HomeMy WebLinkAboutDrainage ReportDrainage Report
for
Castlegate Subdivision -Section 7, Phase 2,
College Station; Texas
January 2007
Developer:
Greens Prairie lnvestors, Ltd.
By Greens Prairie Associates, LLC
4490 Castlegate Drive
College Station, Texas 77845
(979) 690-7250
Prepared B1 '_:
Civil Development, Ltd.
2900 Longmire Drive, Suite K
College Stati on, Texas 77 845
(979) 764-7743
CERTIFICATION
I, Joseph P. Schultz, Licensed Pro fess ional Engin eer No. 65889, State of Texas, certify that this
report for the drainage design for the Castlegate Subdivision -Section 7, Phase 2, was
prepared by me in accordance with the provisions of the City of College Station Drainage
Policy and Design Standards for the owners hereof.
TABLE OF CONTENTS
DRAINAGE REPORT
CASTLEGATE SUBDIVISION -SECTION 7, PHASE 2
CERTIFICATIO ................................................................................................................................................................. I
TABLE OF CO TE TS ....................................................................................................................................................... 2
LIST OF TABLES .................................................................................................................................................................. 2
INTRODUCTION .................................................................................................................................................................. 3
GENERAL LOCATlON AND DESCRIPTIO ................................................................................................................. 3
FLOOD HAZARD INFORMATION ................................................................................................................................... 3
DEVELOPMENT DRAINAGE PATTERNS ...................................................................................................................... 3
DRAINAGE DESIGN CRITERIA ....................................................................................................................................... 3
STORM WATER RUNOFF DETERMINATION .............................................................................................................. 4
DETENTION FACILITY DESIGN ..................................................................................................................................... 5
STORM SEWER DESIGN .................................................................................................................................................... 5
CONCLUSIONS ..................................................................................................................................................................... 6
APPENDIX A ......................................................................................................................................................................... 7
Time of Co11 ce11tratio11 Equations & Calculations
APPENDIX B ........................................................................................................................................................................ 12
Storm Sewer Inlet Design Calc11latio11s
APPENDIX C ....................................................................................................................................................................... 15
Storm Sewer Pipe & Clza1111el Design Calc11/atio11s
EXHIBIT A ........................................................................................................................................................................... 24
Post-Development Drainage Area Map
LIST OF TABLES
TABLE 1 -Rainfall Intensity Calculations .............................................................................................. 4
TABLE 2 -Time of Concentration (tc) Equations .................................................................................. 4
TABLE 3 -Po st-Development Runoff Informatio n -Storm Sewer Design ........................................... 5
DRAINAGE REPORT
CASTLEGATE SUBDIVISION -SECTION 7, PHASE 2
INTRODUCTION
The purpose of this report is to provide the hydrological effects of the construction of the
Castlegate Subdivision -Section 7, Phase 2, and to verify that the proposed stonn drainage
system meets the requirements set forth by the City of College Station Drainage Policy and
Design Standards.
GENERAL LOCATION AND DESCRIPTION
The project is located in the Cast legate Subdivision west of State Highway 6 along the north
side of Greens Prairie Road in College Station, Texas. This report addresses Section 7, Phase 2
of this subdivision, which is made up of approximately 13 acres, which is adjacent to
Castlegate Section 7, Phase 1. The site is predominantly wooded. The existing ground
elevations range from Elevation 312 to Elevation 334. The general location of the project site
is shown on the vicinity map in Exhibit A.
FLOOD HAZARD INFORMATION
The project site is located in the Spring Creek branch of the Lick Creek Drainage Basin. Most
of the proposed developed area of the site is located in a Zone X Area according to the Flood
Insurance Rate Map prepared by the Federal Emergency Management Agency (FEMA) for
Brazos County, Texas and incorporated areas dated February 9, 2000, panel number
48041 C0205-D. There is Flood Hazard Area on the east and west portions of this
development. This area is shown on Exhibit A as the 100-year floodplain limit. No residential
area of this development lies within the Flood Hazard Area.
DEVELOPMENT DRAINAGE PATTERNS
Prior to development, the storm water runoff for Section 7, Phase 2 generally flows in a
northeasterly or westerly direction until it enters tributaries of Spring Creek. Ultimately, this
runoff flows into Spring Creek and then north to the ex isting regional detention facility. Refer
to the vicinity map in Exhibit A for the location of this regional detention faci lity.
DRAINAGE DESIGN CRITERIA
The design parameters for the stonn sewer are as follows:
• The Rational Method is utilized to determine peak storm water runoff rates for the storm
sewer design.
• Design Stom1 Frequency
Sto1111 sewer system
• Runoff Coefficients
I 0 and I 00-year stonn events
Post-development (single family residenti al) c = 0.55
• Rain rai l Intensit y eq uati on s and va lu es fo r Bra1.os Co unt y can be round in Table I.
• Time of Concentration, le -Calcul at ions are based on the method found in the TR-55
publi cation. Refer to Table 2 fo r th e equati ons and Appendi x A for calculati ons. The
run off Oow paths used for calculating the post-development tim es of concentrat ion fo r th e
sto rm sewer design are shown on Ex hi bit A. For smaller drainage areas, a minimum tc of
l 0 minutes is used to detem1in e the rainfall intensit y va lu es.
STORM WATER RUNOFF DETERMINATION
The peak runoff values were detennined in accord ance with the criteria presented in the
previous section for the 5, 10, 25 , 50, and 100-year stom1 events. The drain age areas fo r the
post-development conditions for th e storm sewer des ign are shown on Exhib it A. Post-
development runoff conditions for the storm sewer des ign are summarized in Tab le 3.
TABLE 1 -Rainfall Intensity Calculations
Rainfall Intensity Values (in/hr)
Storm
Event
Is
110
l,s
lso
1100
tc =
10 min
7.693
8.635
9.861
11 .148
11.639
I = b I (tc+d)"
I = Rainfall Intensity (in/hr)
tc = L/(V*60)
le = Time of concentration (min)
L = Length (ft)
V = Velocity (ft/sec)
Brazos County:
5 year storm 10 year storm 25 year storm 50 year storm 100 year storm
b= 76 b= 80 b= 89 b= 98 b= 96
d= 8.5 d= 8.5 d= 8.5 d= 8.5 d = 8.0
e= 0.785 e= 0.763 e= 0.754 e= 0.745 e= 0.730
(Data taken from State Department of Highways and Public Transportation Hydraulic Manual, page 2-16)
TABLE 2 -Time of Concentration (tc) Equations
Th e time of concentration was determined usin g methods found in TR-55, "Urban
Hydrology for Small Wat ersheds. " The equations are as follows.·
Time of Concentration:
For Shee t Flow: T,
For Shallow Conc entrated Flow:
Reier to A ppendix/\ for calc ulations.
Tc= T1(shcel llow) + T1(rnnccnl raled shecl 1101\)
where: T, =Travel Time, minutes
where: T, =travel time, hours
n =Manning 's roughness coefficient
L = flow length, feet
P2 = 2-year, 24-hou r rainfall = 45''
s = land slope, ft/ft
T, = L I (60*V)
where: T, =travel time, minutes
V =Velocity. l"ps (See Fig 3-1. /\pp. /\)
I, = flow length. kct
TABLE 3 -: Post-Development Runoff In formation -Storm Sewer Design
5 year storm 10 year storm 25 year storm 50 year storm 100 year storm le Area# A c
125 0 25 lso Oso 1100 0 100 15 Os 110 0 10
(acres) (min) (in/hr) (cfs) (in/hr) (cfs) (in/hr) (cfs) (in/hr) (cfs) (in/hr) (cfs)
5 1.63 0.55 11 .7 7.180 6.44 8.074 7.24 9.229 8.27 10.441 9.36 10.897 9.77
6 1.58 0.55 22.8 5.091 4.42 5.781 5.02 6.634 5.76 7.534 6.55 7.864 6.83
13 1.30 0.55 10 7.693 5.50 8.635 6.17 9.861 7.05 11.148 7.97 11 .639 8.32
14 0.10 0.55 10 7.693 0.42 8.635 0.47 9.861 0.54 11.148 0.61 11 .639 0.64
15 0.13 0.55 10 7.693 0.55 8.635 0.62 9.861 0.71 11.148 0.80 11 .639 0.83
16 2.49 0.55 24.0 4.943 6.77 5.617 7.69 6.448 8.83 7.326 10.03 7.647 10.47
DETENTION FACILITY DESIGN
The detention facility handling the runoff from thi s site is a regional facility designed by LJ A
Engi neering & Surveying, lnc. The detention fac ility is located adjacent to Spring Creek pri or
to Spring Creek enterin g the State Hi ghway 6 right-of-way. Also, a detention pond was
constructed upstream of Cast legate Drive, noted as "Ex isting Pond" on Exhibit A, to reduce the
peak flow res ulting from the Castlegate development.
STORM SEWER DESIGN
The stom1 sewer piping material fo r this project has been selected to be High Density Poly-
Ethylene (HDPE) pipe meeting the requirements of AASHTO M294, Type S with watertight
joints. The curb inlets will be cast-in-place concrete.
Appendix B presents a summary of th e storm sewer inl et design parameters and calcul ations.
The inlets were designed based on a l 0-year design storm. As per College Station guidelines,
the capacities of inlets in sump were reduced by l 0% to allow for clogging.
lnl ets for the residential streets were located to maintain a gutter flow depth of 5" or less. This
design depth wi ll prevent th e spread of water from reaching the crown of the road fo r the 10-
year storm event. Refer to Appendix B for a summary of the gutter flo w depths. The runo ff
intercepted by the proposed stom1 sewer inlets was calculated using the fo llowing equations.
The depth of flow in the gutter was detennined by using th e Straight Crown Flow equation.
The capacities for the inlets in sump (lnlets 5 & 6) were calculated using the lnl ets in Sumps,
Weir Flow equation with a maximum allowable depth of 7" (5" gutter fl ow plus 2" gutter
depression). These equations and resulting data are summarized in Appendix B. There are no
Inl ets On Grade for this phase of development. The maximum depth in the proposed streets is
4.10 inch es for th e IO-year storm event and 4.94 inches for th e 100-year storm event. These
eq uations and the resulting data are summarized in Appendi x B. The area between the ri ght-
of-way and the curb line of the streets will be graded as shown on th e Grad in g Pl an (re fer to
construction plans) to provide a minimum of 6" of freeboard above the curb lin e. Thi s will
ensure that the runoff fro m the I 00-year storm event wi ll remain within the street ri ght-of-way.
Appendi x C presents a summ ary of th e storm se\\'er pipe design parameters and calculations.
Al l pipes are 18" in di ameter or larger. For pipes with 18" and 24" diallleters, th e cro ss-
sectional area is redu ced by 2Y%, as per Co llege Stati o n requi rements. A surnlll ary o f how thi s
wa s ac hi eved is sho\\·11 i11 Appendix Caswell The pipes for the storm sewer svs tc111 "·ere
designed based on the l 0-year storm event. Based on the depth of fl ow in the street determined
fo r the 100-year storm event, this runo ff will be contained within the street right-of-way until it
enters the storm sewer system. As required by Coll ege Station, the velocity o f fl ovv in th e
stonn sewer pipe system is not lower than 2.5 feet per second , and it does not exceed 15 fee t
per second . As th e data shows, even during low fl ow conditi ons, th e velocity in the p ipes will
exceed 2.5 feet per second and prevent sediment build-up in the pipes. The maximum fl ow in
the storm sewer pipe system will occur in Pipe No. 12. The maximum velocity for the pipe
system in this development will be 10.1 feet per second and will occur in Pipe No. 12.
Appendix C contains a summary of the pipe calcul ati ons, showin g both Mannings Equation and
cul vert calcul ator data.
CHANNEL NO. 1 DESIGN
Storm water collected by the stom1 sewer system for this phase of the development w i II be
discharged into a proposed grass-lined channel. T hi s channe l will carry the storm water to the
100-year fl oodplain located adj acent to this development, th en into an existing drainage
channel, and then in to the existing pond. The channel will be a trapezoidal channel with 4H: IV
sides, 0.4% slope, 6' bottom width, and 18" in depth. Data pertaining to thi s channel design
can be found in Appendix C.
CONCLUSIONS
The construction of this project will increase the s tom1 water runo ff from this site. The
proposed storm sewer system should adequately control the runoff and release it into an
existing drainage, whi ch discharges into tributaries of Spring Creek. As shown in the
Castlegate Floodplain Analys is, the Castl e gate Subdivision does not have a signi fican t effect on
the 100-year floodplain water surface elevations or the floodplain limits. The existing pond
also prov ides detention for Castlegate, and there w ill be no impact on the downstream
properties w ithin Castlegate. The regional detention facility sho uld adequately control the peak
post-development runoff so that it w ill not have any impact on the properties downstream of
the Crowley Tract resulting from thi s development.
APPENDIX A
Time of Concentration Equations & Calculations
Castlegate Subdivision -Section 7, Phase 2
Post-Development Time of Concentration Calculations
Refer to Exhibit A for flow path locations.
Drainage Area #5
Sheet Flow:
L= 100
T1= 0.007(L*nt~
(P)os*(S)o4
Concentrated Flow:
L= 240
T1= L/(60*V)
Gutter Flow 1:
L= 63
T1= L/(60*V)
Gutter Flow 2:
L= 80
T1= L/(60*V)
n=
P=
=
V=
=
V=
=
V=
=
0.24 (dense grass)
4.5
Elev,=
0.149 hours= .._I ___ 8_._9_m_in __ ~
2.05 fps (unpaved)
Elev,=
2.0 min
3.45 fps (paved)
Elev,=
0.3 min
2.50 fps (paved)
Elev,=
0.5 min
Slope=
Slope=
Slope=
Slope=
0.042
0.0150
0.0286
0.0150
Drainage Area #6
Sheet Flow: n= 0.24 (dense grass)
P= 4.5
L= 175 Elev1= Elev2= Slope= 0.022
T,= 0.007(L *nt~ = 0.302 hours= I 18.1 min
(P)os*(S)o4
Concentrated Flow: V= 2.8 fps (unpaved)
L= 140 Elev1= Elev2= Slope= 0.0300
T,= L/(60*V) = 0.8 min
Gutter Flow 1: V= 1.75 fps (paved)
L= 182 Elev1= Elev2= Slope= 0.0074
T,= L/(60*V) = 1.7 min
Gutter Flow 2: V= 2.05 fps (paved)
L= 126 Elev1= Elev2= Slope= 0.0100
T,= L/(60*V) = 1.0 min
Gutter Flow 3: V= 4.00 fps (paved)
L= 158 Elev1= Elev2= Slope= 0.0390
Ti= L/(60*V) = 0.7 min
Gutter Flow 4: V= 2.5 fps (paved)
L= 80 Elev1= Elev2= Slope= 0.0150
T,= L/(60*V) = 0.5 min
ITc= 22.8 min
Drainage Area #16
Sheet Flow: n= 0.24 (dense grass)
P= 4.5
L= 150 Elev,= Elev2= Slope= 0.015
T1= 0.007(L *nt" = 0.311 hours= I 18.7 min
(P)°s*(S)o4
Gutter Flow 1 : V= 1.85 fps (paved)
L= 311 Elev,= Elev2= Slope= 0.0080
T1= L/(60*V) = 2.8 min
Gutter Flow 2: V= 3.2 fps (paved)
L= 408 Elev,= Elev2= Slope= 0.0280
T1= L/(60*V) = 2.1 min
Gutter Flow 3: V= 2.4 fps (paved)
L= 60 Elev1= Elev2= Slope= 0.0140
T1= L/(60*V) = 0.4 min
ITc= 24.0 min
•
~
4--~
4-
<1J a.
0 .-
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VI
I-
::J
0 u I-
<1J .._, .., :x
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.10
.06
.04
.02 -
.01 -
.005
' 1
j
' I
' I
I
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b
::..q_, ,--:;,
'tr ::.. ~f!; j'
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2
'
;
I ,
'
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4
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Average velocity, ft/sec
, .
' , ,
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Fiicu~ l -1.-Avcrar:c vcl<><:iti"s for c•limatinic trJvcl time for •hallow c-onccntratcd now.
(2 10-Vl-TR-55. Second Ed .. June L98G)
I
20
\
APPENDIX B
Storm Sewer Inlet Design Calculations
I -'
Castlegate Subdivision
Sect ion 7, Phase 2
Depth of Flow in Street Gutter
Gutter A
Location c
(acres)
C1 1.63 0.55 --
C2 1.58 0.55
C3 0.37 0.55
C4 1.25 0.55
-
F1 0.10 0.55 -F2 1.30 0.55 --F3 0.13 0.55 ----- -
F4 2.49 0.55 ------
F5 0.44 0.55 ----- -
F6 1.02 0.55
Transverse (Crown) slope (ft/ft)
27' street = 0.0330
Slope
(ft/ft)
0.0150
0.0150
0.0100
0.0100
0.0200
0.0194 -
0.0266 -
0.0140
0.0080 --
0.0080
10-year storm
0 10 Y10-actual
(cfs) (ft) (in)
7.24 0.354 4.25 -
5.02 0.309 3.70 -
1.76 0.225 2.70
4 09 0.308 3.70
0.47 0.121 1.45
6.17 0.318 3.81
0.62 0.126 1.52 -·---7.69 0.367 4.40
2.09 0.250 3.00
3.35 0.298 3.58
Straight Crown Flow (Solved to find actual depth of flow in gutter, y):
Q = 0.56 * (z/n) * S112 * y8'3 ¢ y ={Q I [0.56 * (z/n) * S112]}318
n =Roughness Coefficient= 0.018
S = Streel/Gutter Slope (ft/ft)
y = Depth of flow at inlet (ft)
z = Reciprocal of crown slope:
27' street = 30
100-year storm
0 100 Y100
(cfs) (ft) (in)
9.77 0.396 4.75
6.83 0.346 4.16 ---2.37 0.251 3.01
5.57 0.346 4.15
0.64 0.135 1.62 --
8.32 0.355 4.26
0.83 0.141 1.70 ----10.47 0.412 4.94 -----
2.82 0.280 3.35 ---
4.55 0.335 4.02
Castlegate Subdivision
Section 7, Phase 2
Inlet Length Calculations
Inlets In Sump
Inlet# Length & Type Flow from
Area #
5 1 o· Recessed 13
14
'i 10· Recessed 15
16
A c
(acres)
1.30 0.55
0.10 0.55
0.13 0.55 -2.49 0.55
Transverse (Crown) slope (fVft) = 0.033
o,. O carry O\ler
(cfs) (cfs) from lnlet1'
6.17 -0.47
0.62
7.69
Straight Crown Flow (Solved to find actual depth of flow, y):
Q = 0.56 * (z/n} * S112 * y813 <:> y ={Q I [0.56 * (z/n) * S112]}318
n = Roughness Coefficient = 0.018
z = Reciprocal of crown slope = 30
S = StreeVGutter Slope (fVft)
y = Depth of flow at inlet (ft)
10 year storm
Orotal O rotal+10Y. Y10-actual
(cfs) (cfs) (ft) (in)
6.17 6.79 0.298 3.58 --0.47 0.52 0.114 1.37
0.62 0.68 0.126 1.51 ---------------7.69 8.46 0.324 3.88
-
100 year storm
L10-Req'd L10.ac1ual o, .. Ocarry over Orotal Orotal•10.,..
(ft) (ft) (cfs) (cfs)
8.32 5.48 10 ----
0.64
0.83 6.85 10 -----
10.47
"using v ..... = r = 0.583'
Inlets in sumps, Weir Flow:
L = QI (3 * y312} ¢ y = (Q I 3L)213
L = Length of inlet opening (ft)
Q =Flow at inlet (cfs)
y = total depth of flow on inlet (ft)
max y for inlet in sump = 7" = 0.583'
from Inlet # (cfs) (cfs)
8.32 9.15
0.64 0.70
0.83 0.92 --10.47 11.52
Y100
(ft) (i n)
0.476 5.71
0.556 6.67
APPENDIXC
Storm Sewer Pipe & Channel Design Calculations
1 .~
Castlegate Subdivision -Section 7, Phase 2
Pipe Calculations -Mannings Equation
10-year Storm
Pipe Size Length Slope Outlet Invert Contributing Contributing Tc 110 0 10 Mannings 1100 Inlet Invert Elev Elev Area Area "Actual Design V10 Travel Time, t110 No. Numbers •;.Full (in) (ft) (%) (ft) (ft) (acres) (min) (in/hr) (cfs) (cfs) (fps) (sec) I (min) (in/hr)
12 24 143.3 1.75 310.27 307.75 13,14,15,16 4.02 24.0 5.62 12.42 20.06 9.6 62.9 __ 1_5 __ 1~ .~ .,___ -13 24 73.9 2.24 312.02 310.37 13,14 1.40 10.0 8.63 6.65 10.74 9.0 63.8 8 0.14 11.64
·rhese values reflect the actual flow for the 18" & 24" pipes. The design flow for these pipe sizes reflects a 25% reduction 1n pipe area.
(Refer to attached calculation for specific information.)
Channel Summary
Bottom Width Side Slopes Slope 10-year storm 100-year storm Channel
Channel No. Design/Actual Flow Depth v,. Design/Actual Flow Depth V100 Lining
(in) (H:V) (%) (els) (In) (fps) (cfs) (in) (fps) Material
1 72 4:1 0.40 12.42 9.1 1.8 16.91 10.7 2.0 Grass
100-year Storm
0 100 Mannings
"Actual Design V,oo Travel Time, 11100 % Full (sec) I (cfs) (cfs) (fps) (min)
16.91 27.31 10.1 80.4 14 I 0.24 -----8.96 14.47 9.4 81.2 8 0.13
Castlegate Subdivision -Section 7, Ph ase 2
Pipe Calculations -Culvert Calculator
Size Length Slope Inlet Invert Outlet #of Elev Invert Elev Culvert No. Barrels
(in) (ft) (%) (ft) (ft)
12 1 24 143.3 1.75 310.27 307.75
13 1 24 73.9 2.24 312.02 310.37
Top of Road 25-year storm 100-year storrn
Design Flow v,. HW Design Flow V,.o HW
(ft) (cfs) (fps) (ft) (cfs) (fps) (ft)
315.90 23.02 7.3 314.46 27.31 8.7 315.67
317.02 12.26 3.9 315.07 14.47 4.6 316.51
City of College Station requirement to Reduce Cross-Sectional Area of 18" & 24" Pipes by 25%
Using Mannings Equation from page 48 of the College Station Drainage Policy & Design Standards Manual:
Q = 1.49/n *A* R213 * S112
Q =Flow Capacity (cfs)
18" Pipe:
Pipe size (inches)= 18
Wetted Perimeter W P· (ft)= 4.71
Cross-Sectional Area A, (ft2) = 1.766
Reduced Area AR, (ft2) = 1.325
Hydraulic Radius R =A/WP, (ft)= 0.375
Reduced Hydr Radius RR = AR/Wp, (ft)= 0.281
Roughness Coefficient n = 0.014
Friction Slope of Conduit Sr. (ft/ft)= 0.01
Example Calculation:
Slope Flow Capacity Reduced Flow Capacity % Difference
s Q
0.005 6.91 --0.006 7.57 --· --0.007 8.18
24" Pipe:
Pipe size (inches) =
Wetted Perimeter WP• (ft) =
Cross-Sectional Area A, (ft2) =
Reduced Area AR, (ft2) =
Oreduced
4.28 -·-4.69 --5.06
Hydraulic Radius R = A/WP• (ft) =
Reduced Hydr Radius RR = AR/WP' (ft) =
Roughness Coefficient n =
Friction Slope of Conduit Sr. (ft/ft) =
Example Calculation:
Slope Flow Capacity Reduced Flow Capacity
s Q Qreduced
0.005 14.89 9.22
0.006 16.31 10.1 -0.007 17.61 10.9
Conclusion:
Oreduced/Q
0.619 -0.619 ·-0.619
24
6.28
3.14
2.355
0.5
0.375
0.014
0.01
-
·-
% Difference
QreduceiQ
0.619
0.619
0.619
Multiply actual Q in 18" & 24" pipes by 1.615 to reflect a 25% reduction in the
cross-sectional area called for on page 4 7, paragraph 5 of the College Station
Drainage Policy & Design Standards manual.
Pipe 12 -10 Year Storm
Manning Pipe Calculator
Given Input Data:
Shape .......................... .
Solving for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Mann ing's n .................... .
Computed Results:
Depth .......................... ·
Area ........................... .
We t t ed Area .................... .
Wetted Perimeter ............... .
Perimeter ...................... .
Velocity ....................... .
Hyd raulic Radius ............... .
Percent Full ................... .
Ful l flow Flowrate ............. .
Full flow velocity ............. .
Circular
Depth of Flow
24.0000 in
20.0600 cfs
0.0175 ft/ft
0.0140
15.1053 in
3.1416 ft2
2.0825 ft2
43.9812 in
75.3982 in
9.6326 fps
6.8184 in
62.9387 %
27.7890 cfs
8.8455 fps
Pipe 12 -100 Year Storm
Manning Pipe Calculator
Given I nput Data:
Shape .......................... .
Solving for .................... .
Diameter ....................... .
Flowrate ....................... .
Slope .......................... .
Manning's n .................... .
Computed Results:
Dept h .......................... .
Area ........................... .
Wetted Area .................... .
Wetted Perime t er ............... .
Perimeter ...................... .
Velocity ....................... .
Hydraulic Radius ............... .
Percent Full ................... .
Fu ll flow Fl owrate ............. .
Fu ll flow ve l ocity ............. .
Circular
Depth of Flow
24.0000 in
27.3100 cfs
0.0175 ft/ft
0.0140
19.3070 in
3.1416 ft2
2 .7085 f t2
53.4118 in
75.3982 i n
10.0831 fps
7.3022 in
80.4458 %
27.7890 cfs
8 .8455 fps
Casllegate Subdi v i s io n
College c~l..it.io11 , Tc;-:c!c:
Sec l ion ·:1 Pllc'l se 2
Pipe 13 -10 Ye a r Storm
Manni ng Pipe Calculator
Given Input Data:
Shape . . . . . . . ..... .
Solving for
Diameter
Flowrate .. .
Slope ............ .
Manning's n ...... .
Computed Results:
Depth ..... .
Area ................... .
Wetted Area ............. .
Wetted Perimeter
Perimeter ...... .
Velocity ....... .
Hydraulic Radius
Percent Full ....
Full flow Flowrate
Full flow vel ocity
Circular
Depth of Flow
24.0000 in
10 .7400 cfs
0.0224 ft/ft
0.0140
9. 6718 in
3 .1416 ft2
1.1852 ft2
33. 0130 in
75.3982 in
9.0617 fps
5.1698 in
40.2991 %
31.4397 cfs
10 .0076 fps
Pipe 13 -100 Year Storm
Manning Pipe Calculator
Giv en Input Data:
Shape . . . . . . . . . . . . . . . .... .
Solving for . . . . . . . . . . . . . . .... .
Diameter ....................... .
Flowrate .................... .
Slope ....................... .
Manning's n ....
Computed Results:
Depth ........ .
Area ........................... .
Wetted Area ............... .
Wetted Perimeter .......... .
Perimeter ................ .
Velocity ................ .
Hydraulic Radius ..
Percent Full ..... .
Full flow Flowrate
Full flow velocity ............ .
Circular
Depth of Flow
24 .0000 in
14.4700 cfs
0.0224 ft/ft
0.0140
11.4340 in
3.1416 ft2
1.4765 ft2
36.5668 in
75.3982 in
9.8002 fps
5.8145 in
47 .6418 %
31.4397 cfs
10 .0076 fps
Cn~; l eqate Subdi·1 i s i o 11
r·. I J ,·CJc· ·L .1L. i < 11, ·re:·:<1~:
Sect i c111 Phase '
Pipe 12 -10 Year Storm
Culvert Calculator
Entered Data:
Shape ........... .
Number of Barrels
Solving for ........ .
Chart Number ....... .
Scale Number ............... .
Chart Description .......... .
Scale Description .......... .
Overtopping .................. .
Flowrate ..................... .
Manning's n ..... .
Roadway Elevation
Inlet Elevation ..
Outlet Elevation
Diameter ......... .
Length ........... .
Entrance Loss ............ .
Tailwater ...
Computed Results:
Headwater ...................... .
Slope .......................... .
Ve locity ....................... .
Circular
1
Headwater
1
1
CONCRETE PIPE CULVERT; NO BEVELED RING ENTRANCE
SQUARE EDGE ENTRANCE WITH HEADWALL
Off
23.0200 cfs
0.0140
315.9000 ft
310.2700 ft
307.7500 ft
24.0000 in
143.3000 ft
0.5000
3.7500 ft
314.4642 ft Outlet Control
0.0176 ft/ft
7.3275 fps
Pipe 12 -100 Year Storm
Culvert Calculator
Entered Data:
Shape ...................... .
Number of Barrels .......... .
Solving for ................ .
Chart Number ............... .
Scale Number ................ .
Chart Description .............. .
Scale Description .............. .
Overtopping . . ................. .
Flowrate ................. .
Manning's n ........ .
Roadway Elevation .. .
Inlet Elevation .... .
Outlet Elevation ... .
Diameter ................ .
Length .................. .
Entrance Loss ........... .
Tailwater ..
Computed Results:
Headwater
Slope ...
Velocity .
Circular
1
Headwater
1
1
CONCRETE PIPE CULVERT; NO BEVELED RING ENTRANCE
SQUARE EDGE ENTRANCE WITH HEADWALL
Off
27.3100 cfs
0.0140
315.9000 ft
310.2700 ft
307 .7500 ft
24 .0000 in
143.3000 ft
0.5000
3.7500 ft
315.6719 ft Outlet Control
0.0176 ft /ft
8.6930 fps
Cas tl esia ro. SubcJ i··i sinn
Coilf_'.~1 r ~;t1 ·i 1)t1, T f ·.··1::
.~:;c·c 1 c.'11 7 Pl1r::i SE:· -,
Pipe 13 -10 Year Storm
Culvert Calculator
Entered Data:
Shape ........... .
Number of Barrels
Solving for .
Chart Number .......... .
Scale Number ................ .
Chart Description ........... .
Scale Description ........... .
Overtopping
Flowrate ............ .
Manning's n . . . . . . . . . .... .
Roadway Elevat ion ............ .
Inl et Elevation ............. .
Outlet Elevation .......... .
Diameter .... .
Length ...... .
Entrance Loss
Tailwater ...
Comput ed Results:
Headwater ................... .
Slope ........................ .
Velocity ..................... .
Circular
1
Headwater
1
1
CONCRETE PIPE CULVERT; NO BEVELED RIIJG ENTRANCE
SQUARE EDGE ENTRANCE WITH HEADWALL
Off
12.2600 c f s
0.0140
317 .0200 ft
312.0200 ft
310.3700 ft
24.0000 i n
73 .9000 ft
0.5000
4.0900 ft
315.0655 ft Outlet Control
0.0223 ft/ft
3.9025 fps
Pipe 13 -100 Year Storm
Culvert Calculator
En tered Data:
Shape ................... .
Number of Barrels ....... .
Solving for .................... .
Chart Number ................... .
Scale Number ............... .
Chart Description ......... .
Scale Description ........ .
Overtopping ............. .
Flowrate ................. .
Manning's n .............. .
Roadway Elevation ............. .
I n let Elevation .......... .
Outlet Elevation ......... .
Diameter .... .
Length ...... .
Entrance Loss
Tailwater ....
Computed Results:
Headwater .
Slope ...
Velocity ...
Cast leg<itr· :·uhdi-.1 i sic'f1
.. J J<"CJ '-' .·· ol I• 11, 'ic:-.i~·
Circular
1
Headwater
1
1
CONCRETE PIPE CULVERT; NO BEVELED RING ENTRANCE
SQUARE EDGE ENTRANCE WITH HEADWALL
Off
14.4700 cfs
0.0140
317 .020 0 ft
312.0200 ft
310.3700 ft
24.0000 in
73.9000 ft
0.5000
5.3000 ft
316 .5135 ft Outlet Control
0.0223 ft/ft
4.6059 fps
Channel 1 -10 Year Storm
Channel Calculator
Given I nput Data:
Shape .......................... .
Sol ving for .................... .
Flowrate ....................... .
Slope .......................... .
Manning's n .................... .
Height ......................... .
Bottom width ................... .
Left slope ..................... .
Right slope .................... .
Computed Results:
De pth .......................... .
Velocity ....................... .
Full Flowrate .................. .
Flow area ...................... .
Flow perimeter ................. .
Hydraulic radius ............... .
Top width ...................... .
Area ........................... .
Perimeter ...................... .
Percent full ................... .
Trapezoidal
Depth of Flow
12 .4200 cfs
0.0040 ft/ft
0.0350
18.0000 in
72.0000 in
0.2500 ft/ft (V/H)
0.2500 ft/ft (V/H)
9.0756 in
1.8196 fps
47.6840 cfs
6.8257 ft2
146.8390 in
6.6938 in
144.6045 in
18 .0000 ft2
220 .4318 in
50 .4198 %
Channel 1 -100 Year Storm
Channel Calculator
Giv en Input Data:
Shape .......................... .
Solving for .................... .
Flowrate ....................... .
Slope .......................... .
Manning's n .................... .
Height ......................... .
Bottom width ................... .
Left slope ..................... .
Right slope .................... .
Computed Results :
Depth .......................... .
Velocity ....................... .
Full Flowrate .................. .
Flow area ...................... .
Flow perimeter ................. .
Hydraulic radius ............... .
Top width ...................... .
Area .......... .
Perimeter ...................... .
Percent full ................... .
C.1,;t l e~1 ate Suhcl i··1,·1c_,11
:: ·, l . ( 4.JC ~-:; L I' l (_•t t I ·1 . I;.
'.'";('-!"'" t i Oil
Trapezoidal
Depth of Flow
16 .9000 cfs
0.0040 ft /f t
0.0350
18 .0000 in
72.0000 in
0.2500 ft/ft (V/H)
0. 2500 ft /ft (V/H)
10.6703 in
1.9887 fps
47.6840 cfs
8.4978 ft2
15 9.9898 in
7 .6485 in
157 .3626 in
18.0000 ft2
220.4318 in
59.2796 %
EXHIBIT A
Post-Development Drainage Area Map