20070973 Ver 1_Stormwater Info_20070607

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• Stormwater Impact Analysis
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• South Park Village
• Holly Springs, NC
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Prepared for:
• Stephens Property Group, LLC
• ©Kimley-Hom and Associates, Inc., 2007
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• ~ Kimley-Horn
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and Associates, Inc.
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SOUTH PARK VILLAGE
HOLLY SPRINGS, NC
STORMWATER IMPACT ANALYSIS
Prepared for:
STEPHENS PROPERTY GROUP, LLC
7 PIEDMONT CENTER, SUITE 300
3525 PIEDMONT ROAD
ATLANTA, GA 30305
Prepared by:
KIMLEY-HORN AND ASSOCIATES, INC.
P.O. BOX 33068
RALEIGH, NORTH CAROLINA 27636
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REVISED: MAY 2007
APRIL 2007
KHA Project No: 011919012

TABLE OF CONTENTS
OVERVIEW
FIGURES
USGS QUADRANGLE MAP
SOILS SURVEY
PRE-DEVELOPMENT DRAINAGE AREAS
POST-DEVELOPMENT DRAINAGE AREAS
WATER QUALITY
NITROGEN CALCULATIONS
WETLAND DESIGN SUMMARY
WATER QUANTITY
POND PACK PRE VERSUS POST SUMMARY
POND PACK NODE DESIGN
POND PACK DESIGN STORMS
POND PACK TIME OF CONCENTRATION CALCULATIONS
POND PACK CURVE NUMBER CALCULATIONS
POND PACK POND VOLUMES
POND PACK SUMMARY OF POND AND OUTLET STRUCTURE

EROSION CONTROL CALCULATIONS
SOILS DATA
SEDIMENT BASIN DESIGN
RIP RAP CALCULATIONS
APPENDICES
CN VALUE TABLE
RAINFALL DEPTH/INTENSITY CHARTS

OVERVIEW
Background
This report is based on the results of a stonnwater impact analysis (SIA) performed for the project
known as South Park Village. The project is located between Avent Ferry Road and Ralph Stephens
Loop Road, on the south side of the NC Highway 55 bypass, in Holly Springs, North Carolina. The
subject site encompasses 39.11 acres of currently undeveloped land slated to consist of a retail
shopping center and associated parking areas, as well as the subsequently required stormwater
management facilities.
The proposed retail development located along the south side of the NC Highway 55 bypass will
require stormwater management facilities to treat stormwater for both water quality and quantity. As a
result of the existing topography, natural drainage patterns, and the routing of several existing culverts
which convey offsite runoff onto or across the site, two extended detention wetlands are proposed to
satisfy these requirements. These have been designed in accordance with the NCDENR regulations
and the Town of Holly Springs requirements to treat the first 1" of runoff and remove 85% of total
suspended solids (TSS). The larger of the two proposed extended detention wetlands will be placed
immediately adjacent to the existing wetland on the north side of the NC Hwy 55 bypass, and has
been designed to treat the bulk of the runoff from the project (134.1 acres) as well as the offsite runoff
which traditionally flowed into the existing wetland (f18.21 acres). Installation of a 60" pipe beneath
the NC Hwy 55 bypass will serve to convey the onsite runoff to this wetland system. Prior to reaching
the existing 48" culvert beneath the bypass, offsite runoff will be routed around the perimeter of the
site (rather than across it) before reaching the proposed extended detention wetland. To facilitate
maintenance, a gravel access road will be installed. The second, smaller, proposed extended detention
wetland will abut the existing wetland in the southeastern portion of the site. This wetland has been
designed to treat the remaining onsite runoff (f4.38 acres). Small areas located adjacent to the
existing and proposed wetlands, and those outside of the curb-line perimeter which contain no new
proposed impervious areas, will continue to drain directly to the existing wetlands as they did
historically.
Erosion Control
Erosion control measures have been designed in accordance with the Town of Holly Springs Erosion
Control Standards and Specifications and NCDENR requirements. Diversion ditches will be installed
to route sediment laden waters to sediment traps and skimmer basins, which will be sized to treat this
runoff from the land disturbance. Construction entrances will be installed prior to construction
commencement, as well as silt fence along the low sides of the site. Inlet protection will be installed
around all existing inlets and will be utilized for the proposed curb inlets and drop inlets

Soils
The Wake County Soils Survey indicates that onsite soils are comprised of various Appling gravelly
sandy foams, Faceville sand foams, and Rains fine sandy foams. These soils are all classified as
hydrologic soil group B.
Site Stabilization
After final grading is completed, permanent vegetation shall be applied in accordance with the
landscape plan for this site.
Stormwater Analysis
Runoff from the site currently drains, via several different routes, to one of two existing wetlands. The
primary recipient of runoff is the existing wetland located on the north side of the NC Hwy 55 bypass.
This wetland receives runoff from onsite via an existing 18" culvert (f3.18 acres), an existing 48"
culvert (f 19.54 acres), and an existing 12" culvert (6.65 acres}. Each of these culverts outfalls to the
existing stream/wetland on the north side of the bypass. In addition to the onsite runoff which flows
directly to the 48" culvert, several offsite areas flow to this culvert indirectly as well. These include
the area north of Avent Ferry Road (18.40 acres) which passes beneath the road through an existing
30" culvert and an area south of the project site (9.42 acres) which flows onto/across the site as
dictated by existing topography. Lastly, runoff from the area immediately adjacent to the northern
wetland (f3.94 acres) enters directly via overland flow. The existing wetland located along the
southeastern portion of the site receives the remainder of the stormwater runoff (f 11.68 acres). Points
of interest (POI's) were established to measure the discharge rates into these wetlands for comparison
with the proposed post-development conditions to demonstrate compliance with the required
parameters. POI-1 has been assigned to the existing wetland on the north side of the NC Hwy 55
bypass, and POI-2 to the wetland along the southeastern edge of the property.
Stormwater runoff from the proposed project will be directed to two extended detention wetlands.
Wetland 1, located adjacent to the existing wetland on the north side of the NC Hwy 55 bypass, has
been designed to treat the majority of the onsite runoff (f34.1 acres, 24.1 of which is impervious)
along with the offsite runoff which historically flowed to the existing wetland/stream (f 18.21 acres,
1.86 of which is impervious). Wetland 1 (1.8] acres at surface of permanent pool) has been designed
to treat the runoff from its constituent areas (f52.32 acres, 25.96 of which is impervious) and draw
down this treatment volume in 2.14 days. Impervious areas have been calculated based on the
estimated future build-out of the site. The point of analysis for peak discharge flows, POI-1, is
located adjacent to the wetlands on the north side of the bypass (See Drainage Map).Proposed
Wetland 2, which abuts the existing wetland on the southeastern portion of the site, has been designed
to treat the runoff from the remaining onsite area (f4.38 acres, 3.47 of which is impervious).
Impervious areas have been calculated based on the estimated future build-out of the site. Draw down

time for Wetland 2 (0.29 acres at surface of permanent pool) is 2.25 days. The point of analysis for
peak discharges for this area, POI-2, is located directly adjacent to these wetlands on the southeastern
edge of the property (see Drainage Map).
Pre vs. Post Summary Table

, 4 ~ ~. Storm Event (years) ~:
,
1 2 10` ~ ` 25
Discharge Rate (cfs)
Pre-development 17.79 29.96 75.04 124.82
POI-1
Post-develo ment 14.74 29.64 63.25 115.22
1 2 10 25
Pre-development 2.21 5.21 18.21 27.27
POI-2
Post-development 1.23 3.01 13.6 19.81
Water Quantity
Post-development peak flows from the site will not exceed pre-development rates for the required
storm events (lyr/24hr, 2yr/24hr, and l0yr/24hr). A 6' x 6' square concrete riser structure will be
installed in Wetland 1. Equipped with an orifice, two intermediate slot-weirs, and the horizontal grate
on top, this riser has been designed to control and pass all events up to and including the l0yr/24hr
storm. Larger storm events will be controlled by a 30' emergency spillway in conjunction with riser
structure. Please reference the Water Quantity section of the appendices for further details pertaining
to Wetland 1.
Wetland 2 will utilize a 4' x 4' square concrete riser structure which includes an orifice, one
intermediate weir, and the top-grate to control and pass all events up to and including the l0yr/24hr
storm. Larger storm events will be controlled by a 20' emergency spillway in conjunction with the
riser structure. Due to the decreased total drainage area which reaches the existing wetland (18.86
acres post-development compared to f 11.68 acres pre-development), peak discharge rates are
significantly reduced for all events up to and including the 100yr/24hr storm. Please reference the
Water Quantity section of the appendices for further details pertaining to Wetland 2.
Water Quality
The majority of the development will drain to the proposed stormwater extended detention wetlands,
which have been designed to mitigate the impacts of the development on stormwater quality and
quantity. The permanent pool for the wetlands will have a design depth of three feet in the areas
dedicated to deep pools.

The proposed extended detention wetlands will provide a Total Nitrogen removal efficiency of 40%
and 85% removal of Total Suspended Solids (TSS). Given the size and impervious cover of the area
occupied by South Park Village, the Nitrogen reduction provided by the extended detention wetlands
brings the total export to approximately 9.17 lbs/ac/yr. This abides by the NCDENR's "Stormwater
Best Management Practices" manual which states:
"The stormwater wetland is designed to provide 85% total suspended solid (TSS) removal
and to reduce nitrogen loading rates to below 10 lbs/ac/yr per the Neuse Stormwater Rule
(1 SA NCAC 2B .0235) of the "Neuse River Basin: Model Stormwater Program for Nitrogen
Control, "August, 1999.
The allowed Nitrogen export from the site is 3.6 lb/ac/yr, thus indicating that it will be necessary to
buy-down to the required level (at $330 per pound). Calculation of the amount required is shown
below:
(9.17 ]b/ac/yr-3.6 lb/ac/yr) x (43.106 ac) x ($330/lb) _ $71,854.68
The extended detention wetlands will have a variety of plant-life to aid in the reduction of Nitrogen.
These areas of the wetland will be broken down based on the following table.
High Low Forebay Deep
Marshes Marshes Pools
Wetland 1 37% 38% 11 % 14%
Wetland 2 35% 35% 15% 15%
Methods
The stormwater conveyance system was analyzed using "Autocad Land Desktop 2007 -Pipe Works."
Pre- and post-development runoff calculations have been completed using "Pond Pack," a Bentley
Systems software program that utilizes TR-55 methods of calculating time of concentration and SCS
methods of generating hydrographs.
Conclusion
Based on the analysis provided herein, the proposed stormwater management system is adequate to
meet to address the stormwater requirements of the Town of Holly Springs and NCDENR.

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Soil Survey of Wake County, North Carolina Southpark V~11age Soil Types
Map Unit Legend Summary
Wake County, North Carolina
Map Unit Symbol Map Unit Name
Acres in AOI Percent of AOI
r~gI32 Appbng ~.~ravelly sandy loam, 2 to 10.9
Ci percent slopes, tnnderately
erix3 ~1
AgC2 Appling gravelly sandy loam, 6 to 7.7
10 percent slopes, moderately
eroded
~1pC2 Applin~~ s~indv loam, 6 to ]0 12
percent slopes, moderately eroded
CnA Colfax sandy loam, 0 to 3 percent 6.4
slopes
F3I3~ Faceville sand~> login, ~ to 6 20.11
percent slopes, moderately eri?ded
FaC2 Faceville sandy loam, 6 to 10 9.0
percent slopes, moderately eroded
ti'ol3 Norfolk loam}' s~u~d, 2 to U 9.3
percent slopes
NoB2 Norfolk loamy sand, 2 to 6 0.2
percent slopes, moderately eroded
C)rI3? Orangcbur,~ loamy sand. 2 [0 6 5.5
percent slopes, nxxicratrly eroded
RaA Rains fine sandy loam, 0 to 2 23.3
percent slopes
~l'o:~ ~~%chaclkec and Bibb soils, 0 to 2 3.6
percent slopes, fn~gacntly t~ocxjed
10.5
7.6
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3. f~
USDA Natural Reso~RCes Web Soil Survey 1.1 1/23/2UU7
Gwsrrvafiuo Service National Cooperative Soil Survey Page 3 of 3

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/'~ Kimley-Horn
`! ~ and Associates, Inc.
Extended Stormwater Wetland Design Summary
Proposed Extended Detention Wetland #1
Project Information
Project Name: South Park Village
KHA Project #: 011919012
Designed by: JDA Date: 4/2/2007
Checked by: WAC Date: 4/11/2007
Revised by: MCP Date: 5/16/2007
Checked by: Date:
Design Resource: NCDENR -Stormwater Best Management Practices (April 1999)
NCDENR -Updated Draft Manual of Stormwater Best Management Practices (July 2005)
Site Information
Sub Area Location: Wetland 1
Drainage Area (DA) = 52.32 Acres
Impervious Area (IA) = 25.96 Acres
Percent Impervious (I) = 49.6
Required Surface Area
Permanent Pool Depth: 3 ft
SA/DA = 2.05 (85% TSS Removal via Pond)
Min Req'd Surface Area = 46,721 sf (at Permanent Pool)
Required Storage Volume (Water Quality):
Design Storm = 1 inch
Determine Rv Value = 0.05 + .009 (I) = 0.50 in/in
Storage Volume Required = 94,301 cf (above Permanent Pool)
Required Forbay Sizing
Required Volume = 20.00% of Permenant Pool
Permanent Pool Volume = 61,772 cf
Required Forbay Volume = 12,354
Ext. Wetland Surface Area Requirements:
Surface Area % of Approx. Surface
Depth of Perm. Pool Zone ID Permenant Pool Area (sf )
0" - 12" Marsh 70.00% 32,704
0" - 6" Low Marsh 35.00% 16,352
6" - 12" High Marsh 35.00% 16,352
12" - 36" Outlet Pool 15.00% 7,008
Summary of Proposed Ext. Wetland
Bottom of Pond Elevation = 427.00 ft
Permanent Pool Elevation = 430.00 ft
Temporary Pool Elevation = 431.35 ft
Top of Pond Elevation = 435.00 ft
Permanent Pool Surface Area = 74,547 sf (Elev = 430 )
Temporary Pool (water quality storage) = 103,543 cf (Required Volume = 94300.866 )
Area @ Top of Temporary Pool = 78,865 sf (Elev = 431.35 )
Side Slopes of Pond = 3 : 1
Volume of Forebay 19,371 cf (Required volume = 12354.35 )
Surface Area ratios:

De th of Perm. Pool
Zone ID Surface Area % of
Permenant Pool Approx. Surface
Area sf
0" - 12" Marsh 75% 56,149
0" - 6" Hi h Marsh 37% 27,821
6" - 12" Low Marsh 38% 28 328
12" - 36" Outlet Pool 14% 10,400
- Foreba 11% 7,832

Anti-Flotation Device
Riser Width = 6 ft
Riser Length = 6 ft
Top Riser Elev. = 432.15
Bottom Riser Elev. = 426.50 ft
Height of Riser = 5.65 ft
Area of Riser = 36.0 sf (Water Displaced)
Volume of Riser = 203.4 cf (Water Displaced)
Factor of Safety = 1.2
Weight = 12692.2 Ibs
Weight Req'd from Anti-Flotation Device = 15230.6 Ibs
V
5. 65

2.5 ft

'Weight of Riser = 3093.4 Ibs (Volume Riser Wall' Buoyant WtJ 7' x 7' Concrete Slab-
'
Additional Volume of Concrete Req'd = 138.6 cf (Buoyant Wt Concrete = (150-62.4) pcf)
Extend Riser = 2.5 ft
Volume of Riser Extension = 90.0 cf
Volume of Anti-flotation 7' x7' Concrete Slab = 49.0
Volume Provided = 139.0
h
i
Is the Anti-flotation Device Sufficient (yes/no)? Yes
139.0 > 138.6
'Assume 6" riser wall thickness with buoyant weight of concrete = (150-62.4) pcf

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Cam„ Kimley-Horn
~ and Associates, lnc.
Extended Detention Wetland 1
INCREMENTAL DRAWDOWN METHOD
Project Information
Project Name
KHA Project #
Designed by
Checked by:
Revised by
Checked by:
South Park Village
011919012
JDA Date: 4/2/2007
WAC Date: 4/11/2007
MCP Date: 5/15/2007
Date:
Water Quality Orifice
* Incremental Determination of Water Quality Volume Drawdown Time
Zone 3
Zone 2 U
Zone 1
Orifice Diameter (D) _
Cd =
Ei =
Zone 1 Range =
Zone 2 Range =
Zone 3 Range =
12.0 in
0.6
430 Orifice Inv.
427.00 to
430 to
431 to
03 = 0.0437 Cp * DZ (Z-D/24-Ei)^l'n)
OZ = 0.372 Cp * D*(Z-Ei)^~~~
0~=0
430
431
431.35
Incremental Drawdown Method

Countour Contour
Area Incremental
Volume
Stage, Z
Zone
Q Drawdown
Time
s ft cu ft ft cfs min
430.00 74,547 0 0.00 2 0.000 --
430.10 74,865 7,471 0.10 2 0.085 1,470
430.20 75,184 7,502 0.20 2 0.240 522
430.30 75,502 7,534 0.30 2 0.440 285
430.40 75,821 7,566 0.40 2 0.678 186
430.50 76,139 7,598 0.50 2 0.947 134
430.60 76,457 7,630 0.60 2 1.245 102
430.70 76,776 7,662 0.70 2 1.569 81
430.80 77,094 7,694 0.80 2 1.917 67
430.90 77,413 7,725 0.90 2 2.287 56
431.00 77,731 7,757 1.00 2 2.678 48
431.35 78,845 27,401 1.35 3 3.481 131
Total -- 103,540 -- -- -- 3,083
Drawdown Time =Incremental Volume / O / 60seGmin
Summary
Total Volume = 103,540 cf
Total Time = 3,083 min
Total Time = 2.14 days

C ~ ~ Kimley-Horn
0 and Associates, Inc.
Extended Stormwater Wetland Design Summary
Proposed Extended Detention Wetland #2
Project Information
Project Name: South Park Village
KHA Project #: 011919012
Designed by: JDA Date: 4/2/2007
Checked by: WAC Date: 4 /1 112 0 0 7
Revised by: MCP Date: 5/15/2007
Checked by: Date:
Design Resource: NCDENR -Stormwater Best Management Practices (April 1999)
NCDENR -Updated Draft Manual of Stormwater Best Management Practices (July 2005)
Site Information
Sub Area Location: WETLAND C
Drainage Area (DA) = 4.38 Acres
Impervious Area (IA) = 3.47 Acres
Percent Impervious (I) = 79.4
Required Surface Area
Permanent Pool Depth: 3 ft
SA/DA = 3.33 (85% TSS Removal via Pond)
Min Req'd Surface Area = 6,349 sf (at Permanent Pool)
Required Storage Volume (Water Quality):
Design Storm = 1 inch
Determine Rv Value = 0.05 + .009 (I) = 0.76 in/in
Storage Volume Required = 12,144 cf (above Permanent Pool)
Required Forbay Sizing
Required Volume = 20.00% of Permenant Pool
Permanent Pool Volume = 17,968 cf
Required Forbay Volume = 3,594
Ext. Wetland Surface Area Requirements:
Surface Area % of Approx. Surface
Depth of Perm. Pool Zone ID Permenant Pool Area (sf )
0" - 12" Marsh 70.00% 4,444
0" - 6" Low Marsh 35.00% 2,222
6" - 12" High Marsh 35.00% 2,222
12" - 36" Outlet Pool 15.00% 952
Summary of Proposed Ext. Wetland
Bottom of Pond Elevation = 448.00 ft
Permanent Pool Elevation = 451.00 ft
Temporary Pool Elevation = 452.00 ft
Top of Pond Elevation = 455.00 ft
Permanent Pool Surface Area = 12,567 sf (Elev = 451 )
Temporary Pool (water quality storage) = 13,376 cf (Required Volume = 12143.9835 )
Area @ Top of Temporary Pool = 14,184 sf (Elev = 452 )
Side Slopes of Pond = 3 : 1
Volume of Forebay 4,928 cf (Required volume = 3593.5 )

De th of Perm. Pool
Zone ID Surface Area % of
Permenant Pool Approx. Surface
Area sf
0" - 12" Marsh 70% 8,797
0" - 6" Hi h Marsh 35% 4,398
6" - 12" Low Marsh 35% 4,399
12" - 36" Outlet Pool 15% 1,945
- Foreba 15% 1,885

Anti-Flotation Device
Riser Width = 4 ft
Riser Length = 4 ft
Top Riser Elev. = 453.00
Bottom Riser Elev. = 451.00 ft
Height of Riser = 2.00 ft
Area of Riser = 16.0 sf (Water Displaced)
Volume of Riser = 32.0 d (water Displaced)
Factor of Safety = 1.2
Weight = 1996.8 Ibs
Weight Req'd from Anti-Flotation Device = 2396.2 Ibs
'Weight of Riser = 744.6 Ibs (Volume Riser Wall' Buoyant Wt.)
Additional Volume of Concrete Req'd = 18.9 d (Buoyant Wt Concrete = (150-62.4) pcf)
Extend Riser = 0 ft
Volume of Riser Extension = 0.0 cf
Volume of Anti-flotation 5' x5' Concrete Slab = 25.0
Volume Provided = 25.0
Is the Anti-flotation Device Sufficient (yes/no)? Yes
V
2
%~ • :.
Oft
I 5' x 5' concrete Slab I 1'
25.0 > 18.9
'Assume 6" riser wall thickness with buoyant weight of concrete = (150.62.4) pcf

C ~ /, Kimley-Horn
'~.. and Associates,lnc.
Extended Detention Wetland 2
INCREMENTAL DRAWDOWN METHOD
Project Information
Project Name: South Park Village
KHA Project #: 011919012
Designed by: JDA Date: 4/2/2007
Checked by: WAC Date: 4/11/2007
Revised by: MCP Date: 5/15/2007
Checked by: Date:
Water Quality Orifice
Incremental Determination of Water Quality Volume Drawdown Time
Zone 2
Orifice Diameter (D) _
Cd =
Ei =
Zone 1 Range =
Zone 2 Range =
Zone 3 Range =
Q3 = 0.0437 Cp * DZ (Z-D/24-Ei)^c'iz>
Q2 = 0.372 Cp ~ D'(Z-Ei)^c~z>
Q~=O
2.5 in
0.6
451 Orifice Inv.
448.00 to 451
451 to 451.2083
451.2083333 to 452
Incremental Drawdown Method
Countour Contour
Area Incremental
Volume Stage, Z Zone Q Drawdown
Time
sq ft cu ft ft cfs min
451.00 12,567 0 0.00 2.00 0.000 -
451.10 12,729 1,265 0.10 2.00 0.018 1,195
451.20 12,890 1,281 0.20 2.00 0.050 428
451.30 13,052 1,297 0.30 3.00 0.073 298
451.40 13,214 1,313 0.40 3.00 0.089 246
451.50 13,376 1,329 0.50 3.00 0.103 215
451.60 13,537 1,346 0.60 3.00 0.115 194
451.70 13,699 1,362 0.70 3.00 0.126 179
451.80 13,861 1,378 0.80 3.00 0.137 168
451.90 14,022 1,394 0.90 3.00 0.146 159
452.00 14,184 1,410 1.00 4.00 0.155 152
Total -- 13,376 -- -- -- 3,233
Drawdown Time =Incremental Volume / Q / 60sec/min
Summary
Total Volume = 13,376 cf
Total Time = 3,233 min
Total Time = 2.25 days

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WETLAND 1
Incremental Accumulated
Countour Contour Area Volume Volume, S Stage, Z
sq ft cu ft cu ft ft
427.00 6,876 0 0 0.00
428.00 8,534 7,705 7,705 1.00
429.00 10,400 9,467 17,172 2.00
429.50 46,726 14,282 31,454 2.50
430.00 74,547 30,318 61,772 3.00
431.00 77,731 76,139 137,911 4.00
431.35 78,865 27,404 165,315 4.35
432.00 80,972 79,352 217,262 5.00
433.00 84,270 82,621 299,883 6.00
434.00 87,624 85,947 385,830 7.00
435.00 91,036 89,330 475,160 8.00
FOREBAY-1
Incremental Accumulated
Countour Contour Area Volume Volume, S Stage, Z
sq ft cu ft cu ft ft
428.00 7,455 0 0 1.00
429.00 8,551 8,003 8,003 2.00
429.50 9,123 12,434 12,434 2.50
WETLAND 2
Incremental Accumulated
Countour Contour Area Volume Volume, S Stage, Z
sq ft cu ft cu ft ft
448.00 1812 0 0 0.00
449.00 2719 2,266 2,266 1.00
450.00 8059 5,389 7,655 2.00
451.00 12,567 10,313 17,968 3.00
452.00 14,184 13, 376 31, 343 4.00
453.00 15,859 15,022 46,365 5.00
454.00 17,591 16,725 63,090 6.00
455.00 19,380 18,486 81,575 7.00
FOREBAY-2
Incremental Accumulated
Countour Contour Area Volume Volume, S Stage, Z
sq ft cu ft cu ft ft
449.00 1,396 0 0 .0.00
450.00 1,851 1,624 1,624 1.00
451.00 2,363 2,107 3,731 2.00
Permanent Pool
Temporary Pool
Top of Berm
Permanent Pool
Temporary Pool
Top of Berm

]'+Y. ~'~$..~i ~NF V`AT'.
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WATER QUANTITY

Offsite-AF-Re Offsite-Raar-Re
POI 2 Re-Dev
Across SbRc
Ex Site 48' Re ~-.
n
a A
s ~
i ~ Ex•Ske 18` Re r
~ E F
i ~ a yam
~i P Re 12' RCP
Sao QP 10
~a~~w
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P041-Re
Offsde-AF-Post Off-Rear-Post
Ex Ske Post Across 55-Posl
T ry~
m
T~~s ~ ~ o ~~Qo~
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,~: 1 WetWnd 1
ny
POE1-Post
Onspe
9
~~~
42
O
OffsNe-Existing Welland
,.: / Wegantl2
z
c ,~O
c~
c Pear
POI 2-Post

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Table of Contents
Table of Contents
********************** MASTER SUMMARY **********************
Watershed....... Master Network Summary ............. 1.01
*************** NETWORK SUMMARIES (DETAILED) ***************
Watershed....... 1
Executive Summary (Nodes) .......... 2.01
Watershed....... 2
Executive Summary (Nodes) .......... 2.02
Watershed....... 10
Executive Summary (Nodes) .......... 2.03
Watershed....... 25
Executive Summary (Nodes) .......... 2.09
Watershed....... 50
Executive Summary (Nodes) .......... 2.05
Watershed....... 100
Executive Summary (Nodes) .......... 2.06
****************** DESIGN STORMS SUMMARY *******************
Wake County, NC Design Storms ...................... 3.01
*********************r RAINFALL DATA ***********************
TypeII 24hr.... 1
Synthetic Curve .................... 4.01
********************** TC CALCULATIONS *********************
ACROSS 55-POST.. Tc Calcs ........................... 5.01
i
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Table of Contents
ii
Table of Contents (continued)
ACROSS 55-PRE... Tc Calcs ........................... 5.03
EX SITE 48" PRE Tc Calcs ........................... 5.05
EX SITE POST.... Tc Calcs ........................... 5.09
EX-SITE 18" PRE Tc Calcs ........................... 5.11
OFF-REAR-POST... Tc Calcs ........................... 5.15
OFFSITE-AF-POST Tc Calcs ........................... 5.19
OFFSITE-AF-PRE.. Tc Calcs ........................... 5.23
OFFSITE-EXISTING Tc Calcs ........................... 5.28
OFFSITE-REAR-PRE Tc Calcs ........................... 5.31
ONSITE.......... Tc Calcs ........................... 5.36
POI 2 PRE-DEV... Tc Calcs ........................... 5.38
PRE 12" RCP..... Tc Calcs ........................... 5.41
~~~~~~*~*~***~~~~~~~*~ CN CALCULATIONS *****~**+*~~~*~~*~~~~
ACROSS 55-POST.. Runoff CN-Area ..................... 6.01
ACROSS 55-PRE... Runoff CN-Area ..................... 6.02
EX SITE 48" PRE Runoff CN-Area ..................... 6.03
EX SITE POST.... Runoff CN-Area ..................... 6.09
EX-SITE 18" PRE Runoff CN-Area ..................... 6.05
OFF-REAR-POST... Runoff CN-Area ..................... 6.06
OFFSITE-AF-POST Runoff CN-Area ..................... 6.07
OFFSITE-AF-PRE.. Runoff CN-Area ..................... 6.08
OFFSITE-EXISTING Runoff CN-Area ..................... 6.09
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

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Table of Contents
Table of Contents (continued)
OFFSITE-REAR-PRE Runoff CN-Area ..................... 6.10
ONSITE.......... Runoff CN-Area ..................... 6.11
POI 2 PRE-DEV... Runoff CN-Area ..................... 6.12
PRE 12" RCP..... Runoff CN-Area ..................... 6.13
*********************** POND VOLUMES ***********************
WETLAND 1....... Vol: Elev-Area ..................... 7.01
WETLAND 2....... Vol: Elev-Area ..................... 7.02
******************** OUTLET STRUCTURES *********************
Wetland 1 Outlet Outlet Input Data .................. 8.01
Wetland 2 Outlet Outlet Input Data .................. 8.05
iii
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Master Network Summary Page 1.01
Name.... Watershed
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
MASTER DESIGN STORM SUMMARY
Network Storm Collection: Wake County, NC
Total
Depth Rainfall
Return Event in Type RNF
-------- ID
--------
------------
1 ------
3.0000 ----------
Synthetic ------
Curve TypeII 24hr
2 3.6000 Synthetic Curve TypeII 24hr
10 5.3800 Synthetic Curve TypeII 24hr
25 6.4000 Synthetic Curve TypeII 24hr
50 7.2100 Synthetic Curve TypeII 24hr
100 8.0000 Synthetic Curve TypeII 24hr
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft Trun min cfs ft ac-ft
-------- -------- ------------
--------
ACROSS ---------
55-POST ----
AREA ------
1 ---------- --
.453 ---------
716.00 8.51
ACROSS 55-POST AREA 2 .613 715.00 11.52
ACROSS 55-POST AREA 10 1.124 715.00 21.00
ACROSS 55-POST AREA 25 1.431 715.00 26.54
ACROSS 55-POST AREA 50 1.680 715.00 30.96
ACROSS 55-POST AREA 100 1.925 715.00 35.26
ACROSS 55-PRE AREA 1 .220 716.00 3.66
ACROSS 55-PRE AREA 2 .333 716.00 5.92
ACROSS 55-PRE AREA 10 .735 716.00 13.75
ACROSS 55-PRE AREA 25 .995 716.00 18.70
ACROSS 55-PRE AREA 50 1.211 716.00 22.77
ACROSS 55-PRE AREA 100 1.429 715.00 26.87
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

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Type.... Master Network Summary Page 1.02
Name.... Watershed
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft Trun min cfs ft ac-ft
EX SITE 48" PRE AREA 1 .824 727.00 8.15
EX SITE 48" PRE AREA 2 1.311 727.00 14.71
EX SITE 48" PRE AREA 10 3.112 726.00 38.84
EX SITE 48" PRE AREA 25 4.309 725.00 54.86
EX SITE 48" PRE AREA 50 5.318 725.00 68.29
EX SITE 48" PRE AREA 100 6.341 725.00 81.81
EX SITE POST AREA 1 5.206 715.00 96.35
EX SITE POST AREA 2 6.625 715.00 121.36
EX SITE POST AREA 10 10.937 715.00 195.08
EX SITE POST AREA 25 13.445 715.00 236.92
EX SITE POST AREA 50 15.496 715.00 269.96
EX SITE POST AREA 100 17.404 715.00 302.05
EX-SITE 18" PRE AREA 1 .088 728.00 .72
EX-SITE 18" PRE AREA 2 .152 726.00 1.60
EX-SITE 18" PRE AREA 10 .405 725.00 5.24
EX-SITE 18" PRE AREA 25 .579 724.00 7.76
EX-SITE 18" PRE AREA 50 .729 724.00 9.92
EX-SITE 18" PRE AREA 100 .883 724.00 12.11
OFF-REAR-POST AREA 1 .445 740.00 2.79
OFF-REAR-POST AREA 2 .699 740.00 9.97
OFF-REAR-POST AREA 10 1.628 740.00 13.07
OFF-REAR-POST AREA 25 2.241 790.00 18.36
OFF-REAR-POST AREA 50 2.755 735.00 22.78
OFF-REAR-POST AREA 100 3.277 735.00 27.32
OFFSITE-AF-POST AREA 1 .673 727.00 7.79
OFFSITE-AF-POST AREA 2 .961 727.00 11.40
OFFSITE-AF-POST AREA 10 1.933 727.00 23.49
OFFSITE-AF-POST AREA 25 2.539 726.00 30.92
OFFSITE-AF-POST AREA 50 3.035 726.00 36.94
OFFSITE-AF-POST AREA 100 3.530 726.00 42.88
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00) 3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Master Network. Summary Page 1.03
Name.... Watershed
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type
----------------- ---- Event
------ ac-ft Trun
---------- -- min
--------- cfs ft ac-ft
-------- ------

OFFSITE-AF-PRE AREA
1
.673
729.00 -- ------------
6.80
OFFSITE-AF-PRE AREA 2 .961 729.00 10.08
OFFSITE-AF-PRE AREA 10 1.933 729.00 20.97
OFFSITE-AF-PRE AREA 25 2.539 729.00 27.64
OFFSITE-AF-PRE AREA 50 3.036 729.00 33.05
OFFSITE-AF-PRE AREA 100 3.530 729.00 38.39
OFFSITE-EXISTING AREA 1 .092 725.00 .68
OFFSITE-EXISTING AREA 2 .169 724.00 1.85
OFFSITE-EXISTING AREA 10 .490 722.00 7.09
OFFSITE-EXISTING AREA 25 .718 722.00 10.83
OFFSITE-EXISTING AREA 50 .916 721.00 14.04
OFFSITE-EXISTING AREA 100 1.121 721.00 17.37
OFFSITE-REAR-PRE AREA 1 .428 746.00 2.46
OFFSITE-REAR-PRE AREA 2 .671 746.00 4.32
OFFSITE-REAR-PRE AREA 10 1.563 741.00 11.44
OFFSITE-REAR-PRE AREA 25 2.151 741.00 16.16
OFFSITE-REAR-PRE AREA 50 2.645 740.00 20.10
OFFSITE-REAR-PRE AREA 100 3.145 740.00 24.08
ONSITE AREA 1 .724 715.00 13.47
ONSITE AREA 2 .927 715.00 17.10
ONSITE AREA 10 1.598 715.00 27.83
ONSITE AREA 25 1.910 715.00 33.93
ONSITE AREA 50 2.199 715.00 38.75
ONSITE AREA 100 2.482 715.00 43.42
POI 2 PRE-DEV AREA 1 .295 727.00 2.21
POI 2 PRE-DEV AREA 2 .519 727.00 5.22
POI 2 PRE-DEV AREA 10 1.917 725.00 18.21
POI 2 PRE-DEV AREA 25 2.043 724.00 27.27
POI 2 PRE-DEV AREA 50 2.582 724.00 35.07
POI 2 PRE-DEV AREA 100 3.136 724.00 93.09
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

•
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~~
~~
•
Type.... Master Network Summary Page 1.04
Name.... Watershed
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft Trun min cfs ft ac-ft
*POI 2-POST JCT 1 .747 R 726.00 1.23
*POI 2-POST JCT 2 1.014 R 725.00 3.01
*POI 2-POST JCT 10 1.923 R 724.00 13.60
*POI 2-POST JCT 25 2.498 R 722.00 19.81
*POI 2-POST JCT 50 2.973 R 724.00 26.03
*POI 2-POST JCT 100 3.452 R 723.00 38.40
*POI-I-POST JCT 1 6.289 R 749.00 19.74
*POI-I-POST JCT 2 8.348 R 736.00 29.64
*POI-I-POST JCT 10 14.934 R 731.00 63.25
*POI-I-POST JCT 25 18.921 R 726.00 115.22
*POI-I-POST JCT 50 22.154 R 724.00 167.19
*POI-I-POST JCT 100 25.350 R 724.00 216.44
*POI-I-PRE JCT 1 2.603 729.00 21.65
*POI-I-PRE JCT 2 3.991 727.00 36.20
*POI-I-PRE JCT 10 8.987 726.00 89.89
*POI-I-PRE JCT 25 12.249 726.00 124.82
*POI-I-PRE JCT 50 14.980 725.00 153.97
*POI-I-PRE JCT 100 17.736 725.00 183.28
*POI-2-PRE JCT 1 .295 727.00 2.21
*POI-2-PRE JCT 2 .519 727.00 5.22
*POI-2-PRE JCT 10 1.417 725.00 18.21
*POI-2-PRE JCT 25 2.043 724.00 27.27
*POI-2-PRE JCT 50 2.582 724.00 35.07
*POI-2-PRE JCT 100 3.136 724.00 43.04
PRE 12" RCP AREA 1 .371 728.00 3.85
PRE 12" RCP AREA 2 .562 728.00 6.29
PRE 12" RCP AREA 10 1.239 726.00 14.85
PRE 12" RCP AREA 25 1.677 726.00 20.36
PRE 12" RCP AREA 50 2.041 726.00 24.91
PRE 12" RCP AREA 100 2.408 726.00 29.45
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

i
•
i
•
Type.... Master Network Summary Page 1.05
Name.... Watershed
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)
Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft
-------- Trun
-- min
--------- cfs
-------- ft
-------- ac-ft
------------
---------
WETLAND ---
1 -----
IN ----
POND ------
1 --
6.777 715.00 108.30
WETLAND 1 IN POND 2 8.899 715.00 138.84
WETLAND 1 IN POND 10 15.622 715.00 231.67
WETLAND 1 IN POND 25 19.655 715.00 285.39
WETLAND 1 IN POND 50 22.916 715.00 328.14
WETLAND 1 IN POND 100 26.135 715.00 369.87
WETLAND 1 OUT POND 1 6.289 R 749.00 14.74 431.87 3.330
WETLAND 1 OUT POND 2 8.348 R 736.00 29.64 432.25 4.039
WETLAND 1 OUT POND 10 14.934 R 731.00 63.25 433.49 6.415
WETLAND 1 OUT POND 25 18.921 R 726.00 115.22 439.06 7.564
WETLAND 1 OUT POND 50 22.154 R 724.00 167.19 434.41 8.266
WETLAND 1 OUT POND 100 25.350 R 724.00 216.44 434.68 8.832
WETLAND 2 IN POND 1 .724 715.00 13.47
WETLAND 2 IN POND 2 .927 715.00 17.10
WETLAND 2 IN POND 10 1.548 715.00 27.83
WETLAND 2 IN POND 25 1.910 715.00 33.93
WETLAND 2 IN POND 50 2.199 715.00 38.75
WETLAND 2 IN POND 100 2.482 715.00 43.42
WETLAND 2 OUT POND 1 .655 R 769.00 .80 452.33 .416
WETLAND 2 OUT POND 2 .845 R 748.00 1.49 452.61 .511
WETLAND 2 OUT POND 10 1.433 R 726.00 6.89 453.35 .782
WETLAND 2 OUT POND 25 1.779 R 725.00 9.14 453.75 .936
WETLAND 2 OUT POND 50 2.057 R 725.00 12.86 454.07 1.063
WETLAND 2 OUT POND 100 2.331 R 723.00 21.34 454.25 1.136
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Executive Summary (Nodes) Page 2.01
Name.... Watershed Event: 1 yr
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Storm... TypeII 24hr Tag: 1
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm File,ID = Wake County, NC
Storm Tag Name = 1
Data Type, File, ID =
Storm Frequency =
Total Rainfall Depth=
Duration Multiplier =
Resulting Duration =
Resulting Start Time=
Node ID
-----------------
ACROSS 55-POST
ACROSS 55-PRE
EX SITE 48" PRE
EX SITE POST
EX-SITE 18" PRE
OFF-REAR-POST
OFFSITE-AF-POST
OFFSITE-AF-PRE
OFFSITE-EXISTING
OFFSITE-REAR-PRE
ONSITE
POI 2 PRE-DEV
Outfall POI 2-POST
Outfall POI-I-POST
Outfall POI-I-PRE
Outfall POI-2-PRE
PRE 12" RCP
WETLAND 1 IN
WETLAND 1 OUT
WETLAND 2 IN
WETLAND 2 OUT
Synthetic Storm TypeII 24hr
1 yr
3.0000 in
1
1440.00 min
.00 min Step= 6.00 min End= 1440.00 min
HYG Vol Qpeak Qpeak Max WSEL
Type
---- ac-ft
--------- Trun.
- -- - min
-------- cfs
-------- ft
---------
AREA .453 716.00 8.51
AREA .220 716.00 3.66
AREA .824 727.00 8.15
AREA 5.206 715.00 96.35
AREA .088 728.00 .72
AREA .445 740.00 2.79
AREA .673 727.00 7.74
AREA .673 729.00 6.80
AREA .092 725.00 .68
AREA .428 796.00 2.46
AREA .724 715.00 13.47
AREA .295 727.00 2.21
JCT .747 R 726.00 1.23
JCT 6.289 R 749.00 14.74
JCT 2.603 729.00 21.65
JCT .295 727.00 2.21
AREA .371 728.00 3.85
POND 6.777 715.00 108.30
POND 6.289 R 749.00 14.74 431.87
POND .724 715.00 13.47
POND .655 R 769.00 .80 452.33
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Executive Summary (Nodes) Page 2.02
Name.... Watershed Event: 2 yr
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Storm... TypeII 24hr Tag: 2
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm File,ID = Wake County, NC
Storm Tag Name = 2
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 2 yr
Total Rainfall Depth= 3.6000 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min
Node ID
-----------------
ACROSS 55-POST
ACROSS 55-PRE
EX SITE 48" PRE
EX SITE POST
EX-SITE 18" PRE
OFF-REAR-POST
OFFSITE-AF-POST
OFFSITE-AF-PRE
OFFSITE-EXISTING
OFFSITE-REAR-PRE
ONSITE
POI 2 PRE-DEV
Outfall POI 2-POST
Outfall POI-I-POST
Outfall POI-I-PRE
Outfall POI-2-PRE
PRE 12" RCP
WETLAND 1 IN
WETLAND 1 OUT
WETLAND 2 IN
WETLAND 2 OUT
HYG Vol Qpeak Qpeak Max WSEL
Type ac-ft Trun. min
- cfs
-------- ft
---------
----
AREA ----------
.613 -- - -------
715.00 11.52
AREA .333 716.00 5.92
AREA 1.311 727.00 14.71
AREA 6.625 715.00 121.36
AREA .152 726.00 1.60
AREA .699 740.00 4.97
AREA .961 727.00 11.40
AREA .961 729.00 10.08
AREA .169 724.00 1.85
AREA .671 746.00 4.32
AREA .927 715.00 17.10
AREA .519 727.00 5.22
JCT 1.014 R 725.00 3.01
JCT 8.348 R 736.00 29.64
JCT 3.991 727.00 36.20
JCT .519 727.00 5.22
AREA .562 728.00 6.29
POND 8.899 715.00 138.84
POND 8.348 R 736.00 29.64 432.25
POND .927 715.00 17.10
POND .845 R 748.00 1.49 452.61
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

•
•
Type.... Executive Summary (Nodes) Page 2.03
Name.... Watershed Event: 10 yr
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Storm... TypeII 24hr Tag: 10
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm File,ID = Wake County, NC
Storm Tag Name = 10
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 10 yr
Total Rainfall Depth= 5.3800 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1990.00 min
Node ID
----------------
- ACROSS 55-POST
ACROSS 55-PRE
EX SITE 48" PRE
EX SITE POST
EX-SITE 18" PRE
OFF-REAR-POST
OFFSITE-AF-POST
OFFSITE-AF-PRE
OFFSITE-EXISTING
OFFSITE-REAR-PRE
ONSITE
POI 2 PRE-DEV
Outfall POI 2-POST
Outfall POI-I-POST
Outfall POI-I-PRE
Outfall POI-2-PRE
PRE 12" RCP
WETLAND 1 IN
WETLAND 1 OUT
WETLAND 2 IN
WETLAND 2 OUT
HYG Vol Qpeak
Type
---- ac-ft
--------- Trun.
- -- - min
--------
AREA 1.124 715.00
AREA .735 716.00
AREA 3.112 726.00
AREA 10.937 715.00
AREA .405 725.00
AREA 1.628 740.00
AREA 1.933 727.00
AREA 1.933 729.00
AREA .490 722.00
AREA 1.563 741.00
AREA 1.548 715.00
AREA 1.417 725.00
JCT 1.923 R 724.00
JCT 14.934 R 731.00
JCT 8.987 726.00
JCT 1.417 725.00
AREA 1.239 726.00
POND 15.622 715.00
POND 14.934 R 731.00
POND 1.548 715.00
POND 1.433 R 726.00
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Qpeak Max WSEL
cfs ft
21.00
13.75
38.84
195.08
5.24
13.07
23.49
20.97
7.09
11.44
27.83
18.21
13.60
63.25
89.89
18.21
14.85
231.67
63.25 433.49
27.83
6.89 453.35
Bentley Systems, Inc.
5/31/2007

i
•
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~~
Type.... Executive Summary (Nodes) Page 2.04
Name.... Watershed Event: 25 yr
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Storm... TypeII 24hr Tag: 25
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm File,ID = Wake County, NC
Storm Tag Name = 25
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 25 yr
Total Rainfall Depth= 6.4000 in
Duration Multiplier = 1
Resulting Duration = 1490.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1940.00 min

- Node ID
----------------
ACROSS 55-POST
ACROSS 55-PRE
EX SITE 48" PRE
EX SITE POST
EX-SITE 18" PRE
OFF-REAR-POST
OFFSITE-AF-POST
OFFSITE-AF-PRE
OFFSITE-EXISTING
OFFSITE-REAR-PRE
ONSITE
POI 2 PRE-DEV
Outfall POI 2-POST
Outfall POI-I-POST
Outfall POI-I-PRE
Outfall POI-2-PRE
PRE 12" RCP
WETLAND 1 IN
WETLAND 1 OUT
WETLAND 2 IN
WETLAND 2 OUT
HYG Vol Qpeak Qpeak Max WSEL
Type ac-ft Trun.
- min
-------- cfs
-------- ft
---------
----
AREA ----------
1.431 -- 715.00 26.54
AREA .995 716.00 18.70
AREA 4.309 725.00 54.86
AREA 13.445 715.00 236.92
AREA .579 724.00 7.76
AREA 2.241 740.00 18.36
AREA 2.539 726.00 30.92
AREA 2.539 729.00 27.64
AREA .718 722.00 10.83
AREA 2.151 741.00 16.16
AREA 1.910 715.00 33.93
AREA 2.043 724.00 27.27
JCT 2.498 R 722.00 19.81
JCT 18.921 R 726.00 115.22
JCT 12.249 726.00 124.82
JCT 2.093 724.00 27.27
AREA 1.677 726.00 20.36
POND 19.655 715.00 285.39
POND 18.921 R 726.00 115.22 934.06
POND 1.910 715.00 33.93
POND 1.779 R 725.00 9.14 453.75
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Executive Summary (Nodes) Page 2.05
Name.... Watershed Event: 50 yr
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Storm... TypeIl 24hr Tag: 50
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm File,ID = Wake County, NC
Storm Tag Name = 50
Data Type, File, ID = Synthetic Storm TypeII 29hr
Storm Frequency = 50 yr
Total Rainfall Depth= 7.2100 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min

- Node ID
----------------
ACROSS 55-POST
ACROSS 55-PRE
EX SITE 48" PRE
EX SITE POST
EX-SITE 18" PRE
OFF-REAR-POST
OFFSITE-AF-POST
OFFSITE-AF-PRE
OFFSITE-EXISTING
OFFSITE-REAR-PRE
ONSITE
POI 2 PRE-DEV
Outfall POI 2-POST
Outfall POI-I-POST
Outfall POI-I-PRE
Outfall POI-2-PRE
PRE 12" RCP
WETLAND 1 IN
WETLAND 1 OUT
WETLAND 2 IN
WETLAND 2 OUT
HYG Vol Qpeak Qpeak Max WSEL
Type ac-ft Trun. min
----- cfs
-------- ft
---------
----
AREA ----------
1.680 -- - ---
715.00 30.96
AREA 1.211 716.00 22.77
AREA 5.318 725.00 68.29
AREA 15.946 715.00 269.96
AREA .729 724.00 9.92
AREA 2.755 735.00 22.78
AREA 3.035 726.00 36.94
AREA 3.036 729.00 33.05
AREA .916 721.00 14.04
AREA 2.645 740.00 20.10
AREA 2.199 715.00 38.75
AREA 2.582 724.00 35.07
JCT 2.973 R 724.00 26.03
JCT 22.154 R 724.00 167.19
JCT 14.980 725.00 153.97
JCT 2.582 724.00 35.07
AREA 2.041 726.00 24.91
POND 22.916 715.00 328.14
POND 22.154 R 724.00 167.19 434.41
POND 2.199 715.00 38.75
POND 2.057 R 725.00 12.86 454.07
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

~'
~'
~~
~~
~~
~~
.~
i-
~~
~~
.~
.~
~~
~~
.~
~~
~~
.~
.~
~~
~~
~~
.~
.!
it
.~
.~
.'
.~
.I
.'
.'
11
~I
Type.... Executive Summary (Nodes) Page 2.06
Name.... Watershed Event: 100 yr
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Storm... TypeII 24hr Tag: 100
NETWORK SUMMARY -- NODES
(Trun.= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left & Rt)
DEFAULT Design Storm File,ID = Wake County, NC
Storm Tag Name = 100
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 100 yr
Total Rainfall Depth= 8.0000 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min
Node ID
--------------
- --
ACROSS 55-POST
ACROSS 55-PRE
EX SITE 48" PRE
EX SITE POST
EX-SITE 18" PRE
OFF-REAR-POST
OFFSITE-AF-POST
OFFSITE-AF-PRE
OFFSITE-EXISTING
OFFSITE-REAR-PRE
ONSITE
POI 2 PRE-DEV
Outfall POI 2-POST
Outfall POI-I-POST
Outfall POI-I-PRE
Outfall POI-2-PRE
PRE 12" RCP
WETLAND 1 IN
WETLAND 1 OUT
WETLAND 2 IN
WETLAND 2 OUT
HYG Vol Qpeak Qpeak Max W5EL
Type ac-ft Trun. min
------- cfs
-------- ft
---------
----
AREA ----------
1.925 -- - -
715.00 35.26
AREA 1.429 715.00 26.87
AREA 6.341 725.00 81.81
AREA 17.404 715.00 302.05
AREA .883 724.00 12.11
AREA 3.277 735.00 27.32
AREA 3.530 726.00 42.88
AREA 3.530 729.00 38.39
AREA 1.121 721.00 17.37
AREA 3.145 790.00 24.08
AREA 2.482 715.00 43.42
AREA 3.136 724.00 43.04
JCT 3.452 R 723.00 38.40
JCT 25.350 R 724.00 216.44
JCT 17.736 725.00 183.28
JCT 3.136 724.00 43.04
AREA 2.408 726.00 29.45
POND 26.135 715.00 369.87
POND 25.350 R 724.00 216.44 434.68
POND 2.482 715.00 43.42
POND 2.331 R 723.00 21.34 454.25
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

• Type.... Design Storms
_ Name.... Wake County, NC
Page 3.01
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Title... Project Date: 1/23/2007
Project Engineer: David Arnold
Project Title: SouthPark Village
Project Comments:
DESIGN STORMS SUMMARY
Design Storm File,ID = Wake County, NC
Storm Tag Name = 1
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 1 yr
Total Rainfall Depth= 3.0000 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min
Storm Tag Name = 2
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency 2 yr
Total Rainfall Depth= 3.6000 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min
Storm Tag Name = 10
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 10 yr
Total Rainfall Depth= 5.3800 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min
Storm Tag Name = 25
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 25 yr
Total Rainfall Depth= 6.4000 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min
Storm Tag Name = 50
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 50 yr
Total Rainfall Depth= 7.2100 in
Duration Multiplier = 1
Resulting Duration = 1440.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Design Storms
Name.... Wake County, NC
Page 3.02
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Title... Project Date: 1/23/2007
Project Engineer: David Arnold
Project Title: SouthPark Village
Project Comments:
DESIGN STORMS SUMMARY
Design Storm File,ID =
Storm Tag Name = 100
Wake County, NC
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 100 yr
Total Rainfall Depth= 8.0000 in
Duration Multiplier = 1
Resulting Duration = 1940.00 min
Resulting Start Time= .00 min Step= 6.00 min End= 1440.00 min
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Synthetic Curve
Name.... TypeII 24hr Tag: 1
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Page 4.01
CUMULATIVE RAINFALL FRACTIONS
Time I Output Time increment = 6.00 min
min I Time on left represents time for first value in each row.
-
---------I-
.00 I ----------------
.000 ---------------
.001 ----------
.002 ---------
.003 ----
------
.004
30.00 I .005 .006 .007 .008 .009
60.00 I .011 .012 .013 .014 .015
90.00 I .016 .017 .018 .020 .021
120.00 I .022 .023 .024 .026 .027
150.00 I .028 .029 .031 .032 .033
180.00 I .035 .036 .037 .038 .040
210.00 I .041 .042 .044 .045 .047
240.00 I .048 .049 .051 .052 .054
270.00 I .055 .057 .058 .060 .061
300.00 I .063 .065 .066 .068 .070
330.00 I .071 .073 .075 .076 .078
360.00 I .080 .082 .084 .085 .087
390.00 I .089 .091 .093 .095 .097
420.00 I .099 .101 .103 .105 .107
450.00 I .109 .111 .113 .116 .118
480.00 I .120 .122 .125 .127 .130
510.00 I .132 .135 .138 .141 .144
540.00 I .147 .150 .153 .157 .160
570.00 I .163 .166 .170 .173 .177
600.00 ( .181 .185 .189 .194 .199
630.00 I .204 .209 .215 .221 .228
660.00 I .235 .243 .251 .261 .271
690.00 I .283 .307 .354 .431 .568
720.00 I .663 .682 .699 .713 .725
750.00 I .735 .743 .751 .759 .766
780.00 I .772 .778 .784 .789 .794
810.00 I .799 .804 .808 .812 .816
840.00 I .820 .824 .827 .831 .834
870.00 I .838 .841 .844 .847 .850
900.00 I .854 .856 .859 .862 .865
930.00 I .868 .870 .873 .875 .878
960.00 I .880 .882 .885 .887 .889
990.00 I .891 .893 .895 .898 .900
1020.00 I .902 .904 .906 .908 .910
1050.00 I .912 .914 .915 .917 .919
1080.00 I .921 .923 .925 .926 .928
1110.00 I .930 .931 .933 .935 .936
1140.00 I .938 .939 .941 .942 .944
1170.00 I .995 .947 .948 .949 .951
1200.00 I .952 .953 .955 .956 .957
1230.00 I .958 .960 .961 .962 .964
1260.00 I .965 .966 .967 .968 .970
1290.00 I .971 .972 .973 .975 .976
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Synthetic Curve Page 4.02
Name.... TypeII 24hr Tag: 1
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
CUMULATIVE RAINFALL FRACTIONS
Time I Output Time increment = 6.00 min
min ~
---------
- Time on left
---------------- represents time
-- for first value in each row.
I
1320.00 I
.977 -------------
.978 -----------
.979 ------
.981 -------------
.982
1350.00 I .983 .984 .985 .986 .988
1380.00 I .989 .990 .991 .992 .993
1410.00 I .994 .996 .997 .998 .999
1440.00 I 1.000
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Tc Calcs
Name.... ACROSS 55-POST
Page 5.01
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: User Defined
Segment #1 Time: 5.00 min
------------------------------------------------------------------------
Total Tc: 5.00 min
-------------------------
-------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
i
•
•
~~
•
i
•
•
•
•
•
•
•
•
Type.... Tc Calcs
Name.... ACROSS 55-POST
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= User Defined
Tc = Value entered by user
Page 5.02
Where: Tc = Time of concentration
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

~~
1~
~~
~~
I~
I~
i~
Type.... Tc Calcs
Name.... ACROSS 55-PRE
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
TIME OF CONCENTRATION CALCULATOR
Segment #1: Tc: User Defined
Segment #1 Time: 5.00 min
------------------------------------------------------------------------
Page 5.03
Total Tc: 5.00 min
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

1~
/,
/,
1~
~r
i~
a~
~~
i
r
i
•
•
•
Type.... Tc Calcs
Name.... ACROSS 55-PRE
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
User Defined ______________________________________________________
Tc = Value entered by user
Page 5.04
Where: Tc = Time of concentration
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

~~
~~
•
w
•
•
•
•
•
•
Type.... Tc Calcs
Name.... EX SITE 48" PRE
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: TR-55 Sheet
Mannings n .2900
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .020000 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: 13.45 min
------------------------------------------------------------------------
Segment #2: Tc: TR-55 Shallow
Hydraulic Length 277.00 ft
Slope .036100 ft/ft
Unpaved
Avg.Velocity 3.07 ft/sec
Segment #2 Time: 1.51 min
------------------------------------------------------------------------
Segment #3: Tc: TR-55 Channel
Flow Area 32.0000 sq.ft
Wetted Perimeter 22.65 ft
Hydraulic Radius 1.41 ft
Slope .008200 ft/ft
Mannings n .0450
Hydraulic Length 813.00 ft
Avg.Velocity 3.78 ft/sec
Segment #3 Time: 3.59 min
------------------------------------------------------------------------
Page 5.05
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... EX SITE 48" PRE
Page 5.06
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Segment #4: Tc: TR-55 Channel
Flow Area 12.5600 sq.ft
Wetted Perimeter 12.56 ft
Hydraulic Radius 1.00 ft
Slope .017400 ft/ft
Mannings n .0130
Hydraulic Length 710.00 ft
Avg.Velocity 15.12 ft/sec
Segment #4 Time: .78 min
------------------------------------------------------------------------
-------------------------
-------------------------
Total Tc: 19.33 min
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... EX SITE 48" PRE
Page 5.07
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
SCS TR-55 Sheet Flow ______________________________________________
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, °s
___= SCS TR-55 Shallow Concentrated Flow _______________________________
Unpaved surface:
V = 16.1395 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... EX SITE 48" PRE
Page 5.08
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
___= SCS Channel Flow __________________________________________________
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)
Where: R
Aq
Wp
V
Sf
n
Tc
Lf
Hydraulic radius
Flow area, sq.ft.
Wetted perimeter, ft
Velocity, ft/sec
Slope, ft/ft
Mannings n
Time of concentration, hrs
Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... EX SITE POST
Page 5.09
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
..................................................................:.....
........................................................................
Segment #1: Tc: User Defined
Segment #1 Time: 5.00 min
------------------------------------------------------------------------
-------------------------
-------------------------
Total Tc: 5.00 min
-------------------------
-------------------------
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

~~
1~
~~
1~
~~
1~
~~
~~
~~
~~
~~
~.
~.
,.
~.
~.
I.
I.
•
Type.... Tc Calcs Page 5.10
Name.... EX SITE POST
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= User Defined ______________________________________________________
Tc = Value entered by user
Where: Tc = Time of concentration
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
•
i
•
•
•
Type.... Tc Calcs
Name.... EX-SITE 18" PRE
Page 5.11
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .020000 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: 13.45 min
------------------------------------------------------------------------
Segment #2: Tc: TR-55 Shallow
Hydraulic Length 259.00 ft
Slope .030800 ft/ft
Unpaved
Avg.Velocity 2.83 ft/sec
Segment #2 Time: 1.52 min
------------------------------------------------------------------------
Segment #3: Tc: TR-55 Shallow
Hydraulic Length
Slope
Unpaved
Avg.Velocity
106.00 ft
099300 ft/ft
4.95 ft/sec
Segment #3 Time: .36 min
------------------------------------------------------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

~~
Type.... Tc Calcs Page 5.12

~~
~
s Name.... EX-SITE 18" PRE

File.... K:\LDEV\011919012 southpark

village cds\Stormwater\DWQ

REPORT AND CALCS 0507\PRE

Segment #4: Tc: TR-55 Channel

Flow Area 1.7700 sq.ft
'~ Wetted Perimeter 4.71 ft
A Hydraulic Radius .38 ft
Slope .016500 ft/ft
~ Mannings n .0130
Hydraulic Length 203.00 ft
r-
Avg.Velocity 7.67 ft/sec
_
~
----------------
------------------- Segment
------------- #4 Time:
-------------- .44 min
----------
•
Segment #5: Tc: TR-55 Channel
•
Flow Area 32.0000 sq.ft
- Wetted Perimeter 22.65 ft
~ Hydraulic Radius 1.41 ft
Slope .023000 ft/ft
• Mannings n .0450
Hydraulic Length 328.00 ft
•
Avg.Velocity 6.32 ft/sec
•
S
----------------
------------------- Segment
------------- #5 Time:
-------------- .86 min
----------
•
• Total Tc: 16.64 min

• _ ______________ __________

•
•

i

•
S/N: DAYXYWJJ6M8 3 Bentley Systems, Inc.

Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

- S/N: UHYXYWJJb11tSJ ~cu~icy .~yo~ciuo, .iai~..
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

•
•
i
•
i
•
•
•
•
•
•
•
•
Type.... Tc Calcs
Name.... OFF-REAR-POST
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Segment #4: Tc: TR-55 Channel
Flow Area 7.0000 sq.ft
wetted Perimeter 10.32 ft
Hydraulic Radius .68 ft
Slope .005700 ft/ft
Mannings n .0450
Hydraulic Length 350.00 ft
Avg.Velocity 1.93 ft/sec
Segment #4 Time: 3.02 min
------------------------------------------------------------------------
Segment #5: Tc: TR-55 Channel
Flow Area 12.5600 sq.ft
Wetted Perimeter 12.56 ft
Hydraulic Radius 1.00 ft
Slope .005000 ft/ft
Mannings n .0130
Hydraulic Length 2278.00 ft
Avg.Velocity 8.10 ft/sec
Segment #5 Time: 4.68 min
------------------------------------------------------------------------
Page 5.16
Total Tc: 39.93 min
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
i
i
i
•
•
•
•
•
•
•
•
•
•
•
Type.... Tc Calcs Page 5.17
Name.... OFF-REAR-POST
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= SCS TR-55 Sheet Flow ______________________________________________
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, ~
___= SCS TR-55 Shallow Concentrated Flow _______________________________
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
•
i
•
•
•
•
Type.... Tc Calcs
Name.... OFF-REAR-POST
Page 5.18
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
___= SCS Channel Flow ___________________
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)
Where: R
Aq
Wp
V
Sf
n
Tc
Lf
Hydraulic radius
Flow area, sq.ft.
Wetted perimeter, ft
Velocity, ft/sec
Slope, ft/ft
Mannings n
Time of concentration, hrs
Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... OFFSITE-AF-POST
Page 5.19
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
...........................................................
TIME OF CONCENTRATION CALCULATOR
Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .020000 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: 13.45 min
------------------------------------------------------------------------
Segment #2: Tc: TR-55 Shallow
Hydraulic Length 728.00 ft
Slope .032000 ft/ft
Unpaved
Avg.Velocity 2.89 ft/sec
Segment #2 Time: 4.20 min
------------------------------------------------------------------------
Segment #3: Tc: TR-55 Channel
Flow Area 4.9100 sq.ft
Wetted Perimeter 7.85 ft
Hydraulic Radius .63 ft
Slope .035000 ft/ft
Mannings n .0130
Hydraulic Length 70.00 ft
Avg.Velocity 15.68 ft/sec
Segment #3 Time: .07 min
------------------------------------------------------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

w
w
Type.... Tc Calcs
Name.... OFFSITE-AF-POST
Page 5.20
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Segment #4: Tc: TR-55 Channel
Flow Area
Wetted Perimeter
Hydraulic Radius
Slope
Mannings n
Hydraulic Length
Avg.Velocity
12.5600 sq.ft
12.56 ft
1.00 ft
.005000 ft/ft
.0130
2018.00 ft
8.10 ft/sec
Segment #4 Time: 9.15 min
------------------------------------------------------------------------
Total Tc: 21.88 min
-------------------------
-------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

i
•
i
i
Type.... Tc Calcs
Name.... OFFSITE-AF-POST
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= SCS TR-55 Sheet Flow ______________________________________________
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope,
___= SCS TR-55 Shallow Concentrated Flow _______________________________
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Page 5.21
Tc = (Lf / V) / (3600sec/hr)
Where: V =Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
Type.... Tc Calcs
Name.... OFFSITE-AF-POST
Page 5.22
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
___= SCS Channel Flow __________________________________________________
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)
Where: R
Aq
Wp
V
Sf
n
Tc
Lf
Hydraulic radius
Flow area, sq.ft.
wetted perimeter, ft
Velocity, ft/sec
Slope, ft/ft
Mannings n
Time of concentration, hrs
Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... OFFSITE-AF-PRE
Page 5.23
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .020000 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: 13.45 min
------------------------------------------------------------------------
Segment #2: Tc: TR-55 Shallow
Hydraulic Length 728.00 ft
Slope .032000 ft/ft
Unpaved
Avg.Velocity 2.89 ft/sec
Segment #2 Time: 4.20 min
------------------------------------------------------------------------
Segment #3: Tc: TR-55 Channel
Flow Area 9.9100 sq.ft
Wetted Perimeter 7.85 ft
Hydraulic Radius .63 ft
Slope .035000 ft/ft
Mannings n .0130
Hydraulic Length 70.00 ft
Avg.Velocity 15.68 ft/sec
Segment #3 Time: .07 min
------------------------------------------------------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
•
•
Type.... Tc Calcs
Name.... OFFSITE-AF-PRE
Page 5.24
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Segment #9: Tc: TR-55 Channel
Flow Area 8.0000 sq.ft
Wetted Perimeter 8.97 ft
Hydraulic Radius .94 ft
Slope .013800 ft/ft
Mannings n .0450
Hydraulic Length 312.00 ft
Avg.Velocity 3.74 ft/sec
Segment #4 Time: 1.39 min
------------------------------------------------------------------------
Segment #5: Tc: TR-55 Channel
Flow Area 88.0000 sq.ft
Wetted Perimeter 35.30 ft
Hydraulic Radius 2.49 ft
Slope .010000 ft/ft
Mannings n .0300
Hydraulic Length 148.00 ft
Avg.Velocity 9.13 ft/sec
Segment #5 Time: .27 min
------------------------------------------------------------------------
Segment #6: Tc: TR-55 Channel
Flow Area
Wetted Perimeter
Hydraulic Radius
Slope
Mannings n
Hydraulic Length
Avg.Velocity
8.0000 sq.ft
8.47 ft
.94 ft
003500 ft/ft
.0450
765.00 ft
1.89 ft/sec
Segment #6 Time: 6.76 min
------------------------------------------------------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... OFFSITE-AF-PRE
Page 5.25
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Segment #7: Tc: TR-55 Channel
Flow Area
Wetted Perimeter
Hydraulic Radius
Slope
Mannings n
Hydraulic Length
Avg.Velocity
12.5600 sq.ft
12.56 ft
1.00 ft
.017400 ft/ft
.0130
710.00 ft
15.12 ft/sec
Segment #7 Time: .78 min
------------------------------------------------------------------------
-------------------------
-------------------------
Total Tc: 26.94 min
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

•
•
•
•
•
•
Type.... Tc Calcs
Name.... OFFSITE-AF-PRE
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= SCS TR-55 Sheet Flow ______________________________________________
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, ~
___= SCS TR-55 Shallow Concentrated Flow
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft
Page 5.26
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... OFFSITE-AF-PRE
Page 5.27
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
___= SCS Channel Flow _______________________
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0. 5)) / n
Tc = (Lf / V) / (3600sec/hr)
Where: R
Aq
Wp
V
Sf
n
Tc
Lf
Hydraulic radius
Flow area, sq.ft.
Wetted perimeter, ft
Velocity, ft/sec
Slope, ft/ft
Mannings n
Time of concentration, hrs
Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
•
i
•
•
•
•
Type.... Tc Calcs
Name.... OFFSITE-EXISTING
Page 5.28
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .035000 ft/ft
Avg.Velocity .15 ft/sec
Segment #1 Time: 10.76 min
------------------------------------------------------------------------
Segment #2: Tc: TR-55 Shallow
Hydraulic Length 61.00 ft
Slope .010000 ft/ft
Unpaved
Avg.Velocity 1.61 ft/sec
Segment #2 Time: .63 min
------------------------------------------------------------------------
Segment #3: Tc: TR-55 Channel
Flow Area
Wetted Perimeter
Hydraulic Radius
Slope
Mannings n
Hydraulic Length
Avg.Velocity
88.0000 sq.ft
35.30 ft
2.49 ft
.010000 ft/ft
.0300
261.00 ft
9.13 ft/sec
Segment #3 Time: .48 min
------------------------------------------------------------------------
Total Tc: 11.86 min
------------------------
------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
•
•
•
•
Type.... Tc Calcs
Name.... OFFSITE-EXISTING
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= SCS TR-55 Sheet Flow
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope,
___= SCS TR-55 Shallow Concentrated Flow
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Page 5.29
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... OFFSITE-EXISTING
Page 5.30
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
___= SCS Channel Flow __________________________________________________
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)
Where: R
Aq
wp
V
Sf
n
Tc
Lf
Hydraulic radius
Flow area, sq.ft.
Wetted perimeter, ft
Velocity, ft/sec
Slope, ft/ft
Mannings n
Time of concentration, hrs
Flow length, ft
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

•
•
•
•
Type.... Tc Calcs
Name.... OFFSITE-REAR-PRE
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 29hr P 3.6000 in
Slope .004000 ft/ft
Avg.Velocity .07 ft/sec
Segment #1 Time: 25.61 min
------------------------------------------------------------------------
Segment #2: Tc: TR-55 Shallow
Hydraulic Length 249.00 ft
Slope .009000 ft/ft
Unpaved
Avg.Velocity 1.02 ft/sec
Segment #2 Time: 4.07 min
------------------------------------------------------------------------
Segment #3: Tc: TR-55 Shallow
Hydraulic Length 990.00 ft
Slope .031800 ft/ft
Unpaved
Avg.Velocity 2.88 ft/sec
Segment #3 Time: 2.55 min
------------------------------------------------------------------------
Page 5.31
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

- Type.... Tc Calcs Page 5.32
- Name.... OFFSITE-REAR-PRE
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
w
Segment #4: Tc: TR-55 Channel
Flow Area 7.0000 sq.ft
Wetted Perimeter 10.32 ft
- Hydraulic Radius .68 ft
Slope .005700 ft/ft
i Mannings n .0450
Hydraulic Length 510.00 ft
Avg.Velocity 1.93 ft/sec
Segment #9-Time:------4.40-min

- Segment #5: Tc: TR-55 Channel
- Flow Area 8.0000 sq.ft
Wetted Perimeter 35.30 ft
Hydraulic Radius .23 ft
Slope .010000 ft/ft
- Mannings n .0300
Hydraulic Length 148.00 ft
. Avg.Velocity 1.85 ft/sec
- ---------------- --------- ----------------Segment-#5-Time-------134-min

Segment #6: Tc: TR-55 Channel
Flow Area 8.0000 sq.ft
Wetted Perimeter 8.97 ft
- Hydraulic Radius .94 ft
Slope .003500 ft/ft
Mannings n .0450
• Hydraulic Length 765.00 ft
• Avg.Velocity 1.89 ft/sec
- ---------------- --------- ----------------Segment-#6-Time-------6-76-min-
i
•
•
•
•
•
•
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Tc Calcs
Name.... OFFSITE-REAR-PRE
Page 5.33
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Segment #7: Tc: TR-55 Channel
Flow Area
Wetted Perimeter
Hydraulic Radius
Slope
Mannings n
Hydraulic Length
Avg.Velocity
12.5600 sq.ft
12.56 ft
1.00 ft
.017900 ft/ft
.0130
710.00 ft
15.12 ft/sec
Segment #7 Time: .78 min
------------------------------------------------------------------------
Total Tc: 45.51 min
-------------------------
-------------------------
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

i
•
•
Type.... Tc Calcs
Name.... OFFSITE-REAR-PRE
Page 5.34
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= SCS TR-55 Sheet Flow ______________________________________________
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope,
___= SCS TR-55 Shallow Concentrated Flow _____________________________°_
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
Bentley Systems, Inc.
3:20 PM 5/31/2007

Type.... Tc Calcs
Name.... OFFSITE-REAR-PRE
Page 5.35
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
___= SCS Channel Flow __________________________________________________
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)
Where: R
Aq
Wp
V
Sf
n
Tc
Lf
Hydraulic radius
Flow area, sq.ft.
Wetted perimeter, ft
Velocity, ft/sec
Slope, ft/ft
Mannings n
Time of concentration, hrs
Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... ONSITE
Page 5.36
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: User Defined
Segment #1 Time: 5.00 min
------------------------------------------------------------------------
-------------------------
-------------------------
Total Tc: 5.00 min
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... ONSITE
Page 5.37
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= User Defined
Tc = Value entered by user
Where: Tc = Time of concentration
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
•
•
•
•
s
Type.... Tc Calcs
Name.... POI 2 PRE-DEV
Page 5.38
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .020000 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: 13.45 min
------------------------------------------------------------------------
Segment #2: Tc: TR-55 Shallow
Hydraulic Length 367.00 ft
Slope .021800 ft/ft
Unpaved
Avg.Velocity 2.38 ft/sec
Segment #2 Time: 2.57 min
------------------------------------------------------------------------
Segment #3: Tc: TR-55 Channel
Flow Area 88.0000 sq.ft
Wetted Perimeter 35.30 ft
Hydraulic Radius 2.49 ft
Slope .010000 ft/ft
Mannings n .0300
Hydraulic Length 410.00 ft
Avg.Velocity 9.13 ft/sec
Segment #3 Time: .75 min
------------------------------------------------------------------------
Total Tc: 16.77 min
-------------------------
-------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
Bentley Systems, Inc.
3:20 PM 5/31/2007

•
•
•
•
i
•
Type.... Tc Calcs
Name.... POI 2 PRE-DEV
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= SCS TR-55 Sheet Flow -----___
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, ~
___= SCS TR-55 Shallow Concentrated Flow _______________________________
Unpaved surface:
V = 16.1395 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft
Page 5.39
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

•
•
•
•
i
•
•
•
•
•
•
r
•
•
•
•
•
•
•
•
•
•
•
Type.... Tc Calcs
Name.... POI 2 PRE-DEV
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE .
___= SCS Channel Flow __________________________________________________
R = Aq / Wp
V = (1.99 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)
Where: R =Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft
Page 5.40
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... PRE 12" RCP
Page 5.41
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
........................................................................
........................................................................
TIME OF CONCENTRATION CALCULATOR
........................................................................
........................................................................
Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .020000 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: 13.45 min
------------------------------------------------------------------------
Segment #2: Tc: TR-55 Shallow
Hydraulic Length 255.00 ft
Slope .015700 ft/ft
Unpaved
Avg.Velocity 2.02 ft/sec
Segment #2 Time: 2.10 min
------------------------------------------------------------------------
Segment #3: Tc: TR-55 Channel
Flow Area 8.0000 sq.ft
Wetted Perimeter 8.47 ft
Hydraulic Radius .94 ft
Slope .022200 ft/ft
Mannings n .1300
Hydraulic Length 630.00 ft
Avg.Velocity 1.64 ft/sec
Segment #3 Time: 6.39 min
------------------------------------------------------------------------
Total Tc: 21.94 min
------------------------
------------------------
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... PRE 12" RCP
Page 5.42
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
------------------------------------------------------------------------
Tc Equations used...
------------------------------------------------------------------------
___= SCS TR-55 Sheet Flow
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope,
___= SCS TR-55 Shallow Concentrated Flow
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Tc Calcs
Name.... PRE 12" RCP
Page 5.93
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
___= SCS Channel Flow __________________________________________________
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)
Where: R = Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Runoff CN-Area
Name.... ACROSS 55-POST
Page 6.01
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres ~C $UC CN
-------------------------------- ---- --------- ----- ----- ------
Pasture, grassland, or range - fair 69 2.231 69.00
Impervious Areas - Paved parking lO 98 1.711 98.00
COMPOSITE AREA & WEIGHTED CN ---> 3.942 81.59 (82)
...........................................................................
...........................................................................
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Runoff CN-Area
Name.... ACROSS 55-PRE
Page 6.02
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALLS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres $C %UC CN
-------------------------------- ---- --------- ----- ----- ------
Pasture, grassland, or range - fair 69 3.942 69.00
COMPOSITE AREA & WEIGHTED CN ---> 3.942 69.00 (69)
...........................................................................
...........................................................................
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Runoff CN-Area
Name.... EX SITE 48" PRE
Page 6.03
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres $C $UC
-- CN
------
-------------------------------- -
Pasture, grassland, or range - fair ---
69 ---------
13.287 ----- --- 69.00
Impervious Areas - Paved parking lO 98 .252 98.00
Woods - good 55 6.001 55.00
COMPOSITE AREA & WEIGHTED CN ---> 19.540 65.07 (65)
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Runoff CN-Area
Name.... EX SITE POST
Page 6.04
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres $C gUC CN
-------------------------------- ---- --------- ----- ----- ------
Impervious Areas - Paved parking l0 98 24.100 98.00
Open space (Lawns parks etc.) - Goo 61 6.060 61.00
COMPOSITE AREA & WEIGHTED CN ---> 30.160 90.57 (91)
...........................................................................
...........................................................................
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Runoff CN-Area
Name.... EX-SITE 18" PRE
Page 6.05
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres $C $UC
-
--- CN
------
-------------------------------- ----
woods - good 55 ---------
.634 ---
- -- 55.00
Other Agricultural Lands - Pasture, 61 2.543 61.00
COMPOSITE AREA & WEIGHTED CN --->
........................................
........................................ 3.177
..........
..........
............
............ 59.80 (60)
.............
.............
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Runoff CN-Area
Name.... OFF-REAR-POST
Page 6.06
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C $UC
-- ----- CN
------
-------------------------------- -
Pasture, grassland, or range - fair ---
69 ---------
7.764 --- 69.00
Impervious Areas - Paved parking lO 98 .040 98.00
Woods - good 55 2.007 55.00
COMPOSITE AREA & WEIGHTED CN --->
....................................
....................................
....
.... 9.811
..........
..........
............
............ 66.25 (66)
.............
.............
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Runoff CN-Area
Name.... OFFSITE-AF-POST
Page 6.07
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C $UC CN
-------------------------------- ---- --------- ----- ----- ------
Pasture, grassland, or range - fair 69 6.585 69.00
Impervious Areas - Paved parking l0 98 1.818 98.00
COMPOSITE AREA & WEIGHTED CN ---> 8.403 75.27 (75)
...........................................................................
...........................................................................
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Runoff CN-Area
Name.... OFFSITE-AF-PRE
Page 6.08
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres ~C RUC
-
- CN
------
-------------------------------- ----
Pasture, grassland, or range - fair 69 ---------
6.585 ----- --
- 69.00
Impervious Areas - Paved parking l0 98 1.818 98.00
COMPOSITE AREA & WEIGHTED CN --->
........................................
........................................ 8.403
..........
..........
............
............ 75.27 (75)
.............
.............
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Runoff CN-Area
Name.... OFFSITE-EXISTING
Page 6.09
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres gC RUC CN
-------------------------------- ---- --------- ----- ----- ------
Pasture, grassland, or range - fair 69 .480 69.00
Woods - good 55 4.000 55.00
COMPOSITE AREA & WEIGHTED CN ---> 4.480 56.50 (57)
...........................................................................
...........................................................................
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Runoff CN-Area
Name.... OFFSITE-REAR-PRE
Page 6.10
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC
-- CN
------
--------------------------------
Pasture, grassland, or range - fair ----
69 ---------
7.370 ----- --- 69.00
Impervious Areas - Paved parking l0 98 .040 98.00
woods - good 55 2.007 55.00
COMPOSITE AREA & WEIGHTED CN --->
...................................
...................................
.....
..... 9.417
..........
..........
............
............ 66.14 (66)
.............
.............
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Runoff CN-Area
Name.... ONSITE
Page 6.11
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres ~C RUC CN
-------------------------------- ---- --------- ----- ----- ------
Impervious Areas - Paved parking l0 98 3.474 98.00
Open space (Lawns,parks etc.) - Goo 61 .903 61.00
COMPOSITE AREA & WEIGHTED CN ---> 4.377 90.37 (90)
...........................................................................
...........................................................................
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Runoff CN-Area
Name.... POI 2 PRE-DEV
Page 6.12
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description CN
--
------------------------
---- -
- acres gC RUC CN
-
-
-
-
Woods - good 55 ---------
8.171 ----- ----- ------
55.00
Pasture, grassland, or range - fair 69 3.508 69.00
COMPOSITE AREA & WEIGHTED CN --->
........................................
........................................ 11.679
..........
..........
............
............ 59.21 (59)
.............
.............
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Runoff CN-Area
Name.... PRE 12" RCP
Page 6.13
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
RUNOFF CURVE NUMBER DATA
..........................................................................
..........................................................................
Impervious
Area Adjustment Adjusted
Soil/Surface Description
-------------------------------- CN
- acres ~C $UC CN

Pasture, grassland, or range - fair --
-
69 ---------
6.316 ----- ----- ------
69.00
woods - good 55 .162 55.00
Impervious Areas - Paved parking lO 98 .167 98.00
COMPOSITE AREA & WEIGHTED CN --->
....................................
...................................
....
..... 6.645
..........
..........
............
............ 69.39 (69)
.............
.............
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Vol: Elev-Area
Name.... WETLAND 1
Page 7.01
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum
(ft)
------------ (sq.in) (sq.ft)
--------------------- (sq.ft)
---------------- (ac-ft)
---------- (ac-ft)
-------------
430.00 ----- 79554 0 .000 .000
431.00 ----- 77739 228923 1.798 1.748
432.00 ----- 80981 238063 1.822 3.570
433.00 ----- 84279 297874 1.897 5.466
434.00 ----- 87634 257853 1.973 7.440
435.00 ----- 91045 268002 2.051 9.490
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Areal + sq.rt.(Areal*Area2))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 =Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

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Type.... Vol: Elev-Area
Name.... WETLAND 2
Page 7.02
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
Elevation Planimeter Area Al+A2+sgr(A1*A2) Volume Volume Sum
(ft) (sq.in) (sq.ft)
-- (sq.ft)
---------------- (ac-ft)
---------- (ac-ft)
-------------
------------
451.00 -------------------
----- 12567 0 .000 .000
452.00 ----- 14185 40104 .307 .307
453.00 ----- 15860 45049 .345 .652
459.00 ----- 17593 50157 .384 1.035
455.00 ----- 19382 55441 .424 1.460
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.
Volume = (1/3) * (EL2-EL1) * (Areal + Areal + sq.rt.(Areal*Area2))
where: EL1, EL2 = Lower and upper elevations of the increment
Areal,Area2 = Areas computed for EL1, EL2, respectively
Volume = Incremental volume between EL1 and EL2
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Outlet Input Data
Name.... Wetland 1 Outlet
Page 8.01
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
REQUESTED POND WS ELEVATIONS:
Min. Elev.= 430.00 ft
Increment = .50 ft
Max. Elev.= 935.00 ft
OUTLET CONNECTIVITY
---> Forward Flow Only (Upstream to DnStream)
<--- Reverse Flow Only (DnStream to Upstream)
<---> Forward and Reverse Both Allowed
Structure
----------------- No.
---- Outfall
------- E1, ft
------
- E2, ft

Weir-Rectangular
W1
--->
CO -
-
431.350 ---------
435.000
Inlet Box RO ---> CO 432.150 435.000
Orifice-Circular 00 --'-> CO 430.000 435.000
Culvert-Circular CO ---> TW 426.500 435.000
Weir-Rectangular WO ---> TW 433.500 435.000
TW SETUP, DS Channel
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Outlet Input Data
Name.... Wetland 1 Outlet
Page 8.02
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
OUTLET STRUCTURE INPUT DATA
Structure ID
Structure Type
--------------
# of Openings
Crest Elev.
Weir Length
Weir Coeff.
W1
Weir-Rectangular
----------------
1
931.35 ft
8.00 ft
3.200000
Weir TW effects (Use adjustment equation)
Structure ID = RO
Structure Type =
- Inlet Box
---------------
-----------------
-
# of Openings = --
1
Invert Elev. = 432.15 ft
Orifice Area = 36.0000 sq.ft
Orifice Coeff. _ .600
Weir Length = 19.00 ft
Weir Coeff. = 3.200
K, Reverse = 1.000
Mannings n = .0000
Kev,Charged Riser = .000
Weir Submergence = No
Structure ID = 00
Structure Type = Orifice-Circular
------------------------------------
# of Openings = 1
Invert Elev. = 430.00 ft
Diameter = 12.00 in
Orifice Coeff. _ .600
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Outlet Input Data
Name.... Wetland 1 Outlet
Page 8.03
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
OUTLET STRUCTURE INPUT DATA
Structure ID = CO
Structure Type
------------------ = Culvert-Circular
------------------
No. Barrels = 1
Barrel Diameter = 30.00 in
Upstream Invert = 426.50 ft
Dnstream Invert = 426.00 ft
Horiz. Length = 80.00 ft
Barrel Length = 80.00 ft
Barrel Slope = .00625 ft/ft
OUTLET CONTROL DATA...
Mannings n = .0130
Ke = .2000
Kb = .009217
Kr = .2000
HW Convergence = .001
(forward entrance loss)
(per ft of full flow)
(reverse entrance loss)
+/- ft
INLET CONTROL DATA...
Equation form = 1
Inlet Control K = .0045
Inlet Control M = 2.0000
Inlet Control c = .03170
Inlet Control Y = .6900
T1 ratio (HW/D) _ .000
T2 ratio (HW/D) = 1.194
Slope Factor = -.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 926.50 ft ---> Flow = 27.16 cfs
At T2 Elev = 429.99 ft ---> Flow = 31.05 cfs
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Outlet Input Data
Name.... Wetland 1 Outlet
Page 8.04
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE .
OUTLET STRUCTURE INPUT DATA
Structure ID
Structure Type
--------------
# of Openings
Crest Elev.
Weir Length
weir Coeff.
WO
Weir-Rectangular
----------------
1
433.50 ft
35.00 ft
3.200000
Weir TW effects (Use adjustment equation)
Structure ID = TW
Structure Type = TW SETUP, DS Channel
------------------------------------
FREE OUTFACE CONDITIONS SPECIFIED
CONVERGENCE TOLERANCES...
Maximum Iterations= 40
Min. TW tolerance = .O1 ft
Max. TW tolerance = .O1 ft
Min. HW tolerance = .O1 ft
Max. HW tolerance = .O1 ft
Min. Q tolerance = .00 cfs
Max. Q tolerance = .00 cfs
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Outlet Input Data
Name.... Wetland 2 Outlet
Page 8.05
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
REQUESTED POND WS ELEVATIONS:
Min. Elev.= 451.00 ft
Increment = .50 ft
Max. Elev.= 455.00 ft
OUTLET CONNECTIVITY
---> Forward Flow Only (Upstream to DnStream)
<--- Reverse Flow Only (DnStream to Upstream)
<---> Forward and Reverse Both Allowed
Structure
----------------- No.
---- Outfall
------- E1, ft
------ E2, ft

Weir-Rectangular
wl
--->
CO ---
452.000 ---------
455.000
Inlet Box RO ---> CO 453.000 955.000
Orifice-Circular 00 ---> CO 951.000 455.000
Culvert-Circular CO ---> TW 451.000 455.000
Weir-Rectangular WO ---> TW 454.000 955.000
TW SETUP, DS Channel
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Outlet Input Data
Name.... Wetland 2 Outlet
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
OUTLET STRUCTURE INPUT DATA
Structure ID
Structure Type
--------------
# of Openings
Crest Elev.
Weir Length
Weir Coeff.
Weir TW effects (Use adjustment equation)
Structure ID = RO
Structure Type
------------------ = Inlet Box
------------------
# of Openings = 1
Invert Elev. = 453.00 ft
Orifice Area = 16.0000 sq.ft
Orifice Coeff. _ .600
Weir Length = 15.17 ft
Weir Coeff. = 3.200
K, Reverse = 1.000
Mannings n = .0000
Kev,Charged Riser = .000
Weir Submergence = No
Structure ID = 00
Structure Type = Orifice-Circular
------------------------------------
# of Openings = 1
Invert Elev. = 451.00 ft
Diameter = 2.50 in
Orifice Coeff. _ .600
wl
weir-Rectangular
----------------
1
452.00 ft
.83 ft
3.200000
Page 8.06
S/N: DAYXYWJJ6M83
Bentley PondPack (10.00.027.00)
3:20 PM
Bentley Systems, Inc.
5/31/2007

Type.... Outlet Input Data
Name.... wetland 2 Outlet
Page 8.07
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
OUTLET STRUCTURE INPUT DATA
Structure ID = CO
Structure Type
----------------- = Culvert-Circular
-------------------
No. Barrels = 1
Barrel Diameter = 15.00 in
Upstream Invert = 451.00 ft
Dnstream Invert = 450.50 ft
Horiz. Length = 50.00 ft
Barrel Length = 50.00 ft
Barrel Slope = .01000 ft/ft
OUTLET CONTROL DATA...
Mannings n = .0130
Ke = .2000
Kb = .023225
Kr = .2000
HW Convergence = .001
(forward entrance loss)
(per ft of full flow)
(reverse entrance loss)
+/- ft
INLET CONTROL DATA...
Equation form = 1
Inlet Control K = .0095
Inlet Control M = 2.0000
Inlet Control c = .03170
Inlet Control Y = .6900
T1 ratio (HW/D) = 1.090
T2 ratio (HW/D) = 1.192
Slope Factor = -.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 452.36 ft ---> Flow = 4.80 cfs
At T2 Elev = 952.49 ft ---> Flow = 5.49 cfs
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Type.... Outlet Input Data
Name.... Wetland 2 Outlet
Page 8.08
File.... K:\LDEV\011919012 southpark village cds\Stormwater\DWQ REPORT AND CALCS 0507\PRE
OUTLET STRUCTURE INPUT DATA
Structure ID
Structure Type
--------------
# of Openings
Crest Elev.
Weir Length
Weir Coeff.
WO
Weir-Rectangular
----------------
1
954.00 ft
20.00 ft
3.200000
Weir TW effects (Use adjustment equation)
Structure ID = TW
Structure Type = TW SETUP, DS Channel
------------------------------------
FREE OUTFACE CONDITIONS SPECIFIED
CONVERGENCE TOLERANCES...
Maximum Iterations= 30
Min. TW tolerance = .O1 ft
Max. TW tolerance = .O1 ft
Min. HW tolerance = .Ol ft
Max. HW tolerance = .O1 ft
Min. Q tolerance = .10 cfs
Max. Q tolerance = .10 cfs
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

Appendix A
Index of Starting Page Numbers for ID Names
----- A -----
ACROSS 55-POST... 5.01, 6.01
ACROSS 55-PRE... 5.03, 6.02
----- E -----
EX SITE 48" PRE... 5.05, 6.03
EX SITE POST... 5.09, 6.04
EX-SITE 18" PRE... 5.11, 6.05
----- 0 -----
OFF-REAR-POST... 5.15, 6.06
OFFSITE-AF-POST... 5.19, 6.07
OFFSITE-AF-PRE... 5.23, 6.08
OFFSITE-EXISTING... 5.28, 6.09
OFFSITE-REAR-PRE... 5.31, 6.10
ONSITE... 5.36, 6.11
----- P -----
POI 2 PRE-DEV... 5.38, 6.12
PRE 12" RCP... 5.41, 6.13
----- T -----
TypeII 24hr 1... 4.01
----- w -----
Wake County, NC... 3.01
Watershed... 1.01, 2.01, 2.02, 2.03,
2.04, 2.05, 2.06
WETLAND 1... 7.01
Wetland 1 Outlet... 8.01
WETLAND 2... 7.02
Wetland 2 Outlet... 8.05
A-1
S/N: DAYXYWJJ6M83 Bentley Systems, Inc.
Bentley PondPack (10.00.027.00) 3:20 PM 5/31/2007

EROSION CONTROL CALCULATIONS

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Gj~„ Kimley-Hom
~~ and Assatiales, Inc.
EROSION CONTROL CALCS -CUSTOM BASIN
Project Information
Project Name: South Park Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date:
Checked by: DM Date:
Custom Basin #1
Drainage Area
10-year Runoff (Qto)
Surface Area Required
Volume Required
Sediment Trap Dimensions
Elevations & Areas
Provided
Spillway - tOYear Storm
Total, A,= 3.818 Ac
Disturbed, Ao= 3.818 Ac
C = 0.40
To = 5.00 min
Ito = 7.08 inlhr
Qio = 10.8 cfs
SA = 435 x Qto
SA = 4703 sf
VR = 1800 dlAc x Ao
VR = 6872.4 cf
L= 110 ft
W = 55 ft
D= 4 ft
Side Slopes = 3 :1
Ltop = 119 ft L to
Loot= 89 ft WtoP
WtoP= 64 ft W pot
Wpot = 34 ft L pot
Description Elevation
Top of Berm 455.5
Spillway 454.0
Bottom 450.5
SAP= 6,050 sf > 4,703
VP = 15,883 cf > 6,872
h = 0.5 ft
C„, = 3
Lw= 11.0 ft (sized to pass Qta) (10.0' Minimum)

C,~„ Kimley-Hom
~~ and Associates, Inc.
EROSION CONTROL CALCS -CUSTOM BASIN
Project Information
Project Name: South Park Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date:
Checked by: DM Date:
Custom Basin #2
Drainage Area
10-year Runoff (Q~o)
Surface Area Required
Volume Required
Sediment Trap Dimensions
Elevations 8 Areas
Provided
Spillway - 10Year Storm
Total, AT= 4.566 Ac
Disturbed, Ap= 4.352 Ac
C = 0.40
T~ = 5.00 min
Ira = 7.08 in/hr
Qto = 12.9 cfs
SA = 435 x Q,o
SA = 5625 sf
VR = 1800 cflAc x Ao
VR = 7833.6 cf
L = 110 ft
W = 55 ft
D= 4 ft
Side Slopes = 3 :1
LtoP = 119 ft
Lp,t = 89 ft
WtoP _ 64 ff
Wit= 34 ft
L to
WtaP
W boi
L~
Description Elevation
Top of Berm 455.5
Spillway 454.0
Bottom 450.5
SAP= 6,050 sf > 5,625
VP = 15,883 cf > 7,834
h = 0.5 ff
Cw = 3
LW = 13.0 ft (sized to pass Quo) (10.0' Minimum)

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~:~„ Kimley-Hom
\:~ and AssorJates, Inc.
EROSION CONTROL CALCS -CUSTOM BASIN
Project Information
Project Name: South Park Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date:
Checked by: DM Date:
Custom Basin #3
Drainage Area
10-year Runoff (Qto)
Surface Area Required
Volume Required
Sediment Trap Dimensions
Elevations & Areas
Provided
Spillway - 10Year Storm
Total, AT= 2.463 Ac
Disturbed, Ap= 2.463 Ac
C = 0.40
T~ = 5.00 min
Ito = 7.08 in/hr
Qua = 7.0 cfs
SA = 435 x Qto
SA = 3034 sf
VR = 1800 cflAc x Ao
VR = 4433.4 cf
L = 90 ft
W = 45 ft
D= 4 ft
Side Slopes = 3 :1
LtoP ° 99 ft
Lit= 69 ft
W„P = 54 ft
Wbot' 24 ft
L to
WtoP
W bot
L bot
DescAption Elevation
Top of Berm 455.5
Spillway 454.0
Bottom 450.5
SAP= 4,050 sf > 3,034
VP = 9985.5 cf > 4,433
h = 0.5 ft
C„, = 3
Lw= 10.0 ft (sized to pass Q,o) (10.0' Minimum)

•
~~_I, Kimley-Nom
-~ and Associates, Inc.
EROSION CONTROL CALCS -CUSTOM BASIN
Project Information
Project Name: _ South Park Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date:
Checked by: DM Date:
Custom Basin #4
Drainage Area
10-year Runoff (Qto)
Surface Area Required
Volume Required
Sediment Trap Dimensions
Elevations & Areas
Provided
Spillway - 10Year Storm
Total, AT= 2.559 Ac
Disturbed, Ap= 2.559 Ac
C = 0.40
T~ = 5.00 min
Ito = 7.08 in/hr
Quo = 7.2 cfs
SA = 435 x Q,o
SA = 3152 sf
VR = 1800 cf/Ac x Ap
VR = 4606.2 cf
L = 90 ft
W = 45 ft
D= 4 ft
Side Slopes = 3 :1
Ltov = 99 ft L to
Lam= 69 ft Wtov
WtoP = 54 ft W ~t
Wyot = 24 ft L yot
Description Elevation
Top of Berm 455.5
Spillway 454.0
Bottom 450.5
SAP= 4,050 sf > 3,152
VP = 9985.5 cf > 4,606
h = 0.5 ff
C„, = 3
Lw= 10.0 ft (sized to pass Q,a) (10.0' Minimum)

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~„ Kimley-Horn
\ ~ and Associates, Inc.
EROSION CONTROL CALCS (SKIMMER BASINS)
Project Information
Project Name: South Park Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date: 4/11/2007
Checked by: DM Date: 4/13/2007

Skimmer Basin #1
Drainage Area Total, AT= 5.185 Ac
Disturbed, Ap= 5.185 Ac
10-year Runoff (Qto) C = 0.40
T~ = 5.00 min
Ito = 7.08 in/hr
Qto = 14.7 cfs
Surface Area Required SA = 325sf x Qto
SA = 4,772 sf
Volume Required VR = 1800 cf/Ac x Ao
VR = 9,333 cf
Sediment Trap Dimensions L = 100 ft (Spillway Length)
W = 50 ft (Spillway Wtdth)
D = 4 ft (Depth of Storage)
Side Slopes = 3 :1
Lto
LtoP= 109 ft
Lmt = 79 ft Wto Went
WtoP= 59 ft Lent=
Wit= 29 ft
L!W Ratio= 2.0 :1 (must be 2:1 to 6:1)
Elevations Description Elevation
Top of Berm 465.50 (allow 1ft freeboard above spillway flow height)
Emergency Spillway 464.00
Cleanout Mark 462.25 (half of storege height)
Bottom 460.50
Provided SAP= 5,000 sf > 4,772
VP = 12,759.3 cf > 9,333
Emergency Spillway - 25 Year S1 125 = 7.78
Qzs = 16.14 cfs
h = 0.5 ft
Cw = 3
Lw = 16 ft (sized to pass Q25)

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Skimmer Basin #1 (Continued)
Skimmer Size
Dewatering Volume 12,759 d
Skimmer Size 2.5 in.
Average Head { h }: 0.167 ft
Skimmer
Size Head
2" 0.167 ft.
2.5" 0.167 ft.
3" 0.25 fl.
4" 0.275 ft.
5" 0.333 ft.
6" 0.417 ft.
Select:
Orifice Diameter { d }:
Area { A }:
Discharge Coefficient (C):
Flowrate { Q }:
Draw Down Time { T }:
2.5 in = 0.208
0.034 sq ft
0.60
Q =CA sgrt(2gh) = 0.067
190,224 seconds = 2.2
2.2
ft
cfs
days > 1 day
days < 3 days

•
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•
~ ~ Kimley-Horn
\ ~ I \ and Assoraates, Inc.
EROSION CONTROL CALCS (SKIMMER BASINS)
Project Information
Project Name: South Park Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date: 4!11/2007
Checked by: DM Date: 4/13/2007

Skimmer Basin #2
Drainage Area Total, AT= 9.208 Ac
Disturbed, Ao= 9.208 Ac
10-year Runoff (Qta) C = 0.40
To = 5.00 min
Ito = 7.08 in/hr
Qua = 26.1 cfs
Surface Area Required SA = 325sf x Qio
SA = 8,475 sf
Volume Required VR = 1800 cf/Ac x Ao
VR = 16,574 cf
Sediment Trap Dimensions L = 140 ft (Spillway Length)
W = 70 ft (Spillway Widlh)
D = 4 ft (Depth of Storage)
Side Slopes = 3 :1
Lto =
LtoP= 149 ft
Loot= 119 ft Wto Wont
WtoP= 79 ft Lo,t=
w„t= as n

L/W Ratio= 2.0 :1 (must be 2:1 to 6:1)
Elevations Description Elevation
Top of Berm 454.50 (allow 1ft freeboard above spillway flow height)
Emergency Spillway 453.00
Cleanout Mark 451.25 (half of storage height)
Bottom 449.50
Provided SAP= 9,800 sf > 8,475
VP = 27,354.3 cf > 16,574
Emergency Spillway - 25 Year S1 I25 = 7.78
Qzs ° 28.66 cfs
h= O.Sft
Cw = 3
Lw= 28 ft (sized to pass Q25)

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Skimmer Basin #2 (Continued)
Skimmer Size
Dewatering Volume 27,354 d
Skimmer Size 4.0 in.
Average Head { h }: 0.275 ft
Skimmer
Size Head
2" 0.167 ft.
2.5" 0.167 ft.
3" 0.25 ft.
4" 0.275 ft.
5" 0.333 ft.
6" 0.417 ft.
Select:
Orifice Diameter { d }:
Area { A }:
Discharge Coefficient (C):
Flowrate { Q }:
Draw Down Time { T }:
4 in = 0.333
0.087 sq ft
0.60
Q =CA sgrt(2gh) = 0.220
124,142 seconds = 1.4
1.4
ft
cfs
days > 1 day
days < 3 days

•
~~„ Kimley-Hom
\ ~ and Associates, Inc.
EROSION CONTROL CALCS (SKIMMER BASINS)
Project Information
Project Name: South Park Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date: 4/11/2007
Checked by: DM Date: 4/13/2007
Skimmer Basin #3
Drainage Area Total, AT= 6.405 Ac
Disturbed, Ao= 6.405 Ac
10-year Runoff (Dto) C = 0.40
T~ = 5.00 min
I,o = 7.08 in/hr
Quo = 18.1 cfs
Surtace Area Required SA = 325sf x Qto
SA = 5,895 sf
Volume Required VR = 1800 cf/Ac x Ao
VR = 11,529 cf
Sediment Trap Dimensions L = 110 ft (Spillway Length)
W = 55 ft (Spillway Width)
D = 4 ft (Depth of Storage)
Side Slopes = 3 :1
Lto =
Ltoc ° 119 ft
Lit= 89 ft Wto Went
Wtoo° 64 ft Lit=
W~= 34 ft
L/W Ratio= 2.0 :1 (must be 2:1 to 6:1)
Elevations Descriotion Elevation
Top of Berm 455.50 (allow tft freeboard above spillway flow height)
Emergency Spillway 454.00
Cleanout Mark 452.25 (half of storage height)
Bottom 450.50
Provided
Emergency Spillway - 25 Year Sf
SAP= 6,050 sf > 5,895
VP = 15,883.0 cf > 11,529
125 - 7.76
Qzs - 19.93 cis
h= 0.5ft
Cw = 3
Lw= 19 ft (sized to pass Q25)

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Skimmer Basin #3 IContinuedl
Skimmer Size
Dewatering Volume 15,883 d
Skimmer Size 3.0 in.
Average Head { h }: 0.250 ft
Skimmer
Size Head
2" 0.167 ft.
2.5" 0.167 ft.
3" 0.25 ft.
4" 0.275 ft.
5" 0.333 ft.
6" 0.417 ft.
Select:
Orifice Diameter { d }:
Area { A }:
Discharge Coefficient (C):
Flowrate { Q }:
Draw Down Time { T }:
3 in = 0.250
0.049 sq ft
0.60
O =CA sgrt(2gh) = 0.118
134,400 seconds = 1.6
1.6
ft
cfs
days > 7 day
days < 3 days

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~ ~„ Kimley-Horn
\ ~ arb Associates, Inc
EROSION CONTROL CALCS (RISER BASINS)
Project Information
Project Name: South Park Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date: 4/11/2007
Checked by: DM Date: 4/13/2007
Riser Basin #1
Drainage Area Total, AT= 41.316 Ac
Disturbed, Ao= 41.316 Ac
10-year Runoff (Qto) C = 0.40
To = 5.00 min
lio = 7.32 in/hr
Qto = 121.0 cfs
Surface Area Required SA = 435sf x Qto
SA = 52,623 sf
Votume Required VR = 1800 cf/Ac x Ac
VR = 74,369 cf
Sediment Trap Dimensions L = 200 ft (Riser Length)
W = 100 ft (Riser Width)
D = 2 ft (Depth of Storage)
Side Slopes = 3 :1
Ito =
Ltov = 221 ft
Ly,t= 188 ft Wto Went
Wtov° 121 ft I_cm=
Wcot= 88 ft
U1N Ratio= 2.0 :1 (must be 2:1 to 6:1)
Elevations Descriotion Elevation
Top of Berm 355.50 (allow tft freeboard above spilN/ay flow height)
Emergency Spillway 354.00
Riser Crest 352.00
Cleanout Mark 351.00 (half of storage height)
Boriom 350.00
Provided SAP= 20,000 sf > 52,623
VP = 36,544.0 cf > 74,369
Riser & Barrel h = 2.0 ft
Cw = 3.1
Riser Diameter Required = 53 D=(12*Q70)/(Cw*h1's*pi)
Barrel Diameter Required = 35 Determined from riser size
Riser Diameter Chosen: 18 in.
Barrel Diameter Chosen: 12 in.
Inlet Proportions(Figure 8.07b)
Barrel Size Riser Size
8" to 12" 18"
15" 24"
18" 24"
24" 30" I
30" 36" ~
36" 48"
42" 54"
46" 60"

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Riser Basin #1 IContinuedl
Anti-Floatation Device
Area:
Volume:
Factor of Safety:
Weight:
WT Req'd of Anti-Floatation Device:
Volume of Concrete Req'd:
Height Below Invert:
Volume Provided:
Emergency Spillway - 25 Year St Izs =
Qzs
h=
C„, _
Lw =
Outlet Barrel Dissipator Pad
1.8 sf (Water Displaced)
3.5 Cf (Water Displaced)
1.1
220.5 Ibs
242.6 Ibs
2.8 cf (Bouyant WT of Concrete =(15(}62.4) pcf)
1.75 ft
3.1 cf (Extend riser below outlet invert 8 fill with concrete)
8.94
147.75 cfs
0.5 ft
3
140 ft (sized to pass Q25)
Barrel Diameter d= 12 in
Dissipator Dimensions' Zone = 1
Stone Filling Class = A
Entry Width (3 X Do) = 3.0 ft
Length(4XDo)= 4.Oft
Width (La + Do) = 5.0 ft
Min. Thickness = 12 inches
Min. Stone Size= 3 inches
3.0
' All units are in feet
" Dissipator pad designed for full flow of pipe

Riser Basin #1 IContinuedl
Skimmer Size
Lrrser = 200 ft
W~,e,= 100 ft
L~,aa~o~, = 194 ft
W~,~a„o,~= 94 ft
24 hr. Dewatering Volume= 19,118 d
72 hr. Dewatering Volume= 36,544 d
Draw Down Times: 1 to 3 days
or 86,400 to 259,200 seconds
Flow Rates { O }: 0.221 to 0.141 cfs
Skimmer Size 3.0 in.
Average Head { h }: 0.250 ft
Skimmer
Size Head
2" 0.167 ft.
2.5" 0.167 ft.
3" 0.25 ft.
4" 0.275 ft.
5" 0.333 ft.
s° o.av n.
Discharge Coefficient: 0.60
1 Day: A = O / (C sgrt(2gh)) = 0.092 sq ft
diameter { d }: 0.342 ft = 4.11 in
3 Day: A = O / (C sgrt(2gh)) = 0.059 sq ft
diameter { d }: 0.273 ft = 3.28 in
Select:
Orifice Diameter { d }; 3 in = 0.250 ft
Area { A }: 0.049 sq ft
Flowrate { Q }: O =CA sgrt(2gh) = 0.118 cfs
Draw Down Time { T }: 161,774 seconds = 1.9 days > 1 day
Draw Down Time { T }: 309,231 seconds = 3.6 days < 3 days

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/~~ Kimley-Horn
`~ and Associates, Inc.
EROSION CONTROL CALCS (RIP-RAP CALCULATIONS)
Project Information
Project Name: South Pa rk Village
KHA Project #: 11919012
Designed by: JDA Date: 4/2/2007
Revised by: JDA Date: 4/11/2007
Checked by: Date: 4 7

Wetland 1 Outlet
Pipe Diameter d= 30 in
Pipe Slope s= 0.625
Manning's number n= 0.013
Flow Q= 57.78 cfs
Velocity V = 11.78 ft/s
Dissipator Dimensions ' Zone = 3
Stone Filling Class = 1
Entry Width (3 X Do) = 7.5 ft
Length (8 X Do) = 20.0 ft
Width (La + Do) = 22.5 ft
Min. Thickness = 24 inches
Min. Stone Diameter- 13 inches
i
Trap_Basin Calcs.xls
5/31 /2007
Page 18 of 20
' All units are in feet
" Dissipator pad designed for full flow of pipe

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/ ~„ Kimley-Hom
\ ~ and Associates, Inc.
Wetland 2 Outlet
Existing 18" Culvert
Trap_Basin Calcs.xls
Pipe Diameter
Pipe Slope
Manning's number
Flow
Velocity
Dissipator Dimensions *
Pipe Diameter
Pipe Slope
Manning's number
Flow
Velocity
Dissipator Dimensions
d=
s=
n=
Q=
V=
Zone =
Stone Filling Class =
Entry Width (3 X Do) _
Length (4 X Do) _
Width (La + Do) _
Min. Thickness =
Min. Stone Diameter=
3.
d=
s=
n=
0=
V=
Zone =
Stone Filling Class =
Entry Width (3 X Do) _
Length (6 X Do) _
Width (La + Do) _
Min. Thickness =
Min. Stone Diameter--
4
5/31 /2007
15 in
1.00
0.013
7.01 cfs
5.71 ft/s
1
A
3.8 ft
5.0 ft
6.3 ft
12 inches
3 inches
18 in
1.68
0.013
8.16 cfs
8.04 ft/s
2
B
4.5 ft
9.0 ft
10.5 ft
22 inches
6 inches
Page 19 of 20
' All units are in feet
'* Dissipator pad designed for full Flow of pipe
`All units are in feet
" Dissipator pad designed for full flow of pipe

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/ ~„ Kimley-Hom
~ and Associates, Inc.
FES 1
FES 40
Trap_Basin Calcs.xls
Pipe Diameter
Pipe Slope
Manning's number
Flow
Velocity
Dissipator Dimensions '
Pipe Diameter
Pipe Slope
Manning's number
Flow
Velocity
Dissipator Dimensions
d=
s=
n=
Q=
V=
Zone =
Stone Filling Class =
Entry Width (3 X Do) _
Length (8 X Do) _
Width (La + Do) _
Min. Thickness =
Min. Stone Diameter=
1;
d=
S=
n=
Q=
V=
Zone =
Stone Filling Class =
Entry Width (3 X Do) _
Length (6 X D°) _
Width (La + Do) _
Min. Thickness =
Min. Stone Diameter-
9.
5/31 /2007
60 in
0.91
0.013
223.18 cfs
14.32 ft/s
3
1
15.0 ft
40.0 ft
45.0 ft
24 inches
13 inches
36 in
0.5
0.013
33.02 cfs
7.22 ft/s
2
B
9.0 ft
18.0 ft
21.0 ft
22 inches
6 inches
Page 20 of 20
' All units are in feet
" Dissipator pad designed for full flow of pipe
' All units are in feet
" Dissipator pad designed for full flow of pipe

~~© lCmley-Hom
~ ark Assccletes, Inc.
Channel Design
TRAPEZOIDAL SHAPE
T
rn
~~ b T e
Channel Location: Channel 1
Estimate 10-vr Peak Runoff:
Rational C 0.90
Intensi (in/hr) 7.08
Draina a Area 1.81 ac
Quo 11.53 cfs
Additional Flow 0.00 cfs
Quo Total, Qdesign 11.53 Cfs
Channel Information:
Channel Bottom Width, b 3.0 ft
Side Slope (x:1) 3.0
Channel Slo e, S 0.021 ft/ft
Flow Depth, d 0.91 ft
Selected Channel Linina:
Selected Channel Linin Rock Rip Ra 6"
Maximum Permissible Velocity {Vmax} fps 6
Permissible Shear Stress {tp} (psf) 2.00
Calculations:
e 2.7 ft
Side Slo a Len th, m 2.9 ft
Top Width, T 8.5 ft
Channel Area, A 5.21 sq ft
Wetted Perimeter, PW 8.76 ft
H draulic Radius, Rh 0.60 ft
Mannings "n" 0.069
Calculated Flow Rate, Qcaic 11.63 cfs
Calculated Velocit , V~aic 2.23 fps
Calculated Shear Stress, tcaic 1.21 psf
Q talc ~ Q design? yeS
~/ talc < ~/ max? yeS
t talc < t p? yeS

©~~ EGrnley-Nom
- and AssQCtiates, Inc.
Channel Design
TRAF'EZOIDA.L SHAPE
T
~\ d
rr~
~~~-- t, --;-- E
Channel Location: Channel 2
Estimate 10-vr Peak Runoff:
Rational C 0.90
Intensi (in/hr) 7.08
Draina a Area 1.17 ac
Qto 7.46 cfs
Additional Flow 0.00 cfs
Qto Total, Qdesign 7.46 Cfs
Channel Information:
Channel Bottom Width, b 2.0 ft
Side Slo a x:1 3.0
Channel Slo e, S 0.012 ft/ft
Flow De th, d 0.55 ft
Selected Channel I ininn•
Selected Channel Linin North American Green - S75
Maximum Permissible Veloci max (fps 5
Permissible Shear Stress {tp} (psf) 0.45
Calculations:
e 1.7 ft
Side Slope Len th, m 1.7 ft
Top Width, T 5.3 ft
Channel Area, A 2.01 sq ft
Wetted Perimeter, Pw 5.48 ft
Hydraulic Radius, Rh 0.37 ft
Mannin s "n" 0.022
Calculated Flow Rate, Qcaie 7.60 cfs
Calculated Veloci , Vcaie 3.78 fps
Calculated Shear Stress, teak 0.41 psf
Q talc ? Q designs yeS
V talc S V max? yeS
t talc S t p~ yeS
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APPENDICES

Appendices
Table 8.03e Runoff curve numbers of urban areas'
Curve number for
Cover Description hydrologic soil group
Cover type and hydrologic condition Average percent A g C D
impervious areaz
Fully developed urban areas (vegetation established)
Open space (lawns, parks, golf courses, cemeteries, -etc.) 3:
Poor condition (grass cover < 50%) ............................. 68 79 86 89
Fair condition (grass cover 50% to 75%) ..................... 49 69 79 84
Good condition (grass cover > 75%) ............................ 39 61 74 80
Impervious areas:
Paved parking lots, roofs, driveways, etc.

(excluding right-of--way) ............................................... g8 98 98 98
Streets and roads:
Paved; curbs and storm sewers (excluding

right-of-way) ........:.:.:.................:....:.......:...................... g8 98 98 98
Paved; open ditches (including right-of-way) ................ 83 89 92 93
Gravel (including right-of--way) , ..................................... 76 85 89 91
Dirt (including right-of--way) ........................................... 72 82 87 89
Urban. districts:
Commercial and business ................................................. 85 89 92 94 95
Industrial ..........:................................................................ 72 81 88 91 93
Residential districts by average lot size:
1/8 acre or less (town houses) ......................................... 65 77 85 90 92
1 /4 acre ............................................................................ 38 61 75 83 87
1/3 acre ............................................................................. 30 57 72 81 86
1 /2 acre ............................................................................. 25 54 70 80 85
1 acre ............................................................................... 20 51 68 79 84
2 acres .............................................................................. 12 46 65 77 82
Developing urban areas
Newty graded areas

(pervious areas only, no vegetation) ° ............................ 77 86 91 94
Idle lands (CN's are determined using cover types
similar to those in table 2-2c).
1. Average runoff condition, and la = 0.2S.
2. The average percent impervious area shown was used to develop the composite CN's. Other assumptions are as follows: impervious
areas are directly connected to the drainage system, impervious areas have a CN of 98, and pervious areas are considered equivalent
to open space in good hydrologic condition. CN's for other combinations of conditions may be computed using Figure 8.03c or 8.03d.
3. CN's shown are equivalent to those of pasture. Composite CN's may be computed for other combinations of open space cover type.
4. Composite CN's to use for the design of temporary measures during grading and construction should be computed using Figure 8.03c
or 8.03d based on the degree of development (impervious area percentage) and the CN's for the newly graded pervious areas.
Rev. 6/06
8.03.15

Appendices
Table 8.03g Runoff curve numbers for other agriculture lands'
Curve numbers for
- Cover description hydrologic soil groups
Hydrologic
Cover type conditions3 A B C D
Pasture, grassland, or range- Poor 68 79 86 89
continuous forage for grazing. 2
Fair 49 69 79 84
Good 39 61 74 80
Meadow--continuous grass, protected - 30 58 71 78
from grazing and generally mowed for
hay.
Brush-brush-weed-grass mixture with Poor 48 67 77 83
brush the major element. 3
Fair 35 56 70 77
Good 30 a 48 65 73
Woods-grass combination (orchard or Poor 57 73 82 86
tree farm). s
Fair 43 65 76 82
Good- 32 58 72 79
Woods. s Poor 45 66 77 83
Fair 36 60 73 79
Good 30 a 55 70 77
Farmsteads-buildings, lanes; - 59 74 82 86
driveways, and surrounding lots.
1 Average runoff condition, and 1,= 0.2S.
2 Poor.- <50% ground cover or heavily grazed with no mulch.
Fair. 50 to 75% ground cover and not heavily grazed.
Good: > 75% ground cover and lightly or only occasionally grazed.
3 Poor. <50% ground cover.
Fair. 50 to 75% ground cover.
Good: >75% ground cover.
4 Actual curve number is less than 30; use CN = 30 for runoff computations.
5 CN's shown were computed for areas with 50% woods and 50% grass (pasture) cover. Other combinations of
conditions may be computed from the CN's for woods and pasture.
6 Poor. Forest titter, small trees, and brush are destroyed by heavy grazing or regular burning.
Fair. Woods are grazed but not burned, and some forest litter covers the soil.
Good: Woods are protected from grazing, and litter and brush adequately cover the soil.
Rev. 6/06 8.03.17

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~A~NFAtL ~NtENS~ry VgcuEs
Appendices
Raleig h,~North Carolina 35.8706N, 78.7864W
ARI* 5 min. 10 min. 15 min. 30 min. 60 min. 120 min. 3 hr. 6 hr. 12 hr. 24 hr.
(years)
2 5.58 4.46 3.74 2.58 1.62 0.94 0.66 0.40 0.24 0.14
10 7.08 5.66 4.78 3.46 2.25 1.33 0.95 0.58 0.34 0.021
25 7.78 6.19 5.24 3.88 2.58 1.54 1.11. 0.68 0.41 0.24
100 8.64 6.86 5.78 4.43 3.05 1.85 1.36 0.84 0.51 0.30
NG p6N~ " M14~uAc
Exhibit 2 by H. R Malcom, P.E.
C. E. Dept, NCSU
Depth-Duration-Frequency Table Raleigh, NC
Location: -~ Raleigh-Durham, NC
Return Period j
Duration 2-yr 5-yr 10-yr 25-yr 50-yr 100-yr

5 min 0.48 0.55 0.60 0.68 0.75 0.81
10 min 0.79 0.92 ~ 1.02 ~ 1.17 _ 1.28- ~ 1.40
15 min 1.01 1.18 1.31 1.51 1.66 1.81
30 min 1.35 1.64 1.85 2.16 2.40. 2.64
60 min 1.70 2.12. i 2:41 2.84 3.17 3.50
2 hr 1.91 2.40 2.74 3.23 < 3:61 4.00.
3 hr 2.12 2.68 3.07 ~ 3.62 ~ 4.06 ' 4.49
6 hr 2.65 3.:~~8 3.90 4.62 5:19 ~ 5.75
12 hr 3.13 4.02 4.64 5.52 .6.20, .6.88
24 hr 3.60 4.65 5.38 6.41 7.21 x.00

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