SW8040124_HISTORICAL FILE_20040827

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW
DOC TYPE
❑ CURRENT PERMIT .
❑ APPROVED PLANS
HISTORICAL FILE
❑ COMPLIANCE EVALUATION INSPECTION
DOC DATE
�Og�
YYYYMMDD

State Stormwater Management Systems
Permit No. SWS O40124
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
Allan Rappuhn, Canebreak, L.P.
Canebreak Apartments
Lullwater Drive, 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 August 27, 2004, and shall
be subject to the following specified conditions and limitations:
I. DESIGN STANDARDS
This permit is effective only with respect to the nature and volume of stormwater
described in the application and other supporting data.
2. This stormwater system has been approved for the management of stormwater
runoff as described in Section 1.6 on page 3 of this permit. The stormwater
control has been designed to handle the runoff from 93,046 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.
'1
5. The runoff from all built -upon area within the permitted drainage area of this
project must'be directed into the permitted stormwater control system.
Page 2 of 7

State Stormwater Management Systems
Permit No. SW8 040124
6. 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, ft2:
C. Design Storm, inches:
d. Pond Depth, feet:
e. TSS removal efficiency:
f. -Permanent Pool Elevation, FMSL:
g. Permanent Pool Surface Area, ft2:
h. Permitted Storage Volume, ft3:
i. Temporary Storage Elevation, FMSL
j. Controlling Orifice:
k. Permitted Forebay Volume, ft3:
I. Receiving Stream/River Basin:
m. Stream Index Number:
n. Classification of Water Body:
II. SCHEDULE OF COMPLIANCE
3.81
165,964
0
93,046
,10
5.0
90%
35.40
11,067
13,387
36.53
1"O pipe
10,454
Burnt Mill Creek 1 Cape Fear
CPF17 18-74-63-2
"C Sw"
1. The stormwater management system shall be constructed in its entirety,
vegetated and operational for its intended use prior to the construction of any
built -upon surface.
2. During construction, erosion shall be kept to a minimum and any eroded areas of
the system will be repaired immediately.
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.
;r
Page 3 of 7

State Stormwater Management Systems
Permit No. SW8 040124
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 be allowed in the stormwater treatment system,
subject to the following criteria:
a. The fountain must draw its water from less than 2' below the permanent
pool surface.
b. Separated units, where the nozzle, pump and intake are connected by
tubing, may be used only if they draw water from the surface in the
deepest part of the pond.
c. The falling water from the fountain must be centered in the pond, away
.from the shoreline.
d. The maximum horsepower for a fountain in this pond is 118 HP
horsepower.
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 priorto occupancy of the facility.
9. Access to the stormwater facilities shall be maintained via appropriate
easements at all times.
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. Fdrther 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 permittee shall submit final site layout and grading plans for any permitted
future areas shown on the approved plans, prior to construction.
12. 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 4of7

State Stormwater Management Systems
Permit No. SW8 040124
13. The Director may notify the permittee when the permitted site does not meet one
or more of the minimum requirements of the permit. Within the time frame
specified`'in the notice, the permittee shall submit a written time schedule to the
Director for modifying the site to meet minimum requirements. The permittee
shall provide copies of revised plans and certification in writing to the Director
that the changes have been made.
III. GENERAL CONDITIONS
This permit is not transferable except after notice to and approval by the Director.
In the event of a change of ownership, or a name change, the permittee must
submit a formal permit transfer request to the Division of Water Quality,
accompanied by a completed name/ownership change form, documentation
from the parties involved, and other supporting materials as may be appropriate.
The approval of this request will be considered on its merits and may or may not
be approved. The permittee is responsible for compliance with all permit
conditions until such time as the Division 'approves the transfer request.
2. Failure to abide by the conditions and limitations contained in this permit may
subject the Permittee to enforcement action by the Division of Water Quality, in
accordance with North Carolina General Statute 143-215.6A to 143-215.6C.
3. The issuance of this permit does not preclude the Permittee from complying with
any and all statutes, rules, regulations, or ordinances, which may be imposed by
other government agencies (local, state, and federal) having jurisdiction.
4. In the event that the facilities fail to perform satisfactorily, including the creation
of nuisance conditions, the Permittee shall take immediate corrective action,
including those as may be required by this Division, such as the construction of
additional or replacement stormwater management systems.
5. The permittee grants DENR Staff permission to enter the property during normal
business.;hours for the purpose of inspecting all components of the permitted
stormwater management facility.
6. The permit may be modified, revoked and reissued or terminated for cause. The
filing of a request for a permit modification, revocation and reissuance or
termination does not stay any permit condition.
7. Unless specified elsewhere, permanent seeding requirements for the stormwater
control must follow the guidelines established in the North Carolina Erosion and
Sediment Control Planning and Design Manual.
8. Approved plans and specifications for this project are incorporated by reference
and are enforceable parts of the permit.
9. The permittee shall notify the Division any name, ownership or mailing address
changes within 30 days.
Permit issued this the 27th day of August, 2004.
NORTH CAROLINA ENVIRONMENTAL MANAGEMENT COMMISSION
Alan W. Klimek, P.E., Director
Division of Water Quality
By Authority of the Environmental Management Commission
Page 5 of 7

McKEAN & A
A R C H I T E C T S
August 5, 2004
NCDENR
Wilmington Regional Office
127 Cardinal Drive Extension
Wilmington, NC 28405
(Courier 04-16-33)
910/395-3900
FAX [phone]
Re: Stormwater Application No. SW8 040124
Linda Lewis:
TES
L L C
RECEIVED
AUG 0 6 2004
DWQ
Included are the revised calculations and plans for the State Sewer Permit for
Canebreak Apartments. I f you have any questions. call me at [phone].
Sincerely,
Brice Taylor
2815-B Zelda Road, Montgomery, Alabama 36106, Telephone [phone], Facsimilie [phone]

OF WATER Michael F. Easley, Governor
p William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Alan W. Klimek, P.E.,Director
p Division of Water Quality
Coleen H. Sullins, Deputy Director
Division of Water Quality
March 26, 2004
Mr. Allan Rappuhn, Managing Member
Canebreak, LP
PO Box 220
Florence, AL 35631
Subject: Request for Additional Information
Stormwater Project No. SW8 040124
Canebreak Apartments
New Hanover County
Dear Mr. Rappuhn:
The Wilmington Regional Office received a Stormwater Management Permit Application
for Canebreak Apartments on January 20, 2004. 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 either delineate all wetlands on site, disturbed or undisturbed, or note on
the plans that none exist.
2. Since Mr. Kenneth White is your consultant, and is providing information
regarding this application, please complete Section VI on page 4 of the
application.
3. Please delineate the single overall drainage area to the pond. It appears from the
post -runoff pond data tabulation that only 4.34 acres is draining to the pond,
while 5.25 acres has been reported on the supplement and is used in the pond
sizing calculations.
4. There appears to be runoff entering this project from the adjacent Manassas and
Tatum Family properties, as well as from the single family lots to the south.
Please either provide a means for this runoff to bypass the pond, or include these
numbers in the pond's drainage area and impervious area at 90% build -out.
5. The runoff from all of the proposed built -upon area, including the backs of all the
buildings and access drives, must either'be directed into the pond or a separate
engineered treatment system must be provided. It appears from the drainage
area sheet that areas 13 and 15, which contain built -upon area, will not be
directed into the pond.
6. Please provide a list of wetland species to be planted on the 6:1 shelf.
7. Please add a note to the plans that all roof drainage must be directed to the
forebay of the proposed pond.
N. C. Division of Water Quality 127 Cardinal Drive Extension [phone] Customer Service A*'A
Wilmington Regional Office Wilmington. NC 28405 [phone] Fax [phone] NCE)ENR

Mr. Rappuhn
March 26, 2004
Stormwater Application No. SW8 040124
8. Please add a typical building detail showing dimensions, and identifying all
covered decks or stairs, sidewalk, patios, etc.
9. Please specify a trash rack for the outlet structure. Maximum openings are 4
inches square.
10. The basin diagram on page 3 of the supplement indicates that the permanent
pool elevation is 42.26, while page one of the supplement and the plans report
that the permanent pool elevation is 35.40. Please correct and revise.
Additionally, the cleanout depths have been reported as elevations instead of
depths. Based on a 5.4' deep pond, the cleanout depth is 4.05'. Please make the
appropriate corrections and resubmit.
Please note that this request for additional information is in response to a preliminary
review. The requested information should be received by this Office prior to April 26,
2004, 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 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].
Sincerely,
Linda Lewis
Environmental Engineer
RSS/arl: S:IWQSISTORMWATIADDINF0120041040124.mar04
cc: Kenneth White, P.E.
Linda Lewis
Page 2 of 2

OF WArFR Michael F. Easley, Governor
William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
Alan W. Klimek P.E.,Director
Division of Water Quality
Coleen H. Sullins, Deputy Director
Division of Water Quality
March 26, 2004
Mr. Allan Rappuhn, Managing Member
Canebreak, LP
PO Box 220
Florence, AL 35631
Subject: Request for Additional Information
Stormwater Project No. SW8 040124
Canebreak Apartments
New Hanover County
Dear Mr. Rappuhn:
The Wilmington Regional Office received a Stormwater Management Permit Application
for Canebreak Apartments on January 20, 2004. 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 either delineate all wetlands on site, disturbed or undisturbed, or note on
the plans that none exist.
2. Since Mr. Kenneth White is your consultant, and is providing information
regarding this application, please complete Section VII on page 4 of the
application.
3. Please delineate the single overall- drainage area to the pond. It appears from the
post -runoff pond data tabulation that only 4.34 acres is draining to the pond,
while 5.25 acres has been reported on the supplement and is used in the pond
sizing calculations.
4. There appears to be runoff entering this project from the adjacent Manassas and
Tatum Family properties, as well as from the single family lots to the south.
Please either provide a means for this runoff to bypass the pond, or include these
numbers in the pond's drainage area and impervious area at 90% build -out.
5. The runoff from all of the proposed built -upon area, including the backs of all the
buildings and access drives, must either be directed into the pond or a separate
engineered treatment system must be provided. It appears from the drainage
area sheet that areas 13 and 15, which contain built -upon area, will not be
directed into the pond.
6. Please provide a list of wetland species to be planted on the 6:1 shelf.
7. Please add a note to the plans that all roof drainage must be directed to the
forebay of the proposed pond.
N. C. Division of Water Quality 127 Cardinal Drive Extension [phone] Customer Service C*
Wilmington Regional Office Wilmington, NC 28405 [phone] Fax [phone] iNCDENR

Mr. Rappuhn
March 26, 2004
Stormwater Aoolication No. SW8 040124
8. Please add a typical building detail showing dimensions, and identifying all
covered decks or stairs, sidewalk, patios, etc.
9. Please specify a trash rack for the outlet structure. Maximum openings are 4
inches square.
10. The basin diagram on page 3 of the supplement indicates that the permanent
pool elevation is 42.26, while page one of the supplement and the plans report
that the permanent pool elevation is 35.40. Please correct and revise.
Additionally, the cleanout depths have been reported as elevations instead of
depths. Based on a 5.4' deep pond, the cleanout depth is 4.05'. Please make the
appropriate corrections and resubmit.
Please note that this request for additional information is in response to a preliminary
review. The requested information should be received by this Office prior to April 26,
2004, 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 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].
Sincerely,
04--)z�z"
Linda Lewis
Environmental Engineer
RSSlad: S:IWQSISTORMWATIADDINFO120041040124.mar04
cc: Kenneth White, P.E.
Linda Lewis
Page 2 of 2

McKEAN
A R C H I T E
May 6. 2004
NCDENR
Wilmington Regional Office
127 Cardinal Drive Extension
Wilmington, NC 28405
(Courier 04-16-33)
910/395-3900
FAX [phone]
&A
C T S
TES
.L—L C
IMA 112004
Re: Stormwater Application No. SW8 040124
Linda Lewis:
Included are the revised forms and plans for the Stat Permit for Canebreaic
Apartments. If you have any questions. call me at (334) 272- 4.
Sincerely,
Bruce Taylor
2815-B Zelda Road, Montgomery, Alabama 36106, Telephone [phone], Facsimilie [phone]

Drainage Summary
for
Canebreak Apartments
Located at
Lullwater Drive
Wilmington, North Carolina
I. Project Description
The project consists of construction of multi family residential units and associated
sitework on 5.25-acre tract located off Lullwater Drive in Wilmington, NC. The project
will be constructed in one phase. The site is currently vacant. Construction will include
approximately 32 units, drives, water and sewer utilities, and concrete sidewalks.
2. Pre -Construction Site Conditions
Site is a relatively flat piece of property with ditches running along the east side of the
property. These ditches drain to the NE corner of the property. This water drains from
south to north eventually draining into Burnt Mill Creek.
3. Post -Construction Site Conditions
Site will have a wetpond located in and discharging to the NE corner of property. The
runoff from the site will be piped to this pond, and held in order to provide 90% removal
of total suspended solids without a vegetative filter. The ditch running down east side of
property will remain and be the discharge point from the wetpond.
4. Soil Erosion and Sedimentation
The site will be protected by silt fence on the east, west, south and north property lines.
Silt fence will be installed around all storm structures to prevent silt from entering storm
drain system. A construction entrance shall be installed to keep dirt to a minimum on
Lullwater Drive. Rip Rap will be installed at all discharging headwalls to prevent erosion.
The wetpond will be utilized for storage of silt buildup, and will be maintained properly
at all times. The site will be sodded and seeded at appropriate time to stabilize all graded
areas.
RECEIVED
AUG 0 6 2004
PRoa# 5�i? 6401Z4
III H+/r,,
• �N CA�qO
p4' •Frassio
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IN
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Canebreak Apartments
Wilmington, NC
03-532
Pre Runoff for a 10 Year Rainfall Event
Basin
Area (Acres)
c
I
Q (cfs
Offsite
5.25
0.450
6.50
15.36
Total 15.36
Unrestricted Post
Runoff for a 10 Year Rainfall Event
Basin
Area (Acres)
c
I
Q (cfs
Offsite
1.44
0.668
6.50
6.25
Pond
3.81
0.668
6.50
16.54
Total 22.79
Restricted Post Runoff for a 10 Year Rainfall Event
Basin
Area (Acres)
c
I
Q (cfs)
Offsite
1.44
0.668
6.50
6.25
Structure
1" Orifice=0.015
Primary Weir=0.39
NIA
0.41
Total 6.66

Canebreak Apartments
Wilmington, NC
03-532
Pre Runoff for a 50 Year Rainfall Event
Basin
Area (Acres)
C
I
Q cfs
Offsite
5.25
0.450
7.50
17.72
Tota 17.72
Post Runoff for a 50 Year Rainfall Event
Basin
Area (Acres)
C
I
Q cfs
Offsite
1.44
0.668
7.50
7.21
Pond
3.81
0.668
7.50
19.09
Total 26.30
Restricted Post Runoff for a 50 Year Rainfall Event
Basin
Area (Acres)
C
I
Q cfs)
Offsite
1.44
0.668
7.50
7.21
Structure
1" Orifice=0.015
Primary Weir=0.39
Secondary Weir=1.50
1.91
Total 9.12

Primary weir calculator
Given Input Data:
weir Type ....................... Rectangular
Equation ....................... Suppressed
solving for ..................... Flowrate
Depth of Flow ................... 2.6500 in
coefficient ..................... 0.6000
Height .......................... 2.6500 in
computed Results:
Flowrate ........................
0.3885 cfs
Full Flow .......................
0.3885 cfs
velocity ........................
1.5079 fps
width ...........................
14.0000 in
Area ............................
0.2576 ft2
Perimeter .......................
19.3000 in
wet Perimeter ...................
19.3000 in
wet Area ....................
0.2576 ft2
Percent Full ....................
100.0000

secondary weir calculator
Given Input Data:
weir Type ....................... Rectangular
Equation ....................... Suppressed
solving for ..................... Flowrate
Depth of Flow ................... 2.6500 in
coefficient ..................... 0.6000
Height .......................... 2.6500 in
computed Results:
Flowrate ........................ 1.4984 cfs
Full Flow ....................... 1.4984 cfs
velocity ........................ 1.5079 fps
width 54.0000 in
Area ............................ 0.9937 ft2
Perimeter ....................... 59.3000 in
Wet Perimeter ................... 59.3000 in
Wet Area .................... 0.9937 ft2
Percent Full .................... 100.0000 %

Design Calculations
Stormwater Treatment Facilities
for
Canebreak Apartments
located in
Wilmington, N.0
1. PROJECT DESCRIPTION
The Project consist of a proposed 32 unit apartment complex located on a 5.25 Ac. tract in Wilmington, N.C.
2. COMPUTE POND AREA REQUIRED
a. Compute Percent Impervious:
Impervious Areas:
On -Site Buildings
On -Site Streets and Parking
N/A
On -Site Sidewalks
Other on -site
Off -site
Sub -Total 0 93,046
FUTURE
Total 0 93,046
Total Area Drainage to Pond:
Percent Impervious =
0.561 or 56.1 %
Total
33,831 SF
44,015 SF
0 SF
15,200 SF
0
0
93,046 SF
0 SF
93,046 SF
_65x 66 SF
b. Compute Pond Surface Area
Using Surface Area to Drainage Area Ratio Chart for 85% TSS Removal (copy attached) and
assuming g ,54 foot pond depth:
SA/DA = = ; , ,. 99 % (interpolated)
Therefore:
Surface Area = SA/DA x Drainage Area
4,813 SF say ; r6800 SF

c. Compute Minimum Pond Dimensions
Assume rectangular shape with 3:1 Length (L) to Width (W) Ratio:
Length = 142.83 feet
Width = 47.61 feet
Site conditions, however, dictate:
Length = "I-F 7,-1,910 feet
so, Width (avi 60.0 feet
Actual LIW = 3.2
3. DETERMINE VOLUME TO BE CONTROLLED FROM 1" STORM
Using Schuler "Simple Method":
Rv = 0.05 + 0.009(I) where I = percent impervious
Rv = 0.555 in/in
Control Volume = Design Rainfall x Rv x Drainage Area
Control Volume = 7,670 CF say:: `8000 CF
4. DETERMINE REQUIRED STORAGE DEPTH
Assume: 3:1 side slopes
solving for depth (d) by trial & error:
d = 1.13

5. DETERMINE ORIFICE SIZE
Control Volume must be drawn down over a 2 day - 5 day period.
Using orifice equation, solve for Diameter (D) that results in 3-1/2 day period:
D = (Q / 0.026 (h).$) 5
Where: Q = (Control Volume / 3.5 days x 86,400 sec/day)
= 0.026 cfs
h=d/2
= 0.57
Solving for D:
D = 1.16 Use C,,,11771 00 "pipe
Actual Drawdown with actual drawdown pipe diameter (using orifice equation):
Q= 0.020 cfs
Draw Down Period = 4.74 days OK, < 5.0
6. SELECT OUTLET STRUCTURE DIAMETER
Size outlet structure such that depth of 010 flow <1.0 feet:
Using Rational Formula (Q=CIA) where:
Cimper
Cpery = =�:0'2
Ccum = 0.7
110 = ` U5-0� inlhr
A = 3.81 ac
Q 10 = 16.54 cfs
Assuming 1/2 circumference is used as weir and using
Francis Formula (0=3.331-1-11'5) to solve for L such that H = 1.0:
L = 4.97 Feet
Use 36 inch diameter outlet structure
7. DETERMINE Q10 STAGE
Q 10 = 16.54 cfs
Using Francis Formula (Q=3.33LH' 5) solve for H:
H10 = 1.04 feet

8. DETERMINE Q100 STAGE (ELEV. OF EMERGENCY SPILLWAY)
Using Rational Formula (Q=CIA) where:
Ccum = 0.67
1100 = ,54- &, 7 inlhr
A = 3.81 ac
Q100 = 21.63
Using Francis Formula (Q=3.33LH'*5) solve for H:
H100 = 1.24 feet
9. DETERMINE 0100 STAGE OVER EMERGENCY SPILLWAY (TOP BERM ELEV.)
Assume primary spillway blocked (i.e., emergency spillway to accommodate Q100)
Emergency spillway shall be a broad crested earthern weir designed to pass 100 year storm.
Using broad crested weir equation H = (QICw x L)2r3
where: Q = Q100 21.63 cfs
Cw = 3.0
Length = °-Km `:f+50 feet
H = 0.28 feet
10. FORESAY SIZING
Compute Actual Pond Volumes (using average end method):
Main Bay Volume:
Pond Bottom
Bottom Veg Shelf
Normal Pond
Main Bay Volume =
Forebay Volume:
Pond Bottom
Normal Pond
Forebay Volume =
Total Pond Volume =
Avg
Incr.
Incr.
Cum.
Elevation Area SF
Area SF
Depth (FT)
Vol CF
Vol CF
=m30 00 F. ' 2 4381
n,
34"00 __" 4'7.42
3,590
4.00
14,360
14,360
ry35.40,.jf 7,823
6,283
1.40
8,795
23,156
23,156 CF
Elevation Area SF Area SF Depth (FT) Vol CF Vol CF
30.00
35 40 ,� 3;244i 1,936 5.40 10,454 10,454
10,454 CF
33,610 CF
Forebay Volume equates to 31.1 % of Total Volume

Temp. Storage Volume: Elevation Area SF Area SF Depth (FT) Vol (CF) Vol CF
Normal Pond 35.40 11,067
Temp. Pond Level 36.53 12;62_ 11,847 1.13 13,387 13,387
Temp. Pool Volume = 13,387 CF
11. SUMMARY
Pond Elevations:
Top Berm (minimum)
H= 0.26
100-Yr. Flood
H100 = 1.24
10-Yr. Flood
H10 = 1.04
1-inch Storage
storage depth = 1.13
Permanent Pool
pond depth = 5.4
Pond Bottom
12. WET DETENTION BASIN SUPPLEMENT
Basin Bottom Elevation
30.00
Perm. Pool Elevation
35A0
Temp. Pool Elevation
36.53
Perm Pool Surface Area
11,067 SF
Drainage Area
3.81 AC
Impervious Area
2.14 AC
Perm. Pool Volume
33,610 CF
Temp Pool Volume
13,387 CF
Forebay Volume
10,454 CF
SA/DA
2.9
Diameter of Orifice
1.00
Design Rainfall
ill
Design TSS Removal
90%
Relative Actual
8.04
38.04 26
7.77
37.77 (emerg. weir elev)
7.57
37.57
6.53
36.53 (primary weir elev)
5.40
35.40 (invert out elev)
0 �0:00

FILE MODE
769� MEMORY TX
* * * COMMUNICATION RESULT REPORT ( JUL.30.2004
OPTION
REASON FOR ERROR
E-1) HANG UP OR LINE FAIL
E-3) NO ANSWER
ADDRESS(GROUP)
-
e-3342725464
P. 1
8:11AN )
TTI NCDENR WIRO
RESULT PAGE
--------------------P--lf1
OK
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A OAUEN
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Michael F. Easley, Governor
FAX COVER SHEET
Date: July 29, 2004
To: H. Kenneth White, P.E.
Company: H. Kenneth White & Asoc,
FAX #: [phone]M 54(o4
William G. Ross, Jr., Secretary
Alan W. Klimak, P.E., Director
No. of Pages: 1
From: Linda Lewis
Water Quality Section - Stormwater
FAX # [phone]
Phone # [phone]
DWQ Stormwater Project Number: SW8 040124
Project Name: Canebreak Apartments
MESSAGE:
Mr. White:
- The Division received previously requested information regarding the subject application on
May 11, 2004. The application is still incomplete. Please provide the following items prior to
August 29, 2004„to continue the review;
I�
1. Please add a dimensioned building detail for the smnllAr hiiiirlinn tha nm,ohn ��a 4k.,

�, Al
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Michael F. Easley, Govemor
William G. Ross, Jr., Secretary
Alan W. Klimek, P.E., Director
FAX COVER SHEET
Date: July 29, 2004 No. of Pages: 1
To: H. Kenneth White, P.E. From: Linda Lewis
Company: H. Kenneth White & Asoc.. Water Quality Section - Stormwater
FAX #: 334-272- " 54(A- FAX # [phone]
Phone # [phone]
DWQ Stormwater Project Number: SW$ 040124
Project Name: Canebreak Apartments
MESSAGE:
Mr. White:
The Division received previously requested information regarding the subject application on
May 11, 2004. The application is still incomplete. Please provide the following items prior to
August 29, 2004,,to continue the review:
ff
1. Please add a dimensioned building detail for the smaller building, the gazebo, and the
shuffleboard area.
2. The orifice calculation is not correct. It appears that you are using the average head
based on the 1" storage depth of 0.67'. This is not correct. The temporary pool depth you
have specified on the plans is 1.13' above the permanent pool, therefore, the average head
is in the neighborhood of .56', not .34'. However, please continue to use a control volume
that equates to the 1" volume. If you provide an outlet weir at elevation 36.07, then you can
use an average head of .34' to size the orifice, but since the "primary weir" in the riser is set
at 36.53, you need to use a .56' head. The 1" volume is the volume to be draw down in 2-5
days, in both situations.
3. 1 must have missed this item on the last review- please add the dimensions of the
permanent pool contour, including straight lines, arcs, etc.
RSSIarl: S:IWQSISTORMWATIADDINF0120041040124.ju104 '
Wilmington Regional Office
127 Cardinal Drive Extension, Wilmington, North Carolina 28405
Phone: [phone] FAX [phone] Internet: h2o.enr.state.nc.us
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