20070776 Ver 3_More Info Received_20081117

I? WADETRIM
November 14, 2008
401 Oversite/Express Review Permitting Unit
NCDENR - Division of Water Quality
Parkview Building
2321 Crabtree Boulevard, Suite 250
Raleigh, North Carolina 27604
Attention: Ms. Annette Lucas
Re: Waynesville Commons, Haywood County
DWQ Project # 07-0776 ve.9, 3
Lot 2 - Best Buy
Dear Ms. Lucas:
DO
NOV 1 7 2008
DENR . WATER QUALITY
WETLANDS AND STORMWATER BRANCH
In response to your October 30, 2008 comment letter received by our office on November 4,
2008, we offer the following comments:
1. Overall Site
a. Our previous submittal included a new Sheet C-2.2 which is a drainage map
indicating drainage boundary, storm pipes, inlets and catch basins, treatment
areas, bypass structures, bypass pipes, and outlets for this outparcel. We have
revised this sheet accordingly based on the comments below.
2. Wet Detention Pond
a. We have converted this basin to an excessively large forebay and storage basin.
The basin is now an aesthetic pond, but also provides as a forebay and holds our
water quality volume prior to entering the sand filter.
b. We have added a sand filter located under the parking lot similar to the other two
sand filters for this development. The outlet orifice directs the water quality
volume to a sand filter for additional treatment. We have added details for this
sand filter on Sheet C-2.1. Piping to and from the sand filter are detailed on
Sheet C-2.1 and C-3.0. The bypass structure remains as previously designed to
allow flows in excess of the water quality volume to by pass the forebay and
storage pond.
c. The sand filter is 14ft by 30ft. The filter is fed with 6" pipes a manifold and 3
row of 6" perforated pipe in a layer of washed stone. A minimum of 2 feet of
sand is located below the layer of washed stone and 6" distribution piping. At
the bottom of the filter is 3 rows of 4" perforated piping, a header, and discharge
pipe to the bypass piping. The bed is wrapped in geotextile. The stone and sand
are separated with geotextile. Cleanouts have been provided for all laterals. The
Wade Trim, Inc. 828.665.1288
1200 Ridgefield Boulevard 828.665.9566 fax
Suite 145 www.wadetrim.com
Asheville, NC 28806

Page 2
Ms. Annette Lucas
November 14, 2008
bottom of the filter and collection piping slopes at 0.50%. The bottom of the
filter is at least 2 feet above the SHWT. The specification for the perforated
piping has been referenced on the plan. The perforated piping is standard ADS
pipe with a sock. The Stormwater maintenance easement shown on Sheet C-1.0
has been expanded to include the sand filter area. We have included our
calculations, supplement, Hydrocad modeling results, and technical notes for the
perforated pipe. A signed operation and maintenance agreement is forthcoming
under separate cover.
Sand Filter behind building
a. The sand filter is open at the surface, but the bottom and sides of the filter are
closed because the design calls for a PVC liner. With a PVC liner, the system is
closed with respect to ground water.
b. We have adjusted the slopes of the discharge piping to 0.50% minimum. This
was accomplished by elevating or raising the entire sand filter up 0.5 feet. This
change in vertical elevation did not affect the volumes, capacities, or design
function of the system. We have re-run the Hydrocad modeling and re-checked
our calculations to ensure this change did not affect design. We have enclosed
new copies of these reports and calculations for your file. The 6" outlet at the
splitter box is now 0.15 feet higher than the 15" bypass pipe. We do not expect
clogging to occur with this change in elevation.
c. We have added a second 4" drain below the sand filter inclusive of inspection
ports and cleanouts. We have specified the perforations by referencing the
manufactures technical bulletin on the plans. We have included a copy of this
specification for your file/review. On the Section B-B view on Sheet C-2.1, we
have indicated the spacing of the laterals.
d. Our sand filter is unusual in shape as the flow enters at the long end. Even flow
distribution which could result in overloading and clogging at the leading edge of
the sand filter was a concern during the design. To mitigate this concern, we
propose to use a pipe distribution system, mimicking an underdrain system, to
evenly distribute flow from the sediment basin (forebay) to sand filter media (per
section 11.3.4 of the BMP manual). Calculations for this design were included in
our previous submittal.
e. We have consulted with our geotechnical engineer on your concern regarding the
side slopes. I have attached a copy of our correspondence with him. He has
indicated that the areas should hold up. He also indicated that some sloughing
and erosion is likely. However, please consider that the slopes are only about 2.5
to 3.5 feet tall, the slopes in the sand filter area are protected with PVC liner, and
the sediment basin are will have sod stapled to the slopes. Additionally, no
overland flow is directed to these slopes, only what rain falls from the sky on
these slopes. Also, the slopes in the sand filter area are covered with PVC,
eliminating the concern for erosion from water. The forebay has sod stapled on
the slopes which provides for immediate protection from erosion.
With respect to his comment regarding the wall, we have raised the sand filter 0.5
feet and the foundation for the wall is below the elevation of the sand in our
Page 3
Ms. Annette Lucas
November 14, 2008
filter. Loss of soil on the side slopes of the sand filter will not create a detriment
or unstable condition for the adjacent wall.
Additionally, the operation and maintenance agreement requires inspection
quarterly and within 24 hours of every storm greater than 1.0 inches. These
inspections will entail inspection of the perimeter of the sand filter. If it is
determined that failure of the side slopes has occurred and continue to occur over
a period of time, additional measures will be taken to strengthen the side slopes.
Lastly, based on the soils present at the site and personal observation, near
vertical walls can be constructed (or excavated) in these soils. In worst
conditions, the angle of repose is 1:1 or 45 degrees. There is no question in my
mind, that if properly constructed and compacted, the soils and slopes can be
constructed with 1:1 slopes.
Please let us know of additional submittal requirements or if you have any questions
Sincerely,
WADE TRIM, INC.
J. Chris <4arles
ssociate
cjc
CDW2009-OIE
wteim:projectwiw\Documents\Land Development\Projects\Cdw2009\Ole\Docs\Storm WaterTot 2\Submittal Cover 2008-11-14.doc
Enclosures
cc: Mr. David Scarnati, Cedarwood Development, Inc.
IN WADETium
WORK SHEET
-)? ?e4
are&--
-
P66,,e ? Lam;
-35 314
3
EV a.0, 0,96 7-
4-
t4v` k' xk7v x4
12v 6 75-
?
t, l ? rI
uj(v = )117e 6ff
W ?v .,'dJ . . 0,-76-. A 7q,5,#.:- ?9 e-)1?4
??6dllrv-ck?l- dveL,--,
45 ;zv6, ev - .4- - ?
a
)qo

1-izJoo-C A-3
SUBJECT Z BY CHK. SME NO /pgt?MBER
DATE DATE ..OF._ G 0
Form 2&1092
?IV 4,
b?
? ?k
? WADETium
WORK SHEET

Z) -7q 6IC-1

k;
?y
h?
64T
36,
a 7qg , 1,5-
V19 7
, VSZ .6.
, hd -5w, ,
/a-5v JA
--
/D,. 45-
SUBJECT (f3
BY CHK. SHEET / Jp8 NUMBER
DATE DATE • •
Form 25.1092
iN WADETium
WORK SHEET
dc V-i- X'd 175
Ste 4s7-/q 633
(?' j?(.?. i Tl k.l? l?U-?-'° ? 5 T? ? C74,y. 2 ?• 7r7 / t^
t ?J
d-er 4h 04
hzj (qt4
dym :?--
II/C
j 5oQ ?? U ts?(?. J --
1 U S i A G (o yL - c• vo - o d l,-s cc
Jlnd aU-UTV,
?15t?we
3
2?98 ?-?- liar- l ,?• ?? Obi
2
SUBJECT BY CHK. SHE 0. JOB NUMBER
-k--l DATE DATE OF • •
Forth 25-1 M
iN WADETium
WORK SHEET
3
C9. 005 Pipe
4' p t f l u, (o pr-op (YA
IcA d<fs? r-
C(,(c I
7? 6-?5 ?4?Z c?s, 9 OcA
.,s
> IOU
E??l zA ?©l
t7 2,0 163
215 A Z Z
4-5 "l I 1 ?-T

w Q = 2.1716 1 0..20 = ?I0 C-f f
591 %? SG6 44 " o K
I SUBJECT .!7 -s "4 DATE OATE - 1 SHE O. / JOB NUMBER • •
Form 25.1092
? WADETRim
WORK SHEET

54.
2? 55 .o? ?,; ? gc? ?
2.754 (22`3
r .,
4Q(t?o3Oove-, Aeocl t ?G?a
2?5L450 33 ( 179
2 429
7 c r? 02 7 ?? 6 (2--2, r ©2 + ? 2?q SS' c l--
0

?It e-5
SUBJECT BY CHK. SHE?ET JOB NUMBER
DATE DATE OF
__Y?- • •
:orm 25-1092
IN WADETRim
WORK SHEET
-? 0,he6ji, g it P;lp 617
J-0 [J C
??l
.- I ij I v
T
Q O,go a a.35
Q,2? r
(v •p °n
lam.
6 OA?
jto• G?2?boc1 ?
-D1D
6. .0 M-5
Gb ©.q o
A

Nvc-

?? ?Glti ?jliG

h d???!
5 b.00214?3
„
-D?o ' -?. 2.2. 01 C)K1

SUBJECT jyl BY CHK. SHE NO. JOB NUMBER
DATE DATE OF
Forth 251092
DA2
Roof and Loading Dock,
Drainage Area 2
SF
Sand Filter
44Reach on Link
t
Best Buy Sand Filter Drainage Area 2 Type 11 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Subcatchment DA2: Roof and Loading Dock, Drainage Area 2
Hydrograph
10 s.a7 crs
--- Type It 24-hr 1
QOr
Rainfall---74f"- - -
6 RUno Area=$53344-
Runoff :Volume=21,24
- - -9 ?f --
Runoff Depth-7:22''
6 l -!
0
5- Flow Length=293'
U.
4 Tc-3!0 min
3 N98
2
-- - -- ------- -
¦ Runoff
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
Best Buy Sand Filter Drainage Area 2 Type// 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Subcatchment DA2: Roof and Loading Dock, Drainage Area 2
Runoff = 9.47 cfs @ 11.93 hrs, Volume= 21,249 cf, Depth= 7.22"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Type II 24-hr 100yr Rainfall=7.46"
Area (sf) CN Description
30,399 98 Paved parking & roofs
4,915 98 Paved parking & roofs
35,314 98 Weighted Average
35,314 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft ) (ft/sec) (cfs)
2.3 160 0.0100 1.16 Sheet Flow, Roof
Smooth surfaces n=0.011 P2=3.28"
0.7 133 0.0050 3.21 2.52 Circular Channel (pipe), Storm
Diam= 12.0" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.013 Corruaated PE, smooth interior
3.0 293 Total
Best Buy Sand Filter Drainage Area 2 Type 1124-hr 1 yr Rainfall=3.00"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Pond SF: Sand Filter
Hydrograph
Inflow :A: sf
4 Pei - El
ev?2 5'.7 02
;Storage=4,7157 d
3-
2-
LL _ -- ------ -
¦ Inflow
? Outflow
¦ Primary
¦ Secondary
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
Best Buy Sand Filter Drainage Area 2 Type// 24-hr 1yr Rainfall=3.00"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Pond SF: Sand Filter
Inflow Area = 35,314 sf,100.00% Impervious, Inflow Depth = 2.77" for lyr event
Inflow = 3.77 cfs @ 11.93 hrs, Volume= 8,147 cf
Outflow = 0.14 cfs @ 13.24 hrs, Volume= 8,147 cf, Atten= 96%, Lag= 78.4 min
Primary = 0.07 cfs @ 13.24 hrs, Volume= 7,918 cf
Secondary = 0.06 cfs @ 13.24 hrs, Volume= 228 cf
Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Peak Elev= 2,757.02'@ 13.24 hrs Surf.Area= 1,773 sf Storage= 4,757 cf
Plug-Flow detention time= 659.8 min calculated for 8,145 cf (100% of inflow)
Center-of-Mass det. time= 659.9 min ( 1,411.1 - 751.1 )
Volume Invert Avail.Storage Storage Description
#1 2,753.50' 5,643 cf Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)
2,753.50 942 215.0 0 0 942
2,754.50 1,175 226.0 1,056 1,056 1,387
2,755.00 1,271 224.0 611 1,668 1,520
2,755.50 1,418 237.0 672 2,340 2,011
2,756.50 1,652 242.0 1,534 3,873 2,317
2,757.00 1,769 245.0 855 4,728 2,485
2,757.50 1,889 248.0 914 5,643 2,655
Device Routing Invert Outlet Devices
#1 Primary 2,753.50' 1.750 in/hr Exfiltration over Horizontal area
#2 Secondary 2,752.35' 15.0" x 42.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,751.45' S= 0.0214'/' Cc= 0.900
n= 0.013 Corrugated PE, smooth interior
#3 Device 2 2,757.00' 8.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
Primary OutFlow Max=0.07 cfs @ 13.24 hrs HW=2,757.02' (Free Discharge)
t-1=Exfiltration (Exfiltration Controls 0.07 cfs)
econdary OutFlow Max=0.06 cfs @ 13.24 hrs HW=2,757.02' (Free Discharge)
Culvert (Passes 0.06 cfs of 11.88 cfs potential flow)
3=Sharp-Crested Rectangular Weir (Weir Controls 0.06 cfs @ 0.42 fps)
Best Buy Sand Filter Drainage Area 2 Type 11 24-hr 10yr Rainfall=5.07"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Pond SF: Sand Filter
3
0
LL
Hydrograph
[6.12d$
Area=35;344-sf---
5.97 ds
e E'lev 2 57.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
5.5
'Storage=5,375 d
1
¦ Inflow
? Outflow
¦ Primary
¦ Secondary
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
Best Buy Sand Filter Drainage Area 2 Type 11 24-hr 10yr Rainfal1=507"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 0 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Pond SF: Sand Filter
Inflow Area = 35,314 sf,100.00% Impervious, Inflow Depth = 4.83" for 10yr event
Inflow = 6.42 cfs @ 11.93 hrs, Volume= 14,223 cf
Outflow = 5.97 cfs @ 11.96 hrs, Volume= 14,223 cf, Atten= 7%, Lag= 1.3 min
Primary = 0.08 cfs @ 11.96 hrs, Volume= 8,990 cf
Secondary = 5.89 cfs @ 11.96 hrs, Volume= 5,232 cf
Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Peak Elev= 2,757.36'@ 11.96 hrs Surf.Area= 1,854 sf Storage= 5,375 cf
Plug-Flow detention time= 450.3 min calculated for 14,223 cf (100% of inflow)
Center-of-Mass det. time= 450.3 min ( 1,191.2 - 740.9 )
Volume Invert Avail.Storage Storage Description
#1 2,753.50' 5,643 cf Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)
2,753.50 942 215.0 0 0 942
2,754.50 1,175 226.0 1,056 1,056 1,387
2,755.00 1,271 224.0 611 1,668 1,520
2,755.50 1,418 237.0 672 2,340 2,011
2,756.50 1,652 242.0 1,534 3,873 2,317
2,757.00 1,769 245.0 855 4,728 2,485
2,757.50 1,889 248.0 914 5,643 2,655
Device Routing Invert Outlet Devices
#1 Primary 2,753.50' 1.750 in/hr Exfiltration over Horizontal area
#2 Secondary 2,752.35' 15.0" x 42.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,751.45' S= 0.02147' Cc= 0.900
n= 0.013 Corrugated PE, smooth interior
#3 Device 2 2,757.00' 8.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
Primary OutFlow Max=0.08 cfs @ 11.96 hrs HW=2,757.36' (Free Discharge)
L1=Exfiltration (Exfiltration Controls 0.08 cfs)
econdary OutFlow Max=5.87 cfs @ 11.96 hrs HW=2,757.36' (Free Discharge)
Culvert (Passes 5.87 cfs of 12.37 cfs potential flow)
3=Sharp-Crested Rectangular Weir (Weir Controls 5.87 cfs @ 1.95 fps)
Best Buy Sand Filter Drainage Area 2 Type 11 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Pond SF: Sand Filter
Hydrograph
2.47 ds
9.Cr, Inflow';Area=35,3'''14 sf
10
9.;a??8 Peak E1eV?2,7$7- g'
9 -"
Storage'=5-,60
cf
- -- ---- -------
8
7- 7
H 6 ,
U. 5
4 -- -- -
3 -- - - -
2
1 "
¦ Inflow
? Outflow
¦ Primary
¦ Secondary
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48
Time (hours)
Best Buy Sand Filter Drainage Area 2 Type 11 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 0 2007 HvdroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Pond SF: Sand Filter
Inflow Area = 35,314 sf,100.00% Impervious, Inflow Depth = 7.22" for 100yr event
Inflow = 9.47 cfs @ 11.93 hrs, Volume= 21,249 cf
Outflow = 9.17 cfs @ 11.95 hrs, Volume= 21,235 cf, Atten= 3%, Lag= 0.9 min
Primary = 0.08 cfs @ 11.95 hrs, Volume= 9,622 cf
Secondary = 9.10 cfs @ 11.95 hrs, Volume= 11,613 cf
Routing by Stor-Ind method, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs
Peak Elev= 2,757.48'@ 11.95 hrs Surf.Area= 1,884 sf Storage= 5,602 cf
Plug-Flow detention time= 336.9 min calculated for 21,231 cf (100% of inflow)
Center-of-Mass det. time= 336.7 min ( 1,071.8 - 735.1 )
Volume Invert Avail.Storage Storage Description
#1 2,753.50' 5,643 cf Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)
2,753.50 942 215.0 0 0 942
2,754.50 1,175 226.0 1,056 1,056 1,387
2,755.00 1,271 224.0 611 1,668 1,520
2,755.50 1,418 237.0 672 2,340 2,011
2,756.50 1,652 242.0 1,534 3,873 2,317
2,757.00 1,769 245.0 855 4,728 2,485
2,757.50 1,889 248.0 914 5,643 2,655
Device Routing Invert Outlet Devices
#1 Primary 2,753.50' 1.750 in/hr Exfiltration over Horizontal area
#2 Secondary 2,752.35' 15.0" x 42.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,751.45' S= 0.0214'/' Cc= 0.900
n= 0.013 Corrugated PE, smooth interior
#3 Device 2 2,757.00' 8.5' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
Primary OutFlow Max=0.08 cfs @ 11.95 hrs HW=2,757.48' (Free Discharge)
L1=Exfiltration (Exfiltration Controls 0.08 cfs)
econdary OutFlow Max=9.08 cfs @ 11.95 hrs HW=2,757.48' (Free Discharge)
Culvert (Passes 9.08 cfs of 12.54 cfs potential flow)
3=Sharp-Crested Rectangular Weir (Weir Controls 9.08 cfs @ 2.26 fps)
Permit NuinWr:
(to be provided bj,1)WQ)
Drainage Arco Number:
Sand Filter Operation and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity of
structures, safety of the public, anti the removal efficiency of tile BMP.
Important maintenance procedures:
- The drainage area will be carefully managed to reduce the sediment load to the
sand filter.
- Once a year, sand media will be skimmed.
- The sand filter media will be replaced whenever it fails to function properly after
vacununmg.
The sand filter will be inspected quarterly and within 24 hours after every storm event
greater than 1.0 inches (or 1.5 inches if in a Coastal County). Records of operation and
maintenance will be kept in a known set location and will be available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall be
repaired inunediately.
LIMP element: Potential problem: How I will remediate the problem:
The entire BMP Trash/debris is resent. Remove the trash/debris.
The adjacent pavement Sediment is present on the Sweep or vacuum the sediment as
(if applicable) pavement surface. soon as possible.
The perimeter of the Areas of bare soil and/or Regrade the soil if necessary to
sand filter erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Vegetation is too short or too Maintain vegetation at a height of
long. a roximatel six inches.
The flow diversion Tile structure is clogged. Unclog the conveyance and dispose
structure of an sediment off-site.
The structure is damaged. Make any necessary repairs or
replace if damage is too large for
-repair.
The pretreatment area Sediment has accumulated to Search for the source of the
a depth of greater than six sediment and remedy the problem if
inches. possible. Remove the sediment and
dispose of it in a location where it
will not cause impacts to streams or
the BMP.
F-,rosion has occurred. Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
prevent future erosion problems.
Weeds are present. Remove the weeds, preferably by
hand. If a pesticide is used, wipe it
on tile1?lants rather than spraying.
Form SW40I-Sand Filter O&M-Rev.3 Pagc I of'3
BMP element: Potential problem: How I will remediate the problem:
The filter bed and Water is ponding on the Check to see if the collector system
underdrain collection surface for more than 24 is clogged and flush if necessary. If
system hours after a storm. water still ponds, remove the top
few inches of filter bed media and
replace. If water still ponds, then
consult an expert.
The outflow spillway Shrubs or trees have started Remove shrubs and trees
and pipe to row on the embankment. immediately.
The outflow pipe is clogged. Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
prevent future erosion problems.
The outflow pipe is damaged. Repair or replace the pipe.
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality 401 Oversight Unit at 919-
outlet. 733-1786.
Form SW401-Sand Filter O&M-Rev.3 Page 2 of '3
Permit Number:
(to be pi-ovided by UIVQ)
I acknowledge and agree by my signature below that 1 am responsible for the
performance ofthe maintenance procedures listed above. I agree to notify DWQ of any
problems with the system or prior to any changes to the system or responsible party.
Proiect uameMaynesville Commons - Best Buy Lot 2 __...._
BA4P cb iiuage urea uumbet-:
Print namc:David A. Scarnati
Title:Director of Development
Address: 1765 Merriman Road Akron 011 44313
Phone:[phone]
Signature:
Date:
Note: The legally responsible party should not be a homeowners association unless more than 501/o of
the lots have been sold and a resident of the subdivision has lien named the president.
_LA -St?L, , a Notary Public for the State of
?h['O County of do hereby certify that
D/R ?i y /a Se t?", -A personally appeared before me this .-I day of e U a-uor , and acknowledge the due execution of the
forgoing sand filter maintenance requirements. Witness my liand and official seal,
\\,\,\11\IIIIIII/,,,,,,
A1Al -
Julie A. Lasky
-?? Resident Summit County
* * = Notary Public, State of ON
*
`° r s My Commission Expires: 0510 20
'?, J'lATf 0 f O??o\.
'??1,1111\ I\\II\\`\\\,
SIAL - a
My commission expires 5--A// Z
Form SW401-Sand Filter 0&!vl-Rev. 3 Page 3 of'
3
u .'
Christy, Charles
From: Matthew McCurdy [[e-mail]]
Sent: Tuesday, November 11, 2008 2:31 PM
To: Christy, Charles
Cc: David Scarnati
Subject: RE: Waynesville - Best Buy
Chuck,
The slopes are steeper than typically is considered stable, but since the finished slopes are only about
2.5 to 3.5 feet tall, most areas should hold up. Some sloughing and erosion is likely in areas over time
and the need for maintenance of the slopes should be expected. Loss of soil around the wall that is only
1 foot away could cause damage, so the bottom of the wall needs to be low enough to reduce that
chance.
Matt
Matt McCurdy, PE
Project Engineer
*113"d ME
ENGINEERING INTEGRITY.
SWE, Inc.
44 Buds Shoals Road, Unit C3
Arden NC 28704 Map
Ph: 828-687-9080
Fax: [phone]
[e-mail]
www.smeinc.com
This electronic message and its attachments are forwarded to you for convenience and "for
information only." The message may represent a summary with limitations, conditions and
further explanations omitted in the interest of brevity and time constraints. The contents of this
electronic message and any attachments may be preliminary and incomplete, subject to review
and revision. If this electronic transmittal contains Findings, Conclusions or Recommendations,
S&ME, Inc. will submit a follow-up hard copy via mail or overnight delivery for your records,
and this hard copy will serve as the final record. In the event of conflict between electronic and
hard copy documents, the hard copy will govern. This electronic message and any attachments
transmitted with it are the property of S&ME, Inc. and may contain information that is
confidential or otherwise protected from disclosure. The information this electronic message
contains is intended solely for the use of the one to whom it is addressed, and any other recipient
should delete this electronic message and destroy all copies. VER 4, Rev 1 - 031207
From: Christy, Charles [mailto:[e-mail]]
Sent: Monday, November 10, 2008 3:36 PM
To: Matthew McCurdy
Cc: David Scarnati
11/14/2008
Subject: Waynesville - Best Buy
Matt,
Can you look at the sand filter detail on this sheet, lower left hand corner. we are proposing to construct
the sand filter with side slopes of 1:1. The depth to bottom of sand will range from 3.5 to 4.35 feet. The
depth from top of sand will range from 2.0 to 2.7 feet. We propose to cover the slopes with PVC and sod
stapled to the slope. NCDENR has expressed a stability concern with regards to the proposed slopes.
Can you review and determine that the slopes will be stable to construct and stable after completion. Let
me know if you have any questions. A response via email will be fine as we are trying to respond to
DENR as soon as possible.
Thanks,
Chuck
Wade Trim, Inc.
Charles J. Christy, PE, Associate
Land Development Services
Office: 828.665.1288
Cell: 828.337.0251 (24-7)
Fax: [phone]
11/14/2008
.... +
TECHNICAL NOTE
TN 1.02
Single Wall HDPE Perforation Patterns October 2008

Nominal I.D.
Perforation
Type Maximum Slot
Length or
Diameter Maximum
Slot Width Minimum Inlet
Area
Pattern
Type
in mm in mm in mm in"/ft cm-/m
3 75 Slot 0.875 22 0.120 3 1.0 21 A
4 100 Slot 0.875 22 0.120 3 1.0 21 B -
5 125 Slot 0.875 22 0.120 3 1.0 21 B
6 150 Slot 0.875 22 0.120 3 1.0 21 B
8 200 Slot 1.18 30 0.120 3 1.0 21 B -
10 250 Slot 1.18 30 0.120 3 1.0 21 B
12 300 Slot 1.50 38 0.118 3 1.5 32 B
12 300 Circular 0.313 8 - - 1.5 32 C
15 375 Circular 0.313 8 + - - 1.5 32 C
18 450 Circular 0.313 8 - - 1.5 32 C
24 600 Circular 0.313 8 - - 2.0 42 D
TYPE A PATTERN
45' 45'
2 SLOT PATTERN
PERFORATIONS
ROTATED 90' EVERY
OTHER VALLEY
8 HOLE PATTERN
TYPE B PATTERN
3 SLOT PATTERN
PERFORATIONS
ROTATED 60' EVERY
OTHER VALLEY
TYPE D PATTERN
6 HOLE PATTERN

2
I 4640 TRUEMAN BLVD. HILLIARD, OH 43026 [phone] www.a"pe.com 1
ATN102 ®ADS 2008
Techn i0
ca
W
NotesTechnical Note 2.105
Re: Outflow from Perforated Pipe
Date: January 2004 (Published May, 2004)
Introduction
In order to provide guidance to the engineering community in designing drainage or recharge
systems, ADS has conducted theoretical computations using an orifice equation. It should be
emphasized that ADS conducted these calculations using ADS standard perforation patterns, and
that the values are based on free outlet (no backfill) through the perforations. Infiltration is
assumed to be equal to the calculated exfiltration rate.
When designing storm water drainage or recharge systems, the goal in mind is to calculate the
amount of storm water which can escape the pipe and replenish the ground water. Although
some may believe that the controlling parameter is the free outflow from the perforated pipe, this
is not often the case. A perforated pipe can only discharge water at a rate at which the surround-
ing soil will accept it.
Procedure
The goal is to calculate the free outflow from the perforations in a pipe. Knowing the perforation
hole diameter and hole pattern, a simple orifice equation can be used to calculate the flow rate in
cubic feet per second.
Orifice equation
QP = CdA 2gH
Where
QP = free out fall flow rate through one perforation (ft3/sec)
Cd = Coefficient of discharge = 0.60
A = Cross sectional area of one perforation (fe)
g = Gravimetric constant = 32.2 ft/secz
H = Height of water above perforation, head (ft)
Having the orifice equation, the location of the perforations with respect to the invert of the pipe
and the size of perforations, the free outflow at any elevation in the pipe can be calculated. To
calculate the amount of flow per foot of pipe, or unit length, simply multiply the free outflow in
one valley by the number of valleys per foot of pipe.
With the above procedure, we can calculate the free outflow at any given elevation provided the
perforation orientation is known. Looking at a typical curve inside a pipe cross section, (Chart 1.)
the curve is somewhat jumpy and not uniform throughout the pipe cross section. As the water
head increases, however, the curve becomes more uniform and looks much more like a curve
produced from using the orifice equation, Chart 2. The non-uniform part of the curve is due to
the additional perforations holes at higher elevations inside the pipe cross-section, producing
what can be characterized as hydraulic jumps.
4840 TRUEMAN BLVD. HILLIARD, OH 43026 [phone] http://www.ad"ipe.com
When designing a pipe in typical storm sewer design, the pipe is assumed to be flowing full. For
the purposes of this technical note, charts have been provided showing the relationship between
free outflow and water head elevation when the pipe is full. Placed on these charts is a second
order polynomial which best describes the data. This polynomial may be used to estimate the
free outfall at various head elevations.
The designer should keep in mind that, for some applications and some pipe sizes, the free outfall
from the pipe perforations may be larger than the flow rate of the pipe itself and thus the pipe
may not flow full. This, however, will only exist in applications where the water is purely in a
free outflow state and is not inhibited by the surrounding soil.
The determining factor for recharge systems is the surrounding soil's ability to accept water, not
the pipe's ability to deliver water. Although the perforations in the pipe determine the allowable
area at which water can be released, it is the soil's ability to accept the water that is the
determining factor in designing recharge systems. This can best be described with the following
example:
Example
A 12" diameter drainage pipe is used to recharge the ground water table through very permeable
backfill envelope (coefficient of permeability, K = 1,000 m/d = 0.0375 ft/s). The ground water
table is 3 feet below the pipe. The 12" diameter pipe has a total of 36 - 0.375" diameter holes per
foot of pipe (area at which water enters the backfill envelop, A = 0.0276 ftz/foot of pipe).
Assume the pipe is full; determine the outfall rate of storm water through the pipe alone, (no
backfill) and the acceptance rate of the soil envelope.
A) The outfall rate of the 12" pipe has been determined using the aforementioned procedure
for determining the free outflow of a perforated pipe. Q pir, fr, = 0.086 ft;/s/ft = 38.7
gpm./foot of pipe.
TOP OF GRADE
PIPE
`-SURROUNDIN
WITH PERNE
FT
L = 3 FT
GROUND WATER TABLE
Figure 1.
B).Using Darcy's Law one can solve for the flow through the soil.
% = KiA
Where, Q = Flow rate through soil, ft'/s
K = The permeability of the soil = 0.0375 ft/s
i = Hydraulic gradient (AH/L), ft/ft
A = Area (sum of the areas from the perforations) = 0.0276 fe
% = 0.0375 ft x 3 ft x 0.0276 ft' = 0.0014 ft per foot of soil along the pipe
Or
Qs = 0.63 gallons per foot of soil along the pipe, Q, << Qp
min.
As the example shows, the flow rate through the soil is much less than the flow rate through the
pipe perforations. Although the area at which water can reach the soil is determined by the pipe
perforations, the surrounding soil determines the flow rate through the soil. When designing
drainage or recharge systems, one should reference the minimum inlet areas listed in ADS
Product Note 3.106, AASHTO M294, or contact the pipe manufacturer for a detailed explanation
of its pipe's perforation pattern.
OUTFLOW - ADS PIPE
PIPE NOT FULL
120-
100-
P 80-
60--
3
0
u. 40
u.
20
0
0
2 4 6 8 10 12 14 16 18 20 22
HEAD (INCHES)
Chart 1.
ORIFICE EQUATION
14-
12-
10-
U)
V_ 8
O g
4--
2
0
0 5 10 15 20 25 30
HEAD (FEET)
Chart 2.
3
I
i
3
f
i
t#
R
I
1 +
(+i
rn
i co
ri
1 +
X
co
N
O
4 O
S
II
T !
s
t
d
s
r
1
r
s
6
qi
f
U
CO
? N
a to
U A
N U
N v
U T o
? 'v a
i
r
S
Cam'
i
r cc
a
N
we
(. zQ
a
U) CL
C)
_
awJ
CL U.
J
-j = ?
LL
LL U) Oa
V
'Cr
co (O et tV O CQ tp v N
r r r .-r
S UJIMS) MOIJ

m
LO
IT
(n
N
LO
0
O
co
'd'
co
N ,
O
rk
r?
co
M
(D
Cl)
v
co
N
Cl)
M W
x
co z
N
O
co
N x
v
N
N
N
O
N
Go
I
r
O
O
co
It
N
O
/I
(f ?.
t
G"
C
Aw
~ W
a
U)
Q?
Q W OJ
IL LL.
J
0 =
LL
? Q
o?
co
N
O
N
M
x
CA
Co
x
co
to
N
O
O
T

a a
c U
N
U ?
N U

m
iD CL
I
. d

O 000 C D O V O N O c o t 0 D N a C)
N r r r r
(.U/WdD) MO-14
O
tD
00
to
CD
to
N
LO
O
U)
co
Q
CD
v
v
N
O
d'
OD
M
CD
M
co
co
N N
M w
x
o z
M
N =
to
N
N
N
N
0
N
O
CD
N
r
O
r
co
CD
N
O
O
c?
s:"C
.
.r

l

W o
r=? a z
as
Nay
t/1
O
uj -j
a IL
LL
J
J
0 = m
U.
OV
CO
I

tsi
N

x
CD
M
O
Ch
t
x
fl-
M
N
O
O
11
s
n
a
3
I

0
0- D-
CO U
i c N
U ? I
1 N U '
y
f0
f U 1 i
0
co 0_
I ?
` G

?
R to
O 0 0 0 co OIt N C) Q O 000 CO O
D V N
N - r r - r
CUIMO) MO-1 A
O
CD
co
M
co
to
N
O
LO
co
cD
v
N
Cl
IT
00
M
co
N N
M ui
x
U
O z
M ;r
00
N W
CD
N
N
N
N
O
N
00
co
,It
r
N
O
co
- cD
N
O
O

N'WADETRim
WORK SHEET
1.2tl lei
Drd-j'tjaj,,.,- Orewl-,
a ss
73 ;f} ?t?A4 oe4? ? (-6-ffvlc , U4

pv 14b U 117' NOV 1 7 2008
GENR ',NA:TFR WATER BR
WETLANDS AND oTt*M

tt'lvv "j
ti
L# 2 c?
1 I+l` v

27? 1. Sb - z7577
hmtt N

'2 1?
Z
4 z- "315-Std" , 51 C/,
3z-e- Ajc4-e c,,d r r6-4
Af = j Z -;a 360
4s ,e4 _ `7`f9
// nr • CHK SHEETNO. MNUMBER
-= DATE (? / 7i bk DATE OF Caw • 2LtD f •V r {_
Form 25.1082
IN'WADETium
WORK SHEET
' J
h,LS Ike
Vol io P&AJ 1770.2q_ ( p?yrtx pwl e-le-v) t&
z? 1?dt/'Cad (trrt bn f"J Vol i
P
<L>A.+2..J - Lom. 5 ? v o-o (? ? l
Z1?t A
Z ?66.,z5
_D?-(('
q
Re?' d
L4 A
Vul Q
1? ojJ',-'G-d ve-rA
-Z,Q1 '> G4 W ('T V ` "1 ,G16 r Z60/0 +?-' / (1, lee O K'
0
aunxL i I BY cw. SHEET NO. JOB NU BER
J DATE I J13 In - DATE OF _ 700 % ' O[ c"',
-am 25.1092 - 1? - -
N'WADETium
WORK SHEET
?ejfav_ot (/)(kslvt 0,,ec4_, /:,
1
V?
AV ?t,
-3043 ff 2.
415 PGY' f 4"Cc' C1 (? ?? U U 5 ?T s- a ?j ? I
L? +
5&j F%, 14? &4 ?U? 4te_ A lecl, s
IN4
y
2 • 2.0
v
2?•5J
A? :?: 4,1 i ?ff ,
?
Prov,14 ' o x 4-2 0 s4 fI?+d??.
SUBJECT BY CHK. SHEET NO. JOB NUMBER
5 DATE 1 3 DATE of ?bw • Zp0 -ole
Form 25-1092
[N* WADETRim
WORK SHEET
? si -Ft
5
???/? j ? h? o I w?, LVI ,
4ok k4wiitx w s-c,
O,bif S
0.4
0005 0.
S' Cave.
IcIr
? ?c?o Gad -(?
& "Dl '!?T-Pf OuToa 'Pi peg ,
SUBJECT
SWET
6/5? Bull FDATE
( roe ' DATE DF Zoeq -
Form 2sw 9- 7 U) O
Permit Number.
(to be provided by DWQ)
n
AC*,
WWNR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
SAND FILTER SUPPLEMENT
This form must be filled out on line, printed and submitted with all of the required information.
Make sure to also fill out and submit the Required Items Checklist (Section 1I1) and the I&M Agreement (Section IV)
oa?? wAr?q°?
r
P Y
I. PROJECT INFORMATION
Project name Waynesville Commons - Best Buy, Lot 2
Contact name Charles J. Christy
Phone number 828-337-0251
Date
Drainage area number
November 13, 2008
Parking Lot, Drainage Area 1
II. DESIGN INFORMATION
Site Characteristics
Drainage area (AD)
Impervious area
% Impervious (IA)
Design rainfall depth (RD)
Peak Flow Calculations
1-yr, 24-hr runoff depth
1-yr, 24-hr intensity
Pre-development 1-yr, 24-hr runoff
Post-development 1-yr, 24-hr runoff
Pre/Post 1-yr, 24-hr peak control
Storage Volume
Design volume (WQV)
Adjusted water quality volume (WQVW?
Volume contained in the sedimentation basin and on top of the sand filter
Maximum head on the sedimentation basin and sand filter (hM F,I,)
Average head on the sedimentation basin and sand filter (hA)
Runoff Coefficient (Rv)
Type of Sand Filter
Open sand filter?
If this is an open sand filter: The clearance between the bottom of the sand
filter and the SHWT (dww)
Closed/pre-cast sand filter?
If this is a dosed sand filter: The clearance between the bottom of the sand
filter and the SHWT (dam)
If this is a dosed, underground closed sand filter: The clearance between
the surface of the sand filter and the bottom of the roof of the underground
structure (dam,)
60,814.00 ft2 OK
57,530.00 ft2
94.6%%
1.00 in
in
in/hr
Wises
fe/sec
fe/sec
4,625.00 ft'
3,468.75 ft' OK
15,030.00
3.75 ft OK
1.88 ft OK
0.90 (unitless)
N Yor N
Y Yor N
1.00 ft
Form SW401-Sand Filter-Rev, 3 Parts I and 11. Project Design Summary, Page 1 of 3

Permit Number:
(to be provided by DWQ)
Sedimentation Basin
Surface area of sedimentation basin (As)
OK. Meets minimum, but may need to be increased to
3,588.00 fe contain the required volume if error under Storage
Volume section.
Sand Filter
Surface area of sand filter (AF)
Depth of the sand media filter bed (dF)
Coefficient of permeability for the sand filter (k)
Time to drain the sand filter (t)
Time to drain the sand filter (t)
Additional Information
Does volume in excess of the design volume bypass the sand filter?
Is an off-line flow-splitting device used?
Does volume in excess of the design volume Clow evenly distributed through a
vegetated filter?
What is the length of the vegetated filter?
Does the design use a level spreader to evenly distribute flow?
Is the BMP located at least 30ft from surface waters (50ft if SA waters)?
Is the BMP located at least 100ft from water supply wells?
Are the vegetated side slopes equal to or less than 3:1
Is the BMP located in a recorded drainage easement with a recorded access
easement to a public Right of Way (ROW)?
What is the width of the sedimentation chamberlforebay (Wsw)?
What is the depth of sand over the outlet pipe?
OK. Meets minimum, but may need to be increased to
420.00 ft' contain the required volume 4 error under Storage
Volume section.
2.00 ft
3.50 (It/day)
40.00 hours OK. Submit drainage calculations.
1.67 days
Y YorN OK
Y Y or N OK
N Y or N Excess volume must pass through filter.
It
Yor N
Y Yor N OK
Y Y or N OK
Y Y or N OK
Y Y or N OK
30.00 it OK
1.67 it OK
Figure 1: Open Sand Filter
SedlUkCadaholt S:arJ Fdtei
C'tnwber '6+6rr
1 or For ebax.
r «''u
Flow rotlet khl.e
1_`ff I:'tt
}
Tu-Sdu Sort a Seagouabh? Iirsh Witter Table
.................................
w_.,
iIP'P' iiF
;W ....... ...
' 6Hwr
Form SW401-Sand Filter-Rev-3 Parts I and It. Project Design Summary, Page 2 of 3

Wen
\.\
Floc
"Welland \
1'onitetc for other
4hnchual tuatcuall
hi-Situ Soil/
Seasonably Hi0i
Watct Table
Watel
Collected
Figure 2: Closed Sand Filter
llti Covet r3t.dc.?
\ 4-hillct Pipe
pace
................ ..........t
:tlPipe
\ .................. : 1js
F
i+ 46wr
tiedunet?tatton OItantbet rF:6cbavr i Sand Ftltet r'9tmubcr
rHc•?vy yedm?mts, ('TrappcA aohds?
:............:
'1 SuJ
Permit Number:
(to be provided by DWO)
Form SW401-Sand Fitter-Rev.3 Parts 1 and II. Project Design Summery, Page 3 of 3
Permit No.
(to be provided by DWQ)
III. REQUIRED ITEMS CHECKLIST
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal
package will result in a request for additional information. This will delay final review and approval of the project. Initial
in the space provided to indicate the following design requirements have been met. If the applicant has designated an agent, the
agent may initial below. If a requirement has not been met, attach justification.
Initials Pagel Plan
Sheet No.
1. Plans (1" - 5(Y or larger) of the entire site with labeled drainage area boundaries li - 7'0
- System dimensions (length, width, and depth) for both the sedimentation chamber and the filter
chamber C - Z t
- Maintenance access, C '
- Flow splitting device,
- Proposed drainage easement and public right of way (ROW), ?? - j.0
- Design at ultimate build-out, C - I.0
- Off-site drainage (if applicable), and WA
- Boundaries of drainage easement. C - 2112-
L? 2. Plan details (1" = 50' or larger) for the sand filter showing:
- System dimensions (length, width, and depth) for both the sedimentation chamber and the filter
chamber e .. Z.I
- Maintenance access, 1.0
- Flow splitting device, - 2.1
- Proposed drainage easement and public right of way (ROW), C-1,0
- Design at ultimate build-out, C - j.0
- Off-site drainage (if applicable), and GJ,4
- Boundaries of drainage easement. C - `2 - Z
"
'
3. Section view of the sand filter 0
= 20
or larger) showing:
- Depth(s) of the sedimentation chamber and sand filter chamber, C -,2
.
- Depth of sand filter media C, 2,i'
- Connection between the sedimentation chamber and the sand filter chamber,
- SHWT level(s) C - 2 . j
- Outlet pipe, and C - 2. t t C-
- Clearance from the surface of the sand filter to the bottom of the roof of the underground structure (if
applicable) F. (, ?,?b 2. So foal 9,c-f ?Z760. Z4 ((-if)
4. A soils report that is based upon an actual field investigation, soil borings, and infiltration tests. The
results of the soils report must be verified in the field by DWO, by completing & submitting the soils
investigation request form. County soil maps are not an acceptable source of soils informatior .
c?Z. t
?? t it t1J4 r 12o ,N?? Nw i , ,?7n,c? r? c.
xd
L (rs 5. Supporting calculations (including drainage calculations)
6. Signed and notarized operation and maintenance (O&M) agreement %r2 iH Cbrtit,-^9
(t ?! 7. A copy of the deed restrictions (if required). e';; &) S (
0eA-
?
Form SW401-Sand Finer-Rev.3 Part III, Page 1 of 1
DA1
on
Parking Lot, Drainage
Area 1
Pond
Su4 Reach on Link
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 1yr Rainfall=3.00"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD®8 50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Subcatchment DA1: Parking Lot, Drainage Area 1
7
Hydrograph

6- --
5-
4-

0
-- --
LL 3
2

1 -------- -------- --
24'; hip--'lyr
Type-It
Rainfall=3.00
Ranof f ??r6al= 0:8,f 4 S.
Runoff o ume
Runoff popth;_-2.65','
Flow--Length=359'
T&2.4 rain
¦ Runoff
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60
Time (hours)
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 1 yr Rainfall=3.00"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Subcatchment DA1: Parking Lot, Drainage Area 1
Runoff = 6.41 cfs @ 11.93 hrs, Volume= 12,934 cf, Depth= 2.55"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs
Type II 24-hr lyr Rainfall=3.00"
Area (sf) CN Description
57,530 98 Paved parking & roofs
3,284 61 >75% Grass cover, Good, HSG B
60,814 96 Weighted Average
3,284 Pervious Area
57,530 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
1.0 80 0.0180 1.28 Sheet Flow, Parking Lot
Smooth surfaces n= 0.011 P2= 3.28"
0.3 72 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.0 9 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.5 120 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.2 42 0.0025 3.42 4.20 Circular Channel (pipe), Pipe
Diam= 15.00" Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.010 PVC, smooth interior
0.0 14 0.0025 4.68 14.70 Circular Channel (pipe), Pipe
Diam= 24.00" Area= 3.1 sf Perim= 6.3' r= 0.50'
n= 0.010 PVC, smooth interior
0.4 22 0.0001 0.94 2.94 Circular Channel (pipe), Pipe
Diam= 24.00" Area= 3.1 sf Perim= 6.3' r= 0.50'
n= 0.010 PVC. smooth interior
2.4 359 Total
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type 1124-hr 10yr Rainfal1=5.07"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Subcatchment DA1: Parking Lot, Drainage Area 1
Hydrograph
12
2ds
i
Ty 4-hr''10yr
,o Rainfall''= w.a7"
_
9 - -Runoff Ara=0' 814'' sf
---------------------- -- - - ------------- - - ---
8-
Runoff _ Volume
=1 233; cf __
--
Zo o1r
':Runoff b_pth' 4.G
il: 6 ---- ---' F1ow_ Length=359,'
5 Tc--2.4± min
-
4 CN099--
3
2
- - - - - - - - - - - - - - - - - -- - - - --- - - -
---- --- -------- --------
---- ---- ----- -- ---- -------- ------------- ---
¦ Runoff
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60
Time (hours)
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type 11 24-hr 10yr Rainfall=5.07"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Subcatchment DA1: Parking Lot, Drainage Area 1
Runoff = 11.12 cfs @ 11.93 hrs, Volume= 23,323 cf, Depth= 4.60"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs
Type II 24-hr 10yr Rainfall=5.07"
Area (sf) CN Description
57,530 98 Paved parking & roofs
3,284 61 >75% Grass cover, Good, HSG B
60,814 96 Weighted Average
3,284 Pervious Area
57,530 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
1.0 80 0.0180 1.28 Sheet Flow, Parking Lot
Smooth surfaces n=0.011 P2=3.28"
0.3 72 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.0 9 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.5 120 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.2 42 0.0025 3.42 4.20 Circular Channel (pipe), Pipe
Diam= 15.00" Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.010 PVC, smooth interior
0.0 14 0.0025 4.68 14.70 Circular Channel (pipe), Pipe
Diam= 24.00" Area= 3.1 sf Perim= 6.3' r= 0.50'
n= 0.010 PVC, smooth interior
0.4 22 0.0001 0.94 2.94 Circular Channel (pipe), Pipe
Diam= 24.00" Area= 3.1 sf Perim= 6.3' r= 0.50'
n= 0.010 PVC, smooth interior
2.4 359 Total
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Subcatchment DA1: Parking Lot, Drainage Area 1
Hydrograph
18
------- - -----
17 78.52 cfa
16 -- - - fip Il4-hr 1OOYt?--
'Rain
14? 0814
f /fir f
6 s
,3 R n
unoff
r?fo
Iume=X5;385' cf
_ 11
- --------------------------- --
Ru6off DopthF$_98'
0 9 -
ow Len?g#h=35 '
LL $ F
7
Tc_ 2 4- ruin
g
- ------ -----
C
- - - - - - - - - - - - - -
4
3 --
2
------------ -- ---- --------- -------- --------- --------
¦ Runoff
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60
Time (hours)
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type 11 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Subcatchment DA1: Parking Lot, Drainage Area 1
Runoff = 16.52 cfs @ 11.93 hrs, Volume= 35,385 cf, Depth= 6.98"
Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs
Type II 24-hr 100yr Rainfall=7.46"
Area (sf) CN Description
57,530 98 Paved parking & roofs
3,284 61 >75% Grass cover, Good, HSG B
60,814 96 Weighted Average
3,284 Pervious Area
57,530 Impervious Area
Tc Length Slope Velocity Capacity Description
(min) (feet) (ft/ft) (ft/sec) (cfs)
1.0 80 0.0180 1.28 Sheet Flow, Parking Lot
Smooth surfaces n=0.011 P2=3.28"
0.3 72 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.0 9 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.5 120 0.0050 4.17 3.28 Circular Channel (pipe), Pipe
Diam= 12.00" Area= 0.8 sf Perim= 3.1' r= 0.25'
n= 0.010 PVC, smooth interior
0.2 42 0.0025 3.42 4.20 Circular Channel (pipe), Pipe
Diam= 15.00" Area= 1.2 sf Perim= 3.9' r= 0.31'
n= 0.010 PVC, smooth interior
0.0 14 0.0025 4.68 14.70 Circular Channel (pipe), Pipe
Diam= 24.00" Area= 3.1 sf Perim= 6.3' r= 0.50'
n= 0.010 PVC, smooth interior
0.4 22 0.0001 0.94 2.94 Circular Channel (pipe), Pipe
Diam= 24.00" Area= 3.1 sf Perim= 63 r= 0.50'
n= 0.010 PVC. smooth interior
2.4 359 Total
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 1 yr Rainfall=3.00"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Pond Pond: Pond
Hydrograph
6.41 ds
--- - -- -- ,' - -A-'rea=6Q $ -
, -' 'In'flo??rr't'? '??
-'PO 2,x$_1',.301---
6 ,Storage:=12,70'0 d
5
----, - - - --
4
VL 3-
------------ ------- - -------
2
¦ Inflow
? Outflow
¦ Primary
¦ Secondary
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60
Time (hours)
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 1 yr Rainfall=3.00"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 02007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Pond Pond: Pond
Inflow Area = 60,814 sf, 94.60% Impervious, Inflow Depth = 2.55" for 1yr event
Inflow = 6.41 cfs @ 11.93 hrs, Volume= 12,934 cf
Outflow = 0.01 cfs @ 24.05 hrs, Volume= 1,061 cf, Atten= 100°/x, Lag= 727.7 min
Primary = 0.01 cfs @ 24.05 hrs, Volume= 1,061 cf
Secondary = 0.00 cfs @ 0.00 hrs, Volume= 0 cf
Routing by Stor-Ind method, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs
Peak Elev= 2,761. 30'@ 24.05 hrs Surf.Area= 4,166 sf Storage= 12,700 cf
Plug-Flow detention time= 1,750.2 min calculated for 1,061 cf (8% of inflow)
Center-of-Mass det. time= 1,432.1 min ( 2,201.2 - 769.1 )
Volume Invert Avail.Storage Storage Description
#1 2,756.00' 18,135 cf Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)
2,756.00 508 176.0 0 0 508
2,757.00 1,148 240.0 807 807 2,637
2,758.00 1,914 268.0 1,515 2,321 3,797
2,759.00 2,754 291.0 2,321 4,643 4,858
2,760.00 3,456 310.0 3,098 7,741 5,815
2,760.25 3,588 314.0 880 8,621 6,028
2,760.50 3,722 318.0 914 9,535 6,244
2,761.00 3,995 326.0 1,929 11,464 6,685
2,761.50 4,280 335.0 2,068 13,532 7,186
2,762.00 4,572 343.0 2,213 15,745 7,650
2,762.50 4,991 398.0 2,390 18,135 10,898
Device Routing Invert Outlet Devices
#1 Device 2 2,755.70' 24.00" x 142.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,755.36' S= 0.0024'/' Cc= 0.900
n= 0.010 PVC, smooth interior
#2 Seconda ry 2,761.50' 8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
#3 Secondary 2,762.00' 15.0' long x 12.0' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64
#4 Primary 2,760.25' 6.00" x 28.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,759.75' S= 0.01797' Cc= 0.900
n= 0.010 PVC, smooth interior
#5 Device 4 2,759.25' 0.50" Horiz. Orifice/Grate Limited to weir flow C= 0.600
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 1 yr Rainfall=3.00"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Primary OutFlow Max=0.01 cfs @ 24.05 hrs HW=2,761.30' (Free Discharge)
L-4=Culvert (Passes 0.01 cfs of 0.85 cfs potential flow)
t5=0rifice/Grate (Orifice Controls 0.01 cfs @ 4.94 fps)
econdary OutFlow Max=0.00 cfs @ 0.00 hrs HW=2,756.00' (Free Discharge)
Sharp-Crested Rectangular Weir ( Controls 0.00 cfs)
Ah. 1=Culvert (Controls 0.00 cfs)
3=Broad-Crested Rectangular Weir (Controls 0.00 cfs)
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type 11 24-hr 10yr Rainfall=5.07"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Pond Pond: Pond
Hydrograph
¦ Inflow
- ».?z ors - --i ? Outflow
¦ Primary
nfl?wArea=4,814'sf
I
¦ Secondary
12
!Peak-Elev=2,761,.69'
.
,o Storage=?14,360'cf
9-
8'
v
3 6
0
a 5
4-
2.20 ds
2.20 cfa
2
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60
Time (hours)
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 10yr Rainfall=5.07"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Pond Pond: Pond
Inflow Area = 60,814 sf, 94.60% Impervious, Inflow Depth = 4.60" for 10yr event
Inflow = 11.12 cfs @ 11.93 hrs, Volume= 23,323 cf
Outflow = 2.20 cfs @ 12.04 hrs, Volume= 10,682 cf, Atten= 80%, Lag= 6.6 min
Primary = 0.01 cfs @ 12.04 hrs, Volume= 1,235 cf
Secondary = 2.20 cfs @ 12.04 hrs, Volume= 9,447 cf
Routing by Stor-Ind method, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs
Peak Elev= 2,761.69' @ 12.04 hrs Surf.Area= 4,390 sf Storage= 14,360 cf
Plug-Flow detention time= 426.5 min calculated for 10,682 cf (46% of inflow)
Center-of-Mass det. time= 297.5 min ( 1,052.4 - 755.0)
Volume Invert Avail.Storage Storage Description
#1 2,756.00' 18,135 cf Custom Stage Data ( Irregular) Listed below (Recalc)
Elevation Surf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)
2,756.00 508 176.0 0 0 508
2,757.00 1,148 240.0 807 807 2,637
2,758.00 1,914 268.0 1,515 2,321 3,797
2,759.00 2,754 291.0 2,321 4,643 4,858
2,760.00 3,456 310.0 3,098 7,741 5,815
2,760.25 3,588 314.0 880 8,621 6,028
2,760.50 3,722 318.0 914 9,535 6,244
2,761.00 3,995 326.0 1,929 11,464 6,685
2,761.50 4,280 335.0 2,068 13,532 7,186
2,762.00 4,572 343.0 2,213 15,745 7,650
2,762.50 4,991 398.0 2,390 18,135 10,898
Device Routing Invert Outlet Devices
#1 Device 2 2,755.70' 24.00" x 142.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,755.36' S= 0.00247' Cc= 0.900
n= 0.010 PVC, smooth interior
#2 Secondary 2,761.50' 8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
#3 Secondary 2,762.00' 15.0' long x 12.0' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64
#4 Primary 2,760.25' 6.00" x 28.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,759.75' S=0.0179'/' Cc= 0.900
n= 0.010 PVC, smooth interior
#5 Device 4 2,759.25' 0.50" Horiz. Orifice/Grate Limited to weir flow C= 0.600
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type 11 24-hr 10yr Rainfall=5.07"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Primary OutFlow Max=0.01 cfs @ 12.04 hrs HW=2,761.69' (Free Discharge)
t4=Culvert (Passes 0.01 cfs of 1.03 cfs potential flow)
L5=Orifice/Grate (Orifice Controls 0.01 cfs @ 5.78 fps)
econdary OutFlow Max=2.17 cfs @ 12.04 hrs HW=2,761.69' (Free Discharge)
Sharp-Crested Rectangular Weir (Weir Controls 2.17 cfs @ 1.43 fps)
1=Culvert (Passes 2.17 cfs of 6.60 cfs potential flow)
3=13road-Crested Rectangular Weir (Controls 0.00 cfs)
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 0 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Pond Pond: Pond
Hydrograph
" -- - _ - -- -- --- - - - --- --
'. ' 1lnf1bW''Area-6081;
18
- - -e - - I - -- t---
17 14.33 ' cfs 'Pek- ? -- ?5?
15 14.3 2 da Storage 16, -1---- f
14
13 -; -
12
v 10
`p 8 - ___
7
g
5 -
4 - I I I I -I I I
3
2
Outflow
aIN Inflow
Primary
Secondary
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56 58 60
Time (hours)
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type 11 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 02007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Summary for Pond Pond: Pond
Inflow Area = 60,814 sf, 94.60% Impervious, Inflow Depth = 6.98" for 100yr event
Inflow = 16.52 cfs @ 11.93 hrs, Volume= 35,385 cf
Outflow = 14.33 cfs @ 11.96 hrs, Volume= 22,741 cf, Atten= 13%, Lag= 1.7 min
Primary = 0.01 cfs @ 11.96 hrs, Volume= 1,243 cf
Secondary = 14.32 cfs @ 11.96 hrs, Volume= 21,498 cf
Routing by Stor-Ind method, Time Span= 0.00-60.00 hrs, dt= 0.01 hrs
Peak Elev= 2,762.15'@ 11.96 hrs Surf.Area= 4,692 sf Storage= 16,417 cf
Plug-Flow detention time= 272.7 min calculated for 22,738 cf (64% of inflow)
Center-of-Mass det. time= 168.9 min ( 915.3 - 746.4 )
Volume Invert Avail.Storage Storage Description
#1 2,756.00' 18,1 35 cf Custom Stage Data (Irregular) Listed below (Recalc)
Elevation Su rf.Area Perim. Inc.Store Cum.Store Wet.Area
(feet) (sq-ft) (feet) (cubic-feet) (cubic-feet) (sq-ft)
2,756.00 508 176.0 0 0 508
2,757.00 1,148 240.0 807 807 2,637
2,758.00 1,914 268.0 1,515 2,321 3,797
2,759.00 2,754 291.0 2,321 4,643 4,858
2,760.00 3,456 310.0 3,098 7,741 5,815
2,760.25 3,588 314.0 880 8,621 6,028
2,760.50 3,722 318.0 914 9,535 6,244
2,761.00 3,995 326.0 1,929 11,464 6,685
2,761.50 4,280 335.0 2,068 13,532 7,186
2,762.00 4,572 343.0 2,213 15,745 7,650
2,762.50 4,991 398.0 2,390 18,135 10,898
Device Routing Invert Outlet Devices
#1 Device 2 2,755.70' 24.00" x 142.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,755.36' S= 0.0024T Cc= 0.900
n= 0.010 PVC, smooth interior
#2 Secondary 2,761.50' 8.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s)
#3 Secondary 2,762.00' 15.0' long x 12.0' breadth Broad-Crested Rectangular Weir
Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60
Coef. (English) 2.57 2.62 2.70 2.67 2.66 2.67 2.66 2.64
#4 Primary 2,760.25' 6.00" x 28.0' long Culvert CPP, square edge headwall, Ke= 0.500
Outlet Invert= 2,759.75' S= 0.01797' Cc= 0.900
n= 0.010 PVC, smooth interior
#5 Device 4 2,759.25' 0.50" Horiz. Orifice/Grate Limited to weir flow C= 0.600
Best Buy Wet Basin-Sand Filter Drainage Area 1 v4 Type// 24-hr 100yr Rainfall=7.46"
Prepared by HydroCAD SAMPLER 1-800-927-7246 www.hydrocad.net Printed 11/14/2008
HydroCAD® 8.50 SAMPLER s/n 026033 © 2007 HydroCAD Software Solutions LLC
This report was prepared with the free HydroCAD SAMPLER, which is licensed for evaluation and
educational use only. For actual design or modeling applications you must use a full version of HydroCAD
which may be purchased at www.hydrocad.net. Full programs also include complete printed
documentation, technical support, training materials, and additional features which are essential for actual
design work.
Primary OutFlow Max=0.01 cfs @ 11.96 hrs HW=2,762.14' (Free Discharge)
t- Culvert (Passes 0.01 cfs of 1.21 cfs potential flow)
5=0rifice/Grate (Orifice Controls 0.01 cfs @ 6.63 fps)
econdary OutFlow Max=14.25 cfs @ 11.96 hrs HW=2,762.14' (Free Discharge)
Sharp-Crested Rectangular Weir (Passes 12.14 cfs of 13.30 cfs potential flow)
1=Culvert (inlet Controls 12.14 cfs @ 3.86 fps)
3=Broad-Crested Rectangular Weir (Weir Controls 2.11 cfs @ 0.98 fps)