 4
Page 3
Permit No* S W iU 1 1 S
WET DETENTION BASIN OPERATION AND MAINTENANCF AGREEMENT RECEIVED
Maintenance activities shall be performed as follows:
1. After every significant runoff producing rainfall event and at least monthly: JAN 2 2
a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumul t —WARO
vegetated cover, and general condition. ``KK
b, Check and clear the orifice of any obstructiutu such thr i drawdow❑ of the temporary pool occur within
2 to 5 days as designed.
2. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow vegetative
cover to maintain a maximum height of six inches, and rcrnovc trash as needed.
3. Inspect and repair the collection system (i.e, catch basins, piping, swales, riprap, etc.) quarterly to maintain
proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi-annually ur when depth is reduced to
75"."a of the original design depth (see diagram below). Removed sediment shall be dispnsed of in an
appropriate manner and shall be handled in a manner that will not adversely impact water quality (i.e.
stockpiling near a wet detention basin or stream, etc.).
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.
When the permanent pool depth reads ,S.G feet in the main pond, the sediment shall be removed.
When the permanent pool depth reads t(//�. feet in the forebay, the sediment shall be removed.
BASIN DIAGRAM
(fill in the blanks)
-'-
'—fcrmancnt Paul Elevation
y % _ 3• `--- --- SeJiincol RanOval 131zvation ' l -
Bottom El�'atioq
FOREAAY MAIN PONT.)
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface, These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
G, If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment through
the emergency drain shall be minimized tv the maximum extent practical.