SW6111201_HISTORICAL FILE_20111222

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

e��w
NCDENR
North Carolina Department of Environment and Natural Resources
Pat McCrory John E. Skvarla, III
Governor Secretary
June 23, 2014
Mr. Jarrod E. Hilliard
Hilliard Engineering, PLLC
749 Walker Road
Sanford, North Carolina 27331
Subject: Lightwood Subdivision Phase I -- Minor Revision
Doc Brown Road, Raeford, Hoke County 28376 OCT 1 6
Stormwater Permit No. SW6111201
Dear Mr. Hilliard: ---
The Stormwater Permitting Unit received a request for a plan revision for Stormwater Management
Permit Number SW6111201 on June 18, 2014. The revision includes minor changes in the plans for
stormwater management. It has been determined that a formal permit modification is not required
for the revisions. We are forwarding you an approved copy of the revised plan for your files.
Please be aware that all terms and conditions of the permit issued on December 29, 2011, remain in
full force and effect. Please also understand that the approval of this revision to the approved plans
for the subject State Stormwater Permit is done on a case -by -case basis. Any other changes to this
project must be submitted to and approved through the permitting authority prior to construction.
The issuance of this plan revision does not preclude the permittee from complying with all other
applicable statutes, rules, regulations or ordinances which may have jurisdiction over the proposed
activity, and obtaining a permit or approval prior to construction.
This project will be kept on file at the Fayetteville Regional Office. If you have any questions, or need
additional information concerning this matter, please contact Bill Diuguid at [phone]; or
[e-mail].
Sincerely,
Original Signed by William H. Diuguid
William H. Diuguid, AICP, Stormwater Plans Reviewer
for Tracy E. Davis, PE, CPM, Director
Division of Energy, Mineral and Land Resources
cc: SW6111201 File
ec: Brad Cole, Mike Lawyer, NCDENR DEMLR Land Quality Section, Fayetteville Regional Office
Division of Energy, Mineral, and Land Resources
Energy Section • Geological Survey Section • Land Quality Section
1612 Mail Service Center, Raleigh, North Carolina 27699-1612.919-707-9200 / FAX: [phone]
512 North Salisbury Street, Raleigh, North Carolina 27604 • Internet: hftp://portal.nodenr.org/webllr/
An Equal Opportunity 1 Affirmative Action Employer - 50% Recycled 110% Post Consumer Paper

TRANSMITTAL
/-.HILL-1ARD---------. =�--
ENGINEERING
FROM: Hilliard Engineering, PLLC
749 Walker Road, Sanford, NC 27332
PO Box 249, Sanford, NC 27331
[phone]
[e-mail]
TO: Bill Diuguid, Stormwater Permitting tJUN
L�E-;­AU.;0TY
Land Quality SectionDivision of Energy, Mineral and Land ResourcesINCDENR1612 Mail Service CenterRaleigh North Carolina 27699-1612
RE: Lightwood Subdivision -Modification to shape of Wet Pond #2
State Stormwater Permit No. SW6111201
�aXE ,y
Ct7fi-!t'--J>ve AROWgn3I RV - YEiwr /Z Z9
HE#: HC1401.300 gABFoa9 DATE: 9/16/14
�+�prow f 2/28/ZOZ/
MESSAGE:
Please find enclosed the following:
Two (2)-copies of wet pond #2 modification plans
Permit items were previously submitted with the original project permitted under Permit No.
SW6111201 and remain applicable to this project. This submission is for approval of a modified
shape to Wet Pond #2 in order to replace the previously designed baffle with an earthen one
while maitaning the same areas.
If you have any questions, or require additional information, please feel free to contact me at this
office.
Jarrod E. Hilliard, PE, CFM, President
Hilliard Engineering, PLLC OCT 1 6

C O CONSUL
U TINGENGINEERS
&ASSOCIATES
CONSULC ENGINEERS
P.O. BOX 1737
300 SOUTH WEST BROAD STREET
SOUTHERN PINES, NORTH CAROLINA 28387
PHONE: I-(910)-692-5616
FAX: [phone]
To: NCDENR -DWQ
Stormwater Permitting Unit
512 North Salisbury Street
Raleigh, NC 27604
The Following Item(s) :
LETTER OF TRANSMITTAL
Date: 12/21/2011 JJob No. HC1014
Ann. Robert Patterson, PE
Ref.: Li htwood Subdivision Phase I
We are sending you
Attat� hed
Under se ��^�Q
O Under separate cover VIA t//��( I�I:�T
O Shop Drawings Prints O Samples
O Copy of Letter Change Order O
J� ��a�
o Specifications `rtANOsftSNrER ,
rpR wry
NCH
Copies
Date
Project No.
Description
2
Sets of Revisal plans
2
One original and one copy of revised application
2
One original and one copy of revised deed restrictions
2
One on final and one copy of revised wet ponds calculations
I
Response letter
These are Transmitted as Checked Below
For Approval Approved as Submitted
t� For Your Use Approved as Noted
t� As Requested Returned for Corrections
O For Review and Comment f�
Remarks:
O Resubmit for Approval
Submit for Distribution
0 Return Correeted Prints
t� Prints Returned After Loan to Us
Copy To:
Signed: \`W✓�, `/ ill `'
Frank Wanko, Project Designer

�o r
NC®ENR
North Carolina Department of Environment and Natural Resources
Beverly Eaves Perdue
Governor
Mr. Thomas K. Goodwin, PE
Hobbs, Upchurch & Associates, PA
300 SW Broad Street
Southern Pines, NC 28387
Dear Mr. Goodwin:
Division of Water Quality
Coleen H. Sullins
Director
December 12, 2011
Subject: Request for Additional Information
Stormwater Project No. SW6111201
Lightwood Subdivision Phase 1
Hoke County
Dee Freeman
Secretary
The Division of Water Quality Central Office received a Stormwater Management Permit Application
for the subject project on December 2, 2011. 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 address the following items concerning the DA table in IV.10. of SWU-101:
a. The deed restriction form shows each lot limited to 2,800 sf (46 lots x 2,800 =
128,800), however the DA table appears to have used 3,000 sf for each lot (93,000
+ 45,000 = 138,000 = 46 lots x 3,000).
b. The impervious area for Doc Brown Rd. should be shown as off -site in the table
instead of existing.
c. DA 1 should show the portion of Phase 2 draining to pond 1 as off -site area. The
future BUA for this captured portion of Phase 2 must be stated and included as off -
site impervious area in the table.
2. The top of the both pond risers are not consistently shown on C-14, C-15, D-6, and D-9. The
temporary pool elevation (TPE) used for the drawdown calculations should be the next
available outlet above the drawdown orifice. It appears this is the value used on D-9, in the
calculations, and supplement; but different on the other sheets. Also, the emergency
spillways for both ponds are at an elevation below the top of the risers on C-14.
3. Please provide a detail for the permanent baffle in pond 2.
4. Please provide a fence detail for the sections of fence that cross over the drainage swales
to show how flow will not be impeaded/bypassed.
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 January 12, 2012, 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
Wetlands and Stormwater Branch
One
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
NOrthCarOhna
Location: 512 N. Salisbury St. Raleigh, North Carolina 27604
Phone: [phone] FAX: [phone] Customer Service: 1-877-6236748
�aturallr�
Internet: wwvi.ncwaterquality.org
An Equal Opportunity 1 Afniative Action Employer

Mr: Thomas K. Goodwin, PE
SW6111201- Lightwood Subdivision Phase 1
December 12, 2011
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.
All revised original signed documents must be returned or new originals must be provided. Copies are
not acceptable. Any revised calculations or plans must be sealed, signed, and dated; and have a
revision date shown. Please reference the State assigned project number SW6111201 on all
correspondence. If you have any questions concerning this matter please feel free to call me at (919)
807-6375, or at [e-mail].
Sincerely,
Robert D. Patterson, PE
Environmental Engineer
Stormwater Permitting Unit
cc: SW6111201 File
Joseph C. Poole
ec: Mike Lawyer- Fayetteville Regional Office
Page 2 of 2

�iEffLRJ fU )Ro4a00-r T"g//e"a"J
Application Completeness Review
E� First Submittal ❑ Re -submittal Date Received: /2 2 Date Reviewed: iz s i By Bill Diuguid
Development/Project Name w— S u P Aga 1
Receiving stream name Ro „r(, ��� e Classification: R
For post-constrdction requirements, a program will be deemed compliant for the areas where it is
implementing any of the following programs: WS-I, WS-II, WS-III, WS-IV, HOW, ORW, Neuse River Basin
NSW, Tar -Pamlico River Basin NSW, and the Randleman Lake Water Supply Watershed Nutrient
High Density Projects that require a 401/404 within an NSW require 85% TSS, 30% TN and 30% TP removal.
T&E Species (Goose Creek, Waxhaw Creek or Six Mile Creek Water Sheds): N
Latitude and Longitude: 3S OD 92 /J/ — 79 7-0 73 W Jurisdiction C
Project Address: JDQ r— A,' UJ/J 'Z
Engineer name and firm -r �� OAp -. /a-okb s Upahmt, I- AssCciA4-,s 1 uc.
r[lul IM y I —,.I � _
Is the project confirmed to be in the State MCI Storm ater Permit jurisdiction . Yes or El No
❑ Low Density (no curb and gutter) Low Density with curb and gutter outlets ❑ High Density ❑ Other
yAYg,s.� 401/404 impacts to surface waters, wetlands, and buffers (add language to cover letter and/or add info letter)
rri BUA 0. S
V Check for $505.00r included
V Original signature (not photocopy) on application
G✓Legal signature (Corporation-VP/higher, Partnership -General Partner/higher, LLC-member/manager, Agent).
a WAfer—
If an agent signs the application, a signed letter of authorization from the applicant must be provided which
includes the name, title, mailing address and phone number of the person signing the letter.
ref'�or subdivided projects, a signed and notarized deed restriction statement
rY Sealed, signed & dated calculations
u/'Correct supplement and O&M provided for each BMP on site (check all that were provided & number of each)
❑ Bioretention
❑ Dry Detention Basin
o Filter Strip
❑ Grass Swale
❑ Infiltration Basin
❑ Infiltration Trench
❑ Level Spreader
o Permeable Pavement
❑ Restored Riparian Buffer
❑ Rooftop Runoff Management
❑ Sand Filter
05tormwater Wetland
Wet Detention Basin
❑ Low Density
❑ Curb Outlet
❑ Off -Site
❑ NCDOT Linear Road
v /Two sets of sealed, signed & dated layout & finish grading plans with appropriate details
u:r arrative Description of stormwater management provided
a Soils report provided
o' Wetlands delineated or a note on the plans or in the accompanying documents that none exist on site and/or
adjacent property
o�Details for the roads, parking area, cul-de-sac radii, sidewalk widths, curb and gutter;
V_ Dimensions & slopes provided
9,--Drainage areas delineated --l!rP'ervious and impervious reported for each 43-Areas of high density
rgMP operation and maintenance agreements provided
Application complete ❑ Application Incomplete Returned: (Date)
c4es,
May 5, 2011 Revision, Bill Diuguid

HOBBS, UPCHURCH & ASSOCIATES
CONSULTING ENGINEERS
P.O. BOX 1737
300 SOUTH WEST BROAD STREET
SOUTHERN PINES, NORTH CAROLINA 28387
PHONE: [phone]
FAX: I -(9 t 0)-692-7342
To: NCDENR -DWQ
512 N. Salisbury St.
Raleigh, NC 27604
The Following Item(s) :
LETTER OF TRANSMITTAL
Dale: 12/1/2011 JJob No. IiC1014
Arm. Stormwatcr Pcrmittin Unit
Ref: Li htwood Subdivision Phase I
We are sending you
® Attached
O Under separate cover VIA
O Shop Drawings 0 Prints O Samples
O Copy of Letter O Change Order 0
0 Specifications
Copies
Date
Project No.
Description
2
One original and one copy of Application, O&M Agreement, Restrictions
1
Check for permit fees of $505.00
2
Sealed and Signed Supplements and Supporting Calcs for Wet Ponds
2
Sealed and Si ed sets of supporting information
2
Sets of Plans
These are Transmitted as Checked Below :
For Approval
t-1 Approved as Submitted
O Resubmit for Approval
O For Your Use
O Approved as Noted
O Submit for Distribution
O As Requested
o Returned for Corrections
O Return Corrected Prints
r-1 For Review and Comment 0
0 Prints Returned After Loan to Us
Copy To: Signed: i
Frank Wanko, Project Designer

:, /CI112 f
Wet Detention Basin
Computations
For
Lightwood Subdivision Phase 1
Hoke County, North Carolina
Prepared by:
Hobbs, Upchurch & Associates, P.A.
300 S.W. Broad Street
Southern Pines, NC 28387
November, 2011
Revised December, 2011

Permit No. S t✓6 ( 1 ) 2 Z� (
(to be provided by DWD)
NCDENR
Project name
Contact person
Phone number
Date
Drainage area number
020
F W Arg9O
/C
STORMWATER MANAGEMENT PERMIT APPLICATION FORM o
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
II,DESIGN'.INFORMATIONi;{,frOrrduu.°,ii�;:,,a!
Site Characteristics
Drainage area
Impervious area, post -development
%impervious
Design rainfall depth
Storage Volume: Non -SA Waters
Minimum volume required
Volume provided
Storage Volume: SA Waters
1.5' runoff volume
Pre -development 1-yr, 24-hr runoff
Post -development l-yr, 24-hr runoff
Minimum volume required
Volume provided
Peak Flow Calculations
Is the pre/post control of the lyr 24hr storm peak flow required?
1-yr, 24-hr rainfall depth
Rational C, pre -development
Rational C, post -development
Rainfall intensity: 1-yr, 24-hr storm
Pre -development 1-yr, 24-hr peak flow
Post -development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak flow control
Elevations
Temporary pool elevation
Permanent pool elevation
SHWT elevation (approx. at the pens. pool elevation)
Top of 10ft vegetated shelf elevation
Bottom of 10ft vegetated shelf elevation
Sediment cleanout, top elevation (bottom of pond)
Sediment cleanout, bottom elevation
Sediment storage provided
Is there additional volume stored above the state -required temp, pool?
Elevation of the top of the additional volume
16.67 %
1'.0'in
-:19,481`. ft3 OK
' 33,326; fta
OK, volume provided is equal to or in excess of volume required,
F7 Ycz- :(Y or N)
3.0;in
r.
1.- 0.30i(unitess)
0.40(unitless)
1.05 ft3/sec
1.39 ft3/sec
0.34 ft'Isec
'220.00 fmsi
':.:1218.00; fmsl
"
213.001fmsl
-,..218.50'. firs]
fmsi
i="•�-.217.50
-''213.00'fmsl
€-°:•;
.;.a:212.00. fmsi
1.00 it
e
Y3 (Y or N)
,
{
220.0!fmsl OK
Form SW401-Wet Detention Basin-Rev.&9r17109 Parts 1.811, Design Summary, Page 1 of 2

Permit No. SL✓c / I I Z-0 I
(to be provided by OWO)
Il.:DESIGN INFORMATION iYUkKVV"�r�, :�s�+;r. �r ' "t?«i'; f ,'^`'1,.,..''' i,,:ra,05
Surface Areas
Area, temporary pool
; �....-19,0401 ft'
Area REQUIRED, permanent pool
13,091 ih
SAIDA ratio
.. 1A2I(unitless)
Area PROVIDED, permanent pool, A._,,
..13,218; ft`
OK
Area, bottom of 10ft vegetated shelf, Am, a„ 3
s, = r, 10,687l ft
Area, sediment cleanout, top elevation (bottom of pond), A,a-
1; .:r : 4,542�ft`
Volumes
Volume, temporary pool
�`.'''<. 33,326' ft3
OK
Volume, permanent pool, V.-.
? 1x� " .37,774`ft3
Volume, forebay (sum of forebays If more than one forebay)
„7;808,ry3
Forebay % of permanent pool volume
20.7% %
OK
SAIDA Table Data
Design TSS removal
%
Coastal SAIDA Table Used?
Nr, ":'^'j (Y or N)
Mountain/Piedmont SAIDA Table Used?
Y ; (Y or N)
SAIDA ratio
1.12 (unitless)
Average depth (used in SAIDA table):
Calculation option 1 used? (See Figure 10-2b)
_
F �w; N' W.��,'�(Y or N)
Volume, permanent pool, Vr,,,,.
37,774 ft'
Area provided, permanent pool, A.,,
13,218 fl
Average depth calculated
i - ° _ [ft
Need 3 it min.
Average depth used in SAIDA, it., (Round to nearest 0.511)
n^3 ; "f it
Calculation option 2 used? (See Figure 10-2b)
�' .�.,Y(Y or N)
Area provided, permanent pool, A._P,,,
13,218 It'
Area, bottom of 10ft vegetated shelf, Am,_,,,
10,687 fit`
Area, sediment cleanout, top elevation (bottom of pond), A,y,,,
4,542 hz
'Depth' (distance b/vv bottom of 10ft shelf and top of sediment)
4.50 it
Average depth calculated
.,};` "" 9166ft
OK
Average depth used in SAIDA, it., (Round to nearest 0.5fl)
= `-` ,. : '. 3.51ft
OK
Drawdown Calculations
Orawdown through orifice?
Diameter of orifice (if circular)
Area of orifice (if -non -circular)
Coefficient of discharge (Co)
Driving head (H,)
Drawdown through weir?
Weir type
Coefficient of discharge (C.,)
Length of weir (L)
Driving head (H)
Pm -development 1-yr, 24-hr peak flaw
Post -development 1-yr, 24-hr peak flow
Storage volume discharge rate (through discharge onfce or weir)
Storage volume drawdown time
Additional Information
Vegetated side slopes
Vegetated shelf slope
Vegetated shelf width
Length of flowpath to width ratio
Length to width ratio
Trash rack for overflow & orifice?
Freeboard provided
Vegetated Alter provided?
Recorded drainage easement provided?
Capures all runoff at ultimate build -out?
Drain mechanism for maintenance or emergencies is:
I n.� 2.00-In
in 2
(unittess)
0.82 ft
;,, (Y or N)
sl(unitless)
(unitless)
ft3/sec
;;. A 0.21 ft3/sec
i.273;days OK, draws down In 2-5 days.
4.0!:1
OK
OK
OK
OK
OK
or N) OK
OK
or N) OK
or N) OK
or N) OK
Form SW401-Wet Detention Basin -Rev .8-9/17109 Pans I. & II. Design Summary, Page 2 of 2

Wet Pond No. 1 Supporting Calculations
Peak Inflow Calculations
Drairiag&Areal(A'),
1,168,849 SF
26.83 Acres -
1,115 SF
0.03 Acres
194,880 SF
4.47
Acres-

Lightwood Subdivision
Built Upon Area Calculations:
Sidewalks/Handicap Ramps:
14,598 sq.ft.
Pavement/Curb:
84,282 sq.ft.
Estimate Building/Lot: 3,000 sq.ft./lot
x 31 Lots 93,000 sq.ft.
Phase 2 Building/Lot: 3,000 sq.ft./lot
x 1 Lot 3,000 sq.ft.
Total Estimated Built Upon Area:
194,880 sq.ft. = 4.47 acres
Total Project Area:
1,168,849 sq.ft. = 26.83 acres
Total Project BUA Estimate:
16.67

Permanent Pool Storage Volume
Incremental
Total
Elev.
Area (s.f.)
Volume (cf.)
Volume (c.f.)
Depth (ft.)
212 Sediment Bottom
2,318
213 Sediment Top
3,236
3,729
3.729
1
214
4,222
4,750
8,479
2
215
5,278
5.841
14,320
3
216
6.403
7.000
21,319
4
217
7,596
3,953
25,272
4.5
217.5 Bottom Veg. Shelf
8,217
4,693
29,966
5
218 Perm Pool
10.556
13.218
7,253
7,253
0.5
218.5 Top Veg. Shelf
15,794
8,150
15,403
1.0
219
16,806
17,923
33,326
2.0
220 Top Temp. Pool
19,040
Forebay #1 Volume Provided
Incremental
Total
Elev.
Area (s.f.)
Volume (c.f.)
Volume (c.f.)
Depth (8.)
213 Sediment Bottom
1,030
214 Sediment Top
1,306
1,457
1,457
1
215
1.607
1.771
3,227
2
216
1,934
2.110
5,337
3
217
2.285
1,189
6,525
3.5
217.5 Bottom Veg. Shelf
2,470
1.283
7,808
4
218 Perm Pool
2,662
Surface Areas
Area Temporary Pool = 19,040 S.f.
Area Permanent Pool= 13.218 s.f.
Area Bottom of Vegetated Shelf = 10.687 s.f.
Area Sediment Cleanoul Top Elev. = 4,542 s.f.
Volumes
Temporary Pool Volume= 33,326 cf.
Permanent Pool Volume = 37,774 c.f.
Forebay Volume= 7,808 c.f.
Forebay Volume Percentage = 20.7%

ZI S70RMWATERBMP '�:. : r r I °Y<..�`•
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LightWood Subdivision VOLUME COMPUTATIONS
MINIMUM VOLUME REQUIRED.
USE SIMPLE METHOD, COMPARE TO DISCRETE SCS METHOD
Treatment Volume:
Control and treat the first 1.0 inches of rain
Additional Requirements:
No additional requirements
Watershed Size::;
��r26.63 �=.� acres
Percent Impervious Area.:(
16:67-:,_�- % Total Composite CN 58.00
Impervious Area:
4.47 acres
Pervious Area:
22.36 acres
Water Quality Storm:
1.0 inch
Hydrologic Soil Group:
.f;:=Avg: A� �� •� (Varies, See Composite HSG Computations)
Pervious Land Use CN.::.."„50}:-
(See Pre -Developed Composite CN Computations)
Impervious Land Use CN:
98
�v yRUNOFF
UETERMINATION:���i`�,rv,15,I":;ai��'a.�ait
NCDENR
Stormwater BMP Manual, Section 3.3
_Discrete SCS.Method t:, . .• _ ,_.r`•'..• , �' �..,.,.
PRECIPITATION (P):
1.00 inches (Water Quality Storm)
BREAKDOWN OF SOIL STORAGE (S):
Formula.' 5=1000/CN-10
Impervious (S):
0.204 inches
Pervious (S):
10.000 inches
BREAKDOWN OF RUNOFF (RIO):
Formula: R/0=(P-0.2`S)� /(P+0.8'S)
Impervious (R/0):
0.791 inches
Pervious (R/O):
0.111 inches
BREAKDOWN OF'FIRST FLUSH' (V):
Formula: V=Area `Runoff Depth
Impervious (V):
3.538 acre -inches
Pervious (V):
2.484 acre -inches
TREATMENT VOL. REQUIRED (Vraenr):
Formula: V rRear=Impervious V +pervious V
(VTaenr):
6.023 acre -inches
(VTREAT)�
Z1553 (t3
Sim le Method .,.`.. •,;.a:- .. . ._., ,: ,
Ia:
0.166728123 (Impervious fraction)
Re:
1.0 in (Water Quality Storm)
A:
26.83308081 acres (Watershed Area)
RUNOFF COEFFICIENT (Rv):
Formula: R v=0.05+0.9'l o
R,,:
0.200055311
TREATMENT VOL. REQUIRED (VTREAT):
Formula: V rREar=Ro `R v'A
(VTREAT):
19,486 ft3
(Vraenr):
5.368 acre -inches
USE: IVTREAT�•
F).023 acre -inches = 19,486 cu. ft

Lightwood Subdivision
WET DETENTION BASIN ORIFICE DRAWDOWN COMPUTATIONS
00 = Co X A x (2xgxHo)'rz
Where Ho H/3
and H=Temp Pool Elev.-Perm. Pool Elev+1/2 Orifice Diameter
Orifice Diameter: s:1y�iii2'i : ;'3 =i inches
Minimum Volume Required: x,:,;a,:19,487",+;t:,d. ft3
Temporary Pool Elevation Calculated x' �'220 e `.7 ft-MSL
Permanent Pool Elevation Provided: M, r+,', P2185a.. !' ft-MSL
CD ' ,0.590.,, `^,`
A: 0.022 sf
2g: 64,400 ft S2
H: 1.917 ft
Ho: 0.639 ft
Oo: 0.083 cfs
Dewatering Time: 2.732 days
(Min. Volume/Dewatering Rate)

Permit No. 5l•✓6! I ( Z.0 1
(to be provided by DWD)
NDA
A OF W ATFR
o2 OG
NCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted
The Required Items Checklist (Part III) must be printed, filled out and submitted along with all of the required information.
Project name Lightwood Subdivision M1 ,_
Contact person (- 4'::- c zr Thomas K. Goodwin, P.E.
,
Phone number 910-6925616 ^i-� * ?* , :•,'rat<n
gtt v:
Dale 9512011.
Drainage area number 12 3;_;
IC-OESIGN.INFORMATION;:'.t
Site Characteristics
Drainage area
Impervious area, post -development
%impervious
Design rainfall depth
Storage Volume: Non -SA Waters
Minimum volume required
Volume provided
Storage Volume: SA Waters
IS' runoff volume
Pre -development 1-yr, 24-hr runoff
Post -development 1-yr, 24-hr runoff
Minimum volume required
Volume provided
Peak Flow Calculations
Is the pre/post control of the 1yr 24hr storm peak flow required?
1-yr, 24-hr rainfall depth
Rational C, pre -development
Rational C, post -development
Rainfall intensity: 1-yr, 24-hr storm
Pre -development 1-yr, 24-hr peak flow
Post -development 1-yr, 24-hr peak flow
Pre/Post 1-yr, 24-hr peak flow control
Elevations
Temporary pool elevation
Permanent pool elevation
SHWT elevation (approx. at the perm. pool elevation)
Top of 10ft vegetated shelf elevation
Bottom of 1 Oft vegetated shelf elevation
Sediment cleanout, top elevation (bottom of pond)
Sediment cleanout, bottom elevation
Sediment storage provided
Is there additional volume stored above the state -required temp. pooh
Elevation of the top of the additional volume
20.36 %
e1.0:in
I'- ^�ar'.19,320`ry3 OK
E 15275(t3
3 OK, volume provided is equal to or in excess of volume required.
a,��,Y^s)(YorN)
3.0 in
^r " 0.33'(unifless)
+e 0.13iirdhr OK
0.47 Its/sec
0.60 ft3/sec
0.13 0/car
;i.^, -5i: 251.00 first
I 249.50'fmsl
r'.i';* 1,r' 245.50.fmsl
1=;:.'..:fir250.00'. fmsl
249.00 mist
244.01
"-''- a', 243.00', find
1.00 H
I
251.0, fmsl OK
Form SW401-Wet Detention Basin-Rev.8-9/17109 Parts 1.811. Design Summary, Page 1 of 2

Permit No. SW6 f i I Zn /
(to be provided by DWO)
I1.DESIGN .INFORMAT ION,., `.,+1, f1k.,-•;;n,v:G'+i1 .".e Wfl�' N-if" ;,:t ,.4„7stze17
Surface Areas
Area, temporary pool
Area REQUIRED, permanent pool
SA/DA ratio
Area PROVIDED, permanent pool, Ars,,
Area, bottom of 1 Oft vegetated shelf, Am ,
Area, sediment cleanout, top elevation (bottom of pond), A,.pa,,,
Volumes
Volume, temporary pool
Volume, permanent pool, V.-.
Volume, forebay (sum of forebays if more than one forebay)
Forebay % of permanent pool volume
SAIDA Table Data
Design TSS removal
Coastal SAIDA Table Used?
Mourf aiNPiedmont SAIDA Table Used?
SAIDA ratio
Average depth (used in SAIDA table):
Calculation option 1 used? (See Figure 10-2b)
Volume, permanent pool, Vr,..
Area provided, permanent pool, Ate,,,.
Average depth calculated
Average depth used in SAIDA, dv„ (Round to nearest 0.5ft)
Calculation option 2 used? (See Figure 10-2b)
Area provided, permanent pool, A._.
Area, bottom of 10ft vegetated shelf, A.,,,,
'14,152: f?
6,329 ft'
. 1.32'1(unitless)
7,7151 ft` OK
Si i'': .h'15;275 fit OK
20,986, ft'
f 3,904i ft3
18.6 % % OK
ii .N' ;(YorN)
Y, °" `I(YorN)
1.32 (unitless)
ge5:a`k;;.wNsn- (Y or N)
TOtli ft'
7,715 ft
'fl
tft
Y s'`((Y or N)
7,715 ft`
5,945 fl`
Need 3 It min.
Area, sediment cleanout, top elevation (bottom of pond), A..
1,501 fl
"Depth' (distance b/w bottom of 1 Oft shelf and top of sediment)
5.00 ft
Average depth calculated
3.57ift
OK
Average depth used in SAIDA, d., (Round to nearest 0.5ft)
#,,:"� :S: ks„ , 3.5; ft
OK
Drawdown Calculations
Drawdown through onfce?
_
Diameter of orifice (if circular)
," 1.50 in
Area of orifice (if -non -circular)
3 '`j'v " * 1` ".1In`
Coefficient of discharge (Co)
; `� * .0.59:(unitless)
Ddving head(H.)
t...'` ,;. 0.641ft
Drawdown through weir?
-((Y or N)
Weir type
,"r'.od..x ;:1; t ., (unitless)
Coefficient of discharge (C„.)
g<. _ ; _?(unitless)
-_
Length of weir (L)
y ft
Ddving head (H)
�z h ,; ft
Pre -development 1-yr, 24-hr peak flow
0:47 ft'Isec
Post -development l-yr, 24-hr peak flow
}_;'-`"`;, 0.60 fl'Isec
Storage volume discharge rate (through discharge orifice or weir)
-` 0' ft/sec
Storage volume dmwdown time
` 2.32 days
OK, draws dawn in 2-5 days.
Additional Information
Vegetated side slopes
1
OK
Vegetated shelf slope
10i:1
OK
Vegetated shelf width
w.-10.01ft
OK
Length of flowpath to width ratio
+i-"' , -" 4,:1
OK
Length to width ratio,.=
s.°;N2.5':1
OK
Trash rack for overflow 8 orifice?
`- Y.-',<,: (Y or N)
OK
Freeboard provided
{.; ''-"-';1 1.5ft
OK
Vegetated filter provided?
4�N f..T(Y or N)
OK
Recorded drainage easement provided?
g;, .`, ;,Y-: ::, (Y or N)
OK
Capures all runoff at ultimate build -out?
;- Y- ' ': ;(Y or N)
OK
Drain mechanism for maintenance or emergencies is:
:.Manual Pump'
Form SW401-Wet Detention Basin-Rev.9-9/17/09 Parts 1.811. Design Summary, Page 2 of 2

Permanent Pool Storage Volume
Incremental
Total
Elev.
Area (s.f.)
Volume (c.f.)
Volume (c.f.)
Depth (fl )
243 Sediment Bottom
890
2" Sediment Top
1,334
1.596
1.596
1
245
1.857
2.158
3,753
2
246
2,458
2.796
6,549
3
247
3,134
3.507
10,056
4
248
3,879
4.281
14.336
5
249 Bottom Vag, Shelf
4,682
2.746
17,082
5.5
249.5 Perm Pool
6,302
7.715
4.322
4.322
0.5
250.0 Top Veg. Shelf
9,571
5,204
9,526
1.0
250.5
11,246
5749
1"75
1.5
251 Top Temp. Pool
11,750
Forestry 01 Volume Provided
Incremental
Total
Elev.
Area (s.f)
Volume (c.f.)
Volume (c.f.)
Depth (ft)
243 Sediment Bottom
66
244 Sediment Top
167
240
240
1
245
313
407
647
2
246
500
613
1,259
3
247
725
854
2,113
4
248
982
1,123
3,235
5
249 Bottom Veg. Shelf
1,263
669
3,904
5.5
249.5 Perm Pool
1,413
Surface Areas
Area Temporary Pool = 11,750 s.f.
Area Permanent Pool = 7,715 sl.
Area Bottom of Vegetated Shelf = 5,945 s.f.
Area Sediment Cleanout Top Elev. = 1,501 s.f.
Volumes
Temporary Pool Volume = 15,275 c.f.
Permanent Pool Volume = 20,986 c f.
Forebay Volume= 3,904 c.f.
Forebay Volume Percentage = 18.6%