HomeMy WebLinkAbout15 - Design Report - Westbrook - Stormwater STORMWATER MANAGEMENT
DESIGN REPORT
WESTBROOK 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
(4Qb)�.5$fi1 +A5
Project umTer: 14693
JANUARY 2015
INTRODUCTION
Westbrook Subdivision is a 63 lot residential subdivision located east of Laurel Parkway and south
of Annie Street. The 33.57-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.
STORMWATER MANAGEMENT
Design of the stormwater facilities for this project will be based on the City of Bozeman Design
Standards and Specifications Policy, March 2004 including Addendums 1 through 5.
The subdivision will be divided into separate drainage areas. A composite"C"runoff coefficient
will be 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. 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 will be
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 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
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.
Retention ponds will be used to retain stormwater as it percolates into the soil and evaporates.
Detention ponds will be used to treat stormwater prior to discharging it to Baxter Creek. Design
water depths will not exceed 1.5 feet. Retention ponds will be sized per City of Bozeman Design
Standards to handle the entire volume from the 10-year, 2-hour storm event. Detention ponds
Design Report-Page 2 of 11
will also be sized per City of Bozeman Design Standards. The pre-developed runoff rate is
calculated and a discharge structure is 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
required storage. The storm duration is increased until the maximum required storage is
calculated. Detailed calculations for the detention and retention pond volumes can be found in
Appendix D.
STORMWATER DESIGN
Stormwater runoff from the subdivision will be conveyed to one of three detention/retention
facilities. A plan view of the site highlighting the drainage areas and the stormwater features is
included in Appendix B.
The western part of the site will drain into Existing Detention Pond #1 that is located at the
southeast corner of the intersection of Laurel Parkway and Sherwood Way. This pond has an
existing outlet structure that discharges into Baxter Creek. Retention Pond #2 is a retention pond
that retains runoff from Annie Street and it will eventually be modified with the site plan for Lot 1,
Block 5 of Westbrook to be a detention pond. Detention Pond #3 is a detention pond that will
detain and release runoff from the southeast area of the site. Detention Pond #3 will discharge
treated stormwater into Baxter Creek.
RETENTION POND #2
Retention Pond#2 will retain runoff from Drainage Areas #10, #11, #12, and#13. The retention
pond is sized per City of Bozeman Design Standards where Q = CIA and V = 7200Q. The
weighted "C" factor is 0.85, the intensity is 0.41, and the total area is 1.06 acres. (See Appendix
D for detailed calculation). This requires a minimum volume of 2,669 cubic feet. Retention
Pond#2 is proposed to have a volume of 4,190 cubic feet at the 1.5 foot design water depth.
RETENTION POND #2 PIPE SIZING
The eastern part of Annie Street will drain to inlets located west of the future intersection with
Abigail Lane. A 15 inch pipe will be installed from Storm Inlet 44 on the north side of Annie
Street to Storm Inlet 43 on the south side of the street. The 15 inch pipe will drain Drainage Areas
Design Report-Page 3 of 11
#11 and #13. The time of concentration for this pipe is equal to the time of concentration of
Drainage Area#13, 3.31 minutes. At this time of concentration, the calculated peak flow rate is
1.97 cfs. A 15 inch pipe at 0.4% slope has a maximum capacity of 4.39 cfs. At the design peak
flow rate of 1.97 cfs, the velocity of the water in the pipe is 3.31 fps. The pipe from ST#4 to ST
#3 is 44 feet long so the time spent in the pipe from ST #4 to ST #3 is 0.22 minutes. (See
Appendix C for detailed calculations).
A 15 inch pipe will be installed from Storm Inlet #3 to Retention Pond #2 and will drain the
combined runoff from Drainage Area#10 and #12 as well as the pipe from ST 44 to ST#3. The
combination of these drainage areas includes a total of 1.06 acres. The time of concentration from
the furthest point in the drainage area is equal to the time of concentration of the pipe from ST#4 to
ST #3 plus the time spent in the pipe from ST #4 to ST #3. This is calculated above to be 3.53
minutes. Using this time of concentration, the peak flow rate will be 4.32 cfs. A 15 inch pipe at
0.44% slope has a maximum capacity of 4.61 cfs and at the design peak flow rate of 4.32 cfs the
velocity of the water in the pipe will be 3.98 fps and the water will flow at a depth of 12.4 inches.
The pipe will flow into Retention Pond #2 which is sized per City of Bozeman Design Standards
above. (See Appendix C for detailed calculations).
DETENTION POND #3
Detention Pond #3 will retain and release runoff from Drainage Areas #1, #2, #3, and#4. These
drainage areas combined have a total area of 9.11 acres and a composite "C" runoff coefficient of
0.44. The pre-developed runoff rate is calculated to be 1.29 cfs. (See Appendix D for detailed
calculations). The storage volume is 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 34 minutes and is equal to
4,917 cubic feet. Detention Pond #3 has a volume of 6,600 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 2.5 inches to limit the discharge to 1.29 cfs. (See Appendix D for detailed calculations).
Design Report-Page 4 of 11
DETENTION POND #3 PIPE SIZING
A 15 inch pipe will be installed from Storm Inlet#1 to Storm Inlet 42. The 15 inch pipe will drain
Drainage Areas#2 and#3. The combination of these drainage areas includes a total of 4.38 acres.
The time of concentration for this pipe is equal to the time of concentration of Drainage Area#3
which is 23.09 minutes. At this time of concentration, the calculated peak flow rate is 2.83 cfs.
A 15 inch pipe at 0.53% slope has a maximum capacity of 5.06 cfs. At the design peak flow rate
of 2.83 cfs, the velocity of the water in the pipe is 4.01 fps. The pipe from ST#1 to ST#2 is 65
feet long so the time spent in the pipe from ST#1 to ST#2 is 0.27 minutes. (See Appendix C for
detailed calculations).
An 18 inch pipe will be installed from Storm Inlet #2 to Detention Pond #3 and will drain the
combined runoff from Drainage Area 41 and #4 as well as the pipe from ST #1 to ST #2. The
combination of these drainage areas includes a total of 9.11 acres. The time of concentration from
the furthest point in the drainage area is equal to the time of concentration of Drainage Area #4
which is 23.36 minutes. Using this time of concentration,the peak flow rate will be 5.70 cfs. An
18 inch pipe at 0.51%slope has a maximum capacity of 8.07 cfs and at the design peak flow rate of
5.70 cfs the velocity of the water in the pipe will be 4.68 fps and the water will flow at a depth of
11.8 inches. The pipe will flow into Detention Pond #3 which is sized per City of Bozeman
Design Standards above. (See Appendix C for detailed calculations).
OUTLET STRUCTURE AND PIPING—DETENTION POND#3
An outlet structure and piping will be installed in the northeast corner of Detention Pond#3. The
outlet structure will be sized per City of Bozeman Design Standards and a slot width of 2.5 inches
will be used to limit the runoff to the pre-developed runoff rate. The outlet pipe will be sized as an
18 inch pipe which at the 0.53% slope has a maximum capacity of 8.23 cfs. This exceeds the 25
year design flow rate of 5.70 cfs and will adequately provide overflow capacity from the detention
pond. (See Appendix C and D for detailed calculations).
EXISTING DETENTION POND #1
Existing Detention Pond 41 will retain and release runoff from Drainage Areas#5, #6, 0, #8,#9,
Boulder Creek 0, Boulder Creek#8, Laurel Glen ST#1, Laurel Glen ST#3, and Laurel Glen ST
Design Report-Page 5 of I I
#4. These drainage areas combined have a total area of 26.65 acres and a composite "C" runoff
coefficient of 0.52. The Boulder Creek Drainage Areas are included in Appendix B. The Laurel
Glen Drainage Areas are per the original Laurel Glen stormwater design report. The existing
Laurel Glen Drainage Areas are assigned a 0.50 "C"runoff coefficient as a conservative estimate
of the actual conditions. The original design report had a composite "C" of 0.39. The
pre-developed runoff rate is calculated to be 3.29 cfs. (See Appendix D for detailed calculations).
The storage volume is 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 20,104
cubic feet. The Existing Detention Pond 41 will be reshaped to have a volume of 21,535 cubic
feet at the 1.5 foot design water depth. An existing outlet structure will be modified to limit the
discharge to the pre-developed runoff rate. The outlet pipes are sized to carry the 25 year flow as
required by the City of Bozeman Design Standards. The existing weir will be modified with a
steel plate to have a slot width of 6.5 inches to limit the discharge to 3.29 cfs. (See Appendix D
for detailed calculations).
EXISTING DETENTION POND #1 PIPE SIZING
NORTH END
On the north end of the detention pond on the future Sherwood Way that is part of Boulder Creek,
an existing 15 inch pipe is installed from Existing Storm Inlet#4 to Existing Storm Inlet#5. The
15 inch pipe will drain Boulder Creek Drainage Area#8. This drainage area includes a total of
0.28 acres. The time of concentration for this pipe is equal to the time of concentration of Boulder
Creek Drainage Area#8 which is 6.33 minutes. At this time of concentration,the calculated peak
flow rate is 0.70 cfs. A 15 inch pipe at 0.09% slope has a maximum capacity of 2.08 cfs. At the
design peak flow rate of 0.70 cfs,the velocity of the water in the pipe is 1.46 fps. At this slope the
velocity of the water doesn't meet City of Bozeman Design Standards and this pipe will have to be
removed and replaced with the construction of Boulder Creek to meet the 3 fps velocity
requirement. The pipe from EX#4 to EX#5 is 32 feet long so the time spent in the pipe from EX
#4 to EX #5 is 0.37 minutes. (See Appendix C for detailed calculations).
An existing 15 inch pipe is installed from Existing Storm Inlet #5 to Existing Detention Pond #1
Design Report-Page 6 of']I
and will drain the combined runoff from Boulder Creek Drainage Area 47 and the pipe from EX#4
to EX #5. The combination of these drainage areas includes a total of 0.77 acres. The time of
concentration from the furthest point in the drainage area is equal to the time of concentration of
Boulder Creek Drainage Area #7 which is 9.31 minutes. Using this time of concentration, the
peak flow rate will be 1.57 cfs. A 15 inch pipe at 0.42%slope has a maximum capacity of4.50 cfs
and at the design peak flow rate of 1.57 cfs the velocity of the water in the pipe will be 3.15 fps and
the water will flow at a depth of 6.3 inches. The pipe will flow into Existing Detention Pond #1
which is sized per City of Bozeman Design Standards above. (See Appendix C for detailed
calculations).
SOUTH END
Two new inlets will be cut into the existing curb along Laurel Parkway to ensure the curb flow
capacity is not exceeded. These new inlets will be piped in the boulevard to minimize the impact
to the existing street. The new pipe will connect to the existing inlet located south of the
intersection of Laurel Parkway and Annie Street and will travel through the existing stonnwater
system to the Existing Detention Pond #1. Pipe size calculations are given below and detailed
calculations are provided in Appendix C that take into account the new flows from Westbrook
Subdivision as well as the existing flows from Laurel Glen Subdivision.
A 15 inch pipe will be installed from Storm Inlet#3A to Storm Manhole#4. The 15 inch pipe will
drain Drainage Area #5. This drainage area includes a total of 4.18 acres. The time of
concentration for this pipe is equal to the time of concentration of Drainage Area#5 which is 18.43
minutes. At this time of concentration, the calculated peak flow rate is 3.56 cfs. A 15 inch pipe
at 0.40% slope has a maximum capacity of 4.39 cfs. At the design peak flow rate of 3.56 cfs, the
velocity of the water in the pipe is 3.75 fps. The pipe from ST 43A to ST#4 is 5 feet long so the
time spent in the pipe from ST #3A to ST #4 is 0.02 minutes. (See Appendix C for detailed
calculations).
A 15 inch pipe will be installed from Storm Manhole #4 to Storm Manhole 43. The 15 inch pipe
will drain runoff from the pipe from ST#3A to ST#4. This drainage area includes a total of 4.18
acres. The time of concentration for this pipe is equal to the time of concentration of Drainage
Design Report-Page 7 of 11
Area #5 plus the time spent in the pipe from ST #3A to ST #4 which is 18.45 minutes. At this
time of concentration,the calculated peak flow rate is 3.55 cfs. A 15 inch pipe at 1.05%slope has
a maximum capacity of 7.12 cfs. At the design peak flow rate of 3.55 cfs, the velocity of the
water in the pipe is 5.48 fps. The pipe from ST#4 to ST #3 is 170 feet long so the time spent in
the pipe from ST#4 to ST#3 is 0.52 minutes. (See Appendix C for detailed calculations).
A 15 inch pipe will be installed from Storm Manhole #3 to Storm Manhole#2. The 15 inch pipe
will drain runoff from the pipe from ST #4 to ST #3. This drainage area includes a total of 4.18
acres. The time of concentration for this pipe is equal to the time of concentration of the pipe
from ST #3A to ST #4 plus the time spent in the pipe from MH #4 to MH #3 which is 18.97
minutes. At this time of concentration, the calculated peak flow rate is 3.49 cfs. A 15 inch pipe
at 0.91% slope has a maximum capacity of 6.63 cfs. At the design peak flow rate of 3.49 cfs, the
velocity of the water in the pipe is 5.54 fps. The pipe from ST#3 to ST#2 is 97 feet long so the
time spent in the pipe from ST 43 to ST #4 is 0.29 minutes. (See Appendix C for detailed
calculations).
A 15 inch pipe will be installed from Storm Inlet#2A to Storm Manhole#2. The 15 inch pipe will
drain Drainage Area #6. This drainage area includes a total of 3.29 acres. The time of
concentration for this pipe is equal to the time of concentration of Drainage Area#6 which is 23.68
minutes. At this time of concentration, the calculated peak flow rate is 2.22 cfs. A 15 inch pipe
at 0.60% slope has a maximum capacity of 5.38 cfs. At the design peak flow rate of 2.22 cfs, the
velocity of the water in the pipe is 3.96 fps. The pipe from ST#2A to MH#2 is 5 feet long so the
time spent in the pipe from ST #2A to MH #2 is 0.02 minutes. (See Appendix C for detailed
calculations).
A 15 inch pipe will be installed from Storm Manhole #2 to Storm Manhole#1. The 15 inch pipe
will drain runoff from pipe ST#2A to SM#2 and from pipe SM#3 to SM#2. This drainage area
includes a. total of 7.46 acres. The time of concentration for this pipe is equal to the time of
concentration of Drainage Area#6 plus the time spent in the pipe from ST#2A to SM#2 which is
23.70 minutes. At this time of concentration,the calculated peak flow rate is 5.24 cfs. A 15 inch
pipe at 0.82%slope has a maximum capacity of 6.29 cfs. At the design peak flow rate of 5.24 cfs,
Design Report-Page 8 of 11
the velocity of the water in the pipe is 5.39 fps. The pipe from MH 42 to MH #1 is 332 feet long
so the time spent in the pipe from MH#2 to MH#1 is 1.03 minutes. (See Appendix C for detailed
calculations).
A 15 inch pipe will be installed from Storm Manhole #1 to Existing Inlet #1. The 15 inch pipe
will drain runoff from pipe MH #2 to MH #1. This drainage area includes a total of 7.46 acres.
The time of concentration for this pipe is equal to the time of concentration of the pipe from MH#2
to MH #1 plus the time spent in the pipe from MH#2 to MH #1 which is 24.73 minutes. At this
time of concentration,the calculated peak flow rate is 5.10 cfs. A 15 inch pipe at 5.20%slope has
a maximum capacity of 15.85 cfs. At the design peak flow rate of 5.10 cfs, the velocity of the
water in the pipe is 10.92 fps. The pipe from MH#1 to EX ST#1 is 5 feet long so the time spent
in the pipe from MH#1 to EX ST#1 is 0.01minutes. (See Appendix C for detailed calculations).
An existing 15 inch pipe is installed from Existing Inlet#1 to Existing Manhole#2. The pitch on
the existing line is not adequate to drain the flows from ST MH#1 to Existing Inlet#1 and the flow
from the Existing Pipe #5 detailed in the original Laurel Glen stormwater design report to have a
flow of 2.95 cfs. This 15 inch pipe will be removed and replaced with a new 15 inch pipe that will
maintain the same invert at Existing Inlet #1 and will match the outflow invert elevation in
Existing Manhole#2. The combination of these drainage areas includes a total of 7.46 acres plus
Storm #1 Area from Laurel Glen of 6.77 acres for a total of 14.23 acres. The time of
concentration for this pipe is equal to the time of concentration of the Existing Pipe #5 calculated
in the original Laurel Glen storm design to be 27.00 minutes. At this time of concentration, the
calculated peak flow rate is 7.77 cfs. A 15 inch pipe at 2.78% slope has a maximum capacity of
11.63 cfs. At the design peak flow rate of 7.77 cfs,the velocity of the water in the pipe is 9.58 fps.
The pipe from EX INLET #1 to EX MH #2 is 95 feet long so the time spent in the pipe from EX
INLET#1 to EX MH#2 is 0.17 minutes. (See Appendix C for detailed calculations).
An existing 24 inch pipe is installed from Existing Manhole#2 to Existing Inlet#3. This pipe will
drain the water from the pipe from EX INLET#1 TO EX MH#2 as well as the water from Existing
Pipe #6 from the original Laurel Glen stormwater design report. The combination of these
drainage areas includes a total of 7.46 acres plus the Storm#1 area from Laurel Glen of 6.77 acres
Design Report-Page 9 of 11
plus the Storm#3 area of 9.27 acres and Storm 44 area of 1.35 acres for a total of 24.85 acres. The
time of concentration for this pipe is equal to the time of concentration of the pipe from EX INLET
#1 to EX MH 42 plus the time spent in the pipe. This is calculated above to be 27.17 minutes.
The composition of the Laurel Glen drainage areas is not known, and therefore the peak flow for a
different time of concentration cannot be determined. To be conservative,the peak flows for each
existing pipe section is added to the flows generated by Westbrook. This is a conservative
assumption because as time of concentration increases while the water passes through the
stormwater system, the intensity decreases and the peak flow is reduced. At this time of
concentration, the calculated peak flow rate is 15.61 cfs. A 24 inch pipe at 0.53% slope has a
maximum capacity of 17.72 cfs. At the design peak flow rate of 15.61 cfs, the velocity of the
water in the pipe is 5.96 fps. The pipe from EX MH #2 to EX IN #3 is 89 feet long so the time
spent in the pipe from EX MH #2 to EX IN #3 is 0.25 minutes. (See Appendix C for detailed
calculations).
An existing 24 inch pipe is installed from Existing Inlet #3 to Existing Inlet 44. This pipe will
drain the water from the pipe from EX MH #2 to EX IN #3 as well as the water from Drainage
Area#7 and Drainage Area#8. The combination of these drainage areas includes a total of 25.40
acres. The time of concentration for this pipe is equal to the time of concentration of the pipe
from EX MH#2 to EX IN#3 plus the time spent in the pipe. This is calculated above to be 27.42
minutes. At this time of concentration,the calculated peak flow rate is 16.14 cfs. A 24 inch pipe
at 1.10% slope has a maximum capacity of 25.52 cfs. At the design peak flow rate of 16.14 cfs,
the velocity of the water in the pipe is 8.12 fps. The pipe from EX IN #3 to EX IN #4 is 47 feet
long so the time spent in the pipe from EX IN #3 to EX IN #4 is 0.10 minutes. (See Appendix C
for detailed calculations).
An existing 24 inch pipe is installed from Existing Inlet #4 to Existing Detention Pond #1. This
pipe will drain the water from the pipe from EX IN #3 to EX IN #4 as well as the water from
Drainage Area#9. The combination of these drainage areas includes a total of 25.61 acres. The
time of concentration for this pipe is equal to the time of concentration of the pipe EX IN#3 to EX
IN #4 plus the time spent in the pipe. This is calculated above to be 27.52 minutes. At this time
of concentration, the calculated peak flow rate is 16.39 cfs. A 24 inch pipe at 0.51% slope has a
Design Report-Page 10 of 11
maximum capacity of 17.38 cfs. At the design peak flow rate of 16.39 cfs, the velocity of the
water in the pipe is 5.86 fps. The pipe from EX IN#4 to EX POND#1 is 216 feet long so the time
spent in the pipe from EX IN 44 to EX POND #1 is 0.61 minutes. (See Appendix C for detailed
calculations).
OUTLET STRUCTURE AND PIPING—EXISTING DETENTION POND #1
Existing Detention Pond#1 has an existing outlet structure and piping. The existing structure will
be modified to narrow the slot to 6.5 inches by bolting a ''/z inch thick galvanized steel plate to the
weir structure. The existing dual 15 inch diameter outlet pipes are 61 feet long and sloped at
3.79%. At this slope the outlet pipes have a maximum capacity of 27.06 cfs. This is well over
the 25 year flow rate of 17.96 cfs and will adequately provide overflow capacity from the detention
pond. (See Appendix C and D for detailed calculations).
Design Report-Page 11 of 11
LEGEND
E%IsnNG seor ELEvama4 /I _._._._— MARK A.
(0. No.9578E5
zf,OD.DO) PRovosEo swT ELEvaTDN
EXSDNG PoWER BO% I \$�j RfO1�9�tCA,IE'��
IX6liNC TEIEPwNE BDX (` e4lET 1 ,!f l4��
EX6DNG ELECTRIC WX B"� � BC 4 \ w ~
EX6TING SANRART SEWER MANHOLE \
A Sheet 1 of f
EXISDND_DART SEWER CLfNroUT
IXISDND_E HYpRNR BC 07
EX TING WATER VALVE
IX6i1NG CURD SLOP ' / ; D(VOM NLET
EKGDNG POWER POLE 1 O \\ ')PD, 4
.' TING LID i POLE ) - Il �'\ (�d
I
� 5
® PROPOSED ED STORM DRNSTORM INLET ' \ \�' kO\•P�/ \ \ ce
PROPOSN WOLE
® PROPMEo SANDARTFc I
5C]YER MNADLE ' \ \ C Q
O�C PROPO5E0ED CLFANOUT ' �i .. , gg
PROPMSNNTPRTWATER VASEWERVE W [}
® PROPOSED CURB STOP �`' \
H
PROPMEo{tRE Hrwwn ..:I-. �. � /� soau wLET 4(4e�)51A)434.38(n.3ar)
OS
.®1 PROPED WATER WELL ;':;. ,, ' ,I g J ,bi
R OVT
yI PROwSEo LKMT POLE •` -.t. IX INLET 4 / (S):4)4B.el(IS) '.
PROPERTY BOUNCN4Y UNE - \�Y~ 'i.$ Rd9 .32# -.�a) V� F]-A--# / ...\
:1FUT1DMG I—ERTT"NE E%SDMH 2(44•)s.11a6969(28.62R) \ \ \-/L/l
—SEteAD%uNERIN:4752 el
EDGE FL.N(5):474
ID(w) -- \.
- OF WETVND
._ ___.EASEMENT UNE EX 4"""2 _
EXISTING FENCE WM J5295 e4J OUT(N)!4]46.]2
INV�O (NE) ]].10 INV (W)m)4e 12
----IX6TING OVERHEAD ELECTRIC UNE (SW) )4)fO \ W
—NO UNDERGROUND ELECTRIC LINE ]V kfv IN(SE) J 955 \ �
IXt3TNC C15 UNE E%INLET I _
-'-- UNO PHONE UNE RE) 4)532)
EXISTING UNDERGRO 1
F%ISDNG OVFAHCAD PHONE LINE
OUT( 4]498J �� \ \ STORM IALEi 3 48" STA 13(21.92-R)
A RROPMED WATER..ICE RIM D:IN I
4753O1 II \ \ \ // {�1. ( � 85(IT))
8"N—PwPMED T WATER AWN p1V OUT(N)-4749.74 4
a 5—PROPOSED 4 SPN11Ntt SEWER SEI CE I.1N(W)-4749)4
e' STA
PROPOSED 6'SNtlTNiT SEWER MNN GOMH 1 4 IOa)518(]355'R)
R 4)
4T—PROPOSED STORM SEWER R IN(5):4)984 —PON \ \
--u.,c ---PROPOSED UNDERGROUND ELECTRIC UNE R OUT(W):f)49e (15) ) _.. \
.- — —PROPOSED SWALE/RETENDON POND CONTOUR tO0 Saale O Feet T� ' .:..1 / `))\DEtO.T%H F�.g11�ET,I4'e')STA 1 t 5)(O.O1'L)
PROPMEU CVPD ANo GUTTER I., / M \4(NE):4p.,//.O IE)
3C C JO L / STORM INLET 2(4T)/iA Sa9,M(..A,)
i L
Scale lTl NeLere SOMM 2(46 STA J 42 ST(35]B'R ' 1 / R IN(SW)A)52.59 !A') e�
COTILOMT Intervals: F F..t / / FL OUT(N)4]5L5 8') ,./�
.• R m t5) )52),(,r) DA 01 /
R IN(W):4)52.)1(IT)
ITT
STORM FVIET 2A 4e')STA OUT
]a42.6O
R (E)4J52]4(15)
STORM INLET 1 111") 4a6. (0,00')
e
SOMH 3(46)STA 6 (SO
FR x4(s): DA 02 IR.�(NE):4)52.94
s
L OUT N)4 ') 11
I O
DA A
SONH4(4S)TA 4,
R e4 (N):4 5 39 (I R OUT
SroaM INLET sa(4T srA 4.1e.M(zs B )
R OlR(E):4)35 t1
-.-0.. _
UA
Z8
0jj� 0
DA 05
) 1 t 1
- J/)
DA „4
leette Date:1-19-15
-DRAINAGE MAP D
AI
oA) swi:r=too
114691
DRAINAGE AREA# 1
Contributing Area C Area (ft) C * Area Composite ROW
ROW 0.7375 10631 784o ((0.95*43)+(0.2*17))/60
OS/Park 0.2 0 0 0.7375
Lots 0.35 34701 12145
Total 45332 "1'9085".1
C = Weighted C Factor 0.44
A=Area(acres) 1.04
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 0.35 2 to 10 1
Cf=Frequency Adjustment Factor 1,1 I 1 to 25 1.1
D=Length of Basin(ft) 110 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) _ 17.67:
Te Gutter Flow
Tc=L/V/60
V= (1.486/n)R2/3 S 11
n= Mannings Coefficient 0:013
R=Hydraulic Radius A/P (ft) 013 (015'below top of curb)
S = slope (ft/ft) 0.005
L = length of gutter(ft) 310
V=mean velocity(ft/s) 2.12
Tc Gutter Flow(minutes)
Tc Total (Overland + Gutter) = 20: 0
Q = CIA
C = Weighted C Factor ` 0.44 (calculated above)
I=0.78 Tc o.64(in/hr) 1S7
Drainage Area#1
A= area (acres) 1.04
Qrequired (Cfs) = 0.72;
Provided Gutter Capacity (flowing at 0.15' below ton of curb)
Q = (1.486/n)AR"'S"'
n = Mannings Coefficient 0.013
A =area(ft2) 1. 4
P=wetted perimeter(ft) 9; 3
R=Hydraulic Radius A/P (ft) 0.13
............................
S = slope (ft/ft) 0.005
Qprovided (CfS) = 1.63
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#1
DRAINAGE AREA # 2
Contributing Area C Area(ft 2) C * Area Composite ROW
ROW 0.7375 9405 6936 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3309 662 0.7375
Lots 0.35 25845 ;,9,046�
Total 38559 1:6643:3'
C = Weighted C Factor 0.43
A=Area(acres) 0.89;
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 0.35 2 to 10 1
C f=Frequency Adjustment Factor 1:1 I 1 to 25 1.1
D =Length of Basin (ft) 110 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes)
Tc Gutter Flow (West on Babcock)
Tc =LN160
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) 0.005
L=length of gutter(ft) 285
V=mean velocity(ft/s) 2:1
Tc Gutter Flow(minutes)
Tc Total (Overland + Gutter)
Q = CIA
C =Weighted C Factor 0.43�(calculated above)
I= 0.78 Tc 0.64(in/hr)
Drainage Area#2
A=area (acres) 0.89,
Qrequired (efs)
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)ARZi3S"
n=Mannings Coefficient . I'6013'
A = area(ft)
P =wetted perimeter(ft) 9.23'
R=Hydraulic Radius A/P (ft) 0.13`
S = slope (ft/ft) 0.005
Qprovided (cfs) = 2.6-3
GUTTER HASADEQUATE CAPACITY
Drainage Area#2
DRAINAGE AREA # 3
Contributing Area C Area(ft 2) C * Area Composite ROW
ROW 0.7375 44648 32928, ((0.95*43)+(0.2*17))/60
OS/Park 0.2 9905 1981 0.7375
Lots 0.35 97865 34253-
Total 152418 _6916T.7'
C = Weighted C Factor OA5
A =Area(acres) 3.50
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 035 2 to 10 1
Cf=Frequency Adjustment Factor 1 1 11 to 25 1.1
D = Length of Basin(ft) 110 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 17:67''
Tc Gutter Flow (West on Babcock)
Tc=L/V/60
V=(1.486/n)R2/3 S1/2
n=Mannings Coefficient 0:fl13
R=Hydraulic Radius A/P (ft) 0.13 (0.15'below top of curb)
S = slope (ft/ft) 0.008
L = length of gutter(ft) 845
V=mean velocity(ft/s) �Zb0
Tc Gutter Flow(minutes)_ 5:42.
Tc Total (Overland+ Gutter)
Q = CIA
C =Weighted C Factor45 (calculated above)
I= 0.78 Tc 0'64(in/hr) 1g44'
Drainage Area#3
A= area (acres) 3.50'
Qrequired (efs) — 2.2&
Provided Gutter Capacity (flowing at 0.15' below ton of curb)
Q= (1.486/n)AR'/3S1/1
n=Mannings Coefficient 0013
A= area(ftZ) 1.24'
P=wetted perimeter(ft) 9.23
R=Hydraulic Radius A/P (ft)
S =slope (ft/ft) 0.005
Qprovided WS) = 2.63`
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#3
DRAINAGE AREA # 4
Contributing Area C Area(ft) C * Area Composite ROW
ROW 0.7375 32067 � D{49 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3389 618 0.7375
Lots 0.35 125284 43849'
Total 160740 68176.6
C = Weighted C Factor 0,412
A=Area(acres) 369'
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 0.35' 2 to 10 1
Cf=Frequency Adjustment Factor 1:1 I I to 25 1.1
D =Length of Basin(ft) 110 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) _ 1 7.67
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) 0.13 (0.15' below top of curb)
S = slope (ft/ft) 0.008
L= length of gutter(ft) 983
V=mean velocity(ft/s) 2:60
Tc Gutter Flow(minutes)
Tc Total (Overland+ Gutter)
Q= CIA
C = Weighted C Factor0,42 (calculated above)
I=0.78 Tc-0 64(in/hr) 1:.40
Drainage Area#4
A = area(acres) 3.69
[required (efS)
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q =(1.486/n)AR"S"
n= Mannings Coefficient 0.013`
A =area(ft2) 1.24;
P =wetted perimeter(ft) 9.23
R= Hydraulic Radius A/P (ft)
S = slope (ft/ft) 0.005
Qprovided (CfS) = 2.63
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#4
DRAINAGE AREA # 5
Contributing Area C Area(ft2) C * Area Composite ROW
ROW 0.7375 38869 2866,E ((0.95*43)+(0.2*17))/60
OS/Park 0.2 0 0" 0.7375
Lots 0.35 107223 37528
Laurel Pkwy ROW 0.81 21200 , ` 17172'
Durston ROW 0.68 14592 , 9923'!
Total 181'884, ,=, 932881
C = Weighted C Factor 0.54'
A=Area(acres) 418
Required Gutter/Pine Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CCr)D1/2/S1/3
Storm
S = Slope of Basin (%) 1 Return Cf
C =Rational Method Runoff Coefficient 0.35i 2 to 10 1
Cf=Frequency Adjustment Factor 1.1 11 to 25 1.1
D = Length of Basin(ft) 120 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 14.65
Tc Gutter Flaw (West on Babcock)
Tc=L/V/60
V = (1.486/n)R2/3 S 1/2
n=Mannings Coefficient 0.013
R=Hydraulic Radius A/P (ft) 0:13,(0.15' below top of curb)
S = slope (ft/ft) 0.010
L= length of gutter(ft) 680
V =mean velocity(ft/s) 3.00!
Tc Gutter Flow(minutes) = 3 38
Tc Total (Overland+ Gutter) = 18.43
Q = CIA
Drainage Area#5
C = Weighted C Factor 0.51 (calculated above)
I= 0.78 Tc-0.64(in/hr)
A = area(acres)
Qrequired (Cfs)
Provided Gutter Capacity (flowing at 0.15' below ton of curb)
Q = (1.486/n)AR"'S"
n=Mannings Coefficient O.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) 0.01
Qprovided (Cfs)
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#5
DRAINAGE AREA# 6
Contributing Area C Area(ft 2) C * Area Composite ROW
ROW 0.7375 16331 12044 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3300 b60 0.7375
Lots 0.35 96575 33801
Laurel Pkwy ROW 0.81 26918 21804i
Total 14314 68309.E
C = Weighted C Factor 048
A=Area(acres) 329'
Required Gutter/Pine Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CC)D1/2/S113
Storm
S = Slope of Basin (%) 1 Return Cf
C = Rational Method Runoff Coefficient 0.35 2 to 10 1
Cf=Frequency Adjustment Factor 1>1 1 I to 25 1.1
D =Length of Basin(ft) 220 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 19.83
Tc Gutter Flow (West on Babcock)
Tc=LN160
V =(1.486/n)R2i3 Slit
n=Mannings Coefficient 0:013
R= Hydraulic Radius A/P (ft) 0,13 (0.15' below top of curb)
S = slope (ft/ft) 0.010
L =length of gutter(ft) 693
V=mean velocity(ft/s) 3;00
Tc Gutter Flow(minutes)_ ::3:8;5
Tc Total (Overland+ Gutter)
Q = CIA
C = Weighted C Factor 0.48 (calculated above)
Drainage Area#6
I= 0.78 Tc-°.64(in/hr) 1.41
A = area (acres) 1. 9
Qrequired (CfS) _ 212
Provided Gutter Capacity (flowing at 0.15' below ton of curb)
Q= (1.486/n)AR"S"
n=Mannings Coefficient fl,013;'
A =area(ft2) 1.24
P =wetted perimeter(ft) 9:2 :
R= Hydraulic Radius A/P (ft) 0.13'
S = slope (ft/ft) 0.01
Qprovided WS) _ 1,72
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#6
DRAINAGE AREA # 7
Contributing Area C Area(ft) C * Area
Road 0.95 7485 ,7111'
Boulevard 0.2 1969 .394
Total 9454� �7505
C = Weighted C Factor
A = Area(acres) 0�2''
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D"/S1/3
Storm
S = Slope of Basin(%) 0.5 Return Cf
C =Rational Method Runoff Coefficient 035 2 to 10 1
Cf=Frequency Adjustment Factor 1:1 11 to 25 1.1
D = Length of Basin(ft) 20 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes)_ 7.53
Tc Gutter Flow (West on Babcock)
Tc= L/V/60
V = (1.486/n)R2/3 S11
n= Mannings Coefficient 0.013'
R=Hydraulic Radius A/P (ft) ` 0.13 (0.15' below top of curb)
S = slope (ft/ft) 0.010
L=length of gutter(ft) _ 141
V =mean velocity(ft/s) 3.00
Te Gutter Flow(minutes) = 0.78
Tc Total (Overland+ Gutter)= 832
Q = CIA
C = Weighted C Factor 0,79 (calculated above)
1 = 0.78 Tc-0 64(in/hr) 2.36
A = area(acres) 02
Drainage Area#7
Qrequired (Cfs) = 0.48
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR"S"
n= Mannings Coefficient 0.013
A = area(ft2) : �}
P = wetted perimeter(ft) 9:23
R=Hydraulic Radius A/P (ft)
S = slope (ft/ft) 0.01
Qprovided WS) = 3.72'
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#7
DRAINAGE AREA # 8
Contributing Area C Area(ft 2) C * Area
Road 0.95 11302 10737
Boulevard 0.2 2963 593
Total -14265 11330
C = Weighted C Factor 0.79
A =Area(acres) 033
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D"/S1/3
Storm
S = Slope of Basin(%) 1 Return Cf
C =Rational Method Runoff Coefficient 0:35' 2 to 10 1
C f=Frequency Adjustment Factor 1.1 11 to 25 1.1
D= Length of Basin(ft) 20 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 S11
n=Mannings Coefficient 0:013
R=Hydraulic Radius A/P (ft) 0h1�3 (0.15' below top of curb)
S = slope (ft/ft) 0.005
L= length of gutter(ft) 390
V = mean velocity(ft/s)
Tc Gutter Flow(minutes)
Tc Total (Overland+ Gutter) = 905
Q= CIA
C =Weighted C Factor 0.79-(calculated above)
I=0.78 Tc-O 64(in/hr) 2;
A= area(acres) 033
Drainage Area#8
Qrequired (Cfs) = 0.68
Provided Gutter Capacity (flowing at 0.15' below ton of curb)
Q = (1.486/n)AR"S"
n=Mannings Coefficient 0.013
A= area(ft) 1.24'`
P =wetted perimeter(ft) 9"21
R= Hydraulic Radius A/P (ft) 0:1
S = slope (ft/ft) 0.01
Qprovided WS) _ 3.72;
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#8
DRAINAGE AREA # 9
Contributing Area C Area(ft2) C * Area
Road 0.95 9208 8748
Boulevard 0.2 0 0'
Total >9208 8748
C = Weighted C Factor 0.95
A=Area(acres) 0.21
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D"/S1/3
Storm
S = Slope of Basin (%) 1 Return Cf
C =Rational Method Runoff Coefficient 0.351 2 to 10 1
Cf=Frequency Adjustment Factor 1.1 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) = 0;00
Tc Gutter Flow (West on Babcock)
Tc=L/V/60
V = (1.486/n)R213 S1/2
n=Mannings Coefficient 04013
R=Hydraulic Radius A/P (ft) 0.13 (0.15' below top of curb)
S = slope (ft/ft) 0.005
L= length of gutter (ft) 390
V =mean velocity (ft/s) 2.12;
Tc Gutter Flow(minutes)
Tc Total (Overland + Gutter) _ 107
Q = CIA
C = Weighted C Factor >0.95%(calculated above)
I=0.78 Tc 064(in/hr) 5:23
A= area(acres) 0.21
Drainage Area#9
Qrequired (efs) = 1.05•
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR"S"
n =Mannings Coefficient 0.013'
A= area(ft) „ ).24
P=wetted perimeter(ft) .23
R=Hydraulic Radius A/P (ft) 013'
S = slope (ft/ft) 0.01
Qprovided WS)
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#9
DRAINAGE AREA# 1.0
Contributing Area C Area(ft 2) C * Area
Road 0.95 9819 9328:
Boulevard 0.2 2658 532
Total 12477 9860
C = Weighted C Factor 0 79
A=Area(acres) 029
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc = 1.87 (1.1-CC)D"/S1/3
Storm
S = Slope of Basin (%) 1 Return Cf
C =Rational Method Runoff Coefficient 0 35 2 to 10 1
C f=Frequency Adjustment Factor 1 ), 11 to 25 1.1
D =Length of Basin (ft) 16 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 Q13
R=Hydraulic Radius A/P (ft) 0:I (0.15' below top of curb)
S= slope (ft/ft) 0.005
L= length of gutter(ft) 340
V=mean velocity(ft/s) 21
Tc Gutter Flow(minutes)
Tc Total (Overland+ Gutter)
Q= CIA
C = Weighted C Factor 0 7 !'(calculated above)
1 =0.78 Tc 0 64(in/hr) 2 83
A= area(acres) 0 2 `
Drainage Area#10
Qrequired (CfS) = 0.64
Provided Gutter Capacity (flowing at 0.15' below ton of curb)
Q = (1.486/n)AR"SU2
n=Mannings Coefficient Ob 1
A= area(ft2) 124`
P = wetted perimeter(ft) 9
R=Hydraulic Radius A/P (ft)
S = slope (ft/ft) 0.01
Qprovided (CfS) _ .`172
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#10
DRAINAGE AREA # I I
Contributing Area C Area(ft) C * Area
Road 0.95 8063 7660'
Boulevard 0.2 0 : �Q
Total ,8463
C = Weighted C Factor 095
A=Area(acres) 019
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D"/S1/3
Storm
S = Slope of Basin(%) 1 Return Cf
C= Rational Method Runoff Coefficient .035 2 to 10 1
Cf= Frequency Adjustment Factor 1.,1 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)
Tc Gutter Flow (West on Babcock)
Tc=LN160
V = (1.486/n)R" S"
n=Mannings Coefficient 0,�013
R=Hydraulic Radius A/P (ft) 013 (0.15`below top of curb)
S = slope (ft/ft) 0.005
L= length of gutter(ft) 340
V=mean velocity(ft/s) 2.42
Tc Gutter Flow(minutes)_
Tc Total (Overland+ Gutter) = 2'67:
Q = CIA
C = Weighted C Factor 0 95„(calculated above)
I = 0.78 Tc- 64(in/hr) 5 71
A = area(acres) 0 1 .
Drainage Area#11
Qrequired (CfS)
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR"S"
n=Mannings Coefficient 0 b'13'
A= area(ft2) ).
P=wetted perimeter(ft) 93
R=Hydraulic Radius A/P (ft)
S = slope (ft/ft) 0.01
Qprovided (CfS) = 3.72'
GUTTER HASADEQUATE CAPACITY
Drainage Area#11
DRAINAGE AREA# 12
Contributing Area C Area(ft 2) C * Area
Road 0.95 12254 1�61
Boulevard 0.2 3314
Total155682304
C= Weighted C Factor 079
A=Area(acres) =0:3`6'
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(%} 1 Return Cf
C =Rational Method Runoff Coefficient0;35 2 to 10 1
C f=Frequency Adjustment Factor 11 to 25 1.1
D =Length of Basin (ft) 16 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)R2i3 S12
n=Mannings Coefficient 0'0
R=Hydraulic Radius A/P (ft) 0;,13 (0.15'below top of curb)
S = slope (ft/ft) 0.005
L= length of gutter(ft) 421
V=mean velocity (ft/s) 212_
Tc Gutter Flow(minutes)
Tc Total (Overland+ Gutter)= 8
Q = CIA
C = Weighted C Factor 0 79'(calculated above)
1 = 0.78 Tc 0.64(in/hr) 2 69
A=area(acres) fl.3
Drainage Area#12
Qrequired (CfS) = 0.76'
Provided Gutter Capacity (flowing at 0.15' below ton of curb)
Q = (1.486/n)AR"S"
n=Mannings Coefficient
A=area(ft2) 124,
P =wetted perimeter(ft) �� 93
R=Hydraulic Radius A/P (ft)
S = slope (ft/ft) 0.01�
Qprovided WS)
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#12
DRAINAGE AREA # 13
Contributing Area C Area(ft 2) C * Area
Road 0.95 10063 :, .` �9,
Boulevard 0.2 0 �0
Total �956�0:
C = Weighted C Factor
A=Area(acres) :Q23
Required Gutter/Pipe Capacity (25-yr Storm)
Tc Overland Flow
Tc= 1.87 (1.1-CCf)D"/SI/3
Storm
S = Slope of Basin(%) 1 Return Cf
C=Rational Method Runoff Coefficient 03 2 to 10 1
Cf= Frequency Adjustment Factor la 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) _ 0,00,
Tc Gutter Flow (West on Babcock)
Tc=L/V/60
V = (1.486/n)R21 S11
n=Mannings Coefficient 0013
R=Hydraulic Radius A/P (ft) 0 13.(0.15' below top of curb)
S = slope (ft/ft) 0.005
L= length of gutter(ft) 421
V=mean velocity(ft/s) 1
Tc Gutter Flow(minutes)
Tc Total (Overland+Gutter)
Q= CIA
C= Weighted C Factor 0 (calculated above)
1=0.78 Tc-0.64(in/hr) 4 98r
A=area(acres) ; 0, 3
Drainage Area#13
Qrequired (cfs) = LO,9.
Provided Gutter Capacity (flowing at 0.15' below top of curb)
Q = (1.486/n)AR"S"
n= Mannings Coefficient
A=area
P = wetted perimeter(ft) 923
R=Hydraulic Radius A/P (ft) 0.13
S = slope (ft/ft) 0.01
Qprovided WS) _ 172
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#13
DRAINAGE AREA # BC 7
Contributing Area C Area (ft2) C * Area Sherwood Composite ROW
Sherwood ROW 0.7625 12150 .9264 ((0.95*45)+(0.2*15))/60
Laurel Pkwy ROW 0.81 21500 17415'
Total 33650 26679` 0.7625
C = Weighted C Factor 0.79i
A=Area(acres) 0 77
Required Gutter/Pipe Capacity (25-yr Storm)
Te Overland Flow
Tc= 1.87 (1.1-CCf)D1/2/S1/3
Storm
S = Slope of Basin (%) 1 Return Cf
C =Rational Method Runoff Coefficient 0.35 2 to 10 1
C f=Frequency Adjustment Factor 1.11 11 to 25 1.1
D =Length of Basin (ft) 13.5 26 to 50 1.2
51 to 100 1.25
Tc Overland Flow(minutes) = 4.91
Tc Gutter Flow (West on Babcock)
Tc =L/V/60
V = (1.486/n)R2/1 S12
n= Mannings Coefficient 0.013
R= Hydraulic Radius A/P (ft) 0.13 (0.15' below top of curb)
S = slope (ft/ft) 0.005
L=length of gutter (ft) 560
V =mean velocity(ft/s) 2.12
Tc Gutter Flow(minutes) = 4.40
Tc Total (Overland + Gutter)= 9:31
Q = CIA
C= Weighted C Factor 0.79"(calculated above)
I= 0.78 Tc-0
.64(in/hr) `2:57
A= area(acres) '0.77,
Drainage Area#BC7
Qrequired (Cfs) = 1.57'
Provided Gutter Capacity (flowing at 0.15' below ton of curb)
Q = (1.486/n)ARv3Si/2
n= Mannings Coefficient 0.01,3
A=area(ft) 1.24
P =wetted perimeter(ft) �
R= Hydraulic Radius A/P (ft) 0.13
S = slope (ft/ft) 0.01
Qprovided (Cfs) _ 172(,
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#BC7
DRAINAGE AREA # BC 8
Contributing Area C Area(ft2) C * Area Sherwood Composite ROW
Sherwood ROW 0.7625 12150 9264 ((0.95*45)+(0.2*15))/60
Total 12150, 9264 0.7625
C = Weighted C Factor
A=Area(acres) 0.28
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 (%) 1 Return Cf
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) 13.5 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)R21 S112
n=Mannings Coefficient 0.013
R=Hydraulic Radius A/P (ft) 0:13 (0.15' below top of curb)
S = slope (ft/ft) 0.005
L=length of gutter(ft) 180
V =mean velocity(ft/s) 2.12'
Tc Gutter Flow(minutes) 141
Tc Total (Overland+Gutter) -6.33,
Q = CIA
C = Weighted C Factor 9'76 (calculated above)
I = 0.78 Tc 0.64(in/hr) 29,
A= area(acres) 028
Drainage Area#BC8
Qrequired (efs) — 0.70
Provided Gutter Capacity (flowinjZ at 0.1.5' below ton of curb)
Q = (1.486/n)AR"'Svz
n=Mannings Coefficient 0,013
A=area(ft2) 1,24
P =wetted perimeter(ft) 9;23'
R=Hydraulic Radius A/P (ft) 0:13
S = slope (ft/ft) 0.01
Qprovided (cfs) = 3:72`;
GUTTER HAS ADEQUATE CAPACITY
Drainage Area#BC8
STORM PIPE 4 TO 3
Contributing Area C Area(ft2) C * Area
Road 0.95 18126 17220!
Total 18126 17219>7
C = Weighted C Factor 0.95
A=Area(acres) 0.42
Te Total (min)= 3.31
Q = CIA
C = Weighted C Factor 0.95 (calculated above)
I = 0.78 Tc•0.64(in/hr) 4.98
A= area(acres) 0.42
Qrequired (Cfs) = 1.97'
STORM PIPE ST4toST3
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#4 to ST#3 MAX FLOW
By: Date:
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)AR "'S"'
n S= 0.004 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh"'Sv2
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 3.68 4.39 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: Westbrook Location: ST#4 to ST#3 MAX FLOW
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
________ D= 15 inches
d= 7.4 inches
Mannings Formula d n= 0.013 mannings
D 0= 178.5 degrees
Q=(1.486/n)AR "'S"'
n S= 0.004 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh1/3S11
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
0.60 1.95 0.31 3.31 2.00 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
Concl 0.013
STORM PIPE 3 TO POND
Contributing Area C Area(ft) C * Area
Road 0.95 40199 38189ti
Boulevard 0.2 5972 1 t94i
Total 46171 39383.5'
C = Weighted C Factor 0.85
A=Area(acres) 1.06
Tc Total (min) = 3.53
Q= CIA
C = Weighted C Factor 0.85 (calculated above)
I = 0.78 Tc 064(in/hr) 4.78
A = area(acres) 1.06i
Qrequired (efs) — 4.32'
STORM PIPE ST3toPOND
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#3 to POND MAX FLOW
By: Date:
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)ARh"'S"' S= 0.0044 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh"'Sv2
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 ftls flow,cfs PVC 0.013
1.20 3.30 0.36 3.86 4.61 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: Westbrook Location: ST#3 to POND
By: Date:
Chk. By: Date:
Clear Data Entry
6 Cells
INPUT
7D= 15 inches
A E-- d= 12.4 inches
Mannings Formula d n= 0.013 mannings
D 0= 98.4 degrees
Q=(1.486/n)ARh213SIl S= 0.0044 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh213SI/2
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
1.08 2.85 0.38 3.98 4.32 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
Concl 0.013
STORM PIPE I TO 2
Contributing Area C Area (ft) C * Area
ROW 0.7375 54053 39864
Boulevard/OS/Park 0.2 13214 ,2643
Lots 0.35 123710 43299
Total 190977` ` 858'0'4
C = Weighted C Factor 0.45
A =Area(acres) 438.
Tc Total (min)
Q= CIA
C = Weighted C Factor 0.45 (calculated above)
1 =0.78 Tc o.64(in/hr)
A= area(acres) 4.38
Qrequired (Cfs)
STORM PIPE ST1 toST2
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#1 TO ST#2 PEAK FLOW
By: Date:
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)ARh21IS112
S= 0.0053 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh2i3S1/2
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 4.23 5.06 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#1 TO ST#2
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 8.4 inches
Mannings Formula d 0. n= 0.013 mannings
D 0= 166.2 degrees
Q=(1.486/n)AR 213S112
h S= 0.0053 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
0.71 2.11 0.33 4.01 2.84 PE(<g"dia) 0.015
PE(>12"dia) 0.02
PE(9-12"dia) 0.017
CMP 0.025
ADS N12 0.012
HCMP 0.023
Concl 0.013
STORM PIPE 2 TO POND
Contributing Area C Area(ft2) C * Area
ROW 0.7375 96751 7,1354'
Boulevard/OS/Park 0.2 16603 3321
Lots 0.35 283695 99293'
Total 397049... 173968'
C =Weighted C Factor
A=Area(acres) 911
Tc Total (min)= 23.36
Q= CIA
C = Weighted C Factor 0.44"(calculated above)
I= 0.78 Tc o.64(in/hr) I A3''
A=area(acres) 9.11
Qrequired (Cfs)
STORM PIPE ST2topond
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#2 to POND PEAK FLOW
By: Date:
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= 57.8 degrees
Q=(1.486/n)ARn 21IS112
5= 0.0051 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rn2/ISI/2
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 4.69 &07 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#2 to POND
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 18 inches
d= 11.8 inches
Mannings Formula d n= 0.013 mannings
D 0= 143.7 degrees
Q=(1.486/n)AR 213S1r2
h S= 0.0051 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh21IS11
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
1.23 2.83 0.43 4.68 5.74 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: DETENTION POND#1 OUTLET PEAK FLOW
By: Date:
Chk. By: Date:
Clear Data Entry
0 Celis
INPUT
D= 18 inches
d= 16.88 inches
Mannings Formula d n= 0.013 mannings
D 0= 57.8 degrees
Q=(1.486/n)AR "'S"'
n S= 0.0053 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh...Sv2
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 4.78 8.23 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
STORM PIPE EX #4 TO EX#5
Contributing Area C Area(ft2) C * Area Composite ROW (Sherwood)
Sherwood ROW 0.7625 12150 9264 ((0.95*45)+(0.2*15))/60
Total 12150 9264.38 0.7625
C = Weighted C Factor
A = Area(acres) 0:28 i
Tc Total (min)= 6:33
Q = CIA
C = Weighted C Factor 0.76'(calculated above)
I= 0.78 Tc-osa(in/hr) 3.29`'
A =area(acres)
Qrequired (efs)
STORM PIPE EX4toEX5
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX#4 to EX#5 PEAK FLOW
By: Date:
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
AR Q=(1.486/n "'Svz
) h S= 0.0009 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh'/'Sv2
S=slope of channel Q=V X A
n=Manning's roughness coefficient
Solution to Mannings Equation Manning's n-values
Wetted Hydraulic
Area,ftz Perimeter,ft Radius,ft velocity ft/s flow,cfs PVC 0.013
1.20 3.30 0.36 1.74 2.08 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX#4 to EX#5
By: Date:
Chk. By: Date:
Clear Data Entry
8 Cells
INPUT
D= 15 inches
_ __
d= 6.3 inches
Mannings Formula d n= 0.013 mannings
D 0= 161.6 degrees
Q=(1.486/n)ARh113SIll S= 0.0009 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rt,v3Sv2
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
0.49 1.76 0.28 1.46 0.71 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
Concl 0.013
STORM PIPE EX#5 TO POND
Contributing Area C Area(ft2) C * Area Composite ROW(Sherwood)
Laurel Parkway ROW 0.81 21500 17415
Sherwood ROW 0.7625 12150 9264 ((0.95*45)+(0.2*15))/60
Totals : 33Ei5 0.7625
C = Weighted C Factor `�Q.79<
A =Area(acres)
Tc Total (min)
Q= CIA
C = Weighted C Factor 0.79"(calculated above)
I= 0.78 Tc o.64(in/hr) 2y
A=area(acres)
Qrequired (CfS) _ �57
STORM PIPE EX5toPOND
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX#5 to POND PEAK FLOW
By: Date:
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)AR "'Svz
n S= 0.0042 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rn2i3S11
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 3.77 4.50 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX#5 to POND
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 6.3 inches
Mannings Formula d n= 0.013 mannings
D 0= 161.6 degrees
Q=(1.486/n)ARn 213S112
S= 0.0042 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rn21IS112
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
0.49 1.76 0.28 3.15 1.54 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
Concl 0.013
STORM PIPE 3A TO 4
Contributing Area C Area(ft) C * Area Composite ROW(interior st)
ROW Interior Streets 0.7375 38869 28666 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 0 01 0.7375
Lots 0.35 107223 37528
Laurel Pkwy ROW 0.81 21200 17172
Durston ROW 0.68 14592 9923
Total 181884 93298.5
C = Weighted C Factor 0.51
A=Area(acres) 4.18
Tc Total (min) = 18.43'
Q = CIA
C = Weighted C Factor 0.51 (calculated above)
I = 0.78 Tc o.64(in/hr) 1.66';
A =area(acres) 4.18'!;
Qrcquired (efs) = 3.56':
STORM PIPE ST3AtoST4
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#3A to ST#4 PEAK FLOW
By: Date:
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
AR Q=(1.486/n "'Sv2
) n S= 0.004 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh'/'S'iz
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 3.68 4.39 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#3A to ST#4
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 10.8 inches
Mannings Formula d n= 0.013 mannings
D 0= 127.8 degrees
Q=(1.486/n)ARh21IS112
S= 0.004 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh21IS11
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
0.95 2.53 0.37 3.75 3.55 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
STORM PIPE 4 TO 3
Contributing Area C Area(ft2) C * Area Composite ROW(interior st)
ROW Interior Streets 0.7375 38869 28666 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 0 0 0.7375
Lots 0.35 107223 37528
Laurel Pkwy ROW 0.81 21200 :17',172
Durston ROW 0.68 14592 9923
Total 1818'84 932M3
C = Weighted C Factor 0.51'
A=Area(acres) 4:18'
Tc Total (min) = 18,45,'
Q = CIA
C = Weighted C Factor 0.51`,(calculated above)
I= 0.78 Tc 0.64(in/hr) 1.6b
A= area(acres) 4.18
Qrequired (Cfs)= 3.55
STORM PIPE MH4toMH3
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: MH#4 to MH#3 PEAK FLOW
By: Date:
Chk. By: Date:
Clear Data Entry
8 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 AR zi3Sii2
) n S= 0.0105 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rn2r3Sv2
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 ftls flow,cfs PVC 0.013
1.20 3.30 0.36 5.96 7.12 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: Westbrook Location: MH#4 to MH #3
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 7.8 inches
Mannings Formula d n= 0.013 mannings
D 0= 175.4 degrees
Q=(1.486/n)AR v3Sv2
n S= 0.0105 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh"'S"
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
0.64 2.01 0.32 5.48 3.54 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
Concl 0.013
STORM PIPE 3 TO 2
Contributing Area C Area(ftz) C * Area Composite ROW (interior st)
ROW Interior Streets 0.7375 38869 28666 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 0 0' 0.7375
Lots 0.35 107223 37528
Laurel Pkwy ROW 0.81 21200 _ �17172
Durston ROW 0.68 14592 9923
Total 1,81884 -93288.5
C = Weighted C Factor 0.5,1,
A =Area(acres) 4.18
Tc Total (min) = 18.97
Q = CIA
C = Weighted C Factor 0:51`(calculated above)
I = 0.78 Tc 0.64(in/hr) 1.63
A = area (acres) 4.18
Qrequired (Cfs) = 3.49`
STORM PIPE ST3toST2
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#3 to ST#2 PEAK FLOW
By: Date:
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)AR zisSv2
n S= 0.0091 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rn213S11
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 5.54 6.63 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#3 to ST#2
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 8.1 inches
Mannings Formula d n= 0.013 mannings
D 0= 170.8 degrees
Q=(1.486/n)AR zrsSvz
h S= 0.0091 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
0.68 2.06 0.33 5.18 3.50 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
STORM PIPE 2A TO 2
Contributing Area C Area(ft2) C * Area Composite ROW(interior st)
ROW Interior Streets 0.7375 16331 42044 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3300 ~660' 0.7375
Lots 0.35 96575 33801
Laurel Pkwy ROW 0.81 26918, . `21.804
Total WIN 68308.9
C = Weighted C Factor '0.48'
A=Area(acres) 129'
Tc Total (min) _ 23.68�
Q = CIA
C = Weighted C Factor 0'.48 (calculated above)
I= 0.78 Tc"0.64(in/hr) 1.41
A=area(acres) 3.29>
Qregttired (Cfs) — 2.22'
STORM PIPE ST2AtoMH2
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#2A to MH#2 PEAK FLOW
By: Date:
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=(1.486AR
/n 2r3S112
) n S= 0.006 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rn2/3S1/2
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 4.50 5.38 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: ST#2A to MH#2
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 7 inches
Mannings Formula d n= 0.013 mannings
D 0= 172.4 degrees
Q=(1.486/n)AR 213SI12
h S= 0.006 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh2i3Sv2
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
0.56 1.88 0.30 3.96 2.22 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
STORM PIPE 2 TO 1
Contributing Area C Area (ft2) C * Area Composite ROW(interior st)
ROW Interior Streets 0.7375 55200 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3300 = 650 0.7375
Lots 0.35 203798 71329'
Laurel Pkwy ROW 0.81 48118 �3897
Durston ROW 0.68 14592 9923'
Total 325008 16I597
C = Weighted C Factor 0a0
A =Area(acres) 7;4b
Tc Total (min) _ 23�.'
Q =CIA
C = Weighted C Factor 0.50 (calculated above)
I =0.78 Tc 0.64(in/hr) 1 � ;
A =area(acres) : 6
Qrequired (cfs) _ 52
TOTAL 5.24 cfs
STORM PIPE MH2toMH1
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: MH#2 to MH#1 PEAK FLOW
By: Date:
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)AR "'Svz
n S= 0.0082 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rn2i3S112
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 5.26 6.29 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: MH#2 to MH#1
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
_ _ D=C15 inches__ _
d= 11.1 inches
Mannings Formula d n= 0.013 mannings
D 0= 122.6 degrees
AR Q=(1.486/n) 213Sv2
n S= 0.0082 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)R,"S'12
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
0.97 2.59 0.38 5.39 5.25 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
STORM PIPE 1 TO EX MH 1
Contributing Area C Area (ft2) C * Area Composite ROW(interior st)
ROW Interior Streets 0.7375 55200 40710 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3300 , `' 60` 0.7375
Lots 0.35 203798I329
Laurel Pkwy ROW 0.81 48118 --38976
Durston ROW 0.68 1459223
Total 325.608 1615. 7
C =Weighted C Factor 0,
A=Area(acres) 7.4i
Tc Total (min)
Q = CIA
C = Weighted C Factor 0.50 (calculated above)
I= 0.78 Tc 064(in/hr)
A =area(acres) 7x46
Qrequired (efs) _ ",5.10
TOTAL 5.10 efs
STORM PIPE MH1toEX1
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: MH#1 to EX#1 PEAK FLOW
By: Date:
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
AR Q=(1.486/n 2r3Sv2
) n S= 0.052 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
1.20 3.30 0.36 13.25 15.85 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: MH#1 to EX#1
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 6.1 inches
Mannings Formula d n= 0.013 mannings
D 0= 158.5 degrees
0=(1.486/n)ARh213SI12 S= 0.052 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
0.47 1.73 0.27 10.92 5.12 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
STORM PIPE EX #1 TO EX#2
Contributing Area C Area(ft2) C * Area Composite ROW(interior st)
ROW Interior Streets 0.7375 55200 40710 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3300 G60 0.7375
Lots 0.35 203798 �`71329
Laurel Pkwy ROW 0.81 48118 3,8976
Durston ROW 0.68 14592 9923
Total 325008 161597i
C = Weighted C Factor 050
A=Area(acres) 7.46
Tc Total (min) _ 27;00'
Q = CIA
C = Weighted C Factor 0,50 (calculated above)
1= 0.78 Tc o.64(ln/hr) 1.30'
A =area(acres) 7.46'
Qrequired (Cfs)
EX. PIPE#5 PER ALLIED 2.95
ORIGINAL STORM DESIGN
REPORT (CFS)
TOTAL 7.77 cfs
STORM PIPE EX1toEX2
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX INLET#1 to EX MH#2 PEAK FLOW
By: Date:
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)ARh2isSv2 S= 0.028 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh213S112
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 J--9.72 11.63 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX INLET#1 to EX MH#2
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 9.4 inches
Mannings Formula d n= 0.013 mannings
D 0= 150.7 degrees
Q=(1.486/n)ARh2�35'i2 S= 0.028 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh213S1/2
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
0.81 2.28 0.35 9.58 7.75 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
STORM PIPE EX#2 TO EX#3
Contributing Area C Area(ft2) C * Area Composite ROW(interior st)
ROW Interior Streets 0.7375 55200 40710 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 3300 660 0.7375
Lots 0.35 203798 71329'
Laurel Pkwy ROW 0.81 48118 .,38976
Durston ROW 0.68 14592 9923
Total 325008 161597`
C = Weighted C Factor 0.s0
A=Area(acres) 7.46
Tc Total (min) _ 27:17
Q = CIA
C = Weighted C Factor "0.50 (calculated above)
I=0.78 Tc-O 64(in/hr) 130
A=area(acres) 7.46
Qrequired (efs)
EX. PIPE 45 PER ALLIED 2.95
ORIGINAL STORM DESIGN
REPORT (CFS)
EX. PIPE #6 PER ALLIED 7.86
ORIGINAL STORM DESIGN
REPORT(CFS)
TOTAL 15.61 cfs
STORM PIPE EX2toEX3
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX MH#2 to EX MH#3 PEAK FLOW
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
____ D= 24 inches
d= 22.51 inches
Mannings Formula d n= 0.013 mannings
D 0= 57.7 degrees
Q=(1.486 n AR ZisSvz
/ ) n S= 0.0053 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)R,"S'12
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
3.06 5.28 0.58 J-;.7;-
17.72 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX MH#2 to EX MH#3
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 24 inches
d= 18.6 inches
Mannings Formula d n= 0.013 mannings
D 0= 113.3 degrees
Q=(1.486/n)ARhzr3Sii2 S= 0.0053 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
2.61 4.31 0.61 5.96 15.58 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
STORM PIPE EX#3 TO EX #4
Contributing Area C Area(ft2) C * Area Composite ROW(interior st)
ROW Interior Streets 0.7375 55200 , 40710 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 8232 "'1646 0.7375
Lots 0.35 203798 =71329
Laurel Pkwy ROW 0.81 48118 ",:389"76
Road 0.95 18787 17848'
Durston ROW 0.68 14592 9921`
Total 348727 180431
C = Weighted C Factor 052:
A =Area(acres) 801
Tc Total (min) _ 27.42
Q = CIA
C = Weighted C Factor 0.52 (calculated above)
I = 0.78 Tc°.64(in/hr) 4
A=area(acres) 80
Qrequired (cfs)
EX. PIPE#5 PER ALLIED 2.95
ORIGINAL STORM DESIGN
REPORT (CFS)
EX. PIPE#6 PER ALLIED 7.86
ORIGINAL STORM DESIGN
REPORT(CFS)
TOTAL 16.14 cfs
STORM PIPE EX3toEX4
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX IN#3 to EX IN#4 PEAK FLOW
By: Date:
Chk. By: Date:
Clear Data Entry
8 Cells
INPUT
________ D= 24 inches
d= 22.51 inches
Mannings Formula d n= 0.013 mannings
D 0= 57.7 degrees
AR
/
Q=(1.486 n 2isSvz
) n S= 0.011 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rn2'3S12
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
3.06 5.28 0.58 8.34 25.52 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
Cone 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX IN#3 to EX IN #4
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 24 inches
d= 14.5 inches
Mannings Formula d n= 0.013 mannings
D 0= 156.0 degrees
Q=(1.486/n)AR zi3Sii2
h S= 0.011 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
1.98 3.56 0.56 8.12 16.11 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
Concl 0.013
STORM PIPE EX #4 TO EXISTING DETENTION POND 91
Contributing Area C Area(ft) C * Area Composite ROW (interior st)
ROW Interior Streets 0.7375 5520071'0 ((0.95*43)+(0.2*17))/60
OS/Park 0.2 8232 164 0.7375
Lots 0.35 203798
Laurel Pkwy ROW 0.81 481188976'
Road 0.95 27995 2659,5,E
Durston ROW 0.68 14592 9Q23
Total 357935 1',89179
C = Weighted C Factor 0;5
A= Area(acres) $;22
Tc Total (min)
Q = CIA
C = Weighted C Factor (calculated above)
I= 0.78 Tc o.ba(in/hr) '
A = area(acres) 8:22
Qrequired (Cfs) _ .5'.
EX. PIPE#5 PER ALLIED 2.95
ORIGINAL STORM DESIGN
REPORT (CFS)
EX. PIPE#6 PER ALLIED 7.86
ORIGINAL STORM DESIGN
REPORT (CFS)
TOTAL 1.6.39 Cfs
STORM PIPE EX4toEXDT#1
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX IN#4 to EX POND#1 PEAK FLOW
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 24 inches
d= 22.51 inches
Mannings Formula d n= 0.013 mannings
D 0= 57.7 degrees
AR
/
Q=(1.486 n 2/35112
) n S= 0.0051 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rh21IS11
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
3.06 5.28 0.58 5.68 17.38 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX IN#4 to EX POND#1
By: Date:
Chk. By: Date:
Clear Data Entry
A Cells
INPUT
_____
CD= 24 inches
d= 20 inches
Mannings Formula d n= 0.013 mannings
D 0= 96.4 degrees
Q=(1.486 n AR 2rsS�tz
/ ) h S= 0.0051 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
2.80 4.60 0.61 5.86 16.39 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
Concl 0.013
MANNING'S EQUATION FOR PIPE FLOW
Project: Westbrook Location: EX DETENTION POND#1 OUTLET PEAK FLOW
By: Date:
Chk. By: Date:
Clear Data Entry
0 Cells
INPUT
D= 15 inches
d= 14.07 inches
Mannings Formula d n= 0.013 mannings
Q=(1.486 n AR "'Sv2
D 0= 57.7 degrees
/ } n S= 0.0379 slope in/in
R=A/P
A=cross sectional area
P=wetted perimeter V=(1.49/n)Rnzi3S1/2
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 11.31 13.53 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
Concl 0.013
RETENTION POND # 2
REQUIRED VOLUME
1. Calculate Area and Weighted C Factor
Contributing Area C Area (ft 2) C *Area
Road 095 40199 38189
Boulevard 0.2 5972 1194'
Total 46171 39363
C=Weighted C Factor 0,85
3. Calculate Required Volume
Q = CIA
V=7200Q
C =Weighted C Factor 0.9&
1 = intensity(inihr) 0.41 (10 yr, 2hr storm)
A=Area (acres)
Q = runoff(cfs)
V= REQUIRED VOL (ft) 2669`
DETENTION POND # 3
REQUIRED VOLUME
2. Calculate Area and Weighted C Factor(Post-Development)
Contributing Area C Area (ft2) C *Area
ROW 0.7375 96751 71354
Open Land 0.2 16603 _3321
Low-Med Residential 0.35 283695 99293
Total 397049 173968
A =Area(acres) 9.1150
C= Weighted C Factor 0.44
3. Calculate TC (Pre-Development)
Tc Overland Flow
Tc = 1.87 (1.1-CC)D'/2/S'/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 Ill to 25 1.1
D = Length of Basin (ft) 983 126 to 50 1.2
51 to 100 1.25
Tc(Pre-Development) (minutes) 52
------------------------------
4. Calculate Rainfall Intensity(Duration =Pre-Development Tc)
i = 0.64x o.se(10-yr Storm, Fig. 1-3, COB Design Standards)
x= storm duration (hrs) 0.86 (Tc Pre-Development)
i=rainfall intensity(in./hr.) 0.71
5. Calculate Runoff Rate(Pre-Development)
Q = CiA
C = Rational Method Runoff Coefficient 0.2 (open land)
i = rainfall intensity (in./hr.) 0.71 (calculated above)
A=Area (acres) 9.11 (calculated above)
Q=Runoff Rate (Pre-Development)(cfs) 1.29
6. Calculate Required Pond Volume
Total Area (acres) = 9.11 acres
Weighted C = 0.44
Discharge Rate (cfs) = 1.29 cfs (Equal to Pre-Development Runoff Rate)
Duration(min) Duration(hrs) Intensity Q (cfs) Runoff Release Required
'�(in/hr) Volume Volume Storage (ft)
30 0.50 1.00 4.01 7219 2317 4903
31 0.52 0.98 3.93 7303 2394 4909
32 0.53 0.96 3.85 7384 2471 4913
33 0.55 0.94 3.77 7464 2548 4916
34 0.57 0.93 3.70 7543 2625 4917
35 0.58 0.91 3.63 7620 2703 4917
36 0.60 0.89 3.56 7695 2780 4915
37 0.62 0.88 3.50 7769 2857 4912
38 0.63 0.86 3.44 7842 2934 4908
39 0.65 0.85 3.38 7914 3012 4902
OUTLET STRUCTURE SLOT
Q=CLH 112
Q = Discharge (cfs) 1.29
C = Weir Coefficient 3.33 (per COB Design Standards)
H = Head (ft) 1.5
L = Horizontal Length (ft) 0.21
L =Slot Width (inches) 2.5
EXISTING DETENTION POND #1
REQUIRED VOLUME
2. Calculate Area and Weighted C Factor(Post-Development)
Contributing Area C Area (ft 2) C *Area
Interior St. ROW 0.7375 55200 40710'
Lots 0.35 203798 71329
Laurel Pkwy ROW 0.81 69618 56391
Durston ROW 0.68 14592 9923
Sherwood ROW 0.7625 24300 18529
Road Surface 0.95 27995 26595
Open Space 0.2 8232 1646
EX ST#1 0.5 294780 147390
EX ST#3 0.5 403599 201800
EX ST#4 0.5 58872 29436
Total 1160986 603748
A =Area(acres) 26.6526
C= Weighted C Factor 0.52
3. Calculate T, (Pre-Development)
Tc Overland Flow
Tc= 1.87 (1.1-CC)D112/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 1.1 111 to 25 1.1
D = Length of Basin (ft) 1480 126 to 50 1.2
151 to 100 1.25
-----------------------------
Tc(Pre-Development)(minutes) 63'
4. Calculate Rainfall Intensity(Duration =Pre-Development Tc)
i = 0.64x o.ss (10-yr Storm, Fig. 1-3, COB Design Standards)
x= storm duration (hrs) 1.06 (Tc Pre-Development)
i=rainfall intensity(in.1hr.) 0.62'
5. Calculate Runoff Rate(Pre-Development)
Q = CiA
C = Rational Method Runoff Coefficient 0.2;(open land)
i = rainfall intensity(in./hr.) 0.62 (calculated above)
A=Area (acres) 26.65'(calculated above)
Q=Runoff Rate (Pre-Development) (cfs) 3.29
6. Calculate Required Pond Volume
Total Area (acres) = 26.65 acres
Weighted C = 0.52
Discharge Rate (cfs) = 3.29 cfs (Equal to Pre-Development Runoff Rate)
Intensity Q. Runoff Release Required
Duration(min) Duration(hrs) (in/hr) i (cfs)n Volume Volume Storage(ft)
50 0.83 0.72 9.99 29960 9884 20076
51 0.85 0.71 9.86 30168 10081 20087
52 0.87 0.70 9.74 30374 10279 20095
53 0,88 0.69 9.62 30577 10477 20100
54 0.90 0.69 9.50 30778 10674 20103
55 0.92 0,68 9.39 30976 10872 20104
56 0.93 0.67 9.28 31172 11070 20102
57 0.95 0.66 9.17 31366 11268 20098
58 0.97 0.65 9.07 31557 11465 20092
59 0.98 0.65 8.97 31746 11663 20084
OUTLET STRUCTURE SLOT
Q=CLH 112
Q = Discharge (cfs) 3.29
C =Weir Coefficient 3.33 (per COB Design Standards)
H = Head (ft) 1.5
L= Horizontal Length (ft) 0.54
L =Slot Width(inches) 6.5