SW8060150_COMPLIANCE_20060508 (2)

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
DOC TYPE
El CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
COMPLIANCE EVALUATION INSPECTION
DOC DATE
�p��l � I
WYYMMDD

Pennit No. 56U yo(oo f so
(to be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form may be photocopied for use as an original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes an application form, a wet detention basin
supplement for each basin, design calculations, and plans and specifications showing all basin and outlet
stnictiixe detaaZs. ' _ ._.... , .. ,.. ,... .. ............._ .
L PROJECT INFORMATION
Project Name: 'Sotrttv�ell_ Woo-6 S� h ca t i ntin
Contact Person: Phone Number. (et 1 o i 2p2 - (900
For projects with multiple basins, specify which basin this worksheet applies to: _ L3 AIR A ti
elevations I�Ijs
Basin Bottom Elevation • 1� 3(oPft-
Permanent Pool Elevation fL
Temporary Pool Elevation ft.
areas
Permanent Pool Surface Area H o , 3i o s4. ft.
Drainage Area S. 1 s ac.
Impervious Area . is- ac.
volumes
Permanent Pool Volume cu. it
emporary4PoolyVvlume 33;53� --cu--ft.
Forebay Volume Z 75-0 cu. ft.
Other parameters
SA/DAI
Diameter of Orifice
Design Rainfall
Design TSS Removal
Z. Io
in.
in.
Jo %
(door of the basin)
(elevation of the orifice)
(elevation of the discharge structure overflow)
(water surface area at the orifice elevation)
(on -site and off -site drainage to the basin)
(on -site and off -site drainage to the basin)
(combined volume of main basin and forebay)
rtvo7ume-detain.ed dove the peror)
(approximately 20% of total volume)
(surface area to drainage area ratio from DWQ table)
(2 to S day temporary pool draw -down required)
(minimum 85% required)
Form SVVU-102 Rev 3.99 Page I of 4

Footnotes:
When using the Division SA/DA tables, the correct SA(DA ratio for permanent pool sizing should be computed based upon the
actual impervious % and permanent pool depth. Linear 'interpolation should be employed to determine the correct value for non-
standard table entries.
In the 20 coastal counties, the requirement for a vegetative filter may be waived if the wet detention basin is designed to provide
90% TSS removal. The NCDENR BMIP manual provides design tables for both 85% TSS removal and 90% TSS removal.
II. REQUIRED ITEMS CDECKLLST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual
(N.C. Department of Environment, Health and Natural Resources, February 1999) and Administrative Code
Section: 15 A NCAC 214.1008.
initial in the space provided to indicate the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. If a requirement has not been suet, attach justification.
Applicants Initials
v a. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet)-
i,J� _ b. The forebay volume is approximately equal to 2001b of the basin volume.
l S c- The temporary pool controls runoff from the design storm event_
IWSL-- d. The temporary pool draws down in 2 to 5 days.
I1JS'f _ _ e. If required, a 30-foot vegetative filter is provided at the outlet (include non -erosive flow
calculations)
ESL f_ The basin length to width ratio is greater than 3:1.
Lt�SL g. The basin side slopes above the permanent pool are no steeper than 3:1.
4.�SL h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail)-
_ L-psL - _ i. Vegetative cover above the permanent pool elevation is specified.
_ o, %- j. A trash rack or similar device is provided for both the overflow and orifice.
L k. A recorded drainage easement is provided for each basin including access to nearest right-
of-way.
L L If the basin is used for sediment and erosion control dung construction, clean out of the
basin is specified -prior to -use as a wet detention basin.
L m. A mechanism is specified cecill drain the basin for maintenance`- - • _ . .
��L�_._....�. - _ ~-- --�ifid which w
--- -- -- ---- or an emergency.
M. WET DETENTION BASIN OPERATION .AND MAINTENANCE AGREEMENT
The wet detention basin system is defined as the wet detention basin, pretreatment including forebays and the
vegetated filter if one is provided.
This system (check one) 0 does aes no incorporate a vegetated filter at the outlet.
This system (check one) 0 does oes no incorporate pretreatment other than a forebay.
Form SVVU-102 Rev 3.99 Page 2 of 4

Maintenance activities shall be performed as follows:
1. After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition.
b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs
within 2 to 5 days as designed.
2. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow vegetative
cover to Maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.
4. Remove accumulated sediment from the wet detention basin system semi-annually or when depth is
reduced to 7517b of the original design depth (see diagram below). Removed sediment shall be disposed
of in an appropriate manner and shall be handled in a manner that will not adversely impact water quality
(i.e. stockpiling near a wet detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.
When the permanent pool depth reads �feelti�the main pond, the sediment shall be removed.
Y. X� ftfw
When the permanent pool depth reads feet in the forebay, the sediment shall be removed_
BASIN DIAGRAM
(fill in the blanks)
Permauent Pool Elevation ` 1L . o
Sediment Re oval EL 3'i • Z 75 0
-------------- - Sediment Removal Elevation 3 CJ 75%
Bottom Ele ation Up • O %------------- -
- 25%
FOREBAY MAiN FOND
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm_
6. If the basin must be drained for an emergency or to perforin maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
Form SWU-102 Rev 3.99 Page 3 of 4

7. All components of the wet detention basin system sham be maintained in good working order.
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
charges to the system or responsible party.
Print name:_ CG_1K�lC/
Title:_ 2R?:Sn S� `(_ _ .
Address: 1 c_M 1 of 6:70 "� f-� C, ,a S 0 �
.iZZ�s!
Signature:
Date:_ 0
Note. The legally responsible party should not be a homeowners association unless more than 50% of the lots have been sold and
a resident of the subdivision has been named the president.
I, 1` P c�wl f �% _ a Notary Public for the State of _ , jo Y h ►'�
County of 1\j P. VU fla o V j&L" , do hereby certify that V I ' G cSi k k 0 - —
personally appeared before me this i � �'`'' day of —2101D, and acknowledge the due
execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal,
µ. Skit.
o 1
SEAT.
My commission expires_ Qjjd '57-4t , 20 t 1
Form SVW-102 Rev 3.99 Page 4 of 4

5

Permit No. aAj IF 0(p t 54
(to be provided by DWQ)
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
71is farm may be photocopiers for use as an original .
DWQ Storrnwater Management PIau Review:
A complete stor'mwater management plan submitwl includes an application form, a wet detention basin
supplement _for each basin" design calculations, and plans. and specifications showing all basin and outlet
..� ........ � __ .. _.
L PROJECT INFORMATION
Project Name: �J_ W✓ r, e.r W o a s .�u 12C� , Y
Contact Person: ; k : kkc, _ Phone Number: (ra 10) 242 -- Z00
For projects with multiple basmi s, specify which basin this worksheet applies to: W.D R 5' 3
elevations
Basin Bottom Elevation 33. O ft-
Permanent Pool Elevation -59 . O ft.
Temporary Pool Elevation Sal It ft.
areas
Permanent Pool Swface Area (a ` t 13 O sq. ft.
Drainage Area -qS-. 7P ac.
Impervious Area 13 • G (a ac.
volurnes
Permanent Pool Volume
--empcjo� Volume
Forebay VoInme
Other parameters
SAMA 1
Diameter of Orifice
Design Rainfall
Design TSS Removal 2
29 2 89 0 cu. ft.
co. ft.
(floor of the basin)
(elevation of the orifice)
(elevation of thy: discharge structure overflow)
(water surface area at the orifice elevation)
(on -site and off -site drainage to the basin)
(on -site and off -site drainage to the basin)
(combined volu►ne_of pwin.basin and forebay)
-(�b�uriie r�etni�a7�ove-the perri�nerif pool)
(approximately 20% of total volume)
(surface area to drainage area ratio from DWQ table)
(2 to 5 day temporary pool draw down required)
(minimum 85% required)
Form SW-102 Rev 3.99 Page 1 of 4

Footnotes:
When using the Division SAIDA tables, the correct SAIDA ratio for permanent pool sizing should be computed based upon the
actual impervious % and pennanent pool depth. Linear interpolation should be employed to determine the correct value for non-
standard table entries.
In the 20 coastal counties, the requirement for a vegetative filter may be waived if the wet detention basin is designed to provide
90% TSS removal. The NCDENR BMP manual provides design tables for both 85% TSS removal and 90% TSS removal.
D. REQU (ZED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual
(N-C. Department of Environment, Health and Natural Resources, February 1999) and Administrative Code
Section.: 15 A NCAC 2H .1008.
Initial in the space provided to indicate the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stornnwater Managerrxent Permit
Application Form, the agent may initial below. If a requirement has not been met, attach justification.
Applicants Initials
i)s l-- • _ a- The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
U.2) b. The forebay volume is approximately equal to 20% of the basin volume_
LO c. The temporary pool controls runoff from the design storm event.
SL d- The temporary pool draws down in 2 to 5 days.
_1> e. If required, a 30-foot vegetative filter is provided at the outlet (include non -erosive flow
calculations)
�. �. f. The basin length to width ratio is greater than 3: L
_ - g. The basin side slopes above the permanent pool are no steeper than 3:1.
W h_ A submerged and vegetated perina ter shelf with a slope of 6:1 or less (show detail).
i. Vegetative cover above the permanent pool elevation is specified.
_lb�_ j_ A trash rack or similar device is provided for both the overflow and orifice.
1AL k. A recorded drainage easement is provided for each basin including access to nearest right-
of-way.
1. If the basin is used for sediment and erosion control during construction, clean out of the
basin is specified Prior to use as a wet detention basin.
rn. A J z echariisrn is specified which will drain the basin for maintenance or an emergency.
M. WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The wetdetention basin system is defined as the wet detention basin, pretreatment including forebays and the
vegetated filter if one is provided.
This system (check one) 0 does 0 es not
This system (check one) 0 does 0 oes not
incorporate a vegetated filter at the outlet -
incorporate pretreatment other than a forebay.
Fonia SWU-102 Rev 3.99 Page 2 of 4

Maintenance activities shall be performed as follows:
After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet detention basin system for sediment accumulation, erosion, trash accumulation,
vegetated cover, and general condition-
b- Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs
within 2 to 5 days as designed.
2. Repair eroded areas immediately, re -seed as necessary to maintain good vegetative cover, mow vegetative
... cover to.mai. train a rnaximttm-height-of six. inches; and -remove ifasli as heedet3=
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc_) quart-;rly to
maintain proper functioning_
4. Remove accumulated sediment fxorn the wet detention basin system semi-annually or when depth is
re&ced to 75% of the origiu3al design depth (see diagram below)- Removed sediment shall be disposed
of ill an appropriate .manner and shall be handled in a manner that will not adversely impact water quality
Ci.e_ stockpling near a wet detention basic or stream.; etc.).
'the measuring device used to determine the sediment elevation: shall be such that it will give an acccu-ate
depth Breading and not readily penetrate into accumulated sediments.
When the permanent pool depth reads q• S feet in the main pond, the sediment shall be rernoved.
Wbm the permanent pool depth reads !Y. 5— feet in the forehay, the sediment shall be removed.
BASIN DIAGRAM
(fill in the blanks)
0 Permanent Pool Elevation 3 1
Sediment Re oval EL �� S 75 0
---- Sediment Removal Elevation 75%
BottomEle^2s%
FOREBAY MAJN POND
5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.
6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minin ized to the maxi num extent practical.
Forms SWU-102 Rev 3.99 Page 3 of 4

7. All components of the wet detention basin system shall be maintained in good working order.
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.
Print name: V;
Title: D W n er-
Address: PCB S,x r73G5 Wlminct-6 NC 254OC-:;,
Phone:_ 2(02 ^ Do Cr IU - 3 g'3 - Z o
Signature: _ —
Date:�f��3 �
Note: The legally responsible party should not be a homeowners association unless more than 50%a of the lots have been sold and
a resident of the subdivision has been named the president.
_ [`l f1 Q� �f • E—ro I mo- . a Notary Public for the State of 1J0 r,�h CA=�M 1
County of 1I e. W 46 A o vex✓ _ , do hereby certify that w V I C_
personally appeared before me this I '� day of Ai,ayf 4� a , and acknowledge the due
execution of the forrgobag wet entiort basin maintenance mquirements. Witness my hand and official seal,
40. Avb�
0 TA
f
y AVB C,
s" VER Go ,.�
SEAL
My corlmission expires �Giyr, _o?`� . a'-LO 1
Form SWU-102 iRev 3.99 Page 4 of 4

«B»
In accordance with Title 15 NCAC 2H.1000, the Coastal Stormwater Management Regulations, deed
restrictions and protective covenants are required for High Density Residential Subdivisions where
lots will be subdivided and sold and runoff will be treated in an engineered stormwater control facility.
Deed restrictions and protective covenants are necessary to ensure that the development maintains a
"built -upon" area consistent with the design criteria used to size the stormwater control facility.
I, _Vik Sikka , acknowledge, affirm and agree by my signature below,
that I will cause the following deed restrictions and covenants to be recorded prior to the sale of any lot:
1. The following covenants are intended to ensure ongoing compliance with State Stormwater
Management Permit Number_SW8 060150 as issued by the Division of Water Quality
under NCAC 2H.1000.
2. The State of North Carolina is made a beneficiary of these covenants to the extent necessary to
maintain compliance with the stormwater management permit.
3. These covenants are to run with the land and be binding on all persons and parties claiming
under them.
4. The covenants pertaining to stormwater may not be altered or rescinded without the express
written consent of the State of North Carolina, Division of Water Quality.
5. Alteration of the drainage as shown on the approved plan may not take place without the
concurrence of the Division of Water Quality.
6. The maximum allowable built -upon area per lot is _4000 square feet. This allotted amount
includes any built -upon area constructed within the lot property boundaries, and that portion of
the right-of-way between the front lot line and the edge of the pavement. Built upon area
includes, but is not limited to, structures, asphalt, concrete, gravel, brick, stone, slate, coquina
and parking areas, but does not include raised, open wood decking, or the water surface of
swimming pools.
7. All runoff from the built -upon areas on the lot must drain into the permitted system. This may be
accomplished through a variety of means including roof drain gutters which drain to the street,
grading the lot to drain toward the street, or grading perimeter swales to collect the lot runoff
and directi Lsyste
nto a component of the stormwater collection system. Lots that will naturally
drain into f are not required to provide these additional measures.
Signature: Date: 17 n
, C4 I (ee rn rh r �1-G�� , a Notary Public in the
State of K10041) County of e VV Po_" VZ;'
do hereby certify that Vi S4 k ka _._.._.. ,... personally appeared
before me this the day of ^ kAau.3(` , 20 00 , and acknowledge
the due execution of the foregoing instrument. Witness my hand and official seal,
SEAL
Sig ture
M.,, 5
My Commission expires warn La.� a 4 a D 11` Mif
�� A �G ��
yqH vg�4Go�},,a

CIVET DETENTION POND ANALYSIS
PROJECT #: SW8 060150.sepO6
PROJECT NAME: Summerwoods Subdivision
Pond 1 Pond 2
Receiving Stream: Middle Swamp
Classification:
Index Number:
Onsite DA, sf=
25.95
Offsite DA, sf =
0.00
Total Drainage Area:
1130382.00
Built -Upon Area
Lots, sf=
264000.00
Streets, sf=
90864.00
Clubhouse, sf=
SW
Other
Total Built -upon Area: 354864.00
Surface Area
% impervious
31.39%
Design Depth, ft:
6.00
TSS (85% or 90%):
90
SA/DA ratio
1.67%
Req. Min. Surface Ares
18874
Volume Calculations
Design Storm, inches:
1
Rational Cc=
0.44
Rational Volume, cf:
41679
Rv =
0.333
Min. Req. Volume=
31325
Bottom Elevation=
36.00
Permanent Pool Elev=
42.00
Perm Pool Area=
40390.00
Design Pool Elevation=
42.80
Design Pool Area=
43450.00
Total Volume Prov. =
33536.00
Forebay Volume
Permanent Pool Vol.=
160170,00
Req. Forebay Volume=
32034
Prov. Forebay Volume:
32750.00
Percent= (22>%>18)
20%
KIN
0.00
#DIV/O!
#DIV/O!
#DIV/O!
1
#DIV/O!
#DIV/01
#DIV/O!
#DIVI01
0.00
0
#DIV/O!
FILE NAME: S:1WQSIPOND1060150.sepO6.WK1
REVIEWER: L. Lewis
Original Run Date: July 17, 2006
Last Modified: 26-Sep-06
Pond 3 Pond 4 Pond 5 Pond 6
45.70
0.00
1990692.00
404000.00
162184.00
27000.00
2000.00
595184.00
29.90%
6
90
1.60%
31770
1
0.43
71392
0.319
52933
33.00
39.00
64130.00
39.90
67900.00
59413.50
292890.00
58578
64545
22%
0.00 0.00 0.00
0.00 1 0.00 1 0.00
#DIV/O! #DIV/O!
#DIV/O! #DIV/0!
#DIV/O! #DIV/O!
#DIV/O!
#DIV/0!
#DIV/0!
#DIVIO!
#DIV/O!
#DIV/O!
#DIV/O!
#DIVIO!
#DIV/O!
#DIV/O!
#DIV/O!
#DIV/0!
#DIV/O!
#DIV/O!
#DIVIO!
0.00 0.00 0.00
0 0 0
#DIV/O! #DIV/O! #DIV/01

{
Pond 1
Drawdown OrificetWeir
Avg. Head, ft =
0.34
Average Flow Q2, cfs
0.181
Average Flow Q5, cfs
0.073
Q2 Area, sq. in. =
9.33
Q5 Area, sq. in. =
3.73
No. of Orifices
1
Orifice Diameter, in.=
3.
Orifice Area, sq. in. =
7.069
Weir Height, inches=
Weir Length, inches=
Weir C =
11.355
Weir U, eff. length=
-0.067
Avg. Flowrate, Q, cfs =
0.137
Drawdown, days = 2.6
Pond 2
Pond 3
Pond 4
Pond 5
Pond 6
0.00
0.37
0.00
0.00
0.00
#DIVIa!
0,306.
#DIVIO!
#DIV/O!
#DIVIO!
#DIVIa!
0.123
#DIVIO!
#DIVIO!
#DIVIa!
#DIVIa!
15.13
#DIVIO!
#DIVIO!
#DIVIO!
#DIVIa!
6.05
#DIVIO!
#DIV/O!
#DIVIO!
1
4
0.000
12.566
0.000
0.000
0.000
#DIVIO!
12.460
#DIVIO!
#DIVIO!
#DIVIO!
0.000
-0.073
0.000
0.000
0.000
0.000
0.254
0.000
0.000
1 0.000
#DIVIa!
2.4
#DIVIOI
#DIVIO!
I #DIV/01

0
DESIGN NARRATIVE FOR HIGH DENSITY TREATMENT OF STORMWATER
AT SUMMERWOODS SUBDIVISION
BOLIVIA, BRUNSWICK CO., N.C.
Revised August, 2006
TABLE OF CONTENTS
1.0 PROJECT DESCRIPTION
2.0 SITE DESCRIPTION
3.0 ADJACENT PROPERTY
4.0 DRAINAGE CONSIDERATIONS
5.0 EROSION CONTROL CONSIDERATIONS
6.0 CONSTRUCTION SCHEDULE
7.0 VEGETATION PLAN
8.0 MAINTENANCE PLAN
APPENDIX
IMPERVIOUS AREA TOTALS
STORM PIPING CALCULATIONS
DETENTION POND SIZING CALCULATIONS
0 p
PE 0=7 a
at
/ENE Q. 1�
4 0
.SJS 68+'0* 13
Summer Woods Subdivision
May, 2006

1. Project Description: The Summer Woods Subdivision is a proposed project to
be develop 83 acres from woodland to residential in Bolivia in Brunswick County. The
land disturbing activity associated with the project will consist of clearing and grubbing
of trees, clearing existing drainage swales, grading of the site, and sediment and erosion
control measures such as a silt fence, gravel construction entrance, and wet detention
basins. The wet detention basins will act as sediment basins during construction but will
be sized for 90% TSS removal of impervious area runoff. Also included in the project
will be storm piping, water lines, and sewer lines, and paved roads with curb and gutter.
A community area will also be built with clubhouse, tennis, and swimming pool with
appropriate parking areas. The total area which will be disturbed for this project is 27.2
acres.
2. Site Description: The project site is in Bolivia, Brunswick Co., NC, located
directly to the west of where Galloway Road intersects with Old Ocean Highway,
Highway 17 Business. The property on which the development will take place is
currently owned by Vik and Ashley Sikka.
On site soils consist mainly of Goldsboro and Lynchburg, with some Muckale_e. These
soils are mainly loamy, fine sands.
There are existing wetlands onsite, approximately 6 acres.
New construction onsite will consist of paved roads with curb and gutter, curb inlets,
storm piping, and detention ponds. Also included will be a gravity sewer collection
system and a water distribution system.
General slope of the site is from center to west and east to the wetland areas.
Land use in the vicinity is residential and rural agricultural.
3. Adjacent Property: The areas adjacent to the project site are mostly
residential areas and rural agricultural.
4. Drainage Considerations: Drainage calculations to determine the size of storm
piping is attached in the appendix — Storm Piping Calculations. The project site
is graded so that storm water drains into strategically placed curb inlets. From
the curb inlets, storm water will empty into a network of storm pipes which drain
into several onsite storm water wet detention ponds. The storm pipe network
empties into -the detention pond below the -permanent pool elevation.
Calculations showing the sizing of the stormwater detention pond are shown in the
attached appendix — Detention Pond Sizing Calculations. The ponds are designed to
receive a Total Suspended Solids (TSS) removal of 90% and based on 6 foot depth for
two ponds and 5' depth on one pond. With 90% TSS there is no need for a vegetative
filter. The required temporary storage volume was determined using the Schueler
Method and basing calculations on a 1" rainfall event. Then the permanent pool volume
is determined based on the permanent pool surface area and the depth of the pool.
Then 20% of that volume is to be used for the forebay volume. -
Next the orifices were sized at 3" in diameter to keep the drainage time of the 1 inch
storm event between 2 and 5 days. A principal spillway was designed to drain storm
Summer Woods Subdivision
May, 2006

water that rises above the temporary pool elevation. It was sized using the excess
runoff created from pre and post development for the 25 year storm. An emergency
drainage spillway was sized to handle the same flow as the principal spillway, and will be
one foot above the temporary pool elevation.
5. Erosion Control Considerations: The following erosion control measures are
used on this project:
Temporary Gravel Construction Entrance/Exit
To prevent sediment from leaving the site, temporary gravel construction entrances
should be installed where the project entrance falls onto Galloway Road. For
dimensions and specifications, see construction details.
2. Land Grading
The existing slope of the site is from center to west and east towards the back of
the property. Most of the disturbed areas on the site will drain into curb inlets
which will empty into stormwater piping and drain into onsite detention ponds.
3. Silt Fence
Silt fence should be installed prior to clearing and grading activities. Silt fence
should be checked routinely. If needed, silt fence should be cleaned and replaced
if damaged. See Construction Detail for dimensions and specifications.
4. Inlet Protection
Inlet protection consisting of a small portion of silt fence surrounding proposed curb
inlets will be utilized to prevent sediment from entering the drainage system. See
Construction Detail for dimensions and specifications.
5. Detention Pond
Detention ponds will be built to control sediment from leaving the site. See
Construction Detail for dimensions and specifications.
6. Temporary Rock Check Dam
Rip rap dams constructed at discharge points of the temporary construction
ditches. These check dams will serve as temporary sediment traps until the
detention ponds are constructed. See Construction Detail for dimensions and
specifications.
6. Construction Schedule:
1. Obtain plan approval and other applicable permits.
2. Hold pre -construction meeting at least one ;meek prior to beginning construction.
3. Install temporary construction entrance/exits.
4. Before clearing and grading of the site, install silt fencing and clean and replace as
necessary.
Summer Woods Subdivision
May, 2006

5. Build onsite detention ponds.
6. Check existing swales and clear as necessary.
7. Begin clearing and grading of the site.
8. Construct onsite curb inlets with inlet protection.
9. Install storm piping,
10. Install sewer and waterlines and pave new roadway.
11. All erosion and sediment control practices will be inspected bi-weekly and after each
rainfall event. Needed repairs will be made immediately.
12. After the entire covered area is stabilized, all temporary measures will be removed
and permanent vegetative repairs to be completed.
7. Vegetation Plan:
1. After complete stabilization of the entire covered area, top cover soils will be
roughened by making 1 "-2" deep grooves perpendicular to the slope.
2. Spread lime (agricultural limestone) evenly over the area at a rate of 1.5 tons/acre;
spread 10-10-10 fertilizer at a rate of 1000 lb/acre and incorporate into the top 6" of
soil.
3. Loosen surface prior to applying seed.
4. Broadcast seed at recommended rates.
5. Rake seed into the soil and lightly pack to establish good contact.
6. Mulch with 4000 Ihlacre grain straw or equivalent and anchor by weighted farm disc
set nearly straight or other mulch anchoring tool.
7. Mow as needed and refertilize in late winter or early spring by topdressing with 10-
10-10 fertilizer.
8. Graded surfaces shall not be exposed without grass coverage for more than 15
days._ If grades are not complete and exposure is more than 15 days, temporary
seed with rye grain at 50 lb/acre.
8. Maintenance Plan:
1. Contractor shall maintain all sedimentation and erosion control devices during
construction.
2. All devices shall be checked after each rain event and weekly. Repairs shall be
made immediately when detected.
3. Any deficiencies shall'be brought to the immediate attention of the Engineer.
Summer Woods Subdivision
May, 2006

Seed Types and Application Rate I Schedule
Temporary Seeding
Grass Type
Amount/ 1000 SF
Time of Seeding
Initial
Rye Grain
1-2 Ibs
Nov. —Jan.
25 Ibs 10-10-10
Brown Top Mullet
1-2 Ibs
June— Aug.
25 Ibs 10-10-10
Permanent Seeding
Grass Type
Amount
Time of
Initial
Fertilization 1
Fertilization 1
Fertilization 1
11000
Seeding
1000 sf
1000 sf
1000 sf
sf
Maintenance
maintenance
maintenance
Burmuda,
1-2 Ibs
Apr. - 1
25 Ibs
March -April
Each 4-8
Aug. -Sept.
Common
June
10-10-10
12lbs
Weeks
12lbs
10-10-10
1-2 Ibs N.
10-10-10
Fescue, Tall
5-7 Ibs
Sept. —
25 Ibs
Feb -March
May & Dec.
Sept. -Oct.
(Kentucky
Oct.
10-10-10
12 Ibs
% to 1 lb. n.
12 Ibs
31)
Feb. —
10-10-10
10-10-10
Oct.
Sericea
1-2 Ibs
March —
25 Ibs
Feb -March
'/2 to 1 lb. N.
NIA
Lespedeza
Apr.
10-10-10
Slo es
END OF PLAN
Summer Woods Subdivision
May, 2006

;�': .
-�'�...
L

Right Angle Engineering, P.C.
DETENTION POND SIZING CALCULATIONS
Summerwoods Subdivision
Wet Detension Basin #1 Design
Drainage Area =
25.95
acres
Impervious Area =
8.15
acres
Percent Impervious =
31.4%
Pond depth =
6
ft
TSS removal =
90%
SAIDA =
2.10%
(No vegetative filter required)
Minimum Required Surface Area at Permanent Pooh
=
0.021
'
Minimum Required Volume (Schueler Method, see calculations);
Rv = 0.05 + 0.000
(31.39)
_
Volume = (1"112")
0.333
'
Approx. Permanent Pool Dimensions =
;_ 400.0 ".
by
Actual Surface Area Provided at PP =
40390
>
Need at Least
31325
H3
Elevation of Temporary Pool =
42
+
Surface Dims of Temp. Pool =
600
by
Actual Surface Area at
42.8
=
Temporary Storage Volume Provided =
33536
H3
Forebay Volume - Minimum 20% of Permanent Pool Volume
Volume by average area =
40390
sl @ PP
Actual Permanent Pool Volrirne =
160170
cf
Forebay Volume Required =
(.2-
160170
Forebay Depth =
5
ft
Surface Area at bottom of forebay(Elev, 37') =
4500
sf
Surface Area at top of forebay(Elev. 42') =
3600
sf
Forebay Volume Provided =
32750
of
Orifice Sizing
Q2 =
31325
1
Q5 =
31325
1
Choose a 3" Circular Orifice, Average Head =
0.181 cfs >
Choose a 4" Circular Orifice, Average Head =
u.181 cfs <
Therefore, use a 3" Orifice
25.95
0.3325
25.95
43560 =
-23738
@
of storage/
40390
Therefore, use
0.80
H =
80.00
43450
sf
actual vs. design of
43560 = _23738_•„ sf
31325 tt3
40000 sf
Elev. 42 it
0,78 ft
0,80 ft
42.8 H
31325 ft'
and 13000 SF at bottom
= 32034 cf
172800 = 0.181 cfs (Flowrate required for a 2 day drawdown)
432000 = 0.073 cfs (Flowrate required for a 5 day drawdown)
a, = 0.06481
a3 = 0,025922
(,80-(112)'(2in112Y2=
0.338 ft
dia (in) = 3 a = pi(r^2)
0.0491 sf
Q = Ca(2gh)A.5 =
0.1373 cfs
0,1373 cfs >
0.073 cfs
(.80-(112)"(4inl12Y2=
0.317 ft
dia (in) = 4 a = pi(r'2)
0.08727 sf
Q = Ca(2gh)A.5 =
0.23645 cfs
0.2365 cfs -
0.073 cfs
Page 1

Right Angle Engineering, P.C. DETENTION POND SIZING CALCULATIONS
Summerwoods Subdivision
Pre -Development 25 Year Storm
by Rational Formula
Q=CIA =
C=
0.3
1 =
7.14 inlhr
To =
10.00 min
A =
28.0 ac
Q = CIA =
55.61 cfs
Post -Development 25 Year Storm
by Rational Formula
Q=CIA =
C =
0.420
1 =
7.14
To =
10.00
A =
26.0
Q = CIA =
77.80 cfs
Difference between Pre and Post Development
Q = 22.20 cfs
Size Outlet Pipe
D = 16(Qnifs^.5))^(318
Qpost =
77.80 cfs
s =
0.75%
n =
0.013
D (theoretical) =
40.2 in
D (actual) =
42.0 in
Size Emergency Spillway
impervious 0.00%
pervious = 100.00%
I (in/hr) = g/(h+T) for T=5 to 120 minutes
impervious 31.39%
pervious= 68.61%
1 fin/hr) = g/(h+T) for T=5 to 120 minutes
_ Channel Lining: Rip Rap
n= 0.030
1.00 ft. 1 S= 1.00%
3 Q Mannings (cfs)= 104.12 Max
--20.0 ft-�
Length= 20 ft
Velocity-- 4.53 fits
Depth with Freeboard= 1.00 ft
Page 2

.0 Right Angle`Ertgineering, P.C. DETENTION POND SIZING CALCULATIONS 9/22/2006
Summerwoods Subdivision
Wet Detension Basin #3 Design
Drainage Area =
45.70
acres
DA-2 plus DA-3
Impervious Area =
13,66
acres
DA-2 plus DA-3
Percent Impervious =
29,9%
Total Combined
Pond depth =
6
ft
TSS removal =
90%
SA/DA =
1.60%
(No vegetative filter required)
Minimum Required Surface Area at Permanent Pool:
0.016
45.70
Minimum Required Volume (Schueler Method, see calculations):
Rv = 0.05 + 0.009
(29.89)
=
0,3190
Volume = 0"112 )
0.319
45.70 43560 =
Approx. Permanent Pool Dimensions =
480.0
by
125.0 =
Actual Surface Area Provided at PP =
64130
>
31851 @
Need at Least
52918
ft3
of storage/ 64130
Therefore, use
Elevation of Temporary Pool =
39
f
0.90 h =
Approx. Surface Dims of Temp. Pool =
600
by
125.00 avg.
Actual Surface Area(by CAD) at
39.9
=
67900 sf
Temporary Storage Volume Provided =
59414
ft3
actual vs. design of:
Forebay Volume - Minimum 20% of Permanent Pool Volume
43560 = �`,31851" sf
52918 ft'
60000 ' sf
Elev. 39 it
0.83 it
0.90 ft
39.90 ft
52918 ft'
Volume by average area =
64130 sf @ PP
and
33500 SF at bottom
Actual Permanent Poo$ Volume =
292890 cf
Forebay Volume Required =
(.2' 292890
} =
58578 cf
Forebay Depth =
5 It
Surface Area at bottom of forebay(Eiev, 33') =
7600 sf
Surface Area at top of forebay(Elev, 39') =
18218 sf
Forebay Volume Provided =
64545 of
Orifice Sizing
Cie =
52918 !
172800
= 0.306
cis (Flowrate required for a 2 day drawdown)
Q5 =
52918 !
432000
= 0.122
cfs (Flowrate required for a 5 day drawdown)
az =
0.10217
85 =
0.040869
Choose a 3" Circular
Orifice, Average Head =
(.90-(112)'(2in112)12 =
0.388
ft
dia (in) = 3
a = pi(r^2)
0.0491
sf
Q = Ca(2gh)^,5 =
0.1471
cfs
0.306 cfs
>
0.1471 cfs
>
0.122
cfs
Choose a 4" Circular
Orifice, Average Head =
(.90-(1/2)'(4in112)12 =
0.367
ft
dia (in) = 4
a = pi(r^2)
0.08727
sf
Q = Ca(2gh)^.5 =
0.25444
cfs
0.306 cfs
>
0.2544 cfs
>
0.122
cfs
Therefore, use a 4" Orifice
RECEIVED
SEP 2 2 2006
DWQ
PROJ #
0
jr
S
PE 7 .��.
t
�5)Fa
` a
�'°ANE L1 ,,# zz _� 6
04*1P r a 0";° o q
Page 1

1 Right Angid Engineering, P.C. DETENTION POND SIZING CALCULATIONS 9/2212006
Summerwoods Subdivision
Pre -Development 25 Year Storm by Rational Formula
Q=CIA =
C =
0.3
1 =
7.14
inlhr
Tc =
10.00
min
A =
45.7
ac
Q = CIA =
97.93
cfs
Post -Development 25 Year Storm
by Rational
Formula
Q = CIA =
C =
0.409
1 =
7.14
Tc =
10.00
A =
45.7
Q = CIA =
133.58
cfs
Difference between Pre and Post Development
Q = 35,65 cfs
Size Outlet Pipe
D = 16(Qnf(s".5))A(3iB)
Qpost =
133.58 cfs
S =
0.50%
n =
0.009
D (theoretical) =
46.3 in
D (actual) =
48.0 in
Size Emergency Spillway
impervious 0.00%
pervious= 100.00%
I fin/hr) = gl{h+T) for T=5 to 120 minutes
impervious 29.89%
pervious= 70.11%
I (in/hr) = g/(h+T) for T=5 to 120 minutes
_ Channel Lining: Rip Rap
n= 0.030
1.0 1 S= 1.00%
3 Q Mannings (cfs)= 79.63 Max
�15.0 f!—►�
Length= 15 ft
Velocity-- 4.42 ftls
Depth with Freeboard- 1.00 ft
Page 2

Outlet Protection Sizing
Q (flowrate)
Depth (ft)
Do (in)
La (ft)
W (ft)
3`Do (ft)
Outlet Protection - Into
Detention Pond 1
38.90
1
30
15
17.50
7.5
Outlet Protection - Out
of Detention Pond 1
77.80
1.5
42
25
28.50
10.5
Outlet Protection - Into
Detention Pond 2
29.59
1
30
15
17.50
7.5
Outlet Protection - Out
of Detention Pond 2
59.18
1
36
25
28.00
9.0
Outlet Protection - Into
37.21
1
30
15
17.50
7.5
Detention Pond 3
Outlet Protection - Out
133.60
1.5
43
30
34.00
12.0
of Detention Pond 3
3'Do
W =Do+La
1