SW8021017_Historical File_20030106

Fwarfi -r.�,� Michael F. Easley, Governor
Q
AiWilliam G. Ross, Jr., Secretary
0Y 7 North Carolina Department of Environment and Natural Resources
3T�
Alan W. Klimek, P.E., Director
`c Division of Water Quality
Wilmington Regional Office
January 6, 2003
Mr. Timothy A. Jordan, Vice Chancellor for Business Affairs
UNC Wilmington
601 S. College Road
Wilmington, NC 28403
Subject: Permit No. SW8 021017
UNCW Surface Parking Lot "O"
High Density Stormwater Project
Dear Mr. Jordan:
New Hanover County
The Wilmington Regional Office received a complete Stormwater Management Permit
Application for UNCW Surface Parking Lot "O" on December 19, 2002. Staff review of the
plans and specifications has determined that the project, as proposed, will comply with the
Stormwater Regulations set forth in Title 15A NCAC 2H.1000. We are forwarding Permit No.
SW8 021017 dated January 6, 2003, for the construction of UNCW Surface Parking Lot "O".
This permit shall be effective from the date of issuance until January 6, 2013, and shall be subject
to the conditions and limitations as specified therein. Please pay special attention to the
Operation and Maintenance requirements in this permit. Failure to establish an adequate system
for operation and maintenance of the stormwater management system will result in future
compliance problems.
If any parts, requirements, or limitations contained in this permit are unacceptable, you have the
right to request an adjudicatory hearing upon written request within thirty (30) days following
receipt of this permit. This request must be in the form of a written petition, conforming to
Chapter 150B of the North Carolina General Statutes, and filed with the Office of Administrative
Hearings, P.O. Drawer 27447, Raleigh, NC 27611-7447. Unless such demands are made this
permit shall be final and binding.
If you have any questions, or need additional information concerning this matter, please contact
Linda Lewis, or me at [phone].
Sincerely,
Rick Shiver
Water Quality Regional Supervisor
RSS/arl: S:\WQS\STORMWAT\PERMIT\021017.JAN
cc: Mark Hargrove, P.E.
Tony Roberts, New Hanover County Building Inspections
Beth E. Wetherill, New Hanover County Engineering
Linda Lewis
Wilmington Regional Office
Central Files
A
N.C. Division of Water Quality 127 Cardinal Drive Extension Wilmington, N.C. 28405 [phone] Fax [phone] Customer Service
800-623-7748

State Stormwater Management Systems
Permit No. SW8 021017
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
UNC Wilmington
UNCW Surface Parking Lot "O"
New Hanover County
FOR THE
construction, operation and maintenance of a wet detention pond in compliance with the
provisions of 15A NCAC 2H .1000 (hereafter referred to as the "stormwater rules') and the
approved stormwater management plans and specifications and other supporting data as attached
and on file with and approved by the Division of Water Quality and considered a part of this
permit.
This permit shall be effective from the date of issuance until January 6, 2013, and shall be subject
to the following specified conditions and limitations:
I. DESIGN STANDARDS
1. This permit is effective only with respect to the nature and volume of stormwater
described in the application and other supporting data.
2. This stormwater system has been approved for the management of stormwater runoff as
described on page 3 of this permit, the Project Data Sheet. The stormwater control has
been designed to handle the runoff from 33,303 square feet of impervious area.
3. The tract will be limited to the amount of built -upon area indicated on page 3 of this
permit, and per approved plans.
4. All stormwater collection and treatment systems must be located in either dedicated
common areas or recorded easements. The final plats for the project will be recorded
showing all such required easements, in accordance with the approved plans.
5. The runoff from all built -upon area within the permitted drainage area of this project must
be directed into the permitted stormwater control system. A permit modification must be
submitted and approved prior to the construction of additional built -upon area from
outside of the approved drainage area.
2

State Stormwater Management Systems
Permit No. SW8 021017
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
UNC Wilmington
UNCW Surface Parking Lot "O"
New Hanover County
FOR THE
construction, operation and maintenance of a wet detention pond in compliance with the
provisions of 15A NCAC 2H .1000 (hereafter referred to as the "stormwater rules') and the
approved stormwater management plans and specifications and other supporting data as attached
and on file with and approved by the Division of Water Quality and considered a part of this
permit.
This permit shall be effective from the date of issuance until January 6, 2013, and shall be subject
to the following specified conditions and limitations:
I. DESIGN STANDARDS
1. This permit is effective only with respect to the nature and volume of stormwater
described in the application and other supporting data.
2. This stormwater system has been approved for the management of stormwater runoff as
described on page 3 of this permit, the Project Data Sheet. The stormwater control has
been designed to handle the runoff from 33,303 square feet of impervious area.
3. The tract will be limited to the amount of built -upon area indicated on page 3 of this
permit, and per approved plans.
4. All stormwater collection and treatment systems must be located in either dedicated
common areas or recorded easements. The final plats for the project will be recorded
showing all such required easements, in accordance with the approved plans.
5. The runoff from all built -upon area within the permitted drainage area of this project must
be directed into the permitted stormwater control system. A permit modification must be
submitted and approved prior to the construction of additional built -upon area from
outside of the approved drainage area.
2

State Stormwater Management Systems
Permit No. SW8 021017
DIVISION OF WATER QUALITY
PROJECT DESIGN DATA SHEET
Project Name: UNCW Surface Parking Lot "O"
Permit Number: SW8 021017
Location: New Hanover County
Applicant: Mr. Timothy A. Jordan
Vice Chancellor for Business Affairs
Mailing Address: UNC Wilmington
601 S. College Road
Wilmington, NC 28403
Application Date:
December 19, 2002
River Basin / Receiving Stream:
Cape Fear / UT Bradley Creek
Index #:
CPF24 18-87-24-4-(1)
Classification of Water Body:
"SC HQW #"
Drainage Area, acres:
1.24
Onsite, ftz:
1.24
Offsite, ftz:
0
Total Impervious Surfaces, ftz:
33,303
Pond Depth, feet:
4'
TSS removal efficiency:
90% (no vegetated filter is required)
Permanent Pool Elevation, FMSL:
34
Permitted Surface Area, ftz:
2,940 @Permanent Pool
Permitted Storage Volume, ft3:
2,723
Temporary Storage Elevation, FMSL:
34.81
Controlling Orifice:
0.7511cp pipe (drawdown in 2-5 days)
Permitted Forebay Volume, ft3:
656
3

State Stormwater Management Systems
Permit No. SW8 021017
H. SCHEDULE OF COMPLIANCE
1. The stormwater management system shall be constructed in it's 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. The permittee shall at all times provide the operation and maintenance necessary to assure
the permitted stormwater system functions at optimum efficiency. The approved
Operation and Maintenance Plan must be followed in its entirety and maintenance must
occur at the scheduled intervals including, but not limited to:
a. Semiannual scheduled inspections (every 6 months).
b. Sediment removal.
C. Mowing and revegetation of slopes and the vegetated filter.
d. Immediate repair of eroded areas.
e. Maintenance of all slopes in accordance with approved plans and specifications.
f. Debris removal and unclogging of outlet structure, orifice device, flow spreader,
catch basins and piping.
g. Access to the outlet structure must be available at all times.
4. Records of maintenance activities must be kept and made available upon request to
authorized personnel of DWQ. The records will indicate the date, activity, name of
person performing the work and what actions were taken.
5. Decorative spray fountains will not be allowed in the stonnwater treatment system.
6. The facilities shall be constructed as shown on the approved plans. This permit shall
become voidable unless the facilities are constructed in accordance with the conditions of
this permit, the approved plans and specifications, and other supporting data.
7. Upon completion of construction, prior to issuance of a Certificate of Occupancy, and
prior to operation of this permitted facility, a certification must be received from an
appropriate designer for the system installed certifying that the permitted facility has been
installed in accordance with this permit, the approved plans and specifications, and other
supporting documentation. Any deviations from the approved plans and specifications
must be noted on the Certification. A modification may be required for those deviations.
8. If the stormwater system was used as an Erosion Control device, it must be restored to
design condition prior to operation as a stormwater treatment device, and prior to
occupancy of the facility.
9. The permittee shall submit to the Director and shall have received approval for revised
plans, specifications, and calculations prior to construction, for any modification to the
approved plans, including, but not limited to, those listed below:
a. Any revision to any item shown on the approved plans, including the stormwater
management measures, built -upon area, details, etc.
b. Project name change.
C. Transfer of ownership.
d. Redesign or addition to the approved amount of built -upon area or to the drainage
area.
e. Further subdivision, acquisition, or sale 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.
4

State Stormwater Management Systems
Permit No. SW8 021017
10. The permittee shall submit final site layout and grading plans for any permitted future
areas shown on the approved plans, prior to construction. If the proposed BUA exceeds
the amount permitted under this permit, a modification to the permit must be submitted
and approved 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. Prior to the sale or lease of any portion of the property, the permittee shall notify DWQ
and provide the name, mailing address and phone number of the purchaser or leasee. An
access/maintenance easement to. the stormwater facilities shall be granted in favor of the
permittee if access to the stormwater facilities will be restricted by the sale or lease of any
portion of the property.
13. The permittee must maintain compliance with the proposed built -upon area and ensure
that the runoff from all the built -upon is directed into the permitted system.
14. 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.
15. The permittee must maintain the current permitted drainage area. No additional runoff
from outside of the permitted drainage area boundary may enter the permitted stormwater
facilities without first applying for and receiving a permit modification.
III. GENERAL CONDITIONS
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 transfer 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. The permittee is responsible for compliance with all permit conditions
until such time as the Division approves the transfer request.
2. Failure to abide by the conditions and limitations contained in this permit may subject the
Permittee to enforcement action by the Division of Water Quality, in accordance with
North Carolina General Statute 143-215.6A to 143-215.6C.
3. The issuance of this permit does not preclude the Permittee from complying with any and
all statutes, rules, regulations, or ordinances which may be imposed by other government
agencies (local, state, and federal) 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 perrnittee grants DENTR Staff permission to enter the property during normal business
hours for the purpose of inspecting all components of the permitted stormwater
management facility.
6. The permit may be modified, revoked and reissued or terminated for cause. The filing of
a request for a permit modification, revocation and reissuance or termination does not
stay any permit condition.
61

State Stormwater Management Systems
Permit No. SW8 021017
7. Unless specified elsewhere, permanent seeding requirements for the stormwater control
must follow the guidelines established in the North Carolina Erosion and Sediment
Control Planning and Design Manual.
8. Approved plans and specifications for this project are incorporated by reference and are
enforceable parts of the permiic.
9. The permittee shall notify the Division any name, ownership or mailing address changes
within 30 days.
Permit issued this the 6th day of Janaury, 2003.
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
Alan W. Klimek, P.E., Director
t Division of Water Quality
By Authority of the Environmental Management Commission
T

OFFICE USE ONLY
Da a Received
Fee Paid
Permit Number
�i
11
"i�r-- X 7-5,1
1 W
00�/b 11
State of North Carolina
Department of Environmental and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
This form may be photocopied for use as an original
I. GENERAL INFORMATION
1. Applicants name (specify the name of the corporation, individual, etc. who owns the project):
UNC- Wilmington
2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance):
Timothy A. Jordan, Vice Chancellor Business Affairs
Mailing Address for person listed in Item 2 above:
601 South College Road
City: Wilmington
Telephone Number: ( 910 ) 962-7317
F-11:Ti - 2 6 : � 1
4. Project Name (subdivision, facility, or establishment name — should be consistent with project name on plans,
specifications, letters, operation and maintenance agreements, etc.):
UNCW Surface Parking Lot, Code 49728 Item 30, Parking Lot "O"
5. Location of Project (street address):
Corner of Walton Drive and Riegel Drive
City: Wilmington County: New Hanover
6. Directions to project (from nearest major intersection):
College Street to Randall Parkway to Reynolds Drive, left turn on Price Drive to intersection with Walton
Drive, right turn on Walton to intersection of Riegel Road, NW corner.
7. Latitude:. 34 - 13 Longitude: 77 - 52 of project.
8. Contact person who can answer questions about the project::
Name: Mark Hargrove, PE Telephone Number: ( 910 ) 762-4200 x250
H. PERMIT INFORMATION:
Specify whether project is (check one): X New Renewal Modification
Form SWU-101 Version 3.99 Page 1 of 4

2. If this application is being submitted as the result of a renewal or modification to an existing permit, list the
existing permit number and its issue date (if known)
3. Specify the type of project (check one):
Low Density X High Density Redevelop General Permit Other
4. Additional Project Requirements (6[ie.c_.k applicable blanks)):
CAMA Major X Sedimentation/Erosion Control 404/401 Permit NPDES Stormwater
Information on required state permits can be obtained by contacting the Customer Service Center at
1-877-623-6748
III. PROJECT INFORMATION
1. In the space provided below, summarize how stormwater will be treated. Also attach a detailed narrative
(one to two pages) describing stormwater management for the project.
Wet detention pond designed for 90% TSS treatment
2. Stormwater runoff from this project drains to the Cape Fear
3. Total Project Area: 1.24 acres.
4. Project Built Upon Area: 61.9 %.
5. How many drainage areas does the project have? 1
River Basin.
6. Complete the following information for each drainage area. If there are more than two drainage areas in the
project, attach and additional sheet with the information for each area provided in the same format as below.
Basin Information
Drainage Area 1
Drainage Area 2
Receiving Stream Name
Bradley Creek Tributary
Receiving Stream Class
SC
Drainage Area
53,828 sf — 1.24 acres
Existing Impervious*Area
NA
Proposed Impervious* Area
33,303 SF
% Impervious* Area (Total)
61.9%
Impervious* Surface Area
Drainage Area 1
Drainage Area 2
On -Site Buildings
NA
On -Site Streets
NA
On -Site Parking
32,333 SF
On -Site Sidewalks
970 SF
Other On -Site
NA
Off -Site
NA
Total: 33,303 SF
Total:
*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 2 of 4

7. How was the off -site impervious area listed above derived? NA
IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS
The. following italicized deed restrictions and protective covenants are required to be recorded for all
subdivisions, out parcels, 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.
The following covenants are intended to ensure ongoing compliance with state stormwater management
permit number NA as issued by the Division of Water Quality. These covenants may not
be changed or deleted without the consent of the State.
2. No more than 33,303 square feet of TOTAL lot shall be covered by structures or impervious
materials. Impervious materials include asphalt, gravel, concrete, brick, stone, slate or similar material but
not include wood decking or the water surface of swimming pools.
3. Swales shall not be filled in, piped, or altered except as necessary 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. Allpermitted runofffrom the outparcels or -future 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 [phone] for
the status and availability of these forms.
Form SWU-102
Wet Detention Basin Supplement
Form SWU-103
Infiltration Basin Supplement
Form SWU-104
Low Density Supplement
Form SWU-105
Curb Outlet System Supplement
Form SWU-106
Off -Site System Supplement
Form SWU-107
Underground Infiltration Trench Supplement
Form SWU-108
Neuse River Basin Supplement
Form SWU-109
Innovative Best Management Practice Supplement
Form SWU-101 Version 3.99 Page 3 of 4

VI. SUBMITTAL REQUIREMENTS
Only complete application packages will be accepted and reviewed by the Division of Water Quality (DWQ). A
complete package includes all of the items listed below. The complete application package should be submitted to
the appropriate DWQ Regional Office.
1. Please indicate that you have provided the following required information by initialing in the space provided
next to eaeb item,
Initials
• Original and one copy of the Stormwater Management Permit Application Form ANX
• One copy of the applicable Supplement Form(s) for each BUT fix to
• Permit application processing fee of $420 (payable to NCDENR) M N w.
• Detailed narrative description of stormwater treatment/management 1AJU
• Two copies of plans and specifications, including: /^row
- 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)
VH. 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): Mark Hargrove,P.E. WK Dickson
Mailing Address: 909 Market Street
City Wilmington
Phone: [phone] x250
State: NC
VIII. APPLICANT'S CERTIFICATION
Zip: 28401
Fax: (910 ) 762-4201
I, Timothy A. Jordan, Vice Chancelllor Business Affairs — UNC-Wilmington
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.
Signa Date: Qn�
Form SWU-101 Verson 3.99 Page 4 of 4

Margaret Gray 2010 2-11 (t+)
From: Mark Hargrove
Sent: Wednesday, December 18, 2002 2:58 PM
To: Margaret Gray
Subject: FW: UNCW Surface Parking Lot "O"
RECEIVED
-----Original Message----- DEC 19 2002
From: Linda Lewis [mailto:[e-mail]]
Sent: Tuesday, December 17, 2002 5:31 PM
To: Mark Hargrove
Subject: UNCW Surface Parking Lot "0"
Mark:
Even though the variation is small, I've got three different storage
pool elevations:
34.74 reported on supplement _
34.81 used in calculations
34.78 used on plan details.
Please pick one and submit the necessary revised items.
Linda" . €
W\ er,
IV
pt�t, c�
l�-r,) 1 S
.BW,LJ'C` S'}iFT a.
12hb/01,
1

RE: UNCW Surface Parking Lot "O"
Subject: RE: UNCW Surface Parking Lot "O"
Date: Tue, 17 Dec 2002 17:29:02 -0500
From: "Mark Hargrove" <[e-mail]>
To: "Linda Lewis" <[e-mail]>
Sorry....I will yet it straightened oui..
Thanks for the heads up
Mark
-----Original Message ----
From: Linda Lewis [mailto:[e-mail]]
Sent: Tuesday, December 17, 2002 5:31 PM
To: Mark Hargrove
Subject: UNCW Surface Parking Lot "O"
Mark:
Even though the variation is small, I've got three different storage
pool elevations:
34.74 reported on supplement
34.81 used in calculations
34.78 used on plan details.
Please pick one and submit the necessary revised items.
Linda
1 of 1 12/17/2002 5:55 PM

I&M�.VV K
909 Market Street
Wilmington, NC 28401
910.762.4200 0 FAX: [phone]
TO: NCDENR
Division of Water Quality
ATTENTION: Linda Lewis
�_ AJa $o/o17
LE E ' O :V-1)1WN-' TTAL
CT 14 ZOOZ
DATE:Oct. 14 2002 J ..20102.71.WL
RE: UNC Surface Parking Lot"0"
Riegel Road & Walton Drive
New Hanover County
Stormwater Permit Submittal ,R
We are sending via:
Overnight Regular Mail 0 Pick-up Hand Delivered
The following items:
0 Correspondence Plans E-1 Specifications Fx Other as listed below:
COPIES
DATE
NO.
DESCRIPTION
2 sets
Stormwater Permit Application (8/22/02), Wet Detention Supplement (9/25102)
2 sets
10/7/02
Stormwater Calculations
2 sets
10/8/02
Sheets 1, 2, 3, 4, & 5
1
7/1702
$420.00 application fee (check #23975)
THESE ARE TRANSMITTED as checked below:
Bx For Approval e As requested R
Approved as submitted Returned for corrections
For your use For review and commentApproved as noted Forward to subcontractor
REMARKS:
Linda please advise should you need anything else. Thanks!
COPY TO: Steve Weitnauer w-enc/UNCJV, file SIGNED:

W.K. DICKSON & CO., INC.
23975
Invoice Number
Date
Voucher
Amount
Discounts
Previous Pay
Net Amount
LotO-SW Permit
7/5/02
0046568
420.00
420.00
DENR
Totals
420.00
420.00
2
2 4

STORMWATER CALCULATIONS
UNCW SURFACE PARKING LOT "O"
NEW HANOVER COUNTY
NORTH CAROLINA
RECEIVED
OCT 14 2002
DI
PRoa # ==z- vl
ENGINEERS
WK DICKSON & CO., INC.
909 MARKET STREET
WILMINGTON, N.C. 28401
(910) 7624200
WKD Project #: 20102.71.WL
September, 2002

DRAINAGE NARRATIVE
UNCW SURFACE PARKING LOT "O"
WALTON DRIVE AND RIEGEL ROAD
(20102.71. WL)
GENERAL
The site is located at corner of Walton Drive and Riegel Road and is sparsely
wooded. There is an existing parking lot to the north of the proposed site. The
existing parking will be integrated with the new parking lot layout. The geographical
relief varies from elevation 34 to elevation 41 with an average slope of
approximately 2.5%. The site is currently drained by sheet flow from south to north.
The Soil Conservation Service characterizes soils as Murville fine sand and Seagate
fine sand.
PROPOSED IMPROVEMENTS
Proposed improvements will include the construction of a 82-car parking lot.
Landscaped islands and tree preservation has been maximized to the extent possible
based on the proposed grades and site improvements. Storm drainage will be
collected via a piped collection system and directed to a wet detention pond for
stormwater treatment.
DRAINAGE CONSIDERATIONS
Stormwater runoff will be conveyed to the detention system by means of a drop
inlet -piped system. The wet detention pond will be designed for treatment of 90%
total suspended solids. A forebay and vegetated littoral shelf will be provided in
accordance with state requirements. The outlet structure will be designed with an
orifice size to accommodate the appropriate draw down time. The discharge outlet
for the wet detention pond will be to a nearby ditch, which is an unnamed tributary
to Bradley Creek.

WK DICKSON
Engineering 909 Market Street
Land Planning Wilmington; NC 28401
Surveying [phone]
UNCW PARKING LOT "O"
TOTAL AREA DRAINING TO POND = 53,828 SF =1.24 AC
TOTAL PROPOSED IMPERVIOUS SURFACE AREA DRAINING TO POND:
PAVED AREAS = 32,333 SF
SIDEWALK = 970 SF
BUILDING = 0 SF
33,303 SF
PERCENT IMPERVIOUS DRAINAGE AREA FOR POND:
= (33,303 SF / 53,828 SF) x 100
= 61.9%
REQUIRED STORAGE FOR 1-INCH OF RUNOFF FOR POND: (use Schueler Method)
= 0.05 + 0.009 (I)
= 0.05 + 0.009(61.9) = 0.607
= (1")(0.607)(1/12)(53,828)
= 2,723 CF (2,723 CF PROVIDED)
POND DEPTH SA/DA %
(FT)
4.0 5.43
POND SURFACE AREA (MIN.)
(SF)
IF POND DEPTH = 4.0 FT, MINIMUM SURFACE AREA = 2,923 SF
USED 90% TSS CHART TO SIZE POND
AREA @ ELEVATION 34.00 = 2,940 SF > 2,923 SF
2,923
REQUIRED STORAGE FOR FOREBAY: 20% OF TOTAL PERMANENT POOL VOLUME
= (0.2)(3,027 CF)
= 605 CF (656 CF PROVIDED).
PROJECT: LTNCW PARKING LOT "O" SUBJECT: POND CALCULATIONS JOB NO.: 20102.71.WL
PREPARED BY: RPB DATE: 9/17/02 CHECKED BY: MNH DATE: PAGE NO OF

Engineering
Land Planning
Surveying
WK DICKSON
909 Market Street
Wilmington, NC 28401
[phone]
Pond Volume
Contour
Incremental
Cumulative
Elevation
Area
Volume .
Volume
(ft)
(sf)
(cf)
(cf)
Bottom Elevation 30
.21
0
0
31
192
107
107
32
501
347
453
33
1180
841
1294
Permanent Pool 34
2286
1733
3027
Forebay Volume
Contour
Incremental
Cumulative
Elevation
Area
Volume
Volume
(ft)
A
(cf)
(cf)
Bottom Elevation 32
70
0
0
33
294
182
182
Permanent Pool 34
654
474
656
Forebay Volume is
21.7%
of Pond Volume
PROJECT: UNCW PARKING LOT "O" SUBJECT: POND CALCULATIONS JOB NO.: 20102.71.WL
PREPARED BY: RPB DATE: 9/17/02 CHECKED BY: MNH DATE: PAGE NO OF

Engineering
Land Planning
Surveying
WK DICKSON
909 Market Street
Wilmington, NC 28401
[phone]
POND RELEASE
TIME FOR CONTROL PIPE: POND
ELEV.
EFF. STORAGE
VOL. RELEASED
OUTFLOW RATE
RELEASE TIME
(FT)
(CF)
(CF)
(CFS)
(HOURS)
34.81
ti 2,723
750
0.013
15.7
34.60
1,973
697
0.011
16.9
34.40
1,276
648
0.009
19.3
34.20
628
628
0.007
26.4
34.00
0
TOTAL HOURS
78.3
DAYS
3.3
CONTROL PIPE:
0.75
INCH ORIFICE HOLES
USED ORIFICE EQUATION TO DETERMINE
OUTFLOW RATE
Q = Cd`A"(2gh)"1/2
PROJECT: UNCW PARKING LOT "O" SUBJECT: POND CALCULATIONS JOB NO.: 20102.71.WL
PREPARED BY: RPB DATE: 9/17/02 CHECIKED BY: MNH DATE: PAGE NO OF

WK DICKSON
Engineering 909 Market Street
Land Planning Wilmington, NC 28401
Surveying [phone]
1" Pond Volume
Contour
Incremental
Cumulative
Elevation
Area
Volume
Volume
P�
(ft)
(Sfl
M
(cfl
efm-BevatI n
34.00
2940
0
0
34.20
3211
615
615
34.40
3394
660
1276
P12
34.60
3580
697
1973
Pgrmafter* Poot
34.81
3778
750
2723
PROJECT: UNCW PARKING LOT "O" SUBJECT: POND CALCULATIONS JOB NO.: 20102.71.WL
PREPARED BY: RPB DATE: 9/17/02 CHECKED BY: MNH DATE: PAGE NO OF

153
0
N
O
N
I,-
-7
0)
0
CM
LL
Q
2
LL
N
a
E
m
cn
N
LL
0
z
t5
c.5
S)
0
a

c�
IL
c
O
�
�
�
�
m
1�-
�
�
�
�
cn
E
LM
O
-W
cn
�
0
4-
m
L-
M
�
x
g
§
�
a
_ n
§
»
£
E q 2
CD
§
d K M
ix
cc
C
� £
q § E
�
c £
2 § §
kto k
�
-
E
S 8 .
n
k k k .
B
£
o £
$ Lq � -
\
w
q co )
f
2
% % @ .
k
R ) d
®
-
/
% S S
£
E
o d d
r
n.
k
2 2 L .
)
§
.
)
§ § §
D
5
v)
Lq �
-§ a
U $.q.
L
)
c a
w-
g
a
'a
■.
0) q -
R
ƒ
\
a
L
\
c
£ \
.
6 2 2
2
.
2
12
U.
k
¥
I k
o 0 0
d d
§
e
L6
-
2
co
§ § -
X
t
K
\
{
q qDo
/
d o ci
04
%% E
I .
+
o d d
o
k_
\
�
§ § §
ƒ
�
.
g CD�
2
G
§
E
k 6
ƒ
_3
/
hi
-
"a)
§
§
I _
)
a .
k
©
iL
§
z