SW8080317_HISTORICAL FILE_20080624

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW8 0 2 031"1
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
HISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
/Ooy
YYYYMMDD

\OF wA'Fq
O�
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Randy Blanton, Owner
PO Box 10137
Wilmington, NC 28404
June 24. 2008
Michael F Easley, Governor
William G Ross lr , Secretary
North Carolina Department of Environment and Natural Resources
Subject: State Stormwater Permit No. SW8 080317
Covil Gardens
High Density Commercial Wet Pond Project
New Hanover County
Dear Mr. Blanton:
Coleco H Sullins Director
Division of Water Quality
The Wilmington Regional Office received a complete State Stormwater Management Permit
Application for Covil Gardens on June 23, 2008. Staff review of the plans and specifications
has determined that the project, as proposed, will comply with the Stormwater Regulations set
forth in Session Law 2006-246 and Title 15A NCAC 2H.1000. We are forwarding Permit No.
SW8 080317 dated June 24, 2008 for the construction of the subject project.
This permit shall be effective from the date of issuance until June 24, 2018, 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 sixty (60) 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 Steve Pusey, or me at [phone].
Sincer
Edward Beck
Regional Supervisor
Surface Water Protection Section
ENB/ sgp: S:\WQS\STORMWATER\PERMIT\080317.jun08
cc: Charles Cazier, PE, Tripp Engineering, PC
New Hanover County Building Inspections
City of Wilmington Development Services
Beth E. Wetherill, New Hanover County Engineering
Steve Pusey
EW ilmington.Regiona l=Offices
Central Files
Nor`ihCarolina
Aatura//y
North Carolina Division of Water Quality 127 Cardinal Dnve Extension Wilmington, NC 28405 Phone [phone]
Wilmington Regional Office Internet. www ncwate,qualityo¢ Fax [phone]
An Equal Oppodunity/Affirmative Action Employer- 50 % Recycled110% Post Consumer Paper
Customer Service
1-877-623-6748

State Stormwater Management Systems
Permit No. SW8 080317
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
Randy Blanton, Owner
Covil Gardens
115 Covil Avenue, Wilmington, New Hanover County
FOR THE
construction, operation and maintenance of a wet detention pond in compliance with
the provisions of Session Law 2006-246 and 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 June 24, 2018, and shall
be subject to the following specified conditions and limitations:
I. DESIGN STANDARDS
1. This permit is effective only with respect to the nature and volume of stormwater
described in the application and other supporting data.
2. This stormwater system has been approved for the management of stormwater
runoff as described in Section 1.7 on page 3 of this permit. The stormwater
control has been designed to handle the runoff from 50,928 square feet of
impervious area.
3. The tract will be limited to the amount of built -upon area indicated in Section 1.7
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.
6. The built -upon areas associated with this project shall be located at least 30 feet
landward of all perennial and intermittent surface waters.
Page 2 of 7

State Stormwater Management Systems
Permit No. SW8 080317
The following design criteria have been provided in the wet detention pond and
must be maintained at design condition:
a. Drainage Area, acres:
Onsite, ft :
Offsite, ft2:
b. Total Impervious Surfaces, acres:
Onsite, ft
Offsite, ftz:
C. Design Storm, inches:
d. Average Pond Depth, feet:
e. TSS removal efficiency:
f. Permanent Pool Elevation, FMS�:
g. Permanent Pool Surface Areq, ft
h. Permitted Storage Volume, ft :
i. Temporary Storage Elevation, FMS�:
j. Pre -development flow -1 yr, 24 hr (ft /s):
k. Post -development flow -1 yr, 24 hr (ft%):
I. Controlling Orifice:
M. Permitted Forebay Volume, ft3:
n. Fountain Horsepower, HP
o. Receiving Stream/River Basin:
P. Stream Index Number:
q. Classification of Water Body:
II. SCHEDULE OF COMPLIANCE
9
1.93
84,076
0
1.17
50,928
0
1.5
5
90%
29.0
3,992
9,516at temporary pool elev.
31.0
2.7
0.86
1"OJ pipe
3,426
NA
Burnt Mill Creek / Cape Fear
18-74-63-2
"C; Sw"
The stormwater management system shall be constructed in its entirety,
vegetated and operational for its intended use prior to the construction of any
built -upon surface.
During construction, erosion shall be kept to a minimum and any eroded areas of
the system will be repaired immediately.
The permittee shall at all time 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. Mowin.Q and re -vegetation of slopes and the vegetated filter strip.
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, level
spreader, filter strip, catch basins and piping.
g. Access to the outlet structure must be available at all times.
Records of maintenance activities must be kept for each permitted BMP. The
records will indicate the date, activity, name of person performing the work and
what actions were taken.
The permittee shall submit to the Division of Water Quality an annual summary
report of the maintenance inspection records for each BMP. The report shall
summarize the inspection dates, results of the inspections, and the maintenance
work performed at each inspection.
Page 3 of 7

State Stormwater Management Systems
Permit No. SW8 080317
6. Access to the stormwater facilities shall be maintained via appropriate
easements at all times.
7. The facilities shall be constructed as shown on the approved plans. This permit
shall become void unless the facilities are constructed in accordance with the
conditions of this permit, the approved plans and specifications, and other
supporting data.
8. 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.
9. 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.
10. The permittee shall submit to the Director and shall have received approval for
revised plans, specifications, and calculations prior to construction, for any
modification to the approved plans, including, but not limited to, those listed
below:
a. Any revision to any item shown on the approved plans, including the
stormwater management measures, built -upon area, details, etc.
b. Project name change.
C. Transfer of ownership.
d. Redesign or addition to the approved amount of built -upon area or to the
drainage area.
e. Further subdivision, acquisition, lease or sale of all or part of the project
area. The project area is defined as all property owned by the permittee,
for which Sedimentation and Erosion Control Plan approval or a CAMA
Major permit was sought.
f. Filling in, altering, or piping of any vegetative conveyance shown on the
approved plan.
11. 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.
12. The permittee shall submit final site layout and grading plans for any permitted
future areas shown on the approved plans, prior to construction.
13. 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.
Page 4 of 7

State Stormwater Management Systems
Permit No. SW8 080317
III. GENERAL CONDITIONS
This permit is not transferable except after notice to and approval by the Director.
In the event of a change of ownership, or a name change, the permittee must
submit a completed Name/Ownership Change form, to the Division of Water
Quality, signed by both parties, and accompanied by supporting documentation
as listed on page 2 of the form. The project must be in good standing with the
Division. The approval of this request will be considered on its merits and may or
may not be approved.
2. The permittee is responsible for compliance with all permit conditions until such
time as the Division approves the transfer request.
3. 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.
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 DENR Staff permission to enter the property during normal
business hours for the purpose of inspecting all components of the permitted
stormwater management facility.
7. The permit issued shall continue in force and effect until revoked or terminated.
The permit may be modified, revoked and reissued or terminated for cause. The
filing of a request for a permit modification, revocation and re -issuance or
termination does not stay any permit condition.
8. 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.
9. Approved plans and specifications for this project are incorporated by reference
and are enforceable parts of the permit.
10. The issuance of this permit does not prohibit the Director from reopening and
modifying the permit, revoking and reissuing the permit, or terminating the permit
as allowed by the laws, rules and regulations contained in Session Law 2006-
246, Title 15A NCAC 21-1.1000, and NCGS 143-215.1 et.al.
11. The permittee shall notify the Division of any name, ownership or mailing
address changes at least 30 days prior to making such changes.
Permit issued this the 24th day of June, 2008.
NORT AROLINA VIRONMENTAL MANAGEMENT COMMISSION
for en . Sullins, Director
Division of Water Quality
By Authority of the Environmental Management Commission
Page 5 of 7

D W Q USE ONLY
Date Received
Fee Paid
Permit Number
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
This form may be photocopied for use as an original
I.. GENERAL INFORMATION
1. Applicants name (specify the name of the corporation, individual, etc. who owns the project):
2. Print Owner/Signing Official's name and title (person legally responsible for facility and compliance):
Randy lanton Owner
3. Mailing Address for person listed in item 2 above:
City:Wdmington State:NC Zip:28404
Phone: (910 ) 270-1978 Fax: (910 ) 2704683
Email:
4. Project Name (subdivision, facility, or establishment name - should be consistent with project name on plans,
specifications, letters, operation and maintenance agreements, etc.):
5. Location of Project (street address):
City:Wilmington County:New Hanover
6. Directions to project (from nearest major intersection):
from the intersection of S. Kerr Ave and US 17 travel 0.85 mile west turn left on Covil Ave approximately
7. Latitude:N 34 14' 11" Longitude:W 77 54' 15" of project
8. Contact person who can answer questions about the project:
Name:Charles Cazier Telephone Number: (910 ) 763-5100
Email: trippeneec. rr. com
H. PERMIT INFORMATION:
1. Specify whether project is (check one): ®New ❑Renewal �' i iqy, ,
MAR: 9 6 1UU8 js;A.1
FormSWU-101 Version 8.07 Pagel of4

2. If this application is being submitted as the result of a renewal or modification to an existing permit, list the
existing permit numberNA and its issue date (if known)
3. Specify the type of project (check one):
❑Low Density ®High Density ❑Redevelop ❑General Permit ❑Universal SMP ❑Other
4. Additional Project Requirements (check applicable blanks)
❑CAMA Major ®Sedimentation/Erosion Control 0404/401 Permit KNPDES Stormwater
Information on required state permits can be obtained by contacting the Customer Service Center at
1-877-623-6748.
❑I. 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 basin sized for 1 5" 1-year 2*-hour pre -post state requirements
2. Stormwater runoff from this project drains to the Cape Fear River basin.
3. Total Site Area: 2.22 acres 4. Total Wetlands Area: 0.29 acres
5. 100' Wide Strip of Wetland Area: NA acres (not applicable if no wetlands exist on site)
6. Total Project Area**:1.93 acres 7. Project Built Upon Area:5�-86 1y0' (v
8. How many drainage areas does the project have?1
9. Complete the following information for each drainage area. If there are more than two drainage areas in the
project, attach an additional sheet with the information for each area provided in the same format as below.
Basin Information
Drainage Area 1
Drainage Area 2
Receiving Stream Name
Burnt Mill Creek
Stream Class & Index No.
C-SW / I fi 7q 63 2
Drainage Area (so
84,076 sf
Existing Impervious* Area (so
-
Proposed Impervious*Area (so
50,928 sf
% Impervious* Area (total)
60.6%
Impervious* Surface Area
Drainage Area 1
Drainage Area 2
On -site Buildings (so
17,648 sf
On -site Streets (so
_
On -site Parking (so
28,075 sf
On -site Sidewalks (so
5,205 sf
Other on -site (so
-
Off -site (so
_
Total (so:
50,928 sf
Impervious area is defined as the built upon area including, but not limited to, buildings, roads, parking areas,
sidewalks, gravel areas, etc.
**Total project area shall be calculated based on the current policy regarding inclusion of wetlands in the built upon area
percentage calculation.
Form SWU-101 Version 8.07 Page 2 of 4

10. How was the off -site impervious area listed above derived?NA
IV. DEED RESTRICTIONS AND PROTECTIVE COVENANTS
One of the following deed restrictions and protective covenants are required to be recorded for all subdivisions,
outparcels and future development prior to the sale of any lot. If lot sizes vary significantly, a table listing each lot
number, size and the allowable built -upon area for each lot must be provided as an attachment.
Form DRPC-1
High Density Commercial Subdivisions
Form DRPC-2
High Density Developments with Outparcels
Form DRPC-3
High Density Residential Subdivisions
Form DRPC-4
Low Density Commercial Subdivisions
Form DRPC-5
Low Density Residential Subdivisions
Form DRPC-6
Low Density Residential Subdivisions with Curb Outlets
By your signature below, you certify that the recorded deed restrictions and protective covenants for this
project shall include all the applicable items required in the above form, 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 SW401-Low Density Low Density Supplement
Form SW401-Curb Outlet System Curb Outlet System Supplement
Form SW401-Off-Site System Off -Site System Supplement
Form SW401-Wet Detention Basin Wet Detention Basin Supplement
Form SW401-Infiltration Basin Infiltration Basin Supplement
Form SW401-Infiltration Trench Underground Infiltration Trench Supplement
Form SW401-Bioretention Cell Bioretention Cell Supplement
Form SW401-1-evel Spreader Level Spreader/Filter Strip/Restored Riparian Buffer Supplement
Form SW401-Wetland Constructed Wetland Supplement
Form SW401-Grassed Swale Grassed Swale Supplement
Form SW401-Sand Filter Sand Filter Supplement
Form SWU-101 Version 8.07 Page 3 of

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 Office. (Appropriate office may be found by locating project on the
interactive online map at http'//h2o enr state nc.us/su/msi maps.htm)
1. Please indicate that you have provided the following required information by initiating in the space provided
next to each item.
Initials
• Original and one copy of the Stormwater Management Permit Application Form l✓�
• Original and one copy of the Deed Restrictions & Protective Covenants Form Ord
• Original of the applicable Supplement Form(s) and O&M agreement(s) for each BMP
• Permit application processing fee of $505 ($4,000 for Express) payable to NCDENR
• Calculations & detailed narrative description of stormwater treatment/management
• Copy of any applicable soil report
• Three copies of plans and specifications (sealed, signed & dated), including:
- Development/Project name
- Engineer and firm
-Legend
- North arrow
- Scale
- Revision number & date
- Mean high water line
- Dimensioned property/project boundary
- Location map with named streets or NCSR numbers
- Original contours, proposed contours, spot elevations, finished floor elevations
- Details of roads, drainage features, collection systems, and stormwater control measures
- Wetlands delineated, or a note on plans that none exist
- Existing drainage (including off -site), drainage easements, pipe sizes, runoff calculations
- Drainage areas delineated
- Vegetated buffers (where required)
VII. AGENT AUTHORIZATION
If you wish to designate authority to another individual or firm so that they may provide information on your
behalf, please complete this section.
Designated agent (individual or firm):Tripp Engineering
Mailing Address:419 Chestnut street
City:Wilmington State:NC Zip:28401
Phone: (910 ) 763-5100 Fax: (910 ) 763-5631
Email:[e-mail]
Vill. APPLICANT'S CERTIFICATION
I, (print or type name of person listed in General Infornmtion, item 2) Randy Blanton
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 covenanlslyVill be recorded, and that the proposed project complies with the requirements of 15A
NCAC 21-1.1000.
Signature: ) Date: 11-30-0Z4
Form SWU-101 Version 8.07 Page 4 of

TRIPP ENGINEERING, P.C.
0 419 Chestnut Street
Wilmington, North Carolina 28401
Phone: [phone] • FAX: [phone]
June 23, 2008
NCDENR
Division of Water Quality
127 Cardinal Drive
Wilmington, NC 28405-3845
Attn: Mr. Steve Pusey
Re: Covil Gardens
New Hanover County, NC
SW8 080317
TE 07041
Dear Steve:
JUN z 8 4008
In response to your email comments dated June 12, 2008 we offer the following:
1. Impervious numbers have been updated.
2. Dimensions have been added and radii have been provided.
3. Dimensions for the buildings are the floor plan dimensions.
Please review for approval and contact us with any questions, comments or if
you need additional information. Thank you.
Sincerely,
Tripp Engineering, P.C.
Charles D. Cazier, P.
CDC:dcb
Enc.

Covil Gardens
Subject: Covil Gardens
From: Steve Pusey <[e-mail]>
Date: Thu, 12 Jun 2008 15:40:37 -0400
To: Charles Cazier <[e-mail]>
Charles,
In the final review, I noticed that the impervious areas on your plans don't match
the impervious areas listed in the application form. Please clarify. Furthermore,
we would like to see dimensions, radii, and slopes for roads, parking areas, and
sidewalks. Also, please include dimensions for the buildings and clarify whether
you are showing the roof plan or floor plan. Please revise and resubmit by no
later than June 26, 2008.
If you have any questions, please don't hesitate to call.
Regards,
Steve
Steve Pusey
Environmental Engineer
NCDENR - Division of Water Quality
Wilmington Regional Office
910-796-7334
1 of 1 6/17/2008 6:54 PM

07041
Cord Gardens
Pond r
Stormwater Calculations
Totat Drain a Area
ft.
I acres
84,076
1.93
Impervious Area
Land Use
sq.ft.
acres
Building
17,648
0.41
Asphalt Parking
28,075
0.64
Concrete
5,205
0.12
0
0.00
Total
50,928
1.17
Time of Concentration
Hydraulic Length (L) = 17 ft.
change in Height (H) = 10 ft.
TO = (L' /H) ° / 128
= 5.48 min.
Flow for 10 year, 6 hour Storm (Q1e)
QPRE _ (CPRE) x (110) x (Area)
3.04 cfs
QPOST = (CP T) x (110 x (Area)
8.27 cfs
Detention Pond Desicn:
Pond Size
Elevation
ft.
Surface Area
. ft.
Normal Pool
29.00
3,992
Flood Pool
31.00
5,524
Top of Bank
33.50
5,524
Bottom of Pool
20.00
74
Bottom of Shelf
28.50
1,093
Top of Shelf
29.50
4,141
% impervious = 0.606
= 60.6%
say 61.0%
CPRE - 0.25
CPOST= (%imp.)(.95)+(1-%imp.)(.25)
= 0.68
Iro = 6.30 in/hr
Imo= 7.79 Whr
Flax for 50 year, 6 hour Storm (Q,)
QPRE _ (CPRE] x (I10) x (Area)
3.76 cis
QPOST = (CP T) x (110) x (Area)
10.22 cis
State Surrace Area Hequirement at normal POOL
Pond side slopes = 3 1
Depth below N.P. = 4.9 ft.
SA/DA = 0.0437
(Chart for 90% TSS Removal for Wet Detention
Pond without Vegetative Fitter
Required SA = (SA/DA) x (Total Drainage Area)
3,674 sq. ft.
Total Provided Storage Volume: State Volume Reg. for Storage of first 1 S' runoff:
Vol. _ [(Normal pool SA + Flood Pool SA) / 2] Rv = .05+ ,009(% imp)
x (F.P elev. - N.P elev.) = 0.5951639
= 9,516 cu. ft. V= (Design minfall)(Rv)(Dminage Area)
= 6,255 cu, ft.
1C ARol����
\20. •�FESS/p i�
a� SEAL r•� -
032555 -
07041 pondl\l op 1 of 2

6/6/2008 Covil Gardens 07041
CDC Pond
Stonmrater Calculations
Pond Volume,
Bottom SA = 74 sq. ft.
Normal Pool SA = 3,992 sq. ft.
Vol. _ [(N.P. SA + Bottom SA) / 21 x (N.P. el. - Bottom el.)
18,297 cu. ft.
Forebav
Required Volume
Vol. = 20% of storage volume
3,659 cu. ft.
Provided Volume
Bottom SA =
222 sq. ft.
Normal Pool SA =
1,491 sq. ft.
Vol. _
[(N.P. SA + Bottom SA) / 21 x (N.P. el. - Bottom el.)
=
3,426 cu. ft.
depth =
4 ft.
Outlet Structure Desicn:
Flow for 2-day dmwdown:
for 1 st 15' of stonnwater,
Q = Required Vol. 1172,800 sec. (2-days)
0.036 cfs
Required Area of Pipe for 2-day drawdovm:
A= Q/ [Cd x SQRT(2 x g x h)]
Cd = 0.6
g = 322 ft./s2
h = (F.P. elev.- N.P. elev.) J2
A = 0.0075 sq. ft.
Diameter of Pipe for 2-day drawdo ,
DIA. = SORT[(A x 4) / pi]
0.0978 ft.
1 17 in.
Drawdown Calculation
21 snicOnfce Used=
Drawdown rate= 0.02
Drawdown time= 2.7621 d
Outlet Structure Check:
Using a 4' x N Basin,
Perimeter L = i6 ft.
Q = CIA
C = (% imp.)(.95) + (1-% imp.)( 25)
068
1 = 6.30 in. for a 10 yr. Stone
A = 1.93 Acres
= 8.27 cfs
Flow for 5-day dravvd n
for 1 st 1.5' of stormvmter,
Q = Required Vol. 1432,000 sec. (5-days)
0,014 cfs
Required Area of Pipe for 5-day drawdown:
A= Q/ [Cd x SQRT(2 x g x h)]
Cd = 0.6
g = 32.2 ftJsz
h = (F.P. elev. - N.P. elev.)/2
A = 0.0030 sq. ft.
Diameter of Pipe for 5-day drawdown.
DIA. = SQRT[(A x 4) / pi]
0.0619 ft.
0.74 in.
Q= CwxLx H'
H= [Q/(CwxQ]"
Cw = 3
= 0 31 ft.
Peak elevation = Flood pool elevation + H
31 31 ft.
07041 pondNewop 2 of 2

6=2008 Covnl Garderrs 07041
CDC SW mxrater Pond Rot&V.
1-year 24hr Storm
WATERSHED DATA
WATERSHED AREA
1.93 ACRES
HYDRAULIC LENGTH
627 FT
CHANGE IN HEIGHT
10 FT
RUNOFF COEF 'C'
025
TIME OF CONCENTR
5.48 MIN
INTENSITY 1 YR
5.63 IN/HR
Qa = 2.72 CFS
Qa = PRE -DEVELOPED PEAK DISCHARGE
COMPUTE DEPTH OF RUNOFF
P = 3 93 INCHES 1yr, 24hr PRECIPITATION
CN = 81
S = (1000/CN)-10
S = 2.35
Depth (D) _ (P-0 2S)A2/(P+0 8S)
D = 2.06 IN - 1yr, 24hr RUNOFF DEPTH
SET VOLUME AND COMPUTE TIME TO PEAK
Tp = ((43.5)(D)(Area)] / Qp
Tp= 23.44 MINUTES
Storage Volume Req'd = (Qp-Qa)'Tp'1 39*60
9,133 cu ft.
CALCULATE Ks AND b
SET NORMAL ELEVATION AT = 29.00 feet
WATERSHEDAREA
1.93 ACRES
HYDRAULIC LENGTH
627 FT
CHANGE IN HEIGHT
10 FT
RUNOFF COEF.'C'
0.68
TIME OF CONCENTR
5.48 MIN
INTENSITY 1 YR
5.63 IN/HR
Qp= 7.39 CFS
Qp = POST -DEVELOPED PEAK DISCHARGE
S
Z
CONTOUR
INCR
ACCUM
CONTOUR
AREA
VOL
VOL
STAGE
In S
In Z
Z est
(sq ft)
(cu ft)
(Cu ft)
(ft)
(ft)
290
3,992
0
0
0
0
0
0
300
4,758
4,375
4,375
1.0
8.3837
0
1.00
31.0
5.524
5,141
9,516
2.0
9.1607
0.6931
2.00
32.0
5,524
5,524
15,040
3.0
96185
1.0986
302
330
5,524
5,524
20,564
4.0
9.9313
1.3863
4.01
34.0
5,524
5,524
26,088
5.0
10.1692
1.6094
4.96
35.0
2,762
28,850
6.0
10.2699
17918
5.43
360
-
28,850
7.0
10.2699
1.9459
5.43
37.0
-
28,850
&0
10.2699
2.0794
5.43
Regression Output:
Ks =
4393
b =
1.11
Constant
839

6/6/2008 Covil Gardens 07041
CDC Stommater Pond Routing.
1-year 24hr Stone
CHAINSAW METHOD FOR
RISER BARREL ROUTING
STORM DATA
Oa =
2.72 cfs
Op =
7.39 cfs
Tp =
23.4 min
dT =
4 min
BASIN DATA
Ks =
4393
b=
1.11
Zo =
29.00 ft
Normal water elev =
29.00 It
Peak Outflow =
0.86 cfs
Box Weir Length =
16 ft
Peak Stage =
3158 ft
Cw =
3.0
Maximum Storage =
12,583 cu ft
Zcr =
32.50 ft
Control Holes
State Orifice:
Dia =
1.00 In
Dd =
18 in
Inv =
29.0 ft
Cd =
0.59
Weir
L =
7.5 in
Zi =
290 ft
Inv =
31.00 ft
Time
Inflow
Storage
Stage
Outflow
W Riser
Barrel
Orifice
City Weir
(min)
(cfs)
(cu ft)
(ft)
(cfs)
(cfs)
(cfs)
(cfs)
(cfs)
0
0.0
0
29.00
0
0
0
0
000
4
05
0
29.00
0
0.00
0
0
000
8
1.9
124
29.04
0.00
0.00
0.0
0.00
000
12
3.8
587
29.16
0.01
0.00
0.3
0.01
0 00
16
5.7
1505
29.38
0.02
0.00
0.9
0.02
000
20
7.0
2869
29.68
0.02
0.00
2.2
0.02
000
24
7.4
4545
30.03
0.03
0.00
4.1
003
0.00
28
6.7
6309
30.38
0.03
0.00
6.4
0.03
0.00
32
5.4
7915
30.70
0.03
0.00
8.1
.0.03
0.00
36
4.4
9212
30.95
0.04
0.00
9.1
0.04
0.00
40
3.5
10248
31.14
0.14
0.00
9.9
0.04
0.10
44
2.8
11052
31.29
0.33
0.00
10.4
0.04
0.30
48
2.2
11642
31.40
0.52
0.00
10.7
0.04
0.48
52
1.8
12055
31.48
0.66
0.00
11.0
0.04
0.62
56
1.4
12327
31.53
0.76
0.00
11.1
0.04
072
60
12
12489
31.56
0.82
0.00
11.2
0.04
078
64
0.9
12567
31.57
0.85
0 00
11.3
0.04
081
68
0.7
12583
31.58
0.86
0.00
11.3
0.04
082
72
0.6
12554
31.57
0.85
0.00
11.3
0.04
081
76
0.5
12492
31.56
0.82
0.00
11.2
0.04
078
80
0.4
12408
31.54
0.79
0.00
112
0.04
075
84
0.3
12308
31.53
0.75
0.00
11.1
0.04
0.71
88
0.2
12200
31.51
0.71
0.00
11.1
0.04
0.67
92
0.2
12087
31.48
0.67
0.00
110
0.04
063
96
0.2
11973
31.46
0.63
0.00
10.9
0.04
059
100
0.1
11859
31.44
0.59
0.00
109
0.04
055
104
0.1
11747
31.42
0.55
0.00
10.8
0.04
0.51
108
01
11638
31.40
0.52
0.00
10.7
0.04
0.48
112
0.1
11534
31.38
0.48
0.00
10.7
0.04
0.44
116
0.1
11433
31.36
0.45
0.00
10.6
0.04
0.41
120
00
11338
31.35
0.42
0.00
10.6
0.04
0.38
124
0.0
11247
31.33
0.39
0.00
105
0.04
0.35
128
0.0
11161
31.31
0.37
0.00
104
0.04
0.33
132
0.0
11079
31.30
0.34
0.00
10.4
0.04
0.30
136
0.0
11002
31.28
0.32
0.00
10.3
0.04
0.28
140
0.0
10929
31.27
030
0.00
10.3
0.04
0.26

6(6r2008
Covi1 Gardens
07041
CDC
Stomnrater Pond Routing.
1-year 24hr Storm
144
0.0
10860
31.26
0.28
0.00
10.3
0.04
0.24
148
0.0
10795
31.24
0.26
0.00
10.2
0.04
0.23
152
0.0
10734
31.23
0.25
0.00
10.2
0.04
0.21
156
0.0
10676
31.22
0.23
0.00
10.1
0.04
0.20
160
0.0
10621
3121
0.22
0.00
10.1
0.04
0.18
164
00
10569
3120
0.21
0.00
10.1
0.04
0.17
168
0.0
10520
31.19
0.20
0.00
10.0
0.04
0.16
172
0.0
10474
31.18
0.19
0.00
10.0
0.04
0.15
176
0.0
10429
31.18
0.18
0.00
10.0
0.04
0.14
ISO
0.0
10388
31.17
0.17
0.00
9.9
0.04
0.13
184
0.0
10348
31.16
0.16
0.00
9.9
0.04
0.12
188
0.0
10310
31.15
0.15
0.00
9.9
0.04
0.11
192
0.0
10275
31.15
0.14
0.00
9.9
0.04
0.11
196
0.0
10241
31.14
0.14
0.00
9.8
0.04
0.10
200
0.0
10208
31.13
0.13
0.00
9.8
0.04
009
204
0.0
10177
31.13
0.12
0.00
9.8
0.04
009
208
0.0
10148
31.12
0.12
0.00
9.8
0.04
0.08
212
0.0
10119
31.12
0.11
0.00
9.8
0.04
0.08
216
0.0
10092
31.11
0.11
0.00
9.8
0.04
007
220
0.0
10066
31.11
0.10
0.00
9.7
0.04
0.07
224
0.0
10042
31.10
0.10
0.00
9.7
0.04
0.06
228
0.0
10018
31.10
0.09
0.00
9.7
0.04
0.06
232
0.0
9995
31.09
0.09
0.00
9.7
0.04
0.05
236
0.0
9973
31.09
0.09
0.00
9.7
0.04
0.05
240
0.0
9952
31.09
0.08
0.00
9.7
0.04
0.05
244
00
9932
31.08
0.08
000
9.6
0.04
0.04
248
00
9913
31.08
0.08
0.00
9.6
0.04
0.04
252
0.0
9894
31 M
0.08
0.00
9.6
0.04
0.04
256
0.0
9876
31.07
0.07
0.00
9.6
0.04
0.04
260
OD
9859
31.07
0.07
0.00
9.6
004
003
264
0.0
9842
31.07
0.07
0.00
9.6
0.04
003
268
0.0
9825
31.06
0.07
0.00
9.6
0.04
0.03
272
00
9810
31.08
0.06
0.00
9.6
0.04
003
276
00
9794
31.06
0.06
0.00
9.5
0 04
0.03
280
00
9780
31.05
0.06
0.00
9.5
004
002
284
0.0
9765
31.05
0.06
0.00
95
0.04
002
288
0.0
9751
31.05
0.06
0.00
9.5
0.04
0.02
292
0.0
9738
31.05
0.05
0.00
9.5
0.04
0.02
296
0.0
9725
31.04
0.05
0.00
9.5
0.04
0.02
300
0.0
9712
31.04
0.05
0.00
9.5
0.04
0.02
304
0.0
9699
31.04
0.05
0.00
95
0.04
0.01
308
0.0
9687
31.04
0.05
0.00
95
0.04
0.01
312
00
9675
31.03
0.05
000
9.5
0.04
0.01
316
00
9664
31.03
0.05
0.00
9.5
0.04
0.01
320
0.0
9653
31.03
0.05
0.00
9.4
0.04
0.01
324
0.0
9642
31.03
0.04
0.00
9.4
0.04
0.01
328
0.0
9631
31.03
0.04
0.00
9.4
0.04
0.01
332
0.0
9620
31.02
0.04
0.00
9.4
0.04
0.01
336
0.0
9610
31.02
0.04
0.00
9.4
0.04
0.01
340
0.0
9600
31.02
004
0.00
9.4
0.04
0.01
344
0.0
9590
31.02
0.04
0.00
9.4
0.04
0.00
348
0.0
9580
31 02
0.04
000
9.4
0.04
0.00
352
00
9571
31.01
0.04
0.00
9.4
0.04
0.00
356
00
9561
31.01
0.04
0.00
9.4
0.04
0.00
360
0.0
9552
31.01
0.04
000
9.4
0.04
0.00
364
0.0
9543
31.01
0.04
0.00
94
0.04
0.00
368
0.0
9534
31.01
0.04
000
9.4
0.04
000
372
0.0
9525
31.01
0.04
000
9.4
0.04
0.00
376
0.0
9516
31.00
0.04
0.00
9.4
0.04
000
380
0.0
9507
31.00
0.04
0.00
93
004
0.00
384
0.0
9498
31.00
0.04
0.00
9.3
0.04
0.00
388
0.0
9490
31.00
0.04
0.00
93
0.04
0.00
392
0.0
9481
31.00
0.04
0.00
9.3
0.04
0.00
396
0.0
9472
31.00
0.04
0.00
9.3
0.04
0.00
400
0.0
9464
30.99
0.04
0.00
93
0.04
0.00
404
0.0
9455
30.99
0 04
0.00
9.3
0.04
0.00
408
0.0
9447
30.99
0.04
0.00
9.3
004
0.00

TRIPP ENGINEERING, P.C.
is 419 Chestnut Street
Wilmington, North Carolina 28401
Phone: [phone] • FAX: [phone]
May 6, 2008
NCDENR
Division of Water Quality
127 Cardinal Drive
Wilmington, NC 28405-3845
Attn: Mr. Steve Pusey
Re: Covil Gardens
New Hanover County, NC
SW8 080317
TE 07041
Dear Steve:
In response to your letter dated May 1, 2008 we offer the following:
RECEIVED
JUN " 6 7008
Y-------
I . Item 1 1 1.6 on page 2 has been corrected to 1.93 acres.
2. Average depth has been recalculated and the new SA/DA value is provided.
3. Surface areas and volumes have been updated.
4. We have been informed that a soils report is not necessary if the outlet
discharges to the wetlands. Our normal pool is above the wetlands we
discharge to therefore we should not cause the drainage of wetlands. An
approximate Seasonal High Water Table has been provided.
QA corrected O & M agreement is provided.
6. An updated supplement and revised drawdown calculations are provided.
J�7Q�. Revised calculations are enclosed.
V The pond detail has provided the correct clean out elevation and an
approximate Seasonal High Water Table Elevation.
/ The permanent pool contour has been dimensioned.
Please review for approval and contact us with any questions, comments or if
you need additional information. Thank you.
Sincerely,
Tripp Engineering, P.C.
CQ
Charles D. Cazier, P.E.
CDC:dcb
Enc.

F WATF
90
Mmhael P.
��
Easley, Governor
0 7
WdhamG Ross Jr, Secretary
> r
North Carolina Depanment of Environment and Natural Resources
-i
Coleen H. Sullins Director
Division of Water Quality
May 1, 2008
Randy Blanton, Owner
P.O. Box 10137
Wilmington, NC 28404
Subject: Request for Additional Information
Stormwater Project No. SW8 080317
Covil Gardens
New Hanover County
Dear Mr. Blanton:
The Wilmington Regional Office received a NPDES Phase II Post Construction Permit
Application for Covil Gardens on March 26, 2008. A preliminary review of that information has
determined that the application is not complete. The following information is needed to
continue the stormwater review:
1. Please change total project area to 1.93 acres on item 111.6 on page 2 of the
application.
2. Please recalculate the average pond depth using the correct depth from permanent
pool elevation to cleanout elevation, and enter the SA/DA tables with this average
pond depth. You may want to use the new average depth calculation formula to
maximize your average depth. Do not round numbers off until you get to the final
result.
3. Using the correct average depth, recalculate surface area and volume, and enter the
values in the supplement. Do not round numbers off until you get to the final result.
4. A soils report for all engineered systems is required. The report should contain the
estimated Seasonal High Water Table elevation at the wet pond location.
5. Please resubmit basin elevation diagram in the O&M Agreement with correct
sediment removal elevation, bottom elevation, and depth reading for sediment
removal.
Please recalculate the drawdown time based on the correct head and enter the new
values in the supplement. The average head to use in the orifice equation is
approximately one-third of the distance between the permanent pool elevation and
the elevation of the next available outlet above the permanent pool. Do not round
numbers off until you get to the final result.
7. Please provide a new table of elevations, areas, incremental volumes, and
accumulated volumes for overall pond and for forebay to verify volumes provided.
8. Pond section detail should include elevation for sediment cleanout and elevation of
seasonal high water table (SHWT).
9. Please provide dimensions for each line and arc formed b the permanent pool
contour. y p
N�o�`n Carolina
�Vatura(!y
North Carolina Division of Water Quality 127 Cardinal Drive Extension Wilmington, NC 28405 Phone [phone] Customer Service
Wilmington Regional Office Internet. www newaterqualtvorg Fax [phone]
An Equal OppoitunitylAffrmative Action Employer — 50 % Recycledl10% Post Consumer Paper

Randy Blanton
May 1, 2008
Stormwater Application No. SW8 080317
Please note that a revision to one number may have a domino effect on other numbers,
which may require revision of the applications, calculations, supplements, plans, details,
and associated documentation. Please verify all numbers are correct to ensure
consistency in the application documents.
Please note that this request for additional information is in response to a preliminary
review. The requested information should be received in this Office prior to May 30,
2008, or the application will be returned as incomplete. The return of a project will
necessitate resubmittal of all required items, including the application fee.
If you need additional time to submit the information, please mail, email or fax your
request for a time extension to the Division at the address and fax number at the bottom
of this letter. The request must indicate the date by which you expect to submit the
required information. The Division is allowed 90 days from the receipt of a completed
application to issue the permit.
The construction of any impervious surfaces, other than a construction entrance under
an approved Sedimentation Erosion Control Plan, is a violation of NCGS 143-215.1 and
is subject to enforcement action pursuant to NCGS 143-215.6A.
Please reference the State assigned project number on all correspondence. Any
original documents that need to be revised have been sent to the engineer or agent. All
original documents must be returned or new originals must be provided. Copies are not
acceptable. If you have any questions concerning this matter please feel free to call me
at [phone] or email me at [e-mail].
Sincerely,
"A� .� /
Steve G.Pusey
Environmental Engineer
ENB/sgp: S:\WQS\STORMWATER\ADDINFO\2008\080317.may08
CC: Charles Cazier, PE, Tripp Engineering, P.C.
Steve Pusey
Page 2 of 2

Re: Covd Gardens
Subject: Re: Covil Gardens
From: Steve Pusey <[e-mail]>
Date: Mon, 28 Apr 2008 17:08:04 -0400
To: [e-mail]
Yes, the old calculation will be okay in this case.
Steve
Charlie wrote:
Hey Ste ve,
I understand that the new calculation gives us a deeper a verage depth. Can we not
simply use the more conservative calculation for this submittal? I will be glad to use
your suggested method fro -in here on out.
Thank you,
Charles D. Cacier, P.E.
Tripp Engineering
910-763.5100
NOTICE: This electronic correspondence and all attachments may contain privileged information
intended only for the use of the addressee. Any information contained within this correspondence
is provided for your convenience. No assertion of accuracy is made by Tripp Engineering, P.C.
unless physical documents are obtained, sealed AND signed. User assumes all responsibility for
use of this digital information.
Steve Pusey
Environmental Engineer
NCDENR - Division of Water Quality
Wilmington Regional Office
910-796-7334
i
1 of 1 4/28/2008 5:24 PM

r;, . -1.
FAX COVER SHEET
Date:
4/24/08 No. of Pages: 2
To:
Charlie Cazier, PE From: Steve Pusey
Company:
Tripp Engineering Dept. of Surface Water Protection
FAX #:
910-763-5631 FAX # [phone]
Phone # [phone]
DWQ Stormwater Project Number: SW8 080317
Project Name: Covil Gardens
MESSAGE:
Please reference the attached new formula for calculating average pond depth.
This new formula takes into account that the permanent pool covers 5 feet of the
shallow shelf area (one half of the shelf area in the lateral direction). The result
is a greater average depth than that calculated by the old formula.
Please use this approved method to calculate the average depth for this project.
Thanks,
1-1
Steve77
ENB/sgp: S:\WQS\STORMWATERWDDINFO\2008\080317.apr08

1/egetalion notshown
*Freeboard & hardened
emergency overflow
not show,17
d.,,,: Average depth of permanent pool to use in the SA/DA tables (ft)
_ �.?5 X I -{- Ahm—shelf + Abot_shelf + Abot_prnt`( X De7ih / fi
boo shef
***Side slope stabilized per PIS judgment
Outlet above
temnorary nc
Temporary pool
Permanent pool
Bottom ol'vegetated shelf
Vegetated*
Side slope
Vegetated
shelf
I nli 1n.1
Forebav
Side slopes
—2 : I

RE: Covil Gardens
Subject: RE: Covil Gardens
From: "Charlie" <[e-mail]>
Date: Thu, 24 Apr 2008 14:31:29 -0400
To: "'Steve Pusey"' <[e-mail]>
Ste ve,
The average depth calculation is as follows
Sec 1`
(Np sf+ Btm sl)/2 Ap el — Btm el)/Np sf
The clean out elevation was done as the old 7516 rule. When the sediment reaches 75%
of the depth then that is when you clean it out. Iknow this is read differently now, so
Owe can change this if necessary. 14 `x 0.75 = 10.5' there fore 29e1— 10.5' = 18.5 el
/ That was the thought process. Please let us know if we need to revisit something.
Thank you for your pa tience,
Charles D. Caziei• P.E.
Tripp Engineering
910-763-5100
NOTICE: This electronic correspondence and all attachments may contain privileged information
intended only for the use of the addressee. Any information contained within this correspondence is
provided for your convenience. No assertion of accuracy is made by Tripp Engineering, P.C. unless
physical documents are obtained, sealed AND signed. User assumes all responsibility for use of this
digital information.
I of 1 4/24/2008 3:55 PM

TRwp ENGINEERING, P.C.
0 419 Chestnut Street
Wilmington, North Carolina 28401 ^� /
Phone: [phone] • FAX: [phone]
March 26, 2008 i
NCDENR
Division of Water Quality
127 Cardinal Drive
Wilmington, NC 28405-3845
Attn: Ms. Rhonda Hall
Re: Covil Gardens
New Hanover County, NC
TE 07041
Dear Rhonda:
NR -4
8 ?p0B
Enclosed please find two (2) sets of plans, one (1) stormwater permit application
form with narrative, one (1) wet detention basin supplement, two (2) sets of calculations,
wetland determination with map, and one check for the application fee.
Please review for approval and contact us with any questions, comments or if
you need additional information. Thank you.
Sincerely,
Tripp Engineering, P C.
aw
Charles D. Cazier, P.
CDC:dcb
Enc.

1 /22/2008
CDC
Cant Garden*
Pond 1 Calcuations
5 O 07041
Total Drainage Area
sq ft
acres
84.076
1 93
Ira emous Aran
Land Use
sq. R
aches
buildings
17,648
0.41
rkin /as halt
28,075
0.64
Concrete
5,205
0.12
Total
1 50,928
1.17
Stormwater Calculations'
Time of Concentration
Hydraulic Length (L) = 627 ft.
change in Height (H) = 10 ft.
Tc = (L'1H)—/128
548 min
Flow for 2 year, 6 hour Storm (CJ
CPRE _ (CPRE) x (I2) x (Area)
2.55 cfs
CPosT = (CPosT) x (I2) x (Area)
6.93 cfs
Soil Storage Capacity for 2 year Storm
CN = (98)(% imp) + (60)(1-
= 84
P = 3 30 in. (or2yr, 6 hr storm
S = 1000/CN - 10
190
Depth (Dp [P-(02)(S)]'!
1.77
Time to Peak Flow
TP= [(435)(D)(Area))/Dx
21 40 min
Detention Pond Design
Pond Size,
Elevation
(ft)
Surface Area
(sq. R)
Normal Pool
2900
2.220
Flood Pool
31 W
4,008
To of Bank
32.00
4,852
Bottom of Pool
15 00
5
Provided Storage Volume:
Vol_ _ [(Normal pool SA+ Flood Pool SA) 12]
x F.P. elev - N.P elev )
6,228 cu. ft.
RECEIVED
MAR 2 6 2008
BY:
07041pondl
%impemous= 0.61
= 606%
say 61 0%
CPRE = US
C,,,,= (%imp.)(95)+(1-%imp)(25)
068
1,= 528 in/hr
Zia= 6.30 m/hr
Flaw for 10 year, 6 hour Storm (Clio)
oPVE _ (CP'E) x (1+o) x (Area)
3 04 cfs
CPosT = (CPosT) x (Ira) x (Area)
= 8 27 cfs
CN= (98)(%imp) +(60)(1-%imp.)
= 84
P = 4.82 in for 10 yr, 6 hr storm
S= IOOO/CN-10
190
Depth (D)= [P-(0.2)(S)]` / [P+(0 8)(S)I
= 3.11 in
Time to Peak Flow'
TP= [(43.5)(D)(Area))/Oio,RosT
31 54 min.
State Surface Area Requirement at normal pool.
Pond side slopes = 3 1
Avg D below N.P. = 7.0 ft.
SA/DA = 0.0245
(Chart for 90% TSS Removal for Wet Detention
Pond without VeqeMtrve Filter)
Required SA = (SA/DA) x (Total Drainage Area)
2,060 sq. ft.
State Volume Reauued for Storage of first 1.5" of runoff
Rv = 05+ 009(% imp)
0 529
V= (Design ramfall)(Rv)(Drainage Area)
5.560 cu. ft.
-0\ C IA R �1%
o -
`2: a SEAT. 9f .
_ 0325a5 _
in . VGIP\ti.4���t��
ES 0. G
i of 2 1- 22— ZPV5

1/222008 Covil Gardens 07041
CDC Pond 1 Calculations
Pond Volume:
Main Pool Bottom SA = 5 sq. R
Main Normal Pool SA = 1,323 sq. ft-
Vol = ([(M P.N.P. SA + Bottom SA)121 x (M.P.N.P. el. - Bottom el.)H(F.B.N P SA + Bottom SA) / 21 x (F.B.N.P. el. - Bottom el.)
11,523 cu. ft
orF
Required Volume
Vol. = 20% of storage volume
2,305 cu. R
Outlet Structure Design.
Flow for 2-day dawdown.
for 1 st 1 5' of stormwater,
O = Required Vol. / /72,800 sec. (2-days)
0.032 cfs
Reouued Area of Pice for 2dav dawdown
A= Q/fCdxSQRT(2xgxh)]
Cd = 0.6
9 = 32.2 ftJs1
h = IF P elev.- N.P. elev.) 2
A = 00067 sq. ft.
Diameter of Pace for 2dav dawdown
DIA. = SQRT[(A x 4) / pi]
= 0.0922 ft_
= 1.11 in.
'Use1.00 in diameter pipe
Outlet Structure Check:
Using a 5 x 5 Basin,
Perimeter (L) = 24 ft
Q = CIA
C = I% imp.)(.95) + (1-% imp)(25)
068
1 = 6 30 in for a 25 yr. Storm
A= 1 93 Acres
827 cfs
Q= CwxLx H'
H= (Q/(CwxL)]'
Cw= 3
0.24 ft
Peak elevation - flood pool elevation + H
31 24 ft.
Provided Volume
Bottom SA = 92 sq. fL
Normal Pool SA = 897 sq. ft
Vol. _ [(F B.N P. SA + Bottom SA) / 21 x IF B.N P. el. - Bottom el.)
= 2,225 cu, ft.
Flow for ay dawdown'
for 1st 1.5' of stormwater,
O = Required Vol. / 432,000 sec. (5-days)
0.013 cfs
Required Area of Pipe for 5-day dawdown'
A= Q/[Cdx SORT(2xgxh)]
Cd= 06
9 = 32 2 ftJs'
It = (F.P elev - N.P. elev) / 2
= ft.
A= 00027 sq ft,
Diameter of Pice for 5-day drawdown'
DIA = SQRT[(A x 4) / pi]
0.0583 ft
0.70 in.
07041 pondl 2 of 2

122/2008
CDC
WATERSHED DATA
BEFORE DEVELOPMENT
WATERSHED AREA
1.93 ACRES
HYDRAULIC LENGTH
627 FT
CHANGE IN HEIGHT
10 FT
RUNOFF COEF.'C'
0.25
TIME OF CONCENTR
5.48 MIN
INTENSITY (1 YR)
5.63 IN/HR
Qa= 2.72 CFS
Qa = PRE -DEVELOPED PEAK DISCHARGE
COMPUTE DEPTH OF RUNOFF
Cavil Gardens
Storm ater Pond Routing
1-year 24hr Stonn
P = 3.93 INCHES 1yr, 24hr PRECIPITATION
CN = 81
S = (1000/CN)-10
S = 2.35
Depth (D) _ (P-0 2S)^2/(P+0.8S)
D= 2061N- lyr, 24hr RUNOFF DEPTH
SET VOLUME AND COMPUTE TIME TO PEAK
Tp = [(43 5)(D)(Area)] / Qp
TIP = 23.44 MINUTES
Storage Volume Req'd = (Op-Qa)'Tp'l 39'60
9,133 cu ft.
CALCULATE Ks AND b
SET NORMAL ELEVATION AT = 29.00 feet
WATERSHED AREA
1.93 ACRES
HYDRAULIC LENGTH
627 FT
CHANGE IN HEIGHT
10 FT
RUNOFF COEF.'C'
0.68
TIME OF CONCENTR
5.48 MIN
INTENSITY (1 YR)
5.63 IN/HR
Qp= 7.39 CFS
Op = POST -DEVELOPED PEAK DISCHARGE
S
Z
CONTOUR
INCR
ACCUM
CONTOUR
AREA
VOL
VOL
STAGE
In S
In Z
Z est
(sq ft)
ICU ft)
(cu ft)
(ft)
(ft)
290
2,220
0
0
0
0
0
0
300
3,114
2,667
2,667
1.0
T8887
0
1.01
310
4.008
3.561
6,228
2.0
8.7368
0.6931
1.97
32.0
4,852
4,430
10,658
3.0
9.2741
1.0986
300
330
4,852
4,852
15,510
4.0
9.6492
1.3863
4.03
340
4,852
4,852
20.362
5.0
9.9214
1.6094
5.00
350
2.426
22.788
60
10.0340
1.7918
546
36.0
-
22,788
70
10.0340
1.9459
546
370
-
22,788
80
10.0340
2.0794
546
Regression Output:
__> Ks =
2639
b =
1.27
Constant
788
'0491E

1 /2212008 Covil Gardens
CDC Storrrnrater Pond Routing
1-year 24hr Storm
CHAINSAW METHOD FOR
RISER BARREL ROUTING
STORM DATA
Qa =
2.72 cfs
Qp =
7.39 cis
Tp =
234 min
dT =
4 min
BASIN DATA
Ks =
2639
b =
1 27
Zo =
2900 It
Normal water elev =
29.00 It
Peak Outflow =
196 cfs
Box Weir Length =
16 It
Peak Stage =
3201 It
CW =
3.0
Maximum Storage =
10.712 cu It
Zcr =
32.50 It
Control Holes:
State Onfice.
Dia =
1 00 in
Dd =
24 in
Inv =
290 ft
Cd =
0.59
Weir:
L =
75 in
Zi =
29.0 it
Inv =
31 00 it
Time
Inflow
Storage
Stage
Outflow
W Riser
Barrel
Orifice
City Weir
(min)
(cfs)
(cu ft)
(ft)
(CIS)
(CIS)
(CIS)
(CIS)
(CIS)
0
00
0
29.00
0
0
0
0
000
4
0.5
0
29.00
0
0.00
0
0
000
8
1.9
124
29.09
0.01
0.00
0.1
001
0.00
12
3.8
586
2931
0.01
000
0.9
001
000
16
57
1503
2964
0.02
0-00
2.7
0.02
000
20
70
2866
3007
0.03
000
5Z
0.03
0.00
24
74
4540
3053
0.03
000
100
0.03
000
28
67
6304
30.99
0.04
0.00
147
0.04
0.00
32
5.4
70-M
31.37
0.47
0.00
174
0.04
0.43
36
4.4
9100
31.65
1 03
000
191
004
098
40
3.5
9899
31.83
1.47
0.00
20.1
0.04
142
44
2.8
10384
31.94
1 76
0.00
207
0.04
1.71
48
2.2
10633
32.00
191
0.00
21.0
0.04
186
52
1 8
10712
3201
1 96
0.00
21.1
0.04
1.91
56
14
10672
3Z01
193
0.00
2L0
0.04
1.89
60
1.2
10553
31 98
1 86
0.00
20.9 _
004
1 82
64
0.9
10383
31.94
1 75
0.00
20.7
004
1 71
68
0.7
10183
31.90
1 63
0.00
20.4
004
1 59
72
0.5
9968
31.85
1.51
0.00
20.2
0.04
1.46
76
0.5
9748
31.80
1.38
0.00
199
004
1 34
80
04
9530
31 75
1 26
000
196
0.04
1.22
34
03
9320
31.70
1 14
000
194
004
1 10
88
0.2
9118
31.65
1.04
0.00
191
004
099
92
02
8928
31 61
0.94
0.00
189
004
090
96
02
8750
31.57
0.85
000
186
004
081
100
0 1
8584
31 53
0 77
0 00
18.4
004
073
104
01
8430
31 50
0.69
000
182
004
0.65
108
0.1
8287
31.46
063
000
180
004
059
112
0.1
8155
31 43
057
0 00
178
004
053
118
0.1
8034
31 40
052
&GO
1 Z6
0.04
048
120
0.0
7921
3138
0.47
0 DO
174
004
043
124
0.0
7818
31.35
043
0.00
173
0.04
039
128
00
7723
3133
0.39
0-00
17.1
0.04
0.35
132
00
7635
31 31
0.36
0.00
17.0
0.04
032
136
0.0
7553
31 29
0.33
0.00
16.9
0.04
029
140
00
7478
31 27
0.30
0.00
16.7
0.04
026
07D41

1/22/2008
C IGrddens
07041
CDC
Stoarmater Pond Routing
1-year 24hr Storm
144
0.0
7409
31.25
028
0.00
16.6
0.04
0.24
148
0.0
7344
31.24
026
0.00
16.5
0.04
0.22
152
0.0
7285
3122
0.24
0.00
16.4
0.04
020
156
00
7229
3121
0.22
0.00
16.3
0.04
018
160
0.0
7178
31.20
0.20
0.00
16.3
0.04
0.17
164
00
7130
31.19
0.19
0.00
16.2
0.04
0.15
168
00
7085
31.18
0.18
0.00
16.1
0.04
0.14
172
0.0
7044
3117
0.16
0.00
16.0
0.04
0.13
176
00
7005
31.16
0.15
0.00
16.0
004
0.12
180
0.0
6968
31.15
0.14
0.00
15.9
0.04
011
184
0.0
6934
31.14
0.14
0.00
159
004
010
188
00
6902
31.13
0.13
000
158
0.04
009
192
0.0
6871
31.12
0.12
0.00
15.7
004
008
196
00
6843
31.12
Oil
0.00
15.7
004
008
200
00
6816
31.11
Oil
0.00
157
0.04
007
204
00
6790
31.10
0.10
000
15.6
0.04
006
208
0.0
6766
31.10
010
000
156
0.04
006
212
00
6743
31 09
0.09
000
15.5
0.04
0.05
216
0.0
6722
31 09
0.09
0.00
15.5
004
0.05
220
0.0
6701
31 08
0.08
000
15.5
004
0.04
224
0.0
6682
31.08
0.08
0.00
154
0.04
004
228
0.0
6663
31.07
0.07
0.00
15.4
0.04
004
232
0.0
6645
31.07
0.07
0.00
15.4
0.04
003
236
0.0
6628
31 07
007
0.00
15.3
0.04
003
240
00
6612
31.06
a07
0.00
15.3
0.04
0.03
244
00
6596
31.06
006
000
15.3
0.04
003
248
0.0
6581
31 05
006
0.00
152
0.04
0.02
252
0.0
6567
31.05
006
0.00
152
004
0.02
256
0.0
6553
31.05
006
0.00
152
0.04
002
260
0.0
6540
31.04
0.05
0.00
152
0.04
002
264
0.0
6527
31.04
0.05
0.00
151
0 04
002
268
0.0
6515
31.04
0.05
0 00
15.1
0.04
0.01
272
00
6503
31.03
005
000
151
0.04
001
276
00
6491
31.03
0.05
000
15.1
0.04
001
280
0.0
6480
31.03
0.05
000
15.1
0.04
001
284
00
6469
31.03
0.04
000
15.0
0.04
001
288
0.0
6455
31 02
0.04
000
150
004
001
292
0.0
6448
31 02
0 Oa
000
15.0
004
0.01
296
00
6438
31 02
004
0.00
15.0
0.04
0.00
300
00
6428
31 02
004
0-00
15.0
0.04
000
304
0.0
6419
31 01
004
0.00
150
0.04
000
308
00
6409
31 01
004
0 00
14.9
0.04
000
312
00
6400
31 01
004
0.00
149
0.04
0.00
316
0.0
6391
31 01
004
OM
149
0.04
000
320
0.0
6382
31 00
004
0.00
149
0.04
0.00
324
0.0
6373
31 00
0.04
0.00
149
0.04
0.00
328
0.0
6364
31 00
0.04
000
149
0 04
0.00
332
0.0
6356
3100
0.04
0.00
14.9
0.04
0.00
336
0.0
6347
31 00
0.04
0.00
14.9
004
000
340
00
6338
3099
004
000
14.8
004
0.00
344
00
6330
3099
004
000
148
004
0.00
348
00
6321
3099
004
000
148
004
0.00
352
00
6313
3099
004
000
148
0.04
000
356
0.0
6304
3099
004
0 00
147
004
000
360
0.0
6295
30.98
004
000
147
004
000
364
0.0
6287
30.98
004
000
14.7
004
000
368
00
6278
30.98
004
000
147
004
000
372
00
6269
30.98
0 04
000
14.6
004
000
376
00
6261
30.97
004
000
14.6
0.04
0.00
380
00
6252
3097
004
0.00
14.6
0.04
0.00
384
00
6244
90.97
004
000
14.6
004
000
388
0.0
6235
30.97
0.04
000
14.5
004
0.00
392
0.0
6226
3097
004
0.00
14.5
0.04
0.00
396
0.0
6218
3096
0.04
0.00
14.5
0.04
000
400
0.0
6209
30.96
0.04
OM
14.5
0.04
000
404
0.0
6201
3096
0.04
0.00
14.4
0.04
000
408
0.0
6192
3096
004
0.00
14.4
0.04
000

RECEIVED
MAR ? 6 2008
Action i$SA' W-2008-00519
WILMINGTON DISTRICT
U.S.G.S. Quad: Wilmington
"<wf dYa3 1 7
U nt 5-G>-W6 tLL&;
County: New Hanover
NOTIFICATION OF JURISDICTIONAL DETEMM INATION
Property Owner: Randv Blanton
Address: PO Box 10137
Wilmington. NC 28404
Telephone No: 910-270-1138
Property description:
Size (acres) 2.22
Nearest Waterway Burnt Mill Creek
USGS HUC 03030007
Agent: Southern Environmental Group. Inc
attn: David Scibetta
5315 College Road, Suite E
Wilmington, NC 28412
910452-2711
Nearest Town Wilmington
River Basin Northeast Cape Fear River
Coordinates N 34.2365 W-77.9038
Location description The property is located at 115 Covil Avenue (parcel ID# R04917-004-010-000), New Hanover
Countv, Wilmington, North Carolina.
Indicate Which of the Following Apply:
A. Preliminary Determination
_ Based on preliminary information, there may be wetlands on the above described property. We strongly suggest you have
this property inspected to determine the extent of Department of the Army (DA) jurisdiction. To be considered final, a
jurisdictional determination must be verified by the Corps. This preliminary determination is not an appealable action
under the Regulatory Program Administrative Appeal Process ( Reference 33 CFR Part 331).
B. Approved Determination
There are Navigable Waters of the United States within the above described property subject to the permit requirements of
Section 10 of the Rivers and Harbors Act and Section 404 of the Clean Water Act. Unless there is a change in the law or
our published regulations, this determination may be relied upon for a period not to exceed five years from the date of this
notification.
X There are wetlands on the above described property subject to the permit requirements of Section 404 of the Clean
Water Act (CWA)(33 USC S 1344). Unless there is a change in the law or our published regulations, this
determination may he relied upon for a period not to exceed five vears from the date of this notification.
We strongly suggest you have the wetlands on your property delineated. Due to the size of your property and/or our
present workload, the Corps may not be able to accomplish this wetland delineation in a timely manner. For a more timely
delineation, you may wish to obtain a consultant. To be considered final, any delineation must be verified by the Corps.
The wetland on your property have been delineated and the delineation has been verified by the Corps. We strongly
suggest you have this delineation surveyed. Upon completion, this survey should be reviewed and verified by the Corps.
Once verified, this survey will provide an accurate depiction of all areas subject to CWA jurisdiction on your property
which, provided there is no change in the law or our published regulations, may be relied upon for a period not to exceed
five years.
X The wetlands have been delineated and surveved and are accurately depicted on the plat signed by the Corps
Regulatory Official identified below on 03/21/2008. Unless there is a change in the law or our published
regulations, this determination may be relied upon for a period not to exceed five years from the date of this
notification.
There are no waters of the U.S., to include wetlands, present on the above described project area which are subject to the
permit requirements of Section 404 of the Clean Water Act (33 USC 1344). Unless there is a change in the law or our
Page 1 of

puousnea regutauons, mis determination may be relied upon for a period not to exceed rive years from the date of this
notification.
X_ The property is located in one of the 20 Coastal Counties subject to regulation under the Coastal Area Management
Act (CAMA). You should contact the Division of Coastal Management in Wilmington at 910-796-7215 to
determine their requirements.
Placement of dredged or fill material within waters of the US and/or wetlands without a Department of the Army permit may
constitute a violation of Section 301 of the Clean Water Act (33 USC § 1311). If you have any questions regarding this
determination and/or the Corps regulatory program, please contact Jessica Hooted at 910-2514637 or Min Garvev at
910-2514482.
C. Basis For Determination
This site exhibits wetland criteria as described in the 1987 Corps Wetland Delineation Manual and are adiacent to
Burnt Mill Creek. which Bows into Smith Creek, a Traditional Navigable Water of the U.S-
D. Remarks
This determination is based on information provided by Southern Environmental Group. Inc and by site visit
conducted by Jessica Hooten on 02/11/2008.
E. Appeals Information (This information applies only to approved jurisdictional determinations as indicated in
B. above)
This correspondence constitutes an approved jurisdictional determination for the above described site. If you object to this
determination, you may request an administrative appeal under Corps regulations at 33 CFR part 331. Enclosed you will find a
Notification of Appeal Process (NAP) fact sheet and request for appeal (RFA) form. If you request to appeal this
determination you must submit a completed RFA form to the following address:
District Engineer, Wilmington Regulatory Division
Attn: Jessica Hooten, Project Manager,
Wilmington Regulatory Field Office
PO Box 1890
Wilmington , North Carolina 28402
In order for an RFA to be accepted by the Corps, the Corps must determine that it is complete, that it meets the criteria for
appeal under 33 CFR part 331.5, and that it has been received by the District Office within 60 days of the date of the NAP.
Should you decide to submit an RFA form, it must be received at the above address by 05/21/2008.
**It is not necessary to submit an RFA form to die District Office if you do not objec die determination in this
correspondence."
Corps Regulatory Official: •�7/'�.t,ly CtOa(fi•y ��
Date 03/21/2008
Expiration Date 03/21/2013
The Wilmington District is committed to providing the highest level of support to the public. To help us ensure we continue to
do so, please complete the Customer Satisfaction Survey located at our website at http://reeulaturv.usacesurvev.com/ to
complete the survey online.
Page 2 of 2

16
N
89'36'49"
W
27.97
L7
N
69-29'33"
W
22.47
L8
S
29'45'48"
W
45.04
L9
S
37'15'18"
W
24.43
LID
S
28'32'36"
E
26.99
111
S
74'41'03"
E
22.37
L12
S
82'58'08"
E
19.47
L13
N
70'11'32"
E
19.32
L14
N
44'34'45"
E
26.93
L15
N
51'44'33"
E
24.43
L16
N
21'16'04"
E
13.53
L17
N
43'38'53"
E
42.21
L18
S
04'02'13"
W
26.66
1-79
S
03'03'58"
W
37.41
S 03'03'58" W
69.98'
Tie Line 1
01'29'26" E -
149.97'
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Manual, as determined by the
undersigned on this date. Unless L
there Is a change In the low of
our published regulations, this
determination of Section 404
Jurisdiction may be relied upon for
a period of five years from this
o S7 Army Corp �JKrL
of Engineers Official
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DB 4942 Pg 1251
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I DB 5017 Pg 919
n/f
Peter R. &
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w
Catherine R. Davis
DB 4359 Pg 660
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See Inset"B" Covil
E 290.87
Avenue
AI 1 I I--
Rc'� I I BROAD Sr
VIICINITY MAP N.T.s.
Notes:
1) 404 Wetland area Is
7,940 s.f. Q.' 1� C,(r.I S
2) Wetlands flagged by.
Southern Environmental
Group, Inc.
5315 South College Rd
Wilmington, NC 28403
pw
`-'- IFEB 2 5 2008
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141.22'
(60' Public
R/W)
— — — — — — — — — — — — — — — — — — — —
Scale: 1 "=100' Legend,
0 Existing Iron Pipe
100' 50' 0' 100" I] Existing Monument
WETLAND SURVEY FOR:
Randy Blanton
115 Covil Avenue
2.22 Acres
City of Wilmington, New Hanover County, NC
Date: September 28, 2007
Survey Reference:
I, Paul D. Talbot, do certify that
this actual survey and map was
�.`'Z\{ CAROB,,
performed and drawn under my ;��0�:'ESSi."••. y
supervision in accordance with
"The
Standards of Practice for _
SEAL
Land Surveying in North Carolina" _
JCYS
`
witness my original signature,
L-4099
license ,nufnber ands I.pNp.SURlE,t``�:
Paul . TaTbot.P.L.S. L-4099
0

January 25, 2008
Stormwater Narrative
Covil Gardens
Wilmington, NC
TE 07041
Covil Gardens is a vacant 2.22-acre tract proposed for a multifamily project. Proposed
impervious areas include 17,648 sf of building, 28,075 sf of parking area, and 5,205 sf of
concrete sidewalk. This a total built upon area of 50,928 sf or 52.66% total impervious
area. All impervious area will be routed to the proposed wet detention pond.
The pond is sized for 1.93 acres and 50,928 sf (1.17 ac) total impervious area. The pond
will treat runoff for the State's 1.5", 1-year 24-hour pre -post and the City's 10-year pre -
post requirements. Overflow from this basin will be directed to Burnt Mill Creek,
classification C-SW.