SW8040836_Current Permit_20191003

ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
S. DANIEL SMITH
Director
October 3, 2019
New Hanover County Airport Authority
Attn: Julie Wilsey, Director
1740 Airport Boulevard, Suite 12
Wilmington, NC 28405
NORTH CAROLINA
Environmental Quality
Subject: Permit Renewal
State Stormwater Management Permit No. SW8 040836
Wilmington International Airport Stormwater Master Plan Permit
New Hanover County
Dear Ms. Wilsey:
The Wilmington Regional Office received a complete 8 year Stormwater Management Permit Renewal
Application for Wilmington International Airport Stormwater Master Plan Permit on September 25, 2019. The
Division is hereby notifying you that permit SW8 040836 has been renewed on October 3, 2019, and shall be
effective until November 24, 2026. For your records, please find enclosed a renewed, updated, and re -issued
permit and a copy of the renewal application. Please keep this permit on file at all times. Please note that the
renewed, updated, and re -issued permit does not impose new or different terms; it merely restates some of the
previous terms to provide you with a better understanding of your obligations under the permit.
The renewal and reissuance of this stormwater permit does not imply that the site is currently in compliance
with the terms and conditions of this state stormwater permit. The plans originally approved on November 19,
2004 and subsequently modified on December 19, 2008, July 12, 2010, August 22, 2011, March 13, 2012, July
23, 2012, August 6, 2012, October 4, 2012, June 11, 2014, and January 4, 2016, will remain in full force and
effect in accordance with the regulations set forth in Title 15A NCAC 2H.1000 effective September 1, 1995.
This permit is subject to the conditions and limitations as specified therein. Please pay special attention to the
conditions listed in this permit regarding the Operation and Maintenance of the BMP(s), recordation of deed
restrictions, procedures for changes of ownership, transferring the permit, and renewing the permit. Failure to
establish an adequate system for operation and maintenance of the stormwater management system, to record
deed restrictions, to transfer the permit, or to renew the permit, 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 by filing a written petition with the Office of Administrative Hearings (OAH).
The written petition must conform to Chapter 150B of the North Carolina General Statutes, and must be filed
with the OAH within thirty (30) days of receipt of this permit. You should contact the OAH with all questions
regarding the filing fee (if a filing fee is required) and/or the details of the filing process at 6714 Mail Service
Center, Raleigh, NC 27699-6714, or via telephone at 919-431-3000, or visit their website at
www.NCOAH.com. Unless such demands are made this permit shall be final and binding.
If you have any questions, need additional copies of the permit or approved plans, please contact Garrett Zorda
at [phone] or via email at [e-mail].
Sine rely,
Danny Smith, Interim Director
Division of Energy, Mineral and Land Resources
GDS/gdz: \\\Stormwater\Permits & Projects\2004\040836 HD\2019 10 permit 040836
cc: Wilmington Regional Office Stormwater File
North Carolina Department of Environmental Quality I Division of Energy, Mineral and Land Resources
c DO E Wilmington Regional Office 1 1127 Cardinal Drive Extension I Wilmington, North Carolina 28405
Now CAR
910.796.7215

State Stormwater Management Systems
Permit No. SW8 040836
STATE OF NORTH CAROLINA
DEPARTMENT OF ENVIRONMENTAL QUALITY
DIVISION OF ENERGY, MINERAL AND LAND RESOURCES
STATE STORMINATER MANAGEMENT PERMIT
OVERALL LOW DENSITY DEVELOPMENT
WITH ENGINEERED CONTROLS FOR POCKETS OF HIGH DENSITY
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
New Hanover County Airport Authority
Wilmington International Airport Stormwater Master Plan
1740 Airport Blvd., Wilmington, New Hanover County
FOR THE
construction, operation and maintenance of an overall low density project with dry detention ponds
and grassed swales for treatment of the pockets of high density, as determined by the Division, 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 Energy, Mineral and Land Resources
(the "Division" or "DEMLR") and considered an enforceable part of this permit.
This permit shall be effective from the date of issuance until November 24, 2026, and shall be subject
to the following specified conditions and limitations:
I. DESIGN STANDARDS
1. This permit is for the Master Plan of development and is effective only with respect as to how
the stormwater from the Airport property will be treated prior to discharge into surface waters,
as described in the application and other supporting data.
2. The proposed method of treatment for the designated pockets of high density is extended dry
detention basins with grassed swales to provide a minimum of 85% TSS removal.
3. Specific stormwater control measures will be permitted on a case by case basis. Design
criteria for the proposed controls must be from the most recent version of the stormwater rules.
A permit application or permit modification must be submitted and approved prior to
development of any additional built -upon area within the 1620.8-acre airport property.
4. In order to maintain overall low density, the 1620.8-acre airport tract will be limited to no more
than 486.2 acres of built -upon area. Currently, there are 303.858 acres of existing built -upon
area, leaving 182.342 acres available for future development. Development of projects within
those areas determined to be high density, or development which creates a pocket of high
density, as determined by the Division, must provide dry detention basins in combination with
grassed swales in accordance with the design criteria contained in the latest version of the
stormwater rules. At the point where the overall built -upon area exceeds the limit of 486.2
acres, engineered controls will be required for all development that has taken place to date.
5. The engineering report received on October 26, 2004, and the modified plan sheet #2
prepared by Talbert & Bright and received on November 8, 2004, delineates the existing high
Page 1 of 4

State Stormwater Management Systems
Permit No. SW8 040836
density pockets. All new built -upon area or redeveloped built -upon area within these pockets
must be treated with an extended dry detention basin and grassed swale. Maintenance
activities such as the repair or overlayment of runways are not redevelopment activities. The
Division shall determine which proposed activities are considered maintenance and which are
redevelopment, high density and low density.
6. The runoff from all built -upon area within the permitted future drainage areas of the designated
pockets of high density within this project must be directed into the future permitted stormwater
control systems.
7. There are no restrictions on the type of stormwater system that can be used at this project.
However, the shallow water table prohibits the use of infiltration basins or trenches, and the
FAA prohibits the use of engineered methods that create a permanent pool of water.
8. If new impervious areas are proposed, which are located adjacent to or in the same area as
the delineated pre-1988 impervious areas, and which result in the creation of a pocket of high
density as determined by the Division, then all of the runoff within that pocket of high density
must be treated in a dry detention basin system unless the runoff from the pre-1988 area can
be separated from the new area. If new built -upon area is proposed adjacent to or in the same
area as existing post-1988 built -upon area, and which result in the creation of a pocket of high
density, then all of the runoff within that pocket must be treated in a dry detention basin
system.
9. All low flow channels in the dry detention basins must be stabilized with rip rap. Concrete
channels are not allowed.
10. The bottom of any proposed extended dry detention basin must be at least 1' above the
seasonal high water table. All due diligence must be exercised to find a suitable site that
meets this requirement. If not, the system will not draw down as intended and may result in a
permanent pool of water, contrary to FAA requirements.
11. The FAA has recommended that the plunge pool at the outlet structure of the dry detention
basin be eliminated. This will increase the potential for clogging of the orifice, and will require a
more frequent inspection schedule.
12. Projects submitted for approval under the low density option must demonstrate compliance
with the low density criteria described in the latest version of the stormwater rules. Projects
that have clustered built -upon area, collection systems, or which do not provide for sheet flow
across at least 30' of grassed area will be considered high density.
II. SCHEDULE OF COMPLIANCE
Once approved, the permitted 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.
3. Access to the stormwater facilities for the purposes of inspection by DEQ personnel and
maintenance by airport personnel shall be maintained at all times.
4. The facilities shall be constructed, operated and maintained in accordance with the provisions
of this permit, the approved plans and specifications, and the supporting documents attached
to this permit and on file with the Division.
5. The permittee shall at all times provide the operation and maintenance necessary to assure
the permitted stormwater system (dry detention basin and grassed swales) functions at the
design condition. The Operation and Maintenance Plan must address the following items:
a. Monthly inspections. More frequent inspection will be required if there is construction
activity within the drainage area of the basin.
b. Sediment removal.
Page 2 of 4

State Stormwater Management Systems
Permit No. SW8 040836
C. Mowing and revegetation of slopes. Woody vegetation must be removed.
d. Immediate repair of eroded areas.
e. Maintenance of all slopes in accordance with approved plans and specifications.
f. Debris removal and unclogging of basin, outlet structure, orifice device, catch basins,
piping and swales.
g. Access to the outlet structure must be available at all times.
6. Records of maintenance activities must be kept and made available upon request to
authorized personnel of DEMLR. The records will indicate the date, the condition of the facility,
any problems, the name of person performing the work and what preventative or corrective
actions were taken.
7. Upon completion of construction, prior to issuance of a Certificate of Occupancy, and prior to
operation of the permitted future facility, a certification must be received from an appropriate
designer for the system installed certifying thafthe 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.
B. If the future stormwater system is 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.
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
stormwater 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., that has an impact on the
permitted stormwater facility.
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.
10. The permittee shall submit final site layout and grading plans for all future development areas,
to the Division prior to construction.
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
writino to the Director that the changes have been made.
III. GENERAL CONDITIONS
This permit is not transferable to any person or entity except after notice to and approval by
the Director. The permittee shall submit a completed and signed "Permit Transfer Application
Form" (available on the Division website) accompanied by the required fee and supporting
documentation as listed on the form, to the Division at least 60 days prior to any one or more
of the following events:
a. The sale or conveyance of the project area in whole or in part, except in the case of an
individual lot sale this is made subject to the recorded deed restrictions and protective
covenants;
b. Dissolution of the partnership, corporate, or LLC entity, subject to NCGS 55-14-05 or
NCGS 57D-6-07 and 08;
Page 3 of 4

State Stormwater Management Systems
Permit No. SW8 040836
C. Bankruptcy;
d. Foreclosure, subject to the requirements of Session Law 2013-121;
2. Any individual or entity found to be in noncompliance with the provisions of this stormwater
management permit or the requirements of the Stormwater rules is subject to enforcement
procedures as set forth in NCGS 143 Article 21.
3. The permittee is responsible for compliance with all permit conditions until such time as the
Division approves the transfer request. Neither the sale of the project, in whole or in part, nor
the conveyance of common area to a third party constitutes an approved transfer of the
stormwater permit.
4. 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_
5. 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.
6. The permittee grants DEQ Staff permission to enter the property during normal business hours
for the purpose of inspecting all components of the permitted stormwater management facility.
DEQ staff shall identify themselves and the permittee shall provide an escort, as required by
FAA requirements.
7. The permit issued shall continue in force and effect until the permittee files a request with the
Division for a permit modification, transfer, renewal, or rescission; however, these actions do
not stay any permit conditions.
8. Unless specified elsewhere on the plans, permanent seeding requirements for the stormwater
controls will follow the FAA Standard Specification for seeding, mulching and erosion control
where they do not conflict with the intent of the North Carolina Erosion and Sediment Control
Planning and Design Manual.
9. Approved plans and specifications for this project are incorporated by reference and are
enforceable parts of the permit.
10. Current Permittee Name or Address Changes: The permittee shall submit a completed
"Permit Information Update Application Form" (available on the Division website) to the
Division within 30 days to making any one or more of the following changes:
a. A name change of the current permittee;
b. A name change of the project;
c. A mailing address change of the permittee;
11. A permit renewal request must be submitted at least 180 days prior to the expiration date of
this permit. The renewal request must include the appropriate application, documentation and
the processing fee as outlined in Title 15A NCAC 02H.1045(3).
Permit updated, renewed and reissued this the 3ro day of October 2019
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
Danny Smith, Director
Division of Energy, Mineral and Land Resources
By Authority of the Environmental Management Commission
Page 4 of 4

P, DEMLR USE ONLY
Date
sceiv d
Fee Paid
Permit Number
'
NC DEQ Division of Energy, Mineral and Land Resources
STATE STORMWATER:
PERMIT RENEWAL APPLICATION FORM
In accordance with 15A NCAC 2H.1045(3), the current permit holder shall renew their high density permit 180 days
prior to its expiration. Renewed permits are valid for a period of 8 years per Session Law 2011-398 (SB 781)
Section 60.(c). This application form is for permit renewals only.
A. PROJECT INFORMATION
1. State Stormwater Permit Number: SW8 040836
2. Project name: Wilmington International Airport Stormwater Master Plan Permit
3. Project street address: 1740 Airport Boulevard, Suite 12
City: Wilmington County: New Hanover
ZIP: 28405
4. What, if any, changes have been made to the project as permitted? No chancepermit basis:
Overall low density with high density pockets, SW management using swales and dry detention
If the project has changed from the original approved plans, please complete SWU-101 fora Major
Modification or Minor Modification Application form available at. hfps://deg.nc.gov/about/divisions/energy-
m ineral-land-resources/energy-mineral-land-rules/stormwater-prop ram/post-construction.
B. PERMITTEE INFORMATION
if changes to the permittee or project name have been made, please complete either the Permit Update form
or the Permit Transfer form available at: https://deg.nc.gov/about/divisions/energy-mineral-land-
resources/energy-mineral-land-rules/stormwater-program/post-construction. State Stormwater Permits do not
automatically transfer with the sale of the property.
1. Current Permit Holder's Company Name/Organization: New Hanover County Airport Authority
2. Signing Official's Name: Julie Wilsey
3. Signing Official's Title: Airport Diretor SEP 2 S 2019
4. Mailing Address: 1740 Airport Boulevard, Suite 12 BY'
City: Wilmington State: NC ZIP:
28405
5. StreetAddress: same
Citv: State: ZIP:
6. Phone: [phone] Email: iwilsey(a)_fiyilm.com
WI-ruir`valf3r, i'errr:i Fiuir 'i c6 33
s'uuc : 1 i . 2C 1 F

C. SUBMITTAL REQUIREMENTS
Submit the application package to the appropriate DEMLR Regional Office (Coastal, SA Waters) or DEMLR
Central Office (Urbanizing Areas Ph 2, USMP, Non -Coastal HQW/ORW). Only applications packages that
include all required items listed below will be accepted and reviewed.
Initial each item below to indicate that the required information is provided in the application package:
1. A permit application processing fee of $505.00 payable to NCDEQ.
2. One original signed hard copy and one electronic copy of this completed form. The signing official
N 4.
named on this application to represent the current permittee must meet one of the following:
a. Corporation — a principle executive officer of at least the level of vice-president;
b. Limited Liability Company (LLC) — a manager or company official as those terms are defined
in G.S. 57D "North Carolina Limited Liability Company Act;"
c. Public Entity — a principal executive officer, ranking official, or other duly authorized employee;
d. Partnership or limited partnership — the general partner;
e. Sole proprietor; or
f. Letter of authorization signed by one of the signatories noted in a - e above authorizing the
signature of another entity.
One hard copy and one electronic copy of recorded documents required by the original permit that
have not yet been received by DEMLR, including: deed restrictions, protective covenants,
condominium/planned community declaration and easements. If the project has been built, include
documentation that the maximum BUA per lot or maximum total BUA has not been exceeded. If
the project has not been built, include a signed agreement that the final recorded deed restrictions
and protective covenants will be submitted at a later date.
O&M Agreements, Please select one:
® I have a copy of the current recorded O&M Agreement for all SCMs, and I will continue to
keep this on file with the permit; or
❑ I do not have a copy of the current recorded O&M Agreement for all SCMs and am
requesting a copy be sent to me. I agree to keep this on file with the permit.
Designer Certifications, Please select one:
® A copy of the certification(s) confirming that the project was built in accordance with the
approved plans have been previously provided to the Division; or
❑ A copy of the certification(s) confirming that the project was built in accordance with the
approved plans are enclosed; or
❑ The project has not yet been built.
6. [IF APPLICABLE] If the project has been built, one original hard copy and one electronic copy of a
signed, sealed, and dated letter from a licensed professional stating that the SCMs have been
inspected, and that they have been built and maintained in accordance with the permit.
7. [IF APPLICABLE] When the permittee is a corporation or a limited liability corporation (LLC):
Provide one hard copy and one electronic copy of documentation from the NC Secretary of State,
or other official documentation, which supports the titles and positions held by the persons listed in
Section C.2 per 15A NCAC 2H. 1043(3)(b).
https://www.sosnc.gov/online services/search/by title/ Business Registration
ECI .,
.,:
SEP 2 5 2019
i
13�'.—
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r
D. PERM ITTEE'S CERTIFICATION
I, J a] A,lj, the person legally responsible for the permit, certify that I have
a copy of the Permit and O&JA Agreement on site (or I will obtain a copy and it will be kept on site), that I am
responsible for the performance of the maintenance procedures, and the site has been and will be maintained
according to the O&M Agreement and approved plans. I agree to notify DEMLR of any problems with the SCMs
or built -upon area and to submit the proper forms to modify or transfer the permit prior to any changes to the
project, SCMs r ownership. All information provided on this permit renewal application is, to the best of my
knowledge, r ct nd cR�l
Signature: Date:
W91I
I, , Kose M.
Ndvf-L Ca.,c
that
LVI S
a Notary Public for the State of
County of )v&A-) I M0 V41— , do hereby certify
day of 17)e- `f r�-►e-e- ,
instrument. Witness my hand and official seal,
z `PC��ICeaf) z
1k, `
My commission expires
personally appeared before me
20-Lq--, and acknowledge the due
r
SEP 2 5 2019
St{ nn-, alor P`,3if11 t Renewal �,p plicaii. �"orrr. Page 3 cf 3 ;�;;;�y 1' ' 1
i,

Permit No.
(To be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
EXTENDED DRY DETENULON BASIN SUPPLEMENT
This form may be photocopied for use as an original.
DWO Stormwater Management Plan Review:
A comp ete stonnwater rnanaagement plan submittal includes a dry detention basin supplement for each basin,
design calculations, plans and specification showing all basin and outlet structure details, and a fully executed
operation and maintenance agreement.
I. PROJECT INFORMATION (Please complete the following information):
Project Name: W I LM IrJ47b M /,
"4VVVL PL41�3
E
Contact Person: ZRI c. sw3O�1S WILSNN Phone Number: �& S-a5
For projects with multiple basins, specify which basin this w� orrksheet applies. to: 0 ttj
Design Storm: (Please mark one) 01 yr, 24 hr storm L�f 1" storm A)°' I (6-A D$:0
Drainage Area: 32-f AC- 9qw"4eet
Required Volume: 11,3(o 14G• Fr Gwgefeet
A&
a
Built -upon Area:
SHWT elevation: FMSL
Basin Dimensions: ,a w F cLow G' "r JCL f N llE-7— 'j,D
Bottom Elevation: ;�'1 10 feet, MSL Area: /OOa ft long x —/& _ft wide = % 6/ b 00 ft2
Storage Elevation: 12-2 feet, MSL Area: l7-oo ft long x 5-60s ft wide= 59B 890` ft2
Detention Volume Provided: i , (o �
Sediment Storage Provided: 3 , oubie•feet (Equivalent to 20% of the detention volume)
Sediment Storage Elevation: C b 4 7 FMS
Drawdown Orifice: 3— .5 �f � t�2t A F f O'-6 !N 7, t�
(Please andacate size and type of orifice)
Required Additional $MP to achieve a total of 85% TSS (check one):
& Grassed swale -OVegetated Filter ❑ Other
piLt,�! 5YZC nr(- 4CC-,o►.K J0L-cJA'l&b U,S r •-✓b-

Type.... Vol: Elev-Area Page 1.01
Name.... P 20
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 2 SOLUTION SOUTH.PPW
Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum
(ft) (sq.in) (sq.ft) (sq.ft) (ac-ft) (ac-ft)
------------------------------------------------------------------
7.00 ----- 0 0 .000 .000
8.00 ----- 7000 7000 .054 .054
9.00 ----- 16000 33583 .257 .311
10.00 ----- 116170 175283 1.341 1.652
10.70 ----- 304037 608143 3.258 4.909
10.80 ----- 330780 951944 .728 5.638
11.00 ----- 382445 1068901 1.636 7.274
12.00 ----- 591733 1449894 11.095 18.369
13.00 -- -- 627496 1828581 13.993 32.36 L�(7F� -1
14.00 ----- 649276 1915065 14.655 47.016
15:00 ----- 671114 1980495 15.155 62.172
16.00 ----- 693012 2046101 15.657 77.829
17.00 ----- 714967 2111883 16.161 93.990
18.00 ----- 736982 2177840 16.665 110.655
19.00 ----- 759054 2243973 17.172 127.827
20.00 ----- 781186. 2310281 17.679 145.505
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq_rt.(Area1*Area2))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
6-c .. - -C) e"vJr(ov-.) am , -i No. 7
5ei)I Aot C-Nr kj-t-o.�j Pajc. .
S/N- C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 17:10:09 Date: 08-23-2004

Type.... Vol: Elev-Area Page 1.01
Name.... P 20
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 2 SOLUTION SOUTH.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
------------------------------------------------------------------------
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
7.00
----- 0
0
.000
.000
.8.00
----- 7000
7000
.054
.054
9.00
----- 16000
33583
.257
.311
10.00
----- 28000
65166
.499
.809
10.70
----- 40000
101466
.544
1.353
10.80
---- 330780
485807
.372
1.724
11.00
----- 382445
1068901
1.636
3.360
12.00
----- 591733
1449894
11.095
14.455D
13.00
----- 627496
1828581
13.993
28.448
14.00
----- 649276
1915065
14.655
43.103
15.00
----- 671114
1980495
15.155
58.258
16.00
----- 693012
2046101
15.657
73.915
17.00
----- 714967
2111883
16.161
90.076
18.00
----- 736982
2177840
16.665
106.742
19.00
----- 759054
2243973
17.172
123.913
20.00
----- 781186
2310281
17.679
141.592
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt_(Areal*Areal))
where: ELL EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
)X D ( ) -- N [ AL5 ti �-j a , 1
vo 1. �,� . 12,C--fN) j C2;�) (.-* /L- S 4--V L ^1 Q-T- .
A= S-7-9 roc. � ��56`� �✓- (, 007)(w) +.05�
V0L_ _ ,&3s q
32 � 17►3� A-C,Fr
X ZOYo = 3,`f7A4c.- FT
%,17' Ac•Fr
L C--
33.�7
SIN: C21705506AB7 Talbot & Bright
PondPack Ver: 7.0 (325) Compute Time: 17:09:08
sue, L,4v0
1000
Date: 08-23-2004

Type.... Outlet Input Data
Name.... PR 20
Page 6.12
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 2 SOLUTION SOUTH.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID
Structure Type = Orifice -Circular
# of Openings = 3
Invert Elev. = 7.00 ft
Diameter = .4375 ft
Orifice Coeff. _ .632
Structure ID
Structure Type = Culvert -Circular
No. Barrels =
1
Barrel Diameter =
2:flOW ft
Upstream Invert =
15.00
ft
Dnstream Invert =
14.70
ft
Horiz. Length =
100.00
ft
Barrel Length =
100.00
ft
Barrel Slope =
.00300
ft/ft
OUTLET CONTROL DATA...
Mannings n = .0150
Ke = .5000 (forward entrance loss)
Kb = .016523 (per ft of full flow)
Kr = .5000 (reverse entrance loss)
HW Convergence = .001 +/- ft
INLET -CONTROL DATA..
Equation form =
1
Inlet Control K =
.0078
Inlet Control M =
2.0000
Inlet Control c =
.02920
Inlet Control Y =
.7400
T1 ratio (HW/D) =
1.134
T2 ratio (HW/D) =
1.206
Slope Factor =
-.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 17:27 ft ---> Flow = 15.55 cfs
At T2 Elev = 17.41 ft ---> Flow = 17.77 cfs
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 14:47:22 Date: 08-20-2004

Permit No.
(To be provided by DW(2
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
ST.ORMWATER MANAGEMENT PERMIT APPLICATION FORM
EXTENDED DRY DETENTION BASIN SUPPLEMENT
This form may be photocopied for use as an original.
DWO Stormwater M a ement Plan Review:
A complete stormwater management pan submittal includes.a dry detention basin supplement for each basin,
design calculations, plans and specification showing all basin and outlet structure details, and a fully executed
operation and maintenance agreement.
I, PROJECT INFORMATION (Please complete the following information): p
Project Name: Wi"L4(J47'4J /,�7-NAri'70�vf}t. /4�Q,�6tr Smamui,
Contact Person: ERi C W 7V �PK Phone Number: `7&a sa S
For projects with multiple basins, specify which basin this worksheet applies. to: r- U O (A)
Design Storm: (Pl��eaIs//ee ymark one) 01 yr, 24 hr storm " storm /`�o • Z • C�DD g2�
Drainage Area.: l -
Required Volume:
Built -upon Area: 60 -0 69�"
SHWT elevation: / a FMSL
Basin Dimensions: 1®1A1 f-t oW e k4V1J i 1AJV Zo , 5
Bottom Elevation: `(, S feet, MSL Area: i00 D ft long x / D : ft wide = © 000 ft2
Storage Elevation: 'L3, feet, MSL Area:? o ft long x ! gO ft wide=l 79v ft2
Detention Volume Provided: Slog A-C- �
i}cFt'
Sediment Storage Provided: eubieeet (Equivalent to 20% of the detention volume)
Sediment Storage Elevation: 22 FMSL
Drawdown Orifice: ' S /$ VOL-61 N✓ 2p' �c
(Please indicate size and type of orifice)
Required Additional 4W to achieve a total of 85% TSS (check one):
96rassed swale Vegetated Filter ❑ Other
/l/b�'�� •a��2r�c� S< z�r✓c:� /�-c c.�,�-t Pc.rd/f�� vs� �G-
������-

Type.... Vol: Elev-Area
Name.... P 30
Page 1.01
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 20 SOLUTION NORTH.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
------------------------------------------------------------------------
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
20.50
----- 0
0
.000
.000
21.50
----- 10000
10000
.077
.077
22.00
----- 77900
115811
.443
.520
22.20
----- 134795
315167
.482
1.002
22.30
----- 163242
446375
.342
1.344
22.40
----- 191690
5318.27
.407
1.751
22.50
----- 220137
617249
.472
2.223
23.00
----- 372566
879087
3.364
5.586 4c —
24.00
----- 478131
1272758
9.740
15.326
25.00
26.00
----- 501649
----- 525371
1469529
1540393
11.245
11.788
26.571
38.359 (6-b
27.00
----- 549292
1611861
12.334
50.693
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Areal + sq.rt.(Area1*Area2))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
Fuu' VOLOKf ('81Et:64L.0 $Mf K0
STOL4vc "KWO o�
E "'K TKO M D (-I . D -)-1700
SAS W No,
cirri. r2l" eO7 � t
«,,,5506„U, IaLberL « o� igii�
PondPack Ver: 7.0 (325) Compute Time: 09:54:46 Date: 08-20-2004

Type.... Vol: Elev-Area Page 1.01
Name.... P 30
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 20 SOLUTION NORTH.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
------------------------------------------------------------------------
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
20.50
----- 0
0
.000
.000
21.50
----- 10000
10000
.077
.077
22.00
----- 14000
35832
.137
.214
22.20
----- 16000
44967
.069
.282
22.30
----- 17000
49492
.038
.320
22,40
"'n2.50
----- 18000
52493
.040
.360
----- 220137
301085
.230
.591
23.00
----- 372566
879087
3.364
3.954 <'
24.00
----- 478131
1272758
9.740
13.694
25.00
----- 501649
1469529
11.245
24.939
26.00
----- 525371
1540393
11.788
36.727
27.00
----- 549292
1611861
12.334
49.061
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 +'sq.rt.(Areal*Areal))
where: tL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume T = Increemental volume between EL1 and EL2
St SBCo
�qSq At, - Pr
(0011/0 E vAP Vr aas
R.► n��) ('1610)+ .10 S
S9n
'r fJot.;
1 -21 .9 �/,
S/N: C21705506AB7 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 09:58:40 Date: 08-20-2004

Type.... Outlet Input Data
Name.... PR 30
Page 6.04
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 20 SOLUTION NORTH.PPW
OUTLET STRUCTURE INPUT DATA
,i cture ID
Structure Type = Orifice -Circular
# of Openings = 2
Invert Elev. = 20.50 ft
Diameter = .4271 ft
Orifice Coeff. _ .632
Structure ID
Structure Type = Culvert -Circular
No. Barrels =
1
Barrel Diameter =
2.5000
ft
Upstream Invert =
23.20
ft
Dnstream Invert =
22.50
ft
Horiz. Length =
30.00
ft
Barrel Length =
30.01
ft
Barrel Slope =
.02333
ft/ft
OUTLET CONTROL DATA...
Mannings n = .0150
Ke = .2000 (forward entrance loss)
Kb = .012271 (per ft of full flow)
Kr = .5000 (reverse entrance loss)
HW Convergence = .001 +/- ft
INLET CONTROL DATA...
Equation form =
1
Inlet Control K =
.0078
Inlet Control M =
2.0000
Inlet Control c =
.02920
Inlet Control Y =
.7400
T1 ratio (HW/D) =
1.124
T2 ratio (HW/D) =
1.196
Slope Factor =
-.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 26.01 ft ---> Flow = 27.16 cfs
At T2 Elev = 26.19 ft ---> Flow = 31.05 cfs
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 16:32:51 Date: 08-23-2004

Permit No.
(To be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STOR.MWATER MANAGEMENT PERMIT APPLICATION FORM
EXTENDED DRY DETENTION BASIN S JPPLErAENT
This form may be photocopied for use as an original.
DWO Stormwater Management Plan Review:
A complete stormwater management plan submittal includes a dry detention basin supplement for each basin,
design calculations, plans and specification showing all basin and outlet structure details, and a fully executed
operation and maintenance agreement.
I. PROJECT INFORMATION (Please complete the following information): u
Project Name: W 11-M (AJ471N /M i�YZ�t}�?pN /�t,2Pa T- 5Tba f1tj1Atr L j-I*CTp1L PL +J
ZML1E WILSE
Contact Person:_ fAl C, SW„ 4 00H Phone Number: � ��3 5 3 S
For J ro'ects with multi le basins i +ls3r
P p ,specify which basin this worksheet applies. to: �l s712,t i3cJ7Z� c'.orJ ct'hi
Design Storm: (Please mark one) 01 yr, 24 hr storm " storm
l'{ kc-
Drainage Area: —SS.., I I - sq'eet Built -upon Area: GS 10 s
Required Volume: 1►7 t ", FT- eOtbie- t SHWT elevation: (`Z FMSL
Basin Dimensions: a `"� F `'n t4 Cft'4-NV62- //Jv, 2,010
T
Bottom Elevation: . 0 feet, MSL Area: 2?U ftlong x --JD ftwide=__Zy0J ft2
Storage Elevation: Z3.3 feet, MSL Area: 930 ft long x *7 d ft wide= to - p ft2
Detention Volume Provided: (, 7 L{ Af- ' F - e 4e c -
Sediment Storage Provided: 01
3S •Fr(Equivalent to 20% of the detention volume)
Sediment Storage Elevation: i0 FMSL
Drawdown Orifice: `! �� 3/� t /{� Lt= (Pleaseid ate size and type of orifice)
Required Additional $VIP to achieve a total of 85% TSS (check one):
96rassed swale -OVegetated Filter ❑ Other
o 12cFr&6 4--C-c.a,k Pt.< JkeCs�✓a-
12- &y6AVo t d- r66,/7? AJ&- , S e' A/JC-d-t- �<leN D

Type.... Outlet Input Data
Name.... PR 20
Page 6.03
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\TERMINAL AREA DRY POND
POSTB.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID =
Structure Type = Orifice- ular
------------------------------.�
# of Openings = 1
Invert Elev. 20.00 ft
Diameter = .2708 ft
Orifice Coeff. _ .632
Structure ID
Structure Type = Weir -Rectangular
-------------
# of Openings = 1
Crest Elev. = 26.60 ft
Weir Length = 18.00 ft
Weir Table File: WEIR TAB.WCT
Weir Table ID: Weir C 10
WEIR COEFFICIENT TABLE
Depth, ft Weir C
.20
2.6900
.40
2.7200
.60
2.7500
.80
2.8500
1.00
2.9800
1.20
3.0800
1.40
3.2000
1.60
3.2800
1.80
3.3100
3.00
3.3200
Weir TW effects (Use adjustment equation)
'p ( Sie2 l &Ifv
SIN: C2170550GA87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 10:55:34 Date: 08-09-2004

Type.... Executive Summary (Nodes) Page 1.01
Name.... Watershed Storm: 1" Eq
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\TERMINAL AREA DRY POND
POSTB.PPW
Storm... TypeIII 24hr Tag: 1" Eq
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storer File,ID = NHC.RNQ NHC
Storm Tag Name = 1" EgtS7�t�
--- - --- --------------------------------
Data Type, File, ID = Synthetic Storm SCSTYPES.RNF TypeIII 24hr
Total Rainfall Depth= 1.7700 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
HYG Vol
Qpeak
Qpeak Max WSEL
Node
ID
Type
ac-ft
Trun. hrs
cfs ft
AREA
D1
AREA
-------
.712
-- ---------
12.3000
-------- ---------
6.12
AREA
D2
AREA
.313
12.2000
2.96
AREA
D3
AREA
.108
12.3000
.91
AREA
D4
AREA
243
12.1500
2.54
AREA
D5
AREA
373
12.2000
3.59
Outfall OUT
10
JCT
1.748
17.3500
.49
P 10
IN POND
1.748
12.2500
15.53
P 10
OUT POND
1.748
17.3500
.49 22.98
I c- - r — 9ES v Q j41- 1=-,� sk,� 1,?,7 It2 �- K 0- RAl k4f&.
e11 UI -�`-� ► t I sTti4-" (LvtiorF FZ5-"
�J = .009 (1) t , vS
1^ Ca S pro t Perw ovs 0, 63 S
7.
e t'c't Ax+e W4 ti `�8 �n-S
oK,
SIN: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 10:55:34 Date: 08-09-2004

Type.... Vol: Elev-Area
Name.... P 10
Page 5.01
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\TERMINAL AREA DRY POND
POSTB.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
--------------------------------------------------------------------------
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
21.00
----- 2800
2800
.021
.021
22.00
----- 6000
12899
.099
.120
22.10
----- 45278
67760
.052
.172
23.00
----- 62258
160630
1.106
1.278
24.00
----- 71922
201096
1.539
2.817
25.00
----- 78379
225382
1.725
4.542
26.00
----- 84934
244904
1.874
6.416 ,p(�
27.00
----- 91430
264486
2.024
8.440
28.00
----- 97969
284042
2.174
10.613
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Areal))
where: EL1, EL2 . = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
V O L vvA e '?—C)u cet� ZLII-
SIN: C2170550GA87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 10:55:34 Date: 08-09-2004

Type.... Vol: Elev-Area Page 1.01
Name.... P 10 (5.o1 A)
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\TERMINAL AREA DRY POND
POSTB.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
21.00
----- 2800
2800
.021
.021
22.00
----- 45278
59338
.454
.475
23.00
----- 62258
160630
1.229
1.705
24.00
----- 71922
201096
1.539
3.244
25.00
----- 78379
225382
1.725
4.968
26.00
----- 84934
244904
1.874
6.842
27.00
----- 91430
264486
2.024
8.866
28.00
----- 97969
284042
2.174
11.040
r
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Area1*Area2))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
1,705 1.7,18 -= O. V27A-a-Fr
23 .a) > • 39-4C • FF
S/N: C2170550GA87 Talbert & Bright
PondPack Ver: 7.0 (32 5 ) Compute Time: 11:19:02 Date: 08-09-2004

Permit No.
(To be provided by DWO
II. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual
(N.C. Department of Environment, Health, and Natural Resources, November, 1995) and Administrative
Section 15A NCAC 2H.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 written
justification.
Please initial in the blinks prior to each requirement.
a. The basin captures the runoff from the 1 year, 24 hour storm and releases it over a period of 48
/ hours
b OR the basin captures the runoff from the 1 inch storm and allows it to draw down over a period
of 2-5 days.
mac. The minimum flow length ratio is 3:1, L:W.
✓d. Basin sideslopes are no steeper than 3:1.
Poll, e. A small permanent pool has been provided at the outlet to reduce clogging. w 1ffi A.! 1019�7-
s r�vGN�
--.,"f. Cleanout access has been provided, sufficient for heavy equipment.
-g.' A.drain has been provided which will completely empty the basin for cleanout.
h. Sufficient volume has been provided for any local government peak flow requirements.
Ai. If the basin was used during construction as a sediment basin or trap, it must be cleaned out to
design spppifications prior to operation as a dry detention basin.
j. A vegetation plan has- been prepared by a N.C. licensed professional. Consideration must be
given to tl p grasses specified due to the frequent inundation.
✓k. The basir6nust be stabilized within 14 days of construction.
1. The design provides for the sediment storage in addition to the detention volume that is equal to
20% of the detention volume.
m. Inlet and outlet channels have been protected from scour during high flows from large storms.
_n. In areas of easily erodiblo soils, an additional plunge pool at the inlet has been provided, or riprap
is used as 'an energy dissipator.
o. A forebay,to capture sediment is recommended to make cleanout easier.
p. The basin;is located in uncompacted natural soils.
q. The seasdal high water table is located at least 1 foot below the bottom of the extended dry
/ detention Basin.
r. An additi ' nal BMP (such as swale r vegetated filter) has been designed to operate in
conjuncti& with this dry deterttiex-casm to meet the required minimum 85% TSS removal.

Permit No.
(To be provided by DWo
III. EXTENDED DRY DETENTION OPERATION AND MAINTENANCE AGREEMENT
j
The extended dry detention system is defined as the dry detention basin, forebay, and the required additional
BMP.
This system (check oke) ❑ does ❑ does not incorporate a vegetated filter.
This system check one) ❑ does ❑ does not incorporate non-integrated pretreatment.
Maintenance activities shall be performed as follows:
1. All grassed areas of the basin shall be mowed at least twice annually, more frequently as needed.
2. Debris must be removed from the basin, outlet and orifice whenever it accumulates or at least twice
annually.
3. Annually- inspect the basin after a rain event to ensure it is functioning properly.
4. Repair any erosjon of the side slopes and around the inlets and outlet immediately.
T;
5. Accumulated sgdiment shall removed if it has reduced the available volume to 75% of the original
depth. ,
X
6. The emergencyspillway shall be kept in good working order.
7. Woody vegetatipn shall be removed from the banks.
8. Any areas of the system found to be deficient shall be repaired or replaced to design standards.
9. Written records of the inspections and maintenance activities shall be kept on file.
I acknowledge and agree by my signature below that I am responsible for the performance of the above
maintenance procedures for the dry detention basin. I agree to notify DWQ of any problems with the system
or changes in the name of the project, responsible party, or address.
Print name:- :i Title:
Address:
Phone: Fax:
Signature: Date:
a Notary Public for the State of
County of
do hereby certify that personally appeared before me this
the day of , and acknowledge the due execution
of the forgoing dry detention basin maintenance requirements. Witness my hand and official seal,
SEAL
Signature
I
My Commission expics
i

Permit No.
(To be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
EXTENDED DRY DETENTION BASIN SUPPLEMENT
This form may be photocopied for use as an original.
DWO Stormwater Management Plan Review:
A complete stormwater management an submittal includes a dry detention basin supplement for each basin,
design calculations, plans and specification showing all basin and outlet structure details, and a fully executed
operation and maintenance agreement.
M4VK POW
JOLIC WILSEY 3tf1-'f333
Contact Person: {j2I L Tv ,,4 i0H Phone Number:_:I &3 5 as 0
Msaq
For projects with multiple basins, specify which basin this worksheet applies. to: C tiJ
Design Storm: (Please mark one) ❑ 1 yr, 24 hr storm �f 1" storm tea' 1�A J>1.
t
Drainage Area: 32-Ac- sweet
Required Volume: 41 3(O AG. Ff Gubie-feet
I. PROJECT INFORMATION (Please complete the following information):
Project Name: W tL-M (AJ47-bIJ /tit7EW-A*--7onr 4L Ap-r a
�.
Built -upon Area: & 5 % �
SHWT elevation: 6o FMSL
Basin Dimensions: r C-o w rL-o A3 0-0 Awlit-L, 1 N Vev T- q, 8
Bottom Elevation: 10 feet, MSL Area: /000 ft long x �(J ft wide = % �f a 0 Q ft2
Storage Elevation: Z, Z feet, MSL Area: d 2-oo ft long x 5-00 " ft wider--- !j9,9 f 9 ft2
Detention Volume Provided: 7 , U 10
Sediment Storage Provided: 3,10 meet (Equivalent to 20% of the detention volume)
Sediment Storage Elevation: I b 0 FMSL
7a
3 Sl �f ✓
Drawdown Orifice: 1 "Di ��-� iN(Please indicate size and type of orifice)
Required Additional $MP to achieve a total of 85% TSS (check one):
l(Grassed swale -❑Vegetated Filter ❑ Other
/216�'z10� f- �2a d) ars S 7 ZsY R°< ,¢ eels', i X i

Type.... Vol: Elev-Area Page 1.01
Name.... P 20
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 2 SOLUTION SOUTH.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
------------------------------------------------------------------------
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
7.00
----- 0
0
.000
.000
8.00
----- 7000
7000
.054
.054
9.00
----- 16000
33583
.257
.311
10.00
----- 116170
175283
1.341
1.652
10.70
----- 304037
608143
3.258
4.909
10.80
----- 330780
951944
.728
5.638
11.00
----- 382445
1068901
1.636
7.274
12.00
----- 591733
1449894
11.095
18.369
13.00
----- 627496
1828581
13.993
32.36 p
14.00
----- 649276
1915065
14.655
Lv
47.016
15:00
----- 671114
1980495
15.155
62.172
16.00
----- 693012
2046101
15.657
77.829
17.00
----- 714967
2111883
16.161
93.990
18.00
----- 736982
2177840
16.665
110.655
19.00
----- 759054
2243973
17.172
127.827
20.00
----- 781186.
2310281
17.679
145.505
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-ELi) * (Areal + Area2 + sq.rt.(Areal*Area2))
where: ELi, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for ELi, EL2, respectively
Volume = Incremental volume between EL1 and EL2
F L L- P (2 0 (1- (�
seDt -tA Ft-jr Pits.
S/N: C21705506A87 Talbert & "right
PondPack Ver: 7.0 (325) Compute Time: 17:10:09 Date: 08-23-2004

Type.... Vol: Elev-Area
Name.... P 20
Page 1.01
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 2 SOLUTION SOUTH.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
------------------------------------------------------------------------
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
7.00
----- 0
0
.000
.000
.8.00
----- 7000
7000
.054
.054
9.00
----- 16000
33583
.257
.311
10.00
----- 28000
65166
.499
.809
10.70
----- 40000
101466
.544
1.353
10.80
----- 330780
485807
.372
1.724
11.00
----- 382445
1068901
1.636
3.360
12.00
----- 591733
1449894
'11.095
14.455 �D g
13.00
----- 627496
1828581
13.993
28.448
14.00
----- 649276
1915065
14.655
43.103
15.00
----- 671114
1980495
15.155
58.258
16.00
----- 693012
2046101
15.657
73.915
17.00
----- 714967
2111883
16.161
90.076
18.00
----- 736982
2177840
16.665
106.742
19.00
----- 759054
2243973
17.172
123.913
20.00
----- 781186
2310281
17.679
141.592
POND VOLUME EQUATIONS
* incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Area2))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
x(2,1�e -1��r t�j Ass lam.! OJ a
V0L'a t j r /L- St9LAt
A c- V� (' 00 + '05 T,
V - �35�� (32�4C-)= 17,3� �-F'r
x o�O = S,'ft? FG- F%
'7. 2? Ac. • Frt
�3 .9���.�7��/•dK.
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 17:09:08 Date: 08-23-2004

Type.... Outlet Input Data
Name.... PR 20
Page 6.12
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 2 SOLUTION SOUTH.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID
Structure Type = Orifice -Circular
# of Openings = 3
Invert Elev. = 7.00 ft
Diameter = .4375 ft
Orifice Coeff. _ .632
Structure ID
Structure Type = Culvert -Circular
No. Barrels =
1
Barrel Diameter =
2:00( -ft
Upstream Invert =
15.00
ft
Dnstream Invert =
14.70
ft
Horiz. Length =
100.00
ft
Barrel Length
100.00
ft
Barrel Slope =
.00300
ft/ft
OUTLET CONTROL DATA...
e5b
Mannings n .0150
Ke = .5000 (forward entrance loss)
Kb = .016523 (per ft of full flow)
Kr = .5000 (reverse entrance loss)
HW Convergence = .001 +/- ft
INLET CONTROL DATA...
Equation form =
1
Inlet Control K =
.0078
Inlet Control M
2.0000
Inlet Control c =
.02920
Inlet Control Y =
.7400
T1 ratio (HW/D) =
1.134
T2 ratio (HW/D) =
1.206
Slope Factor =
-.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition, zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 17:27 ft ---> Flow = 15.55 cfs
At T2 Elev = 17.41 ft ---> Flow = 17.77 cfs
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 14:47:22 Date: 08-20-2004

Permit No.
(To be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
J.
.EXTEENDED DRY DETEN T ION BASIN SUPPLEMENT
This form may be photocopied for use as an original.
DWO Stormwater Management Plan Review:
A complete stormwater management p an bmittal includes a dry detention basin supplement for each basin,
design calculations, plans and specification showing all basin and outlet structure details, and a fully executed
operation and maintenance agreement.
L PROJECT INFORMATION (Please complete the following information):
Project Name: %tWit-t-4pJ471N /N?�Y�-N�`70Ngt/ �+2PaELT' 5mak(.
Contact Person:_ ERI L siv KPH Phone Number. -7
H*VK
GX /c�+vci Vr
For projects with multiple basins, specify which basin this worksheet applies. to: DETi a 1.1 g t.J
Design Storm: (Please mark one) 01 yr, 24 hr storm " storm IVp • Z . (Cbb&2_)
Drainage Area: I
g w ` ! T
en"�w�seet- Built -upon Area: &0 Yo P"
(,
Required Volume: , 0 S �c��eet SHWT elevation: l b FMSL
Basin Dimensions: �.0� �-ovj C k4 0Ja, 10V 7-0 , S
K
Bottom Elevation: `i . s feet, MSL Area: /00 0 ft long x IL ft wide = D 0 a o f12
Storage Elevation: 'L3� feet; MSL Area: o ft long x ! YO ft wide='Yl Y,'790 ft2
Detention Volume Provided: S10 9
Sediment Storage Provided: ,GZ eubie-feet (Equivalent to 20% of the detention volume)
Sediment Storage Elevation: 22 / FMSL
Drawdown Orifice: `� � 51/?3tf /�✓ ���o Ko�S
r (Please indicate size and type of orifice)
Required Additional I M to achieve a total of 85% TSS (check one):
t
Efirassed swale Vegetated Filter ❑ Other
N671F► yyrr�fL��'jGE SlZ rJ�f� c.c�•��-rPLtdFlco,�`�/ U.Sr .✓G—P/���.qy��/

Type.... Vol: Elev-Area
Name.... P 30
Page 1.01
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 20 SOLUTION NORTH.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
------------------------------------------------------------------------
(sq.1n) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
20.50
----- 0
0
.000
.000
21.50
----- 10000
10000
.077
.077
22.00
----- 77900
115811
.443
.520
22.20
----- 134795
315167
.482
1.002
22.30
----- 163242
446375
.342
1.344
22.40
----- 191690
5318.27
.407
1.751
22.50
----- 220137
617249
.472
2.223
23.00
----- 372566
879087
3.364
5.586 <-
24.00
----- 478131
1272758
9.740
15.326
25.00
26.00
----- 501649
- --- 525371
1469529
1540393
11.245
11.788
26.571
38.359 %—b
27.00
----- 549292
1611861
12.334
50.693 ll..
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Areal))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
Fv4� VoUvA�e (lBeFisA-e CMl Ke"
ST"Are "KWO d J)
C X TIF" e�D b DCTOJ 700
SASW No,
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 09:54:46 Date: 08-20-2004

Type.... Vol: Elev-Area
Name.... P 30
Page 1.01
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 20 SOLUTION NORTH.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
------------------------------------------------------------------------
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
20.50
----- 0
0
.000
.000
21.50
----- 10000
10000
.077
.077
22.00
----- 14000
35832
.137
.214
22.20
----- 16000
44967
.069
.282
22.30
----- 17000
49492
.038
.320
22.40
` n2.50
----- 18000
52493
.040
.360
----- 220137
301085
.230
.591
23.00
----- 372566
879087
3.364
3.954 1<—
24.00
25.00
----- 478131
----- 501649
1272758
1469529
9.740
11.245
13.694
24.939� Q 2
26.00
----- 525371
1540393
11.788
36.727
27.00
----- 549292
1611861
12.334
49.061
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 +'sq.rt.(Areal*Areal))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
j' h
Q.et�uab �OL"Jmc A- /44,�Xc.
t' c wce N r 5T%O-A,,E
Sr�'o AC' fT``
r► of l A( -,Pr
1
6 o of 0 l VA POLVI 00S
C4a�+ " D S
�4c) _ , o$ .r,
2x°(o b (PS Ac.Pr
5/N: C21705506A.87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 09:58:40 Date: 08-20-2004

Type.... Outlet Input Data
Name.... PR 30
Page 6.04
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\AUGUST 20 SOLUTION NORTH.PPW
OUTLET STRUCTURE INPUT DATA
St,ri '"cture ID
Structure Type = Orifice -Circular
# of Openings = 2
Invert Elev. = 20.50 ft
Diameter = .4271 ft
Orifice Coeff. _ .632
Structure ID
Structure Type = Culvert -Circular
No. Barrels =
1
Barrel Diameter =
2.5000
ft
Upstream Invert =
23.20
ft
Dnstream Invert =
22.50
ft
Horiz. Length =
30.00
ft
Barrel Length =
30.01
ft
Barrel Slope =
.02333
ft/ft
OUTLET CONTROL DATA.
Mannings n .0150
Ke = .2000 (forward entrance loss)
Kb = .012271 (per ft of full flow)
Kr = .5000 (reverse entrance loss)
HW Convergence = .001 +/- ft
INLET CONTROL DATA...
Equation form =
1
Inlet Control K =
.0078
Inlet Control M =
2.0000
Inlet Control c =
.02920
Inlet Control Y =
.7400
T1 ratio (HW/D) =
1.124
T2 ratio (HW/D) =
1.196
Slope Factor =
-.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 26.01 ft ---> Plow = 27.16 cfs
At T2 Elev = 26.19 ft ---> Flow = 31.05 cfs
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 16:32:51 Date: 08-23-2004

Permit No.
(To be provided by DWO
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
EXTENDED DRY DETENTION BASIN SUPPLEMENT
This form may be photocopied for use as an original.
D,WO Stormwater M a ement Plan Review:
A complete stormwater management plan su mittal includes a dry detention basin supplement for each basin,
design calculations, plans and specification showing all basin and outlet structure details, and a fully executed
operation and maintenance agreement.
I. PROJECT INFORMATION (Please complete the following information): Project Name: W ILM PJ4711M ?�YZN�j?ONI 5Tfl2Mt�J YL *$•fi 1 p U4+J
Contact Person: ?��I � � 3 � - `f 333
ZRI C- s v", PH Phone Number: % - S 3 S 0
For projects with multiple basins 6A-61 P �t
Ai
Pr J p ,specify which basin this worksheet applies. to:
Design Storm: (Please mark one) 01 yr, 24 hr storm " storm
Drainage Area: 3S ,,`12 '-sweet
Required Volume: eWbie-f t
Basin Dimensions: L-o W F C-0 W
Bottom Elevation: 0 feet, MSL
Storage Elevation: 23 3 feet, MSL
Built -upon Area: !o S _l4 square -feet
SHWT elevation: (Z FMSL
C#*Nae7— IAIV, ZQ , o
Area: Z70 fi long x —J_ftwide = v J ft2
Area: 931) ft long x 7 a ft wide,--- C S /(A p ft2
Detention Volume Provided: 1,7 q xc-'rr �--
Sediment Storage Provided: or 3s -c eet (Equivalent to 20% of the detention volume)
Sediment Storage Elevation: q/ 4,0 FMS
Drawdown Orifice: (Please indicate size and type of orifice)
Required Additional $MP to achieve a total of 85% TSS (check one):
NJGReJrassed swale ❑Vegetated Filter O Other
�v-
'_ ���� tom- >��?,�U- sue-' �,✓oc,�c, ��E'n-A�)c,

Type.... Outlet Input Data
Name.... PR 20
Page 6.03
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\TERMINAL AREA DRY POND
POSTB.PPW
OUTLET STRUCTURE INPUT DATA
Structure ID =
Structure Type = Orifice- ular
-----------------------
# of Openings = 1
Invert Elev. 20.00 ft
Diameter = .2708 ft
Orifice Coeff. = 632
Structure ID
Structure Type = Weir -Rectangular
------------------------------------
# of Openings = 1
Crest Elev. = 26.60 ft
Weir Length = 18.00 ft
Weir Table File: WEIR TAB.WCT
Weir Table ID: Weir C 10
WEIR COEFFICIENT TABLE
Depth, ft Weir C
.20
2.6900
.40
2.7200
.60
2.7500
.80
2.8500
1.00
2.9800
1.20
3.0800
1.40
3.2000
1.60
3.2800
1.80
3.3100
3.00
3.3200
Weir TW effects (Use adjustment equation)
-D ( SrV2, l &I"v
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 10:55:34 Date: 08-09-2004

Type.... Executive Summary (Nodes) Page 1.01
Name.... Watershed Storm: 1" Eq
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\TERMINAL AREA DRY POND
POSTB.PPW
Storm... TypeIII 24hr Tag: 1" Eq
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm Fiie,ID = NHC.RNQ NHC
Storm Tag Name = 1" Eq tSiyt
Data Type, File, ID = Synthetic Storm SCSTYPES.RNF TypeIII 24hr
Total Rainfall Depth= 1.7700 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
HYG Vol
Qpeak
Qpeak Max WSEL
Node
ID
Type
ac-ft
Trun. hrs
cfs ft
AREA
D1
AREA
.712
- ----------
12.3000
-------- ---------
6.12
AREA
D2
AREA
.313
12.2000
2.96
AREA
D3
AREA
.108
12.3000
.91
AREA
D4
AREA
.243
12.1500
2.54
AREA
D5
AREA
.373
12.2000
3.59
Outfall OUT
10
JCT
1.748
17.3500
.49
P 10
IN POND
1.748
12.2500
15.53
P 10
OUT POND
1.748
17.3500
.49 22.98
(,1 L 9 Inc • r f — (Lt'� U �.T►,►-��' 'Frt- . I ,7"1 �� 2`f - I-t� Rah .
6A UI tj
_ Te I Sim R•vti�f'F fe'L
(ZJ — .009 (T) + . 05
1^ Ca 5 af{o 1-4 PeYL0 qV% --� �� s 0, G 3 S'
0 -2,9 ?A-0- t f--r-
( e 1 FT-
; (0 . 00 R 2 7
A-S
oK,
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 10:55:34 Date: 08-09-2004

Type.... Vol: Elev-Area
Name.... P 10
Page 5.01
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\TERMINAL AREA DRY POND
POSTB.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
-------------------------------------_-----------------------------------
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
20.00
----- 0
0
.000
.000
21.00
----- 2800
2800
.021
.021
22.00
----- 6000
12899
.099
.120
22.10
----- 45278
67760
.052
.172
23.00
----- 62258
160630
1.106
1.278
24.00
----- 71922
201096
1.539
2.817
25:00
----- 78379
225382
1.725
4.542
26.00
----- 84934
244904
1.874
6.416
27.00
----- 91430
264486
2.024
Q(�-yj46U
8.440
28.00
----- 97969
284042
2.174
10.613
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Areal))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
V0L0,#Ae f-C'�)VC43b ZL( SebkAker.
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 10:55:34 Date: 08-09-2004

Type.... Vol: Elev-Area Page 1.01
Name.... P 10 C55.o1 A)
File.... J:\3301 (WILMINGTON)\0305 MASTER DRAINAGE PLAN\TERMINAL AREA DRY POND
POSTB.PPW
Elevation
Planimeter Area
Al+A2+sgr(A1*A2)
Volume
Volume Sum
(ft)
(sq.in) (sq.ft)
(sq.ft)
(ac-ft)
(ac-ft)
20.00
----- 0
-------- --------------------------
0
.000
.000
21.00
----- 2800
2800
.021
.021
22.00
----- 45278
59338
.454
.475
23.00
----- 62258
160630
1.229
1.705
24.00
----- 71922
201096
1.539
3.244
25.00
----- 78379
225382
1.725
4.968
26.00
----- 84934
244904
1.874
6.842
27.00
----- 91430
264486
2.024
8.866
28.00
- - - - - 97969
284042
2.174
11.040 (�tlILO
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Areal))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
F-/ L-tr V o L J
C)('L23.6) >•39-4C•1
= D.Zx 0-+C-p-
S/N: C21705506A87 Talbert & Bright
PondPack Ver: 7.0 (325) Compute Time: 11:19:02 Date: 08-09-2004

Permit No.
(To be provided by DWQ)
H. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual
(N.C. Department of Environment, Health, and Natural Resources, November, 1995) and Administrative
Section 15A NCAC 2H.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 Peneit
Application Form, the iagent may initial below. If a requirement has not been met, attach written
justification.
Please initial in the blanks prior to each requirement.
a. The basin'captures the runoff from the 1 year, 24 hour storm and releases it over a period of 48
hours
✓ b OR the ba§in captures the runoff from the 1 inch storm and allows it to draw down over a period
of 2-5 days.
mac. The minirum flow length ratio is 3:1, L: W.
✓d. Basin sideslopes are no steeper than 3:1.
1/0' e. A small permanent pool has been provided at the outlet to reduce clogging. s �I-
-""'f Cleanout access has been provided, sufficient for heavy equipment.
A.drain has been provided which will completely empty the basin for cleanout.
h. Sufficient volume has been provided for any local governriaent peak flow requirements.
If the basin was used during construction as a sediment basin or trap, it must be cleaned out to
design sp�Cifications prior to operation as a dry detention basin.
I. A vegetation plan has been prepared by a N.C. licensed professional. Consideration must be
given to the grasses specified due to the frequent inundation.
✓k. The basil� inust be stabilized within 14 days of construction.
�✓ I. The design provides for the sediment storage in addition to the detention volume that is equal to
20% of the detention volume.
m. Inlet and outlet channels have been protected from scour during high flows from large stones.
n. In areas of easily erodible, soils, an additional plunge pool at the inlet has been provided, or riprap
is used as 'an energy dissipator.
(J o. A forebay�,to capture sediment is recommended to make cleanout easier.
V. The basinjs located in uncompacted natural soils.
✓ q. The seasofi'al high water table is located at least 1 foot below the bottom of the extended dry
detention Basin.
r. An additional BUT (such as �s�Dzeer vegetated filter) has been designed to operate in
conjunctidh with this dry detsm to meet the required minimum 85% TOSS removal.

Permit No.
(To be provided by DWQ)
ft
III. EXTENDED DRY DETENTION OPERATION AND MAINTENANCE AGREEMENT
A
The extended dry deter tion system is defined as the dry detention basin, forebay, and the required additional
BUT.
This system check ohe) ❑ does ❑ does not incorporate a vegetated filter.
This system (check one) El does ❑ does not incorporate non-integrated pretreatment.
Maintenance activities shall be performed as follows:
1. All grassed areas of the basin shall be mowed at least twice annually, more frequently as needed
2. Debris must be removed from the basin, outlet and orifice whenever it accumulates or at least twice
annually.
3. Annually- inspect the basin after a rain event to ensure it is functioning properly.
4. Repair any erosion of the side slopes and around the inlets and outlet immediately.
T
5. Accumulated sediment shall removed if it has reduced the available volume to 75% of the original
depth.
6. The emergency°spillway shall be kept in good working order.
7. Woody vegeta*n shall be removed from the banks.
8. Any areas of the system found to be deficient shall be repaired or replaced to design standards.
9. Written records of the inspections and maintenance activitics shall be kept on file.
I acknowledge and agree by my signature below that.I am responsible for the performance of the above
maintenance procedures for the dry detention basin. I agree to notify DWQ of any problems with the system
or changes in the name of the project, responsible party, or address.
Print name: ., Title:
Address: y�.
Phone: Fax:
Signature: Date:
a Notary Public for the State of
County of
do hereby certify that personally appeared before me this
the day of , and acknowledge the due execution
of the forgoing dry detention basin maintenance requirements. Witness my hand and official seal,
SEAL,
Signature
My Commission expiivs 771"�
F'i''L!+3
i