HomeMy WebLinkAbout15 - Design Report - Boulder Creek - Stormwater STORM WATE R MANAGEMENT
DESIGN REPORT
BOULDER CREEK SUBDIVISION
Prepared for:
Rosa-Johnson Development, LLC.
125 Central Avenue, Bozeman, MT 59718
Prepared by:
C&H Engineering and Surveying, Inc.
1091 Stoneridge Drive, Bozeman, MT 59718
(406) 587-1115 -_
V
MAN f
r
Project Number: 14624
JUNE 2015
INTRODUCTION
The Boulder Creek Subdivision is a 63 lot residential subdivision located east of Laurel Parkway
and north of Annie Street. The 35.34-acre development is situated in the South Half of Section 4,
Township 2 South, Range 5 East of P.M.M., Gallatin County, Montana. This project will require
connection to existing City of Bozeman water and sanitary sewer systems.
The software Autodesk Storm Sanitary Analysis (SSA)was used for all pipe sizing calculations in
this report. The results from the model can be found in Appendix C of this report. The model
report contains both input data and model run output for each drainage area, pipe, inlet and
manhole. C&H developed spreadsheets were used for all other calculations including pipe outlet
capacities, gutter flow depth and detention pond sizing. Each drainage area, weighted C value,
total acreage and storm peak runoff was calculated using a C&H developed excel spreadsheet prior
to inputting the data into SSA. The spreadsheet printouts and all other items mentioned above can
be found in Appendices B, C and D.
STORMWATER MANAGEMENT
Design of the stormwater facilities for this project was based on the City of Bozeman Design
Standards and Specifications Policy, March 2004 including Addendums I through 5.
The subdivision has been divided into separate drainage areas as shown in Figure DA1 in
Appendix B. A composite "C" runoff coefficient was calculated for each drainage area along
with the post-development time of concentration. Inlets will be placed along roadways at
intervals to ensure the gutter capacity is not exceeded (see gutter capacity spreadsheet Appendix
B). Per the City of Bozeman Design Standards, storm sewer facilities shall be sized for the
25-year storm event. Curbs can flow at a depth up to 0.15 feet below the top of curb elevation.
Flows were calculated at a point just upstream of the inlets to ensure adequate capacity. Detailed
calculations for the composite "C" factor, time of concentration, and curb depth check for each
drainage area can also be found in Appendix B.
PVC pipe will be used to connect the inlets to manholes and ponds. Per City of Bozeman Design
Standards,the pipe shall be sized for the 25-year storm event. The minimum pipe size shall be 12
Design Report-Page 2 of 8
inch for inlets and 15 inch for mains within the storm drain system. At the design flow, a
minimum of 3 feet per second of velocity is required to prevent sedimentation in the pipe system.
Each inlet will have a 9 inch sump for sediment collection as well. Detailed calculations for
design flow, peak capacity, and velocity for each pipe section can be found in Appendix C along
with the SSA report which details pipe and inlet results and characteristics.
Retention ponds are proposed in the design to retain stormwater as it percolates into the soil and
evaporates. Detention ponds are also proposed to treat stormwater prior to discharging it to
Baxter Creek. Design water depth calculations did not exceed 1.5 ft. with the exception of
Detention Pond 5 and existing Retention Pond 2. In cases where detention pond water depths
exceeds 1.5 ft. a 4 ft. fence will be installed around the ponds perimeter. Retention ponds were
sized per City of Bozeman Design Standards to handle the entire volume from the 10-year, 2-hour
storm event. Detention ponds were also sized per City of Bozeman Design Standards. The
pre-developed runoff rate was calculated and a discharge structure was then designed to limit the
outfall from the detention pond to the pre-developed runoff rate. The release volume is subtracted
from the runoff volume to calculate the required storage. The storm duration was increased in the
detention pond spreadsheet until the maximum required storage was calculated. Detailed
calculations for the detention and retention pond volumes can be found in the spreadsheet printout
in Appendix D.
STORMWATER DESIGN
Stormwater runoff from the subdivision will be conveyed to one of four detention/retention
facilities. A plan view of the site highlighting the drainage areas and the stormwater features is
included in Appendix B (Figure DA I).
The eastern side of the site will drain into Detention Pond 5 and includes drainage areas:DA 1,DA
4, DA 5, DA 6 and DA 7. The east side of the four one acre lots located in the northeast of the
subdivision (DA 9) will drain to Retention Pond 7. Drainage Areas 2 and 3 located in the
southeast of the site will drain to Detention Pond 6. Existing Retention Pond 2 (Detention Pond
#8) which was installed as a temporary retention facility in Laurel Glen Phase 2 will be converted
to a Detention facility and Drain DA 8 and DA 34E, consisting of drainage from Laurel Parkway,
Design Report-Page 3 of 8
a small portion of Oak Street and Block 34 (Creekstone Condos). Major drainage features of area
DA 34E were completed during Laurel Glen Phase 2.
DETENTION POND #5
Detention Pond #5 will retain and release runoff from Drainage Areas DA 1, DA 4, DA 5, DA 6
and DA 7. These drainage areas combined have a total area of 14.04 acres and a composite "C"
runoff coefficient of 0.48. The pre-developed runoff rate was calculated to be 1.72 cfs. (See
Appendix D for detailed calculations). The storage volume was computed by increasing the
storm duration and computing the runoff volume minus the release volume. The release rate is
equal to the pre-developed runoff rate. The maximum storage required occurs at a storm duration
of 50 minutes and is equal to 9,523 cubic feet. Detention Pond #5 has a volume of 10,262 cubic
feet. An outlet structure will be constructed for the pond and will have an 18 inch outfall pipe.
This pipe is sized to carry the 25 year flow as required by the City of Bozeman Design Standards.
A weir will be constructed in the outlet structure to limit the runoff to the pre-developed flow rate.
This weir will have a slot width of 3.4 inches to limit the discharge to 1.72 cfs. (See Appendix D
for detailed calculations).
DETENTION POND #5 PIPE SIZING
Two separate drainage systems drain into Detention Pond #5 the north system and the southeast
system. Drainage originating from the southeast of the pond from drainage area DA 1 is
conveyed via a 15 inch pipe from Storm Inlet#6 to SDMH 6. The 15 inch pipe drains a total area
of 4.01 acres. The time of concentration for this pipe is equal to the time of concentration of
DA 1 which is 22.90 minutes. At this time of concentration, the calculated peak flow rate is 2.66
cfs. (See Appendix C for detailed calculations). This pipe has a design capacity of 5.72 cfs and a
travel time of 0.15 minutes. A 15 inch pipe will be installed from SDMH 6 to SDMH 5 and will
continue to convey runoff from Drainage Area 1. The pipe will be upsized to an 18" pipe
downstream from Storm Inlet 5 and the rest of the pipes from this inlet to the detention pond will
be sized as 18" PVC drain pipe. All pipe travel times, diameters, peak and design flow rates and
times to peak flow occurrence can be found in the SSA report in Appendix C on the Pipe Results
page. Storm Inlet 5 will drain runoff from Drainage Area DA 4. The system picks up more flow
downstream from drainage areas DA 5 and DA 6 at inlets 4 and 3 respectively. At this location
Design Report-Page 4 of 8
the system is carrying flows from all upstream drainage areas and experiences the maximum flow
rate in the entire system. This pipe from Storm Inlet 3 to Detention Pond #5 is sized at 18" and
has a capacity of 15.65 cfs. The pipe experiences a peak flow rate of 7.87 cfs during the model
run for the 25 year COB storm event which is 50% of the total pipe capacity.
Drainage from the north system originating from Oak Street and its adjacent lots also enters
Detention Pond#5. Drainage area DA 7 is collected at storm inlet 1. Drainage from this inlet is
conveyed to SDMH 10 and then SDMH 9 along the north side of Oak Street before it is routed into
Detention Pond#5. The time to peak flow occurrence happens at 21 minutes and the inlet pipe to
Detention Pond#5 experiences a maximum flow at this time of 2.04 cfs. All pipes in this section
are sized at 15" PVC. (See Appendix D for detailed calculations).
OUTLET STRUCTURE AND PIPING—DETENTION POND #5
An outlet structure and piping will be installed in the northwest corner of Detention Pond#5. The
outlet structure will be sized per City of Bozeman Design Standards and have a slot width of 3.4
inches at the outlet weir to limit the runoff to the pre-developed runoff rate. The outlet pipe will
be sized as an 18 inch pipe,which at the 1.19%design slope has a maximum capacity of 12.33 cfs.
This capacity exceeds the 25 year design peak flow rate of 9.49 cfs which includes peak flow from
both the north and southeast systems. As such,this outlet pipe will be adequately sized to provide
overflow capacity from Detention Pond #5 into Baxter Creek. (See Appendix D for detailed
detention pond calculations).
DETENTION POND #6
Detention Pond #6 will retain and release runoff from Drainage Areas DA 2 and DA 3. These
drainage areas combined have a total area of 4.33 acres and a composite "C" runoff coefficient of
0.52. The pre-developed runoff rate was calculated to be 0.53 cfs. (See Appendix D for detailed
calculations). The storage volume was computed by increasing the storm duration and computing
the runoff volume minus the release volume. The release rate is equal to the pre-developed runoff
rate. The maximum storage required occurs at a storm duration of 55 minutes and is equal to
3,235 cubic feet. Detention Pond #6 has a volume of 3,601 cubic feet. An outlet structure will
be constructed for the pond and will have a 15 inch outfall pipe. This pipe is sized to carry the 25
Design Report-Page 5 of 8
is sized to carry the 25 year flow as required by the City of Bozeman Design Standards. A weir
will be constructed in the outlet structure to limit the runoff to the pre-developed flow rate. This
weir will have a slot width of 1 inch to limit the discharge to 0.53 cfs. (See Appendix D for
detailed calculations).
DETENTION POND #6 PIPE SIZING
Detention Pond#6 was sized in the same manner as Detention Pond#5 and carries a much smaller
portion of the overall drainage from the site. Due to the site characteristics and street locations
Detention Pond#5 and its associated system drains the majority of the site. Runoff from drainage
areas DA 2 and DA 3 will flow into Detention Pond #6. All pipes for this section will be 15"
PVC. The Storm Inlets 9 and 10 drain drainage areas DA 3 and DA 2 respectively. The pipe
containing the highest flow in this system is the 37 ft. section of pipe running from Inlet 9 to
Detention Pond #6. This section of pipe has a capacity of 4.57 cfs (25 year storm event) and
experienced a peak flow of 2.70 efs during the model run which represents 59% of the overall
capacity.
OUTLET STRUCTURE AND PIPING—DETENTION POND #6
An outlet structure and piping will be installed on the northwest side of Detention Pond#6. The
outlet structure will be sized per City of Bozeman Design Standards and a slot width of I inch will
be used to limit the runoff to the pre-developed runoff rate. The outlet pipe will be sized as a 15
inch pipe which at the 0.54%design slope has a maximum capacity of 5.11 cfs. This exceeds the
25 year design peak flow rate of 2.70 cfs and will adequately provide overflow capacity from the
detention pond. (See Appendix D for detailed detention pond calculations).
DETENTION POND #8
Detention Pond #8 was originally built during Laurel Glen Phase 2 construction and was
constructed as a temporary retention facility, as discussed in the C&H Design report dated October
2004. In the report the pond is referred to as Temporary Retention Pond#2. Detention Pond#8
will retain and release runoff from Drainage Areas DA 34E and DA 8. These drainage areas
combined have a total area of 5.86 acres and a composite"C"runoff coefficient of 0.58. Note that
the weighted "C" value of 0.72 used for the Laurel Parkway portion of DA 8 was taken directly
Design Report-Page 6 of 8
from the original C&H drainage report from 2004. The pre-developed runoff rate was calculated
to be 1.11 efs. (See Appendix D for detailed calculations). The storage volume was computed
by increasing the storm duration and computing the runoff volume minus the release volume.
The release rate is equal to the pre-developed runoff rate. The maximum storage required occurs
at a storm duration of 50 minutes and is equal to 4,064 cubic feet. Detention Pond #8 has a
volume of 5,543 cubic feet at a 2 ft. depth as field surveyed and calculated in Autodesk Civil 3D
software. An outlet structure will be constructed in the pond and will have a 15 inch outfall pipe.
This pipe is sized to carry the 25 year flow as required by the City of Bozeman Design Standards.
A weir will be constructed in the outlet structure to limit the runoff to the pre-developed flow rate.
This weir will have a slot width of 2.1 inches to limit the discharge to 1.08 cfs. (See Appendix D
for detailed calculations).
DETENTION POND #8 PIPE SIZING
Runoff from drainage areas DA 8 and DA 34E will flow into Detention Pond #8. All pipes
upstream of Detention Pond#8 are proposed to be 15"PVC. Drainage area DA 8 drains to Storm
Inlet 8 located to the east of the site on the south side of Oak Street approximately 123 ft. from the
property boundary of Boulder Creek Subdivision. The pipe containing the highest flow in this
system is the 38 ft. section of pipe running from SDMH 8 to Detention Pond #8. This section of
pipe has a capacity of 5.74 cfs (25 year storm event) and experienced a peak flow of 3.46 cfs
during the model run which represents 61% of the overall capacity.
OUTLET STRUCTURE AND PIPING—DETENTION POND #8
An outlet structure and piping will be installed on the northwest side of Detention Pond 48. The
outlet structure will be sized per City of Bozeman Design Standards and a slot width of 2.1 inches
will be used to limit the runoff to the pre-developed runoff rate. The outlet pipe will be sized as a
15 inch pipe which at the 0.59% design slope has a maximum capacity of 5.34 cfs. This exceeds
the 25 year design peak flow rate of 4.5 cfs and will adequately provide overflow capacity from the
detention pond. (See Appendix D for detailed detention pond calculations).
Design Report-Page 7 of 8
LEGEND a` or o
EXISTING SPOT ELEVATION U951KS
A.
x(100.00) PROPOSED SPOT ELEVATION CHANCIER
T1 EXISTING POWER BOX[IOSimG m[PHONE BoxEXISTING ELECTRIC BOX
1XISTWC SANITARY SEWER MANHOLE
Sheet 1 of I
!)"' EXISTING SANITARY SEWER CLEMOUT
iXY EXISTING FIRE HYDRANT SOMH 10 Itr STA 6.151(20.99Y)
STORM MET 2(W)SM p.4e.70 1].OY SDMH 7 ST.0.6110 e,19T1} SOMN 9 4e' SU].(0.9] 70.801. - D m�E
EXISTING WATER VALVE 4 �2� !L OUT
U 1/2 64 IF OF]6'x
FL OUT 64573/67(IV) R m 47Sa.52(15•) R IN([):1733.ta(f5--) � 58 1/1-RCP CULKRT W vnmi
39 EXISTING Cu'W STOP F FL OUT 47a.7l2 15 it OUT ;4131.73(1]' FL our(W}Y7]I,]p(15)
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EXISTING LIGHT POLE
LIE E:iTA"; -
13' EXISTING STORM INLET It
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PROPOSED STORM INLET '-- -- - _ _-- - -
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PROPOSED UNITARY SEWER CLEANOUT I OT_ R a2 7 IS-) OF Sa•%6B• ] !l W(S):17aS.e.(IV)
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CPA CULVERT WITH i R OUT(W):47a524(le•)I •'�,` F.I.CUT IJ 4]_5.5] W 9
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W-PROPOSED WATER SERVICE w it:
e'w-PROPOSED S WATER MAIN sum [I.,10.A +5.011) ` II -~ -"
-4-SS-PROPOSED 4•SANITARY SEWER SERVICE (U4 1. 4B' S1A 7.1 .M Ia.4]R) I I ;^t
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PROPOSED SWALE/RETENTION POND CONTOUR , • j Nwk4 - -�
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DRAINAGE MAP
CI,O SCALE:1-=100'i
!Baas Datic 1/22/15
DA1
#14624
DRAINAGE AREA # 1
Contributing Area C Area (11'2) C * Area Composite ROW
ROW 0.7375 52113 38433 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 9100 1820 0.7375
Lots 0.35 113357 39675
Total 174570 79928.3
C = Weighted C Factor 0.46
A=Area(acres) 4.01
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D1/2/S1/3
Storm
S = Slope of Basin(%) 0.5 Return Cf
C =Rational Method Runoff Coefficient U..35 2 to 10 1
Cf= Frequency Adjustment Factor '1.1 11 to 25 1.1
D =Length of Basin(ft) 114 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 17.99
Tc Gutter Flow
Tc= L/V/60
V = (1.486/n)R2/3 S1/2
n=Mannings Coefficient 0.013
R=Hydraulic Radius A/P (ft) 0.11 (0.15' below top of curb)
S = slope (ft/ft) 0.009
L= length of gutter (ft) 838
V =mean velocity(ft/s) 2.84
Tc Gutter Flow(minutes) = 4.91
Tc Total (Overland + Gutter)= 22.90.
Q = CIA
C = Weighted C Factor 046 (calculated above)
I= 0.78 Tc o.64(in/hr) 1.44
Drainage Area#1
A = area (acres) 4.01
Qrequired (CfS) = 2.65
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR"'S"
n=Mannings Coefficient 0.013
A = area(fe) 1.24
P =wetted perimeter (ft) 9.23
R=Hydraulic Radius AT (ft) 0.13
S = slope (ft/ft) 0.009
Qprovided (CfS) = 3.53
GUTTER HASADEQUATE CAPACITY
Drainage Area#1
DRAINAGE AREA # 2
Contributing Area C Area(ft 2) C * Area Composite ROW
ROW 0.7375 67847 50037 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3000 600 0.7375
Lots 0.35 104251 36488
Total 175098 87125
C = Weighted C Factor 0.50
A=Area(acres) 4.02
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc = 1.87 (1.1-CC)D1/2/S1/3
Storm
S = Slope of Basin (%) 0.5 Return Cf
C =Rational Method Runoff Coefficient 0.35 2 to 10 1
Cf= Frequency Adjustment Factor L l 11 to 25 1.1
D =Length of Basin (ft) 114 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 17.99
Tc Gutter Flow (West on Babcock)
Tc=L/V/60
V = (1.486/n)R2i3 S11
n=Mannings Coefficient 0.013
R=Hydraulic Radius A/P (ft) 0.13 (0.15'below top of curb)
S = slope (ft/ft) 0.006
L=length of gutter (ft) 1061
V =mean velocity(ft/s) 2.32
Tc Gutter Flow(minutes)= 7.61
Tc Total (Overland+ Gutter)
Q = CIA
C = Weighted C Factor t �R ''
g �:,.:�Q.�O'�(calculated above)
I = 0.78 Tc a64(in/hr) � )(:
Drainage Area#2
A = area (acres) 4.02
Qrequired (CfS) = 2.69
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR2i3SiI
n= Mannings Coefficient 0.013
A= area(ft) 1.24
P =wetted perimeter (ft) 9.23
R= Hydraulic Radius AT (ft) 0.13
S = slope (ft/ft) 0.006
Qprovided (efS) = 2.88
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#2
DRAINAGE AREA 4 3
Contributing Area C Area(ft 2) C * Area Composite ROW
ROW 0.7375 13319 9823 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 0 0 0.7375
Lots 0.35 0 0
Total 13319 9822.76
C = Weighted C Factor 0.74
A=Area(acres) 0.34.
Required Gutter/Pine Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CC)D1/2/S1/3
Storm
S = Slope of Basin(%) 0.5 Return Cr
C =Rational Method Runoff Coefficient 0.35 2 to 10 1
Cf=Frequency Adjustment Factor 11 11 to 25 1.1
D = Length of Basin (ft) 0 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 0400
Tc Gutter Flow (West on Babcock)
Tc =LN/60
V = (1.486/n)R2' S"
n= Mannings Coefficient 0.013
R=Hydraulic Radius A/P (ft) 0.13 (0.15'below top of curb)
S = slope (ft/ft) 0.006
L= length of gutter(ft) 182
V =mean velocity(ft/s) 2.32
Tc Gutter Flow(minutes)
Tc Total (Overland+ Gutter)
Q = CIA
C = Weighted C Factor 0.74 (calculated above)
I= 0.78 TC 0.64(in/hr) 9.03
Drainage Area#3
A = area (acres) 0.31
Qrequired (CfS) = 2.04
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR2/1SIi2
n=Mannings Coefficient 0.013
A = area(ft) 1.24
P =wetted perimeter(ft) 9.23
R= Hydraulic Radius A/P (ft) 0.13
S = slope (ft/ft) 0.006
Qprovided WS) = 2•88
GUTTER HASADEQUATE CAPACITY
Drainage Area#3
DRAINAGE AREA # 4
Contributing Area C Area(11'�) C * Area Composite ROW
ROW 0.7375 26062 19221 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 6194 1239 0.7375
Lots (Dense Residential) 0.5 84657 42329
Lots 0.35 0 0
Total 116913 62788
C = Weighted C Factor 0.54
A=Area(acres) 2.68
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc = 1.87 (1.1-CC)D"/S1/3
Storm
S = Slope of Basin (%) 0.5 Return Cr
C = Rational Method Runoff Coefficient 0.5 2 to 10 1
Cf=Frequency Adjustment Factor 1:1 11 to 25 1.1
D = Length of Basin (ft) 205 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes)
Tc Gutter Flow (West on Babcock)
Tc = L/V/60
V = (1.486/n)RZ/' S1i2
n=Mannings Coefficient 0 '3
R=Hydraulic Radius A/P (ft) =' '.0- 3, (0.15' below top of curb)
S = slope (ft/ft) 0.012
L= length of gutter (ft) 474
V =mean velocity (ft/s) ;: 1=4'
Tc Gutter Flow(minutes)
Tc Total (Overland + Gutter)
Q = CIA
C = Weighted C Factor ; .. 0.54 (calculated above)
Drainage Area#4
I = 0.78 Tc-0.64(in/hr) 1 .5
A = area (acres) 6 8
Qrequired (efs) = 2.20
Provided Gutter Capacity (flowinp, at 0.15' below top of curb)
Q = (1.486/n)AR2"Sli2
n=Mannings Coefficient 0.013
A= area(ft) 1.24
P = wetted perimeter(ft) 9.23
R= Hydraulic Radius A/P (ft) 0.13
S = slope (ft/ft) 0.012
Qprovided (cfs) = 4.07
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#4
DRAINAGE AREA # 5
Contributing Area C Area(It') C * Area Composite ROW
ROW 0.7375 43013 31722 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 6000 1200 0.7375
Lots 0.35 86101 30135
Total 135114 63057.4
C = Weighted C Factor OA7.
A=Area(acres) 3.10 0.47
Required Gutter/Pine Capacity (25-yr Storm)
Tc Overland Flow
Tc = 1.87 (1.1-CC)D1/2/S1/3
Storm
S = Slope of Basin(%) 0.5 Return Cf
C =Rational Method Runoff Coefficient q,35 2 to 10 1
Cf=Frequency Adjustment Factory 11 to 25 1.1
D =Length of Basin(ft) 114 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 17.99
Tc Gutter Flow (West on Babcock)
Tc =L/V/60
V = (1.486/n)R2/3 S12
n=Mannings Coefficient 0.013
R= Hydraulic Radius A/P (ft) 0.1 ; (0.15'below top of curb)
S = slope (ft/ft) 0.011
L= length of gutter (ft) 675
V =mean velocity (ft/s) 3.14
Tc Gutter Flow(minutes) 3.j 8
Tc Total (Overland + Gutter) _ 2.1.56
Q = CIA
C = Weighted C Factor r(calculated above)
I= 0.78 Tc o.64(in/hr)
Drainage Area#5
A = area (acres) 3.10
`[required (CfS) = 2.17
Provided Cutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR21S11
n= Mannings Coefficient 0.013
A = area(ft 2) 1.24
P =wetted perimeter (ft) 9.23
R= Hydraulic Radius A/P (ft) 0.13
S = slope (ft/ft) 0.011
QProvided (CfS) = 3.90
GUTTER HASADEQUATE CAPACITY
Drainage Area#5
DRAINAGE AREA 9 6
Contributing Area C Area(ft) C * Area Composite ROW
ROW 0.7375 26419 194'84 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 4294 859 0.7375
Lots 0.35 60876 21307
Total 91589 41649.4
C = Weighted C Factor O A
A = Area(acres) ?.10
Required Gutter/Pine Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CC)D1/2/S1/3
Storm
S = Slope of Basin (%) 0.5 Return Cr
C =Rational Method Runoff Coefficient 0:35 2 to 10 1
Cf= Frequency Adjustment Factor 1.1 11 to 25 1.1
D =Length of Basin (ft) 158 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes)
Tc Gutter Flow (West on Babcock)
Tc= L/V/60
V = (1.486/n)R2/3 Sl/2
n=Mannings Coefficient O.: il
R= Hydraulic Radius A/P (ft) 1.,t (0.15' below top of curb)
S = slope (ft/ft) 0.013
L= length of gutter (ft) 556
V =mean velocity (ft/s) ,:
Tc Gutter Flow(minutes)
Tc Total (Overland + Gutter)
Q = CIA
C = Weighted C Factor (calculated above)
I = 0.78 Tc-0*64(in/hr)
Drainage Area#6
A = area(acres) 2.10
Qrequired (Cfs) = 1.34
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR2"S"
n= Mannings Coefficient 0.013
A= area(ft) 1.24
P = wetted perimeter (ft) 9.23
R= Hydraulic Radius A/P (ft) 0.13
S = slope (ft/ft) 0.013
Qprovided WS) = 4.24
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#6
DRAINAGE AREA # 7
Contributing Area C Area (ft 2) C * Area Composite ROW (Oak Street)
South Side of Oak 0.75 22552 16914 ((0.95*22)+(0.2*8))/30
ROW (33' Street Width) 0.7375 8535 6295. 0.75
North Side Oak 0.95 11825 11234
Lots 0.35 22203 7771'
Lots (Dense Residential) 0.5 31150 15575' Composite ROW (33' Street Width)
Total 96265 57788.4 ((0.95*43)+(0.2*17))/60
0.7375
C = Weighted C Factor 0'
A =Area (acres) !.
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D1/2/S1/3
Storm
S = Slope of Basin (%) 0.5 Return Cr
C =Rational Method Runoff Coefficient 5 2 to 10 1
Cf= Frequency Adjustment Factor „� I�+ 11 to 25 1.1
D =Length of Basin (ft) 212 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 18
Tc Gutter Flow (West on Babcock)
Tc=L/V/60
V = (1.486/n)R2/3 S1/2
n=Mannings Coefficient 0.013`
R=Hydraulic Radius A/P (ft) 0.13 (0.15'below top of curb)
S = slope (ft/ft) 0.012
L= length of gutter(ft) 243
V =mean velocity(ft/s) 3.28
Tc Gutter Flow (minutes) _
Tc Total (Overland + Gutter) _
Q = CIA
Drainage Area# 7
C Weighted C Factor 0.60 (calculated above)
I = 0.78 Tc-0.64(in/hr) 1.57
A = area (acres) 2.21,
i
Qrequired (CfS) = 2.W$
Provided Gutter Capacity (flowinIz at 0.15' below top of curb)
Q = (1.486/n)AR"S"
n=Mannings Coefficient 0.013
A= area(fe) 1.24
P =wetted perimeter(ft) 9.23
R= Hydraulic Radius A/P (ft) 0.13
S = slope (ft/ft) 0.012
Qprovided WS) = 4.07
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#7
DRAINAGE AREA # 8
Contributing Area C Area(ft 2) C * Area Composite ROW (Oak Street)
Oak Street 0.675 25052 M910 ((0.95*28)+(0.2*32))/60
Laurel 0.72 63396 45645 0.675
Block 34 0.5 69209 34605
Lots 0.35 10734 3757
Total 16 8,;y1 100917
C = Weighted C Factor
A= Area (acres)
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Te = 1.87 (1.1-CCf)D1/2/S1/3
Storm
S = Slope of Basin(%) 0.5 Return Cf
C = Rational Method Runoff Coefficient 0.5 2 to 10 1
Cf= Frequency Adjustment Factor 1.1 11 to 25 1.1
D =Length of Basin(ft) 159 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) _ 0
Tc Gutter Flow (West on Babcock)
Te= LN/60
V = (1.486/n)R2' Sv2
n= Mannings Coefficient 0.013
R=Hydraulic Radius A/P (ft) 0.1 3 (0.15' below top of curb)
S = slope (ft/ft) 0.011
L= length of gutter(ft) 917
V =mean velocity (ft/s) 3.14,
Te Gutter Flow(minutes) = 4.86,
Tc Total (Overland + Gutter)
Q = CIA
C = Weighted C Factor (calculated above)
Drainage Area#8
I= 0.78 Tc-0.64(in/hr) 1.52
A = area (acres) 3.87
Qrequired (CfS) = 3.52
Provided Gutter Capacity (flowing, at 0.15' below top of curb)
Q = (1.486/n)AR2/3Sv2
n= Mannings Coefficient 0.013
A= area(ft 2) 1.24
P =wetted perimeter (ft) 9.23
R=Hydraulic Radius A/P (ft) 0.13
S = slope (ft/ft) 0.011
Qprovided (CfS) = 3.90
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#8
DRAINAGE AREA # 9
Contributing Area C Area (ft 2) C * Area Composite ROW
ROW 0.7375 0 0 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 5539 1108 0.7375
Lots(Dense Residential) 0.5 101653 50827
Total 107192 51934.3
C = Weighted C Factor 0.48
A = Area (acres) 2.46
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc = 1.87 (1.1-CC)D1/2/S1/3
Storm
S = Slope of Basin (%) 0.5 Return Cf
C = Rational Method Runoff Coefficient1Q, y 2 to 10 1
Cf=Frequency Adjustment Factor >?+,t 11 to 25 1.1
D =Length of Basin(ft) 557 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) _ ._ .
Tc Gutter Flow (West on Babcock)
Tc=L/V/60
V = (1.486/n)R2/3 Sv2
n=Mannings Coefficient 0.013
R=Hydraulic Radius A/P (ft) 0.1 3 (0.15'below top of curb)
S = slope (ft/ft) 0.005
L= length of gutter (ft) 0
V =mean velocity (ft/s) 2.12
Tc Gutter Flow(minutes) = 0.00
Tc Total (Overland+ Gutter) _ J.,76
Q = CIA
C = Weighted C Factor 0.4 8 (calculated above)
I= 0.78 Tc 0.64(in/hr) 1.02
Drainage Area#9
A area (acres) 2.46
Q (cfs) = 1.21
Drainage Area#9
DRAINAGE AREA # 34E
Contributing Area C Area(ft 2) C * Area Composite ROW
Lots(Dense Residential) 0.5 86961 43481
Total 86961 43480.5
C = Weighted C Factor 0.50
A = Area(acres) 2.0.0
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc = 1.87 (1.1-CCf)D1/2/S1/3
Storm
S = Slope of Basin (%) 0.5 Return Cr
C = Rational Method Runoff Coefficient 035 2 to 10 1
Cf=Frequency Adjustment Factor 4:3 11 to 25 1.1
D =Length of Basin (ft) 662 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) _ 43,34
Tc Gutter Flow (West on Babcock)
Tc =L/V/60
V = (1.486/n)R2/1 Sv2
n = Mannings Coefficient 0.013
R= Hydraulic Radius A/P (ft) 0,1; (0.15' below top of curb)
S = slope (ft/ft) 0.005
L= length of gutter (ft) 0
V =mean velocity(ft/s) 2.12
Tc Gutter Flow(minutes) = 40
Tc Total (Overland+ Gutter) = t>o11
Q = CIA
C = Weighted C Factor 1 (calculated above)
I= 0.78 Tc o.ba(in/hr)
A = area(acres)
Drainage Area#34E
Q (cfs) = 0.96
Drainage Area#34E
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Project Description
File Name............................................................................. 14624-BOULDER CREEK PROPOSED.SPF
Description............................................................................
G:\c&h\14\14624\STORMWATER\OVERALL DRAINAGE AREAS.dwg
rroject Options
FlowUnits.............................................................................CFS
Elevation Type...................................................................... Elevation
Hydrology Method..........................................._. . _ Rational
Time of Concentration(TOC)Method................................. User-Defined
Link Routing Method...........................................................Hydrodynamic
Enable Overflow Ponding at Nodes............... I YES
Skip Steady State Analysis Time Periods......................... NO
Analysis Options
Start Analysis On.................................................................. Feb 26,2015 00:00:00
End Analysis On................................................................... Feb 27,2015 00:00:00
Start Reporting On................................................................Feb 26,2015 00:00:00
Antecedent Dry Days............................................................0 days
Runoff(Dry Weather)Time Step..........................................0 01:00:00 days hh:mm:ss
Runoff(Wet Weather)Time Step........................................ 0 00:05:00 days hh:mm:ss
Reporting Time Step............................................................ 0 00:05:00 days hh:mm:ss
Routing Time Step................................................................30 seconds
Number of Elements
Qty
RainGages...........................................................................0
Su b b a s i n s..............................................................................8
Nodes.................................................................................... 19
Junctions...................................................................... 7
Outialls......................................................................... 4
Flow Diversions........................................................... 0
Inlets............................................................................ 8
StorageNodes............................................................. 0
Links...................................................................................... 17
Channels...................................................................... 2
Pipes............................................................................ 15
Pumps.......................................................................... 0
Orifices......................................................................... 0
Weirs....................»...................................................... 0
Outlets.......................................................................... 0
Pollutants.............................................................................. 0
LandUses............................................................................ 0
Rainfall Details
Return Period........................................................................ 25 year(s)
Subbasin Summary
SN Subbasin Area Weighted Total Total Total Peak Time of
ID Runoff Rainfall Runoff Runoff Runoff Concentration
Coefficient Volume
(ac) (in) (in) (ac-in) (cfs) (days hh:mm:ss)
1 (Drainage Areas).DA 1 4.01 0.4600 0.55 0.25 1.01 2.67 0 00:22:54
2(Drainage Areas).DA 2 4.02 0.5000 0.58 0.29 1.16 2.70 0 00:25:36
3(Drainage Areas).DA 3 0.31 0.7400 0.20 0.15 0.05 2.07 0 00:01:18
4(Drainage Areas).DA 4 2.68 0.5400 0.54 0.29 0.77 2.21 0 00:20:57
5{Drainage Areas).DA 5 3.10 0.4700 0.54 0.25 0.78 2.19 0 00:21:33
6{Drainage Areas}.DA 6 2.10 0.4500 0.56 0.25 0.53 1.33 0 00:23:53
7{Drainage Areas}.DA 7 2.21 0.6000 0.53 0.32 0.70 2.08 0 00:20:06
8{Drainage Areas).DA 8 2.48 0.6700 0.54 0.36 0.89 2.52 0 00:21:12
Node Summary
SN Element Element Invert Ground/Rim Initial Surcharge Ponded Peak Max HGL Max Min Time of Total Total Time
ID Type Elevation (Max) Water Elevation Area Inflow Elevation Surcharge Freeboard Peak Flooded Flooded
Elevation Elevation Attained Depth Attained Flooding Volume
Attained Occurrence
01) (ft) (ft) (ft) (It) (cfs) ((t) (ft) (ft) (days hh mm) ac in) (min)
1 SDMH 10 Junction 4734.50 4738.14 4734.50 4738.14 0.00 2.92 4735.28 0.00 2.86 0 00:00 0.00 000
2 SDMH 4 Junction 4737.22 4740.76 4737.22 4740.76 0.00 1.67 4737.60 0.00 3.16 0 00:00 0.00 0.00
3 SDMH 5 Junction 4740.69 4744.13 4740.69 4744.14 0.00 1.68 4741.11 0.00 3.02 0 00:00 0.00 0.00
4 SDMH 6 Junction 4742.03 4746.14 4742.03 4746.14 0.00 1.69 4742.49 0.00 3.65 0 00:00 0.00 0.00
5 SDMH 9 Junction 4733.23 4737.70 4733.23 4737.70 0.00 2.92 4733.79 0.00 3.91 0 00:00 0.00 0.00
6 SDMH 7 Junction 4733.52 4736.31 4733.52 4736.31 0.00 2.52 4734.22 0.00 2.09 0 00:00 0.00 0.00
7 SDMH 8 Junction 4732.87 4737.37 4732.87 4737.37 0.00 2.51 4733.56 0.00 3.81 0 00:00 0.00 0.00
8 Pond-5(1) Outfall 4731.80 2.91 4732.29
9 Pond_5(2) Outfall 4732.69 6.11 4733.346 10 Pond_ Outfall 4739.21 3.36 4739.95
11 Pond 8 Outfall 4732.57 2.50 4733.15
Link Summary
"N Element Element From To(Outlet) Length Inlet Outlet Average Diameter or Manning's Peak Design Flow Peak Flow/ Peak Flow Peak Flow Peak Flow Total Time Reported
ID Type (Inlet) Node Invert Invert Slope Height Roughness Flow Capacity Design Flow Velocity Depth Depth/Surcharged Condition
Node Elevation Elevation Ratio Total Depth
Ratio
(R) (ft) (0) N (in) (cfs) (cfs) (fUsec) (0) (min)
1 SDMH 10 to SDMH_9 Pipe SDMH 10 SDMH 9 251.00 4734.50 4733.23 0.5100 15.000 0.0130 2.92 4.59 064 4.38 0.67 0,53 0.00 Calculated
2 SDMH_4S to I 5 Pipe SDMH 4 STORM INLET 5 75.00 4737.22 4735.84 1.8400 15.000 0.0130 1.67 8.76 019 3.56 0.51 0.41 0.00 Calculated
3 SDMH-6-to-SDMH-5 Pipe SDMH 6 SDMH 5 131.00 4742.03 4740.69 1.0200 15.000 0.0130 1.68 6.53 0 26 4.33 0.44 0.35 0.00 Calculated
4 SDMH 7 to SI 2 Pipe STORMINLET_2 SDMH 7 17.00 4733.67 4733.52 0.9100 15.000 0.0130 2.52 6.15 041 3.32 0.74 059 0.00 Calculated
5SDMH 8 to_Pontl_8 Pipe SDMH_8 Pond 8 38.00 4732.87 4732.57 0.7900 15.000 0.0130 2.50 5.74 044 4.01 0.63 051 0.00 Calculated
6SDMH 8 to SDMH 7 Pipe SDMH_7 SDMH 8 107.00 4733.52 4732.87 0.6100 15.000 0.0130 2.51 5.03 050 3.60 0.69 055 0.00 Calculated
7 SDMH_9 to Pond-5 Pipe SDMH 9 Pond_50) 75.00 4733.23 4731.80 1.9100 15.000 0.0130 2.91 8.92 0.33 5.96 0.52 0A2 0.00 Calculated
8 SDMHS to SDMH4 Pipe SDMH 5 SDMH 4 266,00 4740.69 4737.22 1.3000 15.000 0.0130 1.67 7.38 023 4.90 0.40 0.32 0.00 Calculated
9 SI 1 to SDMH10 Pipe STORM INLET 1 SDMH 10 32.00 4734.75 4734.50 0.7800 15.000 0.0130 2.92 5.71 0 51 3.49 0.81 0.65 0.00 Calculated
10 SI 10 to SI 9 Pipe STORM INLET 10 STORM INLET 9 26.00 4740.20 4739.40 3.0800 15.000 0.0130 3.36 11.33 0.30 4.12 0.79 0.63 0.00 Calculated
11 SI_3 to Pond Pipe STORM INLET 3 Pond_5(2) 74.00 4734.38 4732.69 2.2800 18.000 0.0130 6.11 15.87 0.39 7.46 0.71 047 0.00 Calculated
12 SW to to SI 3 Pipe STORM INLET 4 STORM INLET 3 53.00 4734.67 4734.38 0.5500 18.000 0.0130 4.87 7.77 0 63 4.48 0.89 059 0.00 Calculated
13 SI5 to SI 4 Pipe STORM INLET 5 STORM INLET 4 233.00 4735.84 4734.67 0.5000 18.000 0.0130 2.77 7.44 037 2.84 0.82 0.55 0.00 Calculated
14 SI_6 to SDMH 6 Pipe STORM INLET 6 SDMH 6 37.00 4742.32 4742.03 0.7800 15.000 0.0130 1.69 5.72 029 3.65 0.50 040 0.00 Calculated
15 SI 9 to Pond Pipe STORM_INLET 9 Pond-6 35.00 4739.40 4739.21 0.5300 15.000 0.0130 3.36 4.70 0.72 3.80 0.85 0.68 0.00 Calculated
16 Gutter 1 Channel STORM INLET 5 STORM INLET 1 260.00 4739.66 4737.70 0.7500 6.120 0.0320 0.99 13.03 0.08 1.84 0.25 0.48 0.00
17 Gutter-2 Channel STORM INLET 6 STORM INLET 10 485.00 4746.34 4743.69 0.5500 6.120 0.0320 0.98 11.09 009 1.13 026 0.51 0.00
Inlet Summary
SN Element Inlet Manufacturer Inlet Number of Catchbasin Max(Rim) Initial Ponded Peak Peak Flow Peak Flow Inlet Allowable Max Gutter Max Gutter
ID Manufacturer Part Location Inlets Invert Elevation Water Area Flow Intercepted Bypassing Efficiency Spread Spread Water Elev.
Number Elevation Elevation by Inlet during Peak during Peak during Peak
Inlet Flow Flow Flow
(8) (4) A W) (cfs) (cfs) (cfs) N (0) (ft) (ft)
1 STORM INLET 1 NEENAH FOUNDRY R-3067-L On Sag 1 4734.75 4737.70 4734.75 10.00 3.00 NIA NIA NIA 9.00 7.92 4737.98
2 STORM INLET 3 NEENAH FOUNDRY R-3067-L On Sag 1 4734.38 4737.66 4734.38 10.00 1.33 NIA NIA NIA 9.00 3.89 4737.83
3 STORM INLET 4 NEENAH FOUNDRY R-3067-L On Sag 1 4734.67 4738.04 4734.67 10.00 2.19 NIA NIA NIA 9.00 6.09 4738.27
4 STORM INLET 5 NEENAH FOUNDRY R 3067 L Type L On Grade 1 4735.84 4739.66 4735.84 NIA 2.21 1.21 1.00 54.88 9.00 5.68 4739.88
5 STORM INLET 6 NEENAH FOUNDRY R 3067 L Type L On Grade 1 4742.32 4746.34 4742.32 NIA 2.66 1.69 0.98 63.33 9.00 7.30 4746.61
6 STORM INLET 2 NEENAH FOUNDRY R-3067-L On Sag 1 4733.67 4736.39 4733.67 10.00 2.52 NIA NIA NIA 9.00 6.87 4736.65
7 STORM INLET 10 NEENAH FOUNDRY R-3067-L On Sag 1 4740.20 4743.69 4740.20 10.00 3.49 NIA NIA NIA 9.00 8.93 4744.00
8 STORM-INLET 9 NEENAH FOUNDRY R-3067-L On Sag 1 4739.40 4743.69 4739.40 10.00 2.05 NIA NIA NIA 9.00 5.76 4743.91
Junction Input
SN Element Invert Ground/Rim Ground/Rim Initial Initial Surcharge Surcharge Ponded Minimum
ID Elevation (Max) (Max) Water Water Elevation Depth Area Pipe
Elevation Offset Elevation Depth Cover
(ft) (ft) (ft) (ft) (it) (ft) L4f_ !fl'1 (in)
1 SDMH 10 4734.50 4738.14 3.64 4734.50 0.00 4738.14 0.00 000 0.00
2 SDMH 4 4737.22 4740.76 3.54 4737.22 0.00 4740.76 0.00 0.00 0.00
3 SDMH 5 4740.69 4744.13 3.44 4740.69 0.00 4744.14 0.01 0.00 0.00
4 SDMH 6 4742.03 4746.14 4.11 4742.03 0.00 4746.14 0.00 0.00 0.00
5 SDMH 9 4733.23 4737.70 4.47 4733.23 0.00 4737.70 0.00 0.00 0.00
6 SDMH 7 4733.52 4736.31 2.79 4733.52 0.00 4736.31 0.00 0.00 0.00
7 SDMH 8 4732.87 4737.37 4.50 4732.87 0.00 4737.37 0.00 0.00 0.00
Junction Results
SN Element Peak Peak Max HGL Max HGL Max Min Average HGL Average HGL Time of Time of Total Total Time
ID Inflow Lateral Elevation Depth Surcharge Freeboard Elevation Depth Max HGL Peak Flooded Flooded
Inflow Attained Attained Depth Attained Attained Attained Occurrence Flooding Volume
Attained Occurrence
(cfs) (cfs) (ft) (ft) (ft) (ft) (ft) (ft) (days hh:mm) (days hh:mm) (ac-in) (min)
1 SDMH 10 2.92 0.00 4735.28 0.78 0.00 2.86 4734.57 0.07 0 00:22 0 00:00 0.00 0.00
2 SDMH 4 1.67 0.00 4737.60 0.38 0.00 3.16 4737.26 0.04 0 00:24 0 00:00 0.00 0.00
3 SDMH 5 1.68 0.00 4741.11 0.42 0.00 3.02 4740.73 0.04 0 00:23 0 00:00 0.00 0.00
4 SDMH 6 1.69 0.00 4742.49 0.46 0.00 3.65 4742.08 0.05 0 00:23 0 00:00 0.00 0.00
5 SDMH 9 2.92 0.00 4733.79 0.56 0.00 3.91 4733.28 0.05 0 00:22 0 00:00 0.00 0.00
6 SDMH 7 2.52 0.00 4734.22 0.70 0.00 209 4733.58 0.06 0 00:21 0 00:00 0.00 0.00
7 SDMH 8 2.51 0.00 4733.56 0.69 0.00 3.81 4732.93 0.06 0 00:21 0 00:00 0.00 0.00
Channel Input
SN Element Length Inlet Inlet Outlet Outlet Total Average Shape Height Width Manning's Entrance Exit/Bend Additional Initial Flap
ID Invert Invert Invert Invert Drop Slope Roughness Losses Losses Losses Flow Gate
Elevation Offset Elevation Offset
(ft) (ft) (ft) (ft) (ft) (ft) (%) (ft) (ft) (cfs)
1 Gufter_1 260.00 4739.66 3.82 4737.70 2.95 1.96 0.7500 User-Defined 0.510 16.500 0.0320 0.5000 0.5000 0.0000 0.00 No
2 Gutter-2 485.00 4746.34 4.02 4743.69 3.49 2.65 0.5500 User-Defined 0.510 16.500 0.0320 0.5000 0.5000 0.0000 0.00 No
Channel Results
SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Travel Peak Flow Peak Flow Total Time Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cis) (ft/sec) (min) (R) (min)
1 Gutler_1 0.99 0 00:21 13.03 0.08 1.84 2.36 0.25 0.48 0.00
2 Gutter 2 0.98 0 00:23 11.09 0.09 1.13 7.15 0.26 0.51 0.00
Pipe Input
SN Element Length Inlet Inlet Outlet Outlel Total Average Pipe Pipe Pipe Manning's Entrance Exit/Bend Additional Initial
ID Invert Invert Invert Invert Drop Slope Shape Diameteror Width Roughness Losses Losses Losses Flow
Elevation Offset Elevation Offset Height
(ft) (ft) (ft) (ft) (ft) (ft) (%) (in) (in) (cfs)
1 SDMH_10 to_SDMH_9 251.00 4734.50 0.00 4733.23 0.00 1.27 0.5100 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
2 SDMH4to SI_5 75.00 4737.22 0.00 4735.84 0.00 1.38 1.8400 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
3 SDMH__6__to_SDMH_5 131.00 4742.03 0.00 4740.69 0.00 1.34 1.0200 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
4 SDMH_7_to_SI_2 17.00 4733.67 0.00 4733.52 0.00 0.15 0.9100 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
5 SDMH8 to Pond 8 38.00 4732.87 0.00 4732.57 0.00 0.30 0.7900 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
6 SDMH_8^to_SDMH 7 107.00 4733.52 0.00 4732.87 0.00 0.65 0.6100 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
7 SDMH_9_-to_Pond 5 75.00 4733.23 0.00 4731.80 0.00 1.43 1.9100 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
8 SDMH5 to_SDMH4 266.00 4740.69 0.00 4737.22 0.00 3.47 1.3000 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
9 SI_1_to_^SDMH10 32.00 4734.75 0.00 4734.50 0.00 0.25 0.7800 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
10 SI_10_to_SI_9 26.00 4740.20 0.00 4739.40 0.00 0.80 3.0800 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
11 SI_3_to_Pond 74.00 4734.38 0.00 4732.69 0.00 1.69 2.2800 CIRCULAR 18.000 18.000 0.0130 0.5000 0.5000 0.0000 0.00
12 SI4toSI_3 53.00 4734.67 0.00 4734.38 0.00 0.29 0.5500 CIRCULAR 18.000 18.000 0.0130 0.5000 0.5000 0.0000 0.00
13 SI__57_to7_SI_4 233.00 4735.84 0.00 4734.67 0.00 1.17 0.5000 CIRCULAR 18.000 18.000 0.0130 0.5000 0.5000 0.0000 0.00
14 SI_6_to_SDMH_6 37.00 4742.32 0.00 4742.03 0.00 0.29 0.7800 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
15 SI 9 to Pond 35.00 4739.40 0.00 4739.21 0.00 0.19 0.5300 CIRCULAR 15.000 15.000 0.0130 0.5000 0.5000 0.0000 0.00
Flap No.of
Gate Barrels
• 1
No t
No 1
No 1
No 1
No 1
No 1
No 1
No 1
No 1
No 1
No 1
No 1
No 1
No 1
Pipe Results
SN Element Peak Time of Design Flow Peak Flow/ Peak Flow Travel Peak Flow Peak Flow Total Time Froude Reported
ID Flow Peak Flow Capacity Design Flow Velocity Time Depth Depth/ Surcharged Number Condition
Occurrence Ratio Total Depth
Ratio
(cfs) (days hh:mm) (cfs) (ft/sec) (min) (ft) (min)
1 SDMH_10_to_SDMH 9 2.92 0 00:22 4.59 0.64 4.38 0.96 0.67 0.53 0.00 Calculated
_2 SDMH_4_toSI_5 _ 1.67 0 00:24 8.76 0.19 3.56 0.35 0.51 0.41 0.00 Calculated
3 SDMH_6_to_SDMH_5 1.68 0 00:23 6.53 0.26 4.33 0.50 0.44 0.35 0.00 Calculated
4 SDMH7_to_SI_2 2.52 0 00:21 6.15 0.41 3.32 0.09 0.74 0.59 0.00 Calculated
M 5 SDH_6to_Pond_8 2.50 0 00:21 5.74 0.44 4.01 0.16 0.63 0.51 0.00 Calculated
6 SDMH_8 to_SDMH_7 251 0 00:21 5.03 0.50 3.60 0.50 0.69 0.55 0.00 Calculated
7 SDMH_9^_to_Pond_5 2.91 0 00:22 8.92 0.33 5.96 0.21 0.52 0.42 0.00 Calculated
8 SDMH5_to_SDMH4 1.67 0 00:23 7.38 0.23 4.90 0.90 0.40 0.32 0.00 Calculated
9 SI_1_to_SDMH10 2.92 0 00:21 5.71 0.51 3.49 0.15 0.81 0.65 0.00 Calculated
10 SI_10_to_SI_9 3.36 0 00:26 11.33 0.30 4.12 0.11 0.79 0.63 0.00 Calculated
11 SI_3_to_Pond 6.11 0 00:22 15.87 0.39 7.46 0.17 0.71 0.47 0.00 Calculated
12 SI_4 to_SI_3 4.87 0 00.22 7.77 0.63 4.48 0.20 0.89 0.59 0.00 Calculated
13 SI_5_to_SI_4 2.77 0 00:24 7.44 0.37 2.84 1.37 0.82 0.55 0.00 Calculated
14 SI_6_to_SDMF_6 1.69 0 00:23 5.72 0.29 3.65 0.17 0.50 0.40 0.00 Calculated
15 SI 9 to Pond 3.36 0 00:26 4.70 0.72 3.80 0.15 0.85 0.68 0.00 Calculated
Inlet Input
SIN Element Inlet Manufacturer Inlet Number of Catchbasin Max(Rim) Inlet Initial Initial Ponded Grate
ID Manufacturer Part Location Inlets Invert Elevation Depth Water Water Area Clogging
Number Elevation Elevation Depth Factor
_ (o) (ft) (It) (11) (ft) ((N) (%)
1 STORM INLET 1 NEENAH FOUNDRY R-3067-L On Sag 14734.75 4737.70 2.95 4734.75 0.00 10.00 0.00
2 STORM INLET 3 NEENAH FOUNDRY R-3067-L On Sag 1 4734.38 4737.66 3.28 4734.38 0.00 10.00 0.00
3 STORM INLET 4 NEENAH FOUNDRY R-3067-L On Sag 1 4734.67 4738.04 3.37 4734.67 0.00 10.00 0.00
4 STORM INLET 5 NEENAH FOUNDRY R 3067 L Type L On Grade 1 4735.84 4739.66 3.82 4735.84 0.00 N/A 0.00
5 STORM INLET 6 NEENAH FOUNDRY R 3067 L Type L On Grade 1 4742.32 4746.34 4.02 4742.32 0.00 N/A 0.00
6 STORM INLET 2 NEENAH FOUNDRY R-3067-L On Sag 1 4733.67 4736.39 2.72 4733.67 0.00 10.00 0.00
7 STORM_INLET 10 NEENAH FOUNDRY R-3067-L On Sag 1 4740.20 4743.69 3.49 4740.20 0.00 10.00 000
8 STORM-INLET 9 NEENAH FOUNDRY R-3067-L On Sag 1 4739.40 4743.69 4.29 4739.40 0.00 10.00 0.00
Inlet Results
SN Element Peak Peak Peak Flow Peak Flow Inlet Max Gutter Max Gutter Max Gutter Time of Total Total Time
ID Flow Lateral Intercepted Bypassing Efficiency Spread Water Elev. Water Depth Max Depth Flooded Flooded
Inflow by Inlet during Peak during Peak during Peak during Peak Occurrence Volume
Inlet Flow Flow Flow Flow
(cfs) (cfs) (cfs) (cfs) (%) (ft) (ft) ((t) (days hh,mm) (ao-in) (1»i11)_
1 STORM INLET 1 3.00 2.08 N/A N/A N/A 7.92 4737.98 0.26 0 00:21 0.00 0.00
2 STORM INLET 3 1.33 1.33 N/A N/A N/A 3.89 4737.83 0.17 0 00:22 0.00 0.00
3 STORM INLET 4 2.19 2.19 N/A N/A N/A 6.09 4738.27 0.23 0 00:22 0.00 0.00
4 STORM INLET 5 2.21 2.21 1.21 1.00 54.88 5.68 4739.88 0.22 0 00:24 0.00 0.00
5 STORM INLET 6 2.66 2.66 1.69 0.98 63.33 7.30 4746.61 0.27 0 00:23 0.00 0.00
6 STORM INLET 2 2.52 2.52 N/A N/A N/A 687 4736.65 0.26 0 00:21 0.00 0.00
7 STORM INLET 10 349 2.70 N/A N/A N/A 8.93 4744.00 0.31 0 00:26 0.00 0.00
8 STORM INLET 9 2.05 2.05 N/A N/A N/A 5.76 4743.91 0.23 0 00:26 0.00 0.00
DETENTION POND # 5
REQUIRED VOLUME
2. Calculate Area and Weighted C Factor(Post-Development)
Contributing Area C Area (ft2) C *Area
Lot 2 0.35 22203 7771
Lot 3 0.5 31150 15575
Lot 4 0.5 26662 13331
Lot 6 0.35 33308 11658
Lot 7 0.35 19939 6979
Lot 8 0.35 16043 5615
Lot 9 0.35 27568 9649
Lot 10 0.35 22767 7968
Lot 11 0.35 27352 9573
Lot 12 0.35 57995 20298
Lot 17 0.35 30816 10786
Lot 18 0.35 32524 11383
Lot 20 0.35 24817 8686
Lot 21 0.35 25200 8820
Isabella Sherwood ROW 3 0.74 52113 38564
Sherwood Abigail ROW 7 0.74 26062 19286
Abigail Saxon ROW 8 0.74 21254 15728
Sherwood Samantha ROW 4 0.74 21759 16102
Samantha ROW 5 0.74 18442 13647
Saxon ROW 6 0.74 7977 5903
Oak ROW 9 0.74 22552 16688
Oak ROW 10 0.95 11825 11234
Abigail ROW 0.74 8535 6316
OS B 0.2 3000 600
OS C 0.2 3100 620
OS D 0.2 4294 859
OS E 0.2 3000 600
OS F 0.2 3000 600
OS G 0.2 6194 1239
Total 611451 296077
A =Area(acres) 14.0370
C = Weighted C Factor 0.48
3. Calculate T, (Pre-Development)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D1/2/Sli3
-------............-----------------
Storm
S = Slope of Basin (%) 1 :Return (yrs) Cf
C = Rational Method Runoff Coefficient 0.2 !2 to 10 1
Cf= Frequency Adjustment Factor 1.1 :11 to 25 1.1;
D = Length of Basin (ft) 1512 26 to 50 1.2
'51 to 1001 25-
'•-------- --
_ ___ _ _
6. Calculate Required Pond Volume
Total Area (acres) = 14.04 acres
Weighted C = 0.48
Discharge Rate (cfs) = 1.72 cfs (Equal to Pre-Development Runoff Rate)
Duration(min) Duration(hrs) Intensity Q�� (cfs) Runoff Release Required
(in/hr) Volume Volume Storage (ft3)
46 0.77 0.76 5.17 14270 4756 9514
47 0.78 0.75 5.10 14377 4859 9518
48 0.80 0.74 5.03 14484 4963 9521
49 0.82 0.73 4.96 14589 5066 9523
50 0.83 0.72 4.90 14692 5169 9523
51 0.85 0.71 4.83 14794 5273 9522
52 0.87 0.70 4.77 14895 5376 9519
53 0.88 0.69 4.72 14995 5480 9515
54 0.90 0.69 4.66 15093 5583 9510
55 0.92 0.68 4.60 15191 5686 9504
56 0.93 0.67 4.55 15287 5790 9497
57 0.95 0.66 4.50 15382 5893 9489
58 0.97 0.65 4.45 15476 5996 9479
59 0.98 0.65 4.40 15568 6100 9469
OUTLET STRUCTURE SLOT
Q=CLH
Q = Discharge (cfs) 1.72
C = Weir Coefficient 3.33 (per COB Design Standards)
H = Head (ft) 1.5
L = Horizontal Length (ft) 0.28
L = Slot Width (inches) 3.4
Tc (Pre-Development) (minutes) 64
4. Calculate Rainfall Intensity(Duration =Pre-Development Tc)
i = 0.64z o.65 (10-yr Storm, Fig. 1-3, COB Design Standards)
x = storm duration (hrs) 1.07 (Tc Pre-Development)
i= rainfall intensity(in.1hr.) 0.61
5. Calculate Runoff Rate(Pre-Development)
Q = CiA
C = Rational Method Runoff Coefficient 0.2 (open land)
i = rainfall intensity(in./hr.) 0.61 (calculated above)
A= Area (acres) 14.04 (calculated above)
Q =Runoff Rate (Pre-Development) (cfs) 1.72
DETENTION POND #6
REQUIRED VOLUME
2. Calculate Area and Weighted C Factor(Post-Development)
Contributing Area C Area (ft2) C *Area
Lot 14 0.35 17989 6296
Lot15 0.35 30900 10815
Lot16 0.35 30816 10786
Lot 19 0.35 24816 8686
Sherwood ROW 1 0.74 13319 9856
Sherwood Abigail ROW 2 0.74 67847 50207
OS A 0.2 3000 600
Total 188687 97245
A =Area(acres) 4.3317
C = Weighted C Factor 0.52
3. Calculate T, (Pre-Development)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D'/2/S1/3
------------------------------
Storm
S = Slope of Basin (%) 1 'Return (yrs) Cf
C = Rational Method Runoff Coefficient 0.2 12 to 10 1
Cf= Frequency Adjustment Factor 1.1 ;11 to 25 1.1
D = Length of Basin (ft) 1512 -26 to 50 1.2
51 to 100 1.25
Tc (Pre-Development) (minutes) 64
4. Calculate Rainfall Intensity(Duration = Pre-Development Tc)
i = 0.64x o.65 (10-yr Storm, Fig. 1-3, COB Design Standards)
x= storm duration (hrs) 1.07 (Tc Pre-Development)
i=rainfall intensity(in.1hr.) 0.61
5. Calculate Runoff Rate(Pre-Development)
Q = CiA
C = Rational Method Runoff Coefficient 0.2 (open land)
i = rainfall intensity (in./hr.) 0.61 (calculated above)
A=Area (acres) 4.33 (calculated above)
Q =Runoff Rate (Pre-Development) (cfs) 0.53
6. Calculate Required Pond Volume
Total Area (acres) = 4.33 acres
Weighted C = 0.52
Discharge Rate (cfs) = 0.53 cfs (Equal to Pre-Development Runoff Rate)
Duration(min) Duration(hrs) Intensity Q�� (cfs) Runoff Release Required
(in/hi) Volume Volume Storage (ft)
48 0.80 0.74 1.65 4157 1531 3226
49 0.82 0.73 1.63 4792 1563 3228
50 0.83 0.72 1.61 4826 1595 3230
51 0.85 0.71 1.59 4859 1627 3232
52 0.87 0.70 1.57 4892 1659 3233
53 0.88 0.69 1.55 4925 1691 3234
54 0.90 0.69 1.53 4957 1723 3234
55 0.92 0.68 1.51 4989 1755 3235
56 0.93 0.67 1.49 5021 1787 3234
57 0.95 0.66 1.48 5052 1819 3233
58 0.97 0.65 1.46 5083 1850 3232
OUTLET STRUCTURE SLOT
Q=CLH"`
Q = Discharge (cfs) 0.53
C = Weir Coefficient 3.33 (per COB Design Standards)
H = Head (ft) 1.5
L = Horizontal Length (ft) 0.09
L = Slot Width (inches) 1.0
RETENTION POND #7
REQUIRED VOLUME
1. Calculate Area and Weighted C Factor
Contrihutilig Area G Area (ft') C *Area
Lot 5 0.5 49926 24963
OS H 0.2 5539 1108
Lot 13 0.5 51727 25864
Total 107192 51934
C=Weighted C Factor 0.48
3. Calculate Required Volume
Q = CIA
V=72000
C =Weighted C Factor 0.48
1 = intensity(in/hr) 0.41 (10 yr, 2hr storm)
A= Area (acres) 2.46
Q = runoff(cfs) 0.49
V= REQUIRED VOL (ft) 3520
DETENTION POND #8
TO BE CONVERTED TO DETENTION
REQUIRED VOLUME
2. Calculate Area and Weighted C Factor(Post-Development)
_Contributing Area C Area (ft2) C *Area
Block 34 East 0.5 86961 43481
Block 34 West 0.5 69209 34605
Oak Laurel ROW 14 0.72 63396 45645
Oak ROW 11 0.95 6025 5724
Oak ROW 12 0.74 12177 9011
Oak ROW 13 0.74 6850 5069
Lot 1 0.35 10734 3757
Total 255352 147291
A =Area(acres) 5.8621
C= Weighted C Factor 0.58
3. Calculate T, (Pre-Development)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D'12/S'/3
Storm
S = Slope of Basin (%) 1.9 ;Return (yrs) Cf
C = Rational Method Runoff Coefficient 0.2 :2 to 10 ill
Cf= Frequency Adjustment Factor 1.1 ;11 to 25 1.1:
D = Length of Basin (ft) 662 ;26 to 50 1.2;
51 to 100 1.25;
.---------------_-
Tc(Pre-Development) (minutes) 34
4. Calculate Rainfall Intensity(Duration =Pre-Development Tc)
i = 0.64x o.65 (10-yr Storm, Fig. 1-3, COB Design Standards)
x= storm duration (hrs) 0.57 (Tc Pre-Development)
i=rainfall intensity(in./hr.) &92
5. Calculate Runoff Rate (Pre-Development)
Q = CiA
C = Rational Method Runoff Coefficient 0.2 (open land)
i = rainfall intensity (in./hr.) 0.92 (calculated above)
A= Area (acres) 5.86 (calculated above)
Q =Runoff Rate (Pre-Development) (cfs) 1.08
6. Calculate Required Pond Volume
Total Area (acres) = 5.86 acres
Weighted C = 0.58
Discharge Rate (cfs) = 1.08 cfs (Equal to Pre-Development Runoff Rate)
Duration(min) Duration(hrs) Intensity Q.� (cfs) Runoff Release Required3
(in/hr) Volume Volume Storage W)
48 0.80 0.74 2.50 7205 3115 4090
49 0.82 0.73 2.47 7257 3180 4078
50 0.83 0.72 2.44 7309 3245 4064
51 0.85 0.71 2.41 7360 3310 4050
52 0.87 0.70 2.38 7410 3375 4035
53 0.88 0.69 2.35 74.60 3439 4020
54 0.90 0.69 2.32 7509 3504 4004
55 0.92 0.68 2.29 7557 3569 3988
5.6 0.93 0.67 2.26 7605 3634 3971
57 0.95 0.66 2.24 7652 3699 3953
58 0.97 0:65 2.21 7699 3764 3935
OUTLET STRUCTURE SLOT
Q=CLH '1
Q = Discharge (cfs) 1.08
C =Weir Coefficient 3.33 (per COB Design Standards)
H = Head (ft) 1.5
L = Horizontal Length (ft) 0.18
L =Slot Width (inches) 2.1
MANNING'S EQUATION FOR PIPE FLOW
Project: Boulder Creek Location: Detention Pond#5 18" Outlet Pipe Capacity
By: ADM Date: 4/3/2015
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 18 inches
d= 16.88 inches
Mannings Formula d n= 0.013 mannings
D 0= 57.7 degrees
Q=(1.486/n)ARh213S112
S= 0.0119 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)R'21IS112
S=slope of channel Q=V X A
n=Manning's roughness coefficient
Solution to Mannings Equation Manning's n-values
Wetted Hydraulic
Area,ft2 Perimeter,ft Radius,ft velocity ft/s flow,cfs PVC 0.013
1.72 3.96 0.44 7.16 12.33 PE(<9"dia) 0.015
PE(>12"dia) 0.02
PE(9-12"dia) 0.017
CMP 0.025
ADS N12 0.012
HCMP 0.023
Conc 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Boulder Creek Location: Detention Pond #5 18" Outlet Pipe Peak Flow
By: ADM Date: 4/3/2015
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 18 inches
d= 12.50 inches
Mannings Formula d n= 0.013 mannings
D 0= 134.3 degrees
Q=(1.486/n)ARh213St12
S= 0.0119 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh213Sv2
S=slope of channel Q=V X A
n=Manning's roughness coefficient
Solution to Mannings Equation Manning's n-values
Wetted Hydraulic
Area,ft2 Perimeter,ft Radius,ft velocity ft/s flow,cfs PVC 0.013
1.31 2.95 0.44 7.25 9.49 PE(<9"dia) 0.015
PE(>12"dia) 0.02
PE(9-12"dia) 0.017
CMP 0.025
ADS N12 0.012
HCMP 0.023
Conc 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Boulder Creek Location: Detention Pond#6 15" Outlet Pipe Capacity
By: ADM Date: 4/3/2015
Chk. 13y: Date:
Clear Data Entry
0 — - Cells
INPUT
D= 15 inches
d= 14.07 inches
Mannings Formula d \/ n 0.013 mannings
D 0= 57.7 degrees
Q=(1.486/n)ARh21IS11
S- 0.0054 slope in/in
R=A/P -- -
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh2135112
S=slope of channel Q=V X A
n=Manning's roughness coefficient
Solution to Mannings Equation Manning's n-values
Wetted Hydraulic
Area,ft2 Perimeter,ft Radius,ft velocity ft/s flow,cfs PVC 0.013
1.20 3.30 0.36 4.27 5.11 PE(<9"dia) 0.015
PE(>12"dia) 0.02
PE(9-12"dia) 0.017
CMP 0.025
ADS N12 0.012
HCMP 0.023
Conc 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Boulder Creek Location: Detention Pond #6 15" Outlet Pipe Peak Flow
By: ADM Date: 4/3/2015
Chk. Icy: Date:
Clear Data Entry
Cells
i INPUT
D= 15 inches
d= 8.10 inches
Mannings Formula d n 0.013 mannings
D 0= 170.8 degrees
Q=(1.486/n)ARh21IS112
S= 0.0054 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh21IS112
S=slope of channel Q=V X A
n=Manning's roughness coefficient
Solution to Mannings Equation Manning's n-values
Wetted Hydraulic
Area,ft2 Perimeter,ft Radius,ft velocity fUs flow,cfs PVC 0.013
0.68 2.06 0.33 3.99 2.70 PE(<9"dia) 0.015
PE(>12"dia) 0.02
PE(9-12"dia) 0.017
CMP 0.025
ADS N12 0.012
HCMPJ 0.023
Conc 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Boulder Creek Location: Detention Pond#8 15" Outlet Pipe Capacity
By: ADM Date: 4/3/2015
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 14.07 inches
Mannings Formula d n= 0.013 mannings
D 0= 57.7 degrees
Q=(1.486/n)ARh2i3S1i2
S= 0.0059 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh213SI12
S=slope of channel Q=V X A
n=Manning's roughness coefficient
Solution to Mannings Equation Manning's n-values
Wetted Hydraulic
Area,ft2 Perimeter,ft Radius,ft velocity ft/s flow,cfs PVC 0.013
1.20 3.30 0.36 4.46 5.34 PE(<9"dia) 0.015
PE(>12"dia) 0.02
PE(9-12"dia) 0.017
CMP 0.025
ADS N12 0.012
HCMP 0.023
Conc 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Boulder Creek Location: Detention Pond#8 15" Outlet Pipe Peak Flow
By: ADM Date: 4/3/2015
Chk. By: Date:
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0 Cells
INPUT
D= 15 inches
d= 11.22 inches
Mannings Formula d P n= 0.013 mannings
D 0= 120.5 degrees
Q=(1.486/n)ARh213S112
S= 0.0059 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh21IS112
S=slope of channel Q=V X A
n=Manning's roughness coefficient
Solution to Mannings Equation Manning's n-values
Wetted Hydraulic
Area,ft2 Perimeter,ft Radius,ft velocity ft/s flow,cfs PVC 0.013
0.98 2.61 0.38 4.58 4.51 PE(<9"dia) 0.015
PE(>12"dia) 0.02
PE(9-12"dia) 0.017
CMP 0.025
ADS N12 0.012
HCMP 0.023
Conc 0.013