HomeMy WebLinkAboutDrainage Report - VPAC IIADRAINAGE REPORT FOR
CITY OF COLLEGE STATION
PARKS & RECREATION DEPARTMENT
VETERANS PARK AND ATHLETIC COMPLEX
PHASE IIA
OE JOB NO. 675.002-PA/PB
COLLEGE STATION JOB NO. PK0501
July 2007
Prepared by:
O’MALLEY ENGINEERS, L.L.P.
P.O. Box 1976
Brenham, Texas 77834-1976
Veterans Park and Athletic Complex – Phase IIA Drainage Report
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TABLE OF CONTENTS
CERTIFICATION SHEET
EXECUTIVE SUMMARY
GENERAL LOCATION AND DESCRIPTION OF PROJECT AREA ........................................1
DRAINAGE WATERSHED AND STUDY AREA.......................................................................1
DRAINAGE DESIGN CRITERIA................................................................................................. 2
DRAINAGE SYSTEM DESIGN................................................................................................... 2
CONCLUSIONS.............................................................................................................................3
REFERENCES ...............................................................................................................................4
APPENDICES
APPENDIX A: FEMA MAP NOS. 48041C0161C & 48041C0142C WITH PROJECT SITE
ILLUSTRATED
APPENDIX B: DRAINAGE AREA MAPS
APPENDIX C: WINSTORM REPORT – 10-YEAR FREQUENCY STORM
APPENDIX D: NRCS DRAINAGE CALCULATIONS
APPENDIX E: DRAINAGE SYSTEM DESIGN
APPENDIX F: THYSYS CULVERT REPORT – 10-YEAR FREQUENCY STORM
APPENDIX G: AUTODESK LAND DESKTOP CHANNEL CALCULATOR REPORT –
10-YEAR FREQUENCY STORM
APPENDIX H: 100-YEAR FREQUENCY STORM REPORTS
APPENDIX I: OVERALL SITE LAYOUT
APPENDIX J: PENDING TXDOT PERMIT
Veterans Park and Athletic Complex – Phase IIA Drainage Report
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CERTIFICATION
This report for the drainage design of the City of College Station Veterans Park and Athletic
Complex was prepared under my supervision in accordance with provisions of the Bryan/College
Station Unified Drainage Design Guidelines for the owners of the property. All licenses and
permits required by any and all state and federal regulatory agencies for the proposed drainage
improvements have been issued.
Robert C. Schmidt, P.E.
State of Texas No. 50465
Veterans Park and Athletic Complex – Phase IIA Drainage Report
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EXECUTIVE SUMMARY
The following drainage report was prepared by Robert C. Schmidt, P.E. of O’Malley Engineers,
L.L.P. (OE) for the City of College Station Parks and Recreation Department (PARD) and
submitted on July 9, 2007. The contact information for Mr. Schmidt and the PARD are as
follows:
Robert C. Schmidt, P.E.
O’Malley Engineers, L.L.P.
203 South Jackson Street
Brenham, Texas 77833
Phone: 979-836-7937
Fax: 979-836-7936
rcs@omalleyengineers.com
Mr. Eric Ploeger
Parks & Recreation Department
City of College Station
1101 Texas Avenue
College Station, Texas 77840-2499
Phase IIA of the Veterans Park and Athletic Complex (VPAC) involves approximately one third
(1/3) of the 150.00 acre tract. Phases I and II each contained approximately one third (1/3) of the
overall tract. Phase I has been completed and Phase II is currently under construction. The final
phase of this development is Phase III, which has not been designed. Phase IIA involves
extending Veterans Parkway to tie-into State Highway 60, storm sewer along the parkway, a
culvert crossing, drainage channel to the Carters Creek floodplain and site grading.
The VPAC site is located in the Carters Creek watershed between State Highway 30 and State
Highway 60 in the City of College Station, Brazos County, Texas. The site is bounded to the
south by the Carters Creek floodplain and to the north by Hudson Creek. Because the property is
located within and adjacent to the Carters Creek floodplain, detention is not required by the City
of College Station for this site.
The site has very little topsoil, leading to a lack of vegetation. Stormwater run-off enters the
project site at the northwest corner of the property and flows overland in the form of sheet flow
to the south where it enters the Carters Creek floodplain and leaves the property.
The stormwater will continue to flow overland and either flow directly through proposed dual six
feet (6 ft.) by three feet (3 ft.) box culverts that cross Veterans Parkway or will enter one of
several inlets along the street. All water entering the inlets will flow through the underground
storm drainage system and outfall to a proposed drainage channel at the end of the culvert. The
proposed channel will carry the stormwater south approximately 833 feet where it will then fan
out into the floodplain.
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OE has worked with the City and the Texas Department of Transportation (TxDOT) to complete
Phase IIA of this project. TxDOT was involved in the design of the Veterans Parkway
intersection with State Highway 60. The PARD has applied for a permit from TxDOT for the
tie-in.
The drainage report for this project includes one four page drainage report with appendices dated
July 3, 2007, one 19 sheet set of construction drawings dated July 3, 2007 and one specification
and contract document book dated July 3, 2007.
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GENERAL LOCATION AND DESCRIPTION OF PROJECT AREA
The Veterans Park and Athletic Complex (VPAC) is located between State Highway 30 and
State Highway 60 on the northeast side of College Station. The park is located inside the City of
College Station, Brazos County, Texas and is owned by the City of College Station. The 150.00
acre tract is bounded on the south by the Carters Creek floodplain and on the northeast by
Hudson Creek. The land directly to the north is primarily undeveloped except for the existing
Texas A&M University facility to the northwest. The properties directly across State
Highway 30 and State Highway 60 and bordering the VPAC property are all currently
undeveloped. Phase I of the VPAC was completed in September 2002 and Phase II is currently
under construction. The VPAC is proposed to contain three phases, each encompassing
approximately one-third (1/3) of the overall project area. The current phase, Phase IIA, is to
extend Veterans Parkway to tie-into State Highway 60. The project also involves a storm sewer
system along Veterans Parkway, a culvert crossing the street and a drainage channel from the
culvert to the Carters Creek floodplain. The entire project site drains into the Carters Creek
watershed. An overall site layout is included in Appendix I. The undeveloped portion of this
tract has very little topsoil or vegetation.
DRAINAGE WATERSHED AND STUDY AREA
Phase IIA of the VPAC drains directly into the Carters Creek floodplain. The floodplain for
Carters Creek is shown on the City of College Station FEMA Floodplain Panel Nos.
48041C161C and 48041C0142C (Appendix A). The existing land uses for the drainage areas
affecting this project are pasture/ranch lands, undeveloped commercial and commercial uses.
Drawings showing the drainage areas used in this study may be referenced in Appendix B. The
run-off from the area directly north of the park, Drainage Area K-2, flows over land to a natural
channel that flows south and enters the VPAC at the northwest corner. The channel then fans out
and the run-off flows over land across the park property and to the Carters Creek floodplain. The
run-off from the area on the northwest side of State Highway 60, Drainage Area K-1, crosses the
highway through a culvert and flows over land to the channel located in Drainage Area K-2. The
proposed drainage plan will allow the water to flow over land from drainage areas K-1 and K-2
to a culvert that crosses under Veterans Parkway. The culvert will empty into a trapezoidal
drainage channel which runs to the south toward the Carters Creek floodplain. The flow from
drainage areas J-10 through J-70 will enter into the storm sewer system along Veterans Parkway
and discharge at the end of the culvert into the proposed drainage channel. From the channel, the
water will flow over land through the floodplain into Carters Creek. The proposed drainage
system is planned to follow the existing flow patterns as closely as possible. This drainage plan
is not to impact any off-site drainage. Detention is not required for this site as it drains directly
into a regulatory watercourse floodplain and there are no existing land features on-site for storing
and/or detaining stormwater.
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DRAINAGE DESIGN CRITERIA
The entire drainage system for the VPAC Phase IIA is designed for a 10-year storm frequency
and was tested for a 100-year storm frequency. Two prior drainage plans have been prepared
and approved by the City for the VPAC site, one for Phase I and one for Phase II. This plan
assumes that all Above-Project Areas will be designed so as not to change the flows entering the
VPAC. The site will be graded so that all stormwater run-off flows away from any existing or
proposed structures and spreads out over a large area.
The design flows for the project site were calculated using two methods. The flows for areas J-
10 through J-70 were calculated using the Rational Method and WinStorm. The areas, C values,
time of concentration and rainfall intensities were entered into WinStorm to calculate the flows.
The design flows for the culvert were calculated using the Natural Resources Conservation
Service (NRCS) Graphical Peak Discharge Method and checked using the NRCS Tabular
Hydrograph Method. The WinStorm report may be found in Appendix C and the NRCS
Calculations may be found in Appendix D
The stormwater currently travels as sheet flow over land and not in a defined channel, making it
difficult to calculate the existing flow capacity of the site. The storm sewer system is designed
for a flow of 16.18 cfs, the culvert for 263 cfs and the drainage channel is designed for 280 cfs.
The only deviation from the Unified Stormwater Design Guidelines is the slope of the proposed
channel. The existing natural slope of the project site will not allow for a minimum slope of
0.6%.
DRAINAGE SYSTEM DESIGN
Using WinStorm to calculate the flows and design the storm sewer system, the 10-year storm
produces a total out flow of 16.18 cfs. This flow requires a 30-inch outfall pipe into the drainage
channel. A minimum slope of 0.24% will be utilized in the storm sewer system to maintain the
minimum allowable design velocity of 2.5 feet per second (f/s). The maximum velocity
achieved in the WinStorm computations is 4.08 f/s, which is far below the maximum permissible
of 15 f/s. The storm drain conduits were designed for a maximum capacity of 25.95 cfs. The
complete report produced by WinStorm is included in Appendix C, the drainage system design is
located in Appendix E and an electronic version of the analysis is also included with this report.
The NRCS method was utilized to calculate the design flows for the proposed culvert on
Veterans Parkway. The 10-year storm flow was calculated to be 263 cfs entering the culvert.
Using Thysys Culvert, the maximum allowable headwater was set one foot (1 ft.) below the
lowest top of curb at the crossing. The maximum tailwater was set at the soffit of the storm
sewer outfall. Through the use of Thysys it was determined that dual six foot (6 ft.) by three foot
(3 ft.) concrete box culverts would be appropriate to accommodate the 10-year storm. A
discharge velocity of 7.43 f/s was calculated by Thysys. The channel directly following the
culvert will be concrete lined, allowing for a maximum discharge velocity of 15 f/s. The Thysys
report may be referenced in Appendix F.
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The design flows for the storm sewer system and the culvert were added together to design the
drainage channel that they both flow into. A design flow of 280 cfs was used. The Channel
Calculator in Autodesk Land Desktop was used to calculate the required channel cross section.
The channel was designed with a trapezoidal cross section with 4:1 side slopes and an average
channel slope of 0.24%. Due to the existing topography of the project site, a minimum slope of
0.6% is not achievable. A Manning’s Roughness Coefficient of 0.025 was assumed. The
maximum water depth of three feet (3 ft.) was assumed as this is the maximum tailwater of the
culvert. The depth of flow was calculated as 2.93 feet, which is below the maximum three feet
(3 ft.) and allows for a minimum freeboard of one foot (1 ft.). A bottom width of 10 feet was
calculated to be sufficient for the design flow. The calculated velocity of 4.41 f/s is just below
the maximum velocity of 4.5 f/s for a grass surface treatment that is seeded with an erosion mat.
The Channel Calculator report is attached as Appendix G.
All three systems were also tested for a 100-year storm frequency. The 100-year storm flow for
drainage areas J-10 through J-70 is 22 cfs and the storm sewer is designed for a flow capacity of
25.95 cfs; therefore, the storm sewer system can handle the 100-year storm flow created in these
areas. The result for the culvert was a headwater elevation approximately one foot (1’) over the
roadway at the lowest point and a depth of 3.7 feet in the drainage channel. In the event of a 100-
year frequency storm no structures will be damaged as the site grading is designed for the
stormwater to sheet flow over the low point in the road, flowing away from any structures. The
100-year storm reports are in Appendix H.
CONCLUSIONS
The Bryan/College Station Unified Stormwater Design Guidelines were used as a reference
throughout the entire design of this stormwater drainage system. This system was designed to
minimize flooding of the VPAC site and maximum velocities were strictly adhered to so as to
reduce the occurrence of erosion. The stormwater drainage system was designed to effectively
accommodate all flows produced by the fully developed site.
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REFERENCES
Hydraulic Design Manual. Texas Department of Transportation. March 2004.
Unified Stormwater Design Guidelines. City of Bryan and City of College Station. February
2007.
Urban Hydrology for Small Watersheds – TR-55. United States Department of Agriculture –
Natural Resources Conservation Service. June 1986.
APPENDIX A
FEMA MAP NOS. 48041C0161C & 48041C0142C
WITH PROJECT SITE ILLUSTRATED
APPENDIX B
DRAINAGE AREA MAPS
APPENDIX C
WINSTORM REPORT
10-YEAR FREQUENCY STORM
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APPENDIX C
WINSTORM REPORT
10-YEAR FREQUENCY STORM
WinStorm (STORM DRAIN DESIGN) Version 3.05, Jan. 25, 2002
Run @ 6/20/2007 10:42:14 AM
PROJECT NAME : VPAC PH IIA
JOB NUMBER : 675.02PA
PROJECT DESCRIPTION : Storm Sewer Line J 10 YR Design
ANALYSYS FREQUENCY : 10 Years
MEASUREMENT UNITS: ENGLISH
==================================================================================
OUTPUT FOR ANALYSYS FREQUENCY of: 10 Years
=============================================
Runoff Computation for Design Frequency.
=============================================================================
ID C Value Area Tc Tc Used Intensity Supply Q Total Q
(acre) (min) (min) (in/hr) (cfs) (cfs)
-----------------------------------------------------------------------------
J-10 0.45 0.52 10.00 10.00 8.63 0.000 2.020
J-20 0.48 0.46 10.00 10.00 8.63 0.000 1.907
J-30 0.32 2.41 10.00 10.00 8.63 0.000 6.659
J-40 0.47 0.36 10.00 10.00 8.63 0.000 1.461
J-50 0.64 0.16 10.00 10.00 8.63 0.000 0.884
J-60 0.59 0.53 10.00 10.00 8.63 0.000 2.700
J-70 0.62 0.41 10.00 10.00 8.63 0.000 2.195
-----------------------------------------------------------------------------
Sag Inlets Configuration Data.
==================================================================================
Inlet Inlet Length/ Grate Left-Slope Right-Slope Gutter Depth Critic
ID Type Perim. Area Long Trans Long Trans n DeprW Allowed Elev.
(ft) (sf) (%) (%) (%) (%) (ft) (ft) (ft)
----------------------------------------------------------------------------------
J-10 Curb 5.00 n/a 0.60 2.00 0.60 2.00 0.014 1.50 0.50 263.20
J-20 Curb 5.00 n/a 0.60 2.00 0.60 2.00 0.014 1.50 0.50 263.20
J-30 Grate 12.00 3.30 10.00 2.00 10.00 2.00 0.014 n/a 1.00 263.00
J-40 Curb 5.00 n/a 1.00 2.00 1.00 2.00 0.014 1.50 0.50 263.50
J-50 Curb 5.00 n/a 1.00 2.00 1.00 2.00 0.014 1.50 0.50 263.50
J-60 Curb 5.00 n/a 0.60 2.00 0.60 2.00 0.014 1.50 0.50 262.00
J-70 Curb 5.00 n/a 0.60 2.00 0.60 2.00 0.014 1.50 0.50 262.30
----------------------------------------------------------------------------------
Sag Inlets Computation Data.
================================================================================
Inlet Inlet Length Grate Total Q Inlet Total Ponded Width
ID Type Perim Area Capacity Head Left Right
(ft) (ft) (sf) (cfs) (cfs) (ft) (ft) (ft)
--------------------------------------------------------------------------------
J-10 Curb 5.00 n/a n/a 2.020 6.261 0.235 7.55 7.55
J-20 Curb 5.00 n/a n/a 1.907 6.261 0.226 7.40 7.40
J-30 Grate n/a 12.00 3.30 6.659 17.736 0.319 7.00 7.00
J-40 Curb 5.00 n/a n/a 1.461 6.261 0.190 6.10 6.10
J-50 Curb 5.00 n/a n/a 0.884 6.261 0.136 5.05 5.05
J-60 Curb 5.00 n/a n/a 2.700 6.261 0.285 8.45 8.45
J-70 Curb 5.00 n/a n/a 2.195 6.261 0.249 7.80 7.80
--------------------------------------------------------------------------------
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Cumulative Junction Discharge Computations
=================================================================================
Node Node Weighted Cumulat. Cumulat. Intens. User Additional Total
I.D. Type C-Value Dr.Area Tc Supply Q Q in Node Disch.
(acres) (min) (in/hr) cfs) (cfs) (cfs)
---------------------------------------------------------------------------------
J-10 Curb 0.450 0.52 10.00 8.63 0.000 0.00 2.020
J-20 Curb 0.464 0.98 10.14 8.58 0.000 0.00 3.904
J-30 Grate 0.320 2.41 10.00 8.63 0.000 0.00 6.659
J-40 Curb 0.372 3.75 11.48 8.14 0.000 0.00 11.360
J-50 Curb 0.383 3.91 11.57 8.11 0.000 0.00 12.151
J-60 Curb 0.408 4.44 12.33 7.89 0.000 0.00 14.278
J-70 Curb 0.426 4.85 12.51 7.84 0.000 0.00 16.178
j-31 JnctBx 0.362 3.39 10.76 8.37 0.000 0.00 10.264
OUT Outlt 0.426 4.85 12.51 7.84 0.000 0.00 16.178
---------------------------------------------------------------------------------
Conveyance Configuration Data
==================================================================================
Run# Node I.D. Flowline Elev.
US DS US DS Shape # Span Rise Length Slope n_value
(ft) (ft) (ft) (ft) (ft) (%)
----------------------------------------------------------------------------------
10 J-10 J-20 260.73 260.65 Circ 1 0.00 1.25 26.00 0.31 0.013
20 J-20 j-31 260.10 259.82 Circ 1 0.00 2.00 118.00 0.24 0.013
30 J-30 j-31 259.90 259.82 Circ 1 0.00 2.00 26.00 0.31 0.013
31 j-31 J-40 259.32 258.90 Circ 1 0.00 2.50 176.00 0.24 0.013
40 J-40 J-50 258.85 258.77 Circ 1 0.00 2.50 26.00 0.31 0.013
50 J-50 J-60 258.72 257.98 Circ 1 0.00 2.50 221.00 0.33 0.013
60 J-60 J-70 257.93 257.73 Circ 1 0.00 2.50 55.00 0.36 0.013
70 J-70 OUT 257.68 257.60 Circ 1 0.00 2.50 20.00 0.40 0.013
----------------------------------------------------------------------------------
Conveyance Hydraulic Computations. Tailwater = 260.100 (ft)
==================================================================================
Hydraulic Gradeline Depth Velocity Junc
Run# US Elev DS Elev Fr.Slope Unif. Actual Unif. Actual Q Cap Loss
(ft) (ft) (%) (ft) (ft) (f/s) (f/s) (cfs) (cfs) (ft)
----------------------------------------------------------------------------------
10 261.58 261.22 0.098 0.67 0.67 3.00 3.00 2.02 3.58 0.174
20 261.01 260.82 0.030 0.83 1.00 3.18 2.47 3.90 11.02 0.047
30 261.06 260.82 0.087 1.03 1.03 4.08 4.08 6.66 12.55 0.129
31 260.82 260.60 0.063 1.27 1.70 4.10 2.88 10.26 20.04 0.065
40 260.60 260.51 0.077 1.25 1.74 4.63 3.11 11.36 22.76 0.075
50 260.51 260.33 0.088 1.27 2.35 4.85 2.54 12.15 23.74 0.050
60 260.33 260.21 0.121 1.37 2.48 5.20 2.91 14.28 24.74 0.066
70 260.21 260.10 0.156 1.43 2.50 5.59 3.30 16.18 25.95 0.084
===================================END============================================
NORMAL TERMINATION OF WINSTORM.
Warning Messages for current project:
Runoff Frequency of: 10 Years
APPENDIX D
NRCS DRAINAGE CALCULATIONS
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APPENDIX D
NRCS DRAINAGE CALCULATIONS
NRCS GRAPHICAL PEAK DISCHARGE METHOD
TOTAL DRAINAGE AREA, A:
A = 138.4 AC.
0.2163 SQ. MI.
TYPE III RAINFALL DISTRIBUTION
RUNOFF CURVE NUMBER, RCN:
BUSINESS/COMMERCIAL
RCN = 94
A = 14.8 AC.
NATURAL GRASSLANDS/WOODLANDS
RCN = 75
A = 106.1 AC.
IMPERVIOUS AREAS
RCN = 98
A = 17.5 AC.
WEIGHTED AVERAGE
RCN1*A1 + RCN2*A2 + …. RCN = A
RCN = 80
TIME OF CONCENTRATION, Tc:
ASSUME v = 0.75 FT/S FOR GRASS/WOODLAND
ASSUME v = 1 FT/S FOR NATURAL CHANNEL
FROM TABLE C-4 OF
UNIFIED
DIST. TRAVELED Tc = v * 60 * 60 HOURS
Tc = 1.44 HR.
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POTENTIAL MAX. RETENTION, S:
S = z*[(100/RCN)-1]
S = 2.5 IN.
INITIAL ABSTRACTION, Ia:
Ia = 0.2 * S IN.
Ia = 0.50 IN.
ACCUMULATED RAINFALL, P:
FROM TABLE C-6 OF
UNIFIED
24-HR. STORM DURATION
P2 = 4.50 IN.
P5 = 6.20 IN.
P10 = 7.40 IN.
P25 = 8.40 IN.
P50 = 9.80 IN.
P100 = 11.00 IN.
ACCUMULATED DIRECT RUNOFF, R:
R = (P-0.2*S)^2
(P+0.8*S)
R2 = 2.46 IN.
R5 = 3.96 IN.
R10 = 5.06 IN.
R25 = 5.99 IN.
R50 = 7.32 IN.
R100 = 8.47 IN.
UNIT PEAK DISCHARGE, qu:
Ia/P2 = 0.11
Ia/P5 = 0.08
Ia/P10 = 0.07
Ia/P25 = 0.06
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Ia/P50 = 0.05
Ia/P100 =0.05
ONLY THE 2-YEAR STORM FALLS WITHIN BOUNDS OF TABLE
PER TR-55 USE LIMITING VALUE
USE 0.1 LIMIT FOR ALL
USE EXHIBIT 4-III OF TR-55 FOR qu VALUE
qu = 240 CSM/IN
PONDING FACTOR, F:
0% PONDING
F = 1
PEAK DISCHARGE, Q:
Q = quARF
Q2 = 127 CFS
Q5 = 205 CFS
Q10 = 263 CFS
Q25 = 311 CFS
Q50 = 380 CFS
Q100 = 440 CFS
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NRCS TABULAR HYDROGRAPH METHOD
A = 0.2163 SQ. MI.
Tc = 1.44 HR.
RCN = 80
TYPE III
P10 = 7.4 IN.
R10 = 5.06 IN.
TIME
(HRS.)
qt
(CSM/IN.) Q (CFS)
11 3 3.28
12 8 8.76
13 19 20.80
14 103.0 112.73
15 207.0 226.56
16 99.0 108.35
17 54.0 59.10
18 36.0 39.40
19 26.0 28.46
20 20.0 21.89
22 14.0 15.32
26 8.0 8.76
USING TR-55
10-YEAR
UNIT HYDROGRAPH
0
50
100
150
200
250
11 12 13 14 15 16 17 18 19 20 22 26
HYDROGRAPH TIME (HR.)
UN
I
T
D
I
S
C
H
A
R
G
E
(
C
S
M
/
I
N
)
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HYDROGRAPH
0.00
50.00
100.00
150.00
200.00
250.00
11 12 13 14 15 16 17 18 19 20 22 26
HYDROGRAPH TIME (HR.)
DI
S
C
H
A
R
G
E
(
C
F
S
)
APPENDIX E
DRAINAGE SYSTEM DESIGN
APPENDIX F
THYSYS CULVERT REPORT
10-YEAR FREQUENCY STORM
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APPENDIX F
THYSYS CULVERT REPORT
10-YEAR FREQUENCY STORM
TEXAS HYDRAULIC SYSTEM, CULVERT (ver. 1.2. Feb/2002)
Mon Jul 02 11:22:59 2007
CULVERT HYDRAULIC COMPUTATIONS
------------------------------
CULVERT NAME: VPAC Input Units: English
PROJECT NAME: VPAC Output Units: English
PROJECT CONTROL: OE Job No. 675.02 PA
COUNTY: Brazos
DESCRIPTION: VPAC Culvert
ANALYZE MULTIPLE OPENING CULVERT
MATERIAL: CONCRETE
SHAPE: CONCRETE BOX.
ENTRANCE: STRAIGHT
PROFILE: STRAIGHT CULVERT
FREQUENCY: 10-Year DISCHARGE: 263.00 cfs TAILWATER: 260.10 ft
n value: 0.0120 Ke value: 0.7000
CULVERT RISE = 3.00 ft CULVERT SPAN = 6.00 ft BARRELS = 2
INLET station: 0.00 elevation: 257.70 ft
OUTLET station: 106.00 elevation: 257.10 ft
Road profile (XY Coordinates) ft
X Y X Y X Y
19.00 263.40 87.00 263.60
------------------------------------------------------------------------------
------------------------------------------------------------------------------
CULVERT OUTPUT RUN NO => 1
------------------------------------------------------------------------------
ANALYSIS for discharge frequency of : 10-Year
Barls. Qpb Rise Span Length Max.HW Calc.HW HW Control Veloc. Out.depth
elev elev
cfs ft ft ft ft ft ft ft/s ft
------------------------------------------------------------------------------
2 131.50 3.00 6.00 88.00 262.30 262.35 4.70 Inlet 7.43 2.95
Inlet control depth = 4.70 ft
Outlet control depth = 4.85 ft
Normal depth = 2.06 ft Culvert slope = 0.00566
Critical depth = 2.46 ft Critical slope = 0.00345
Road top width => 68.00 ft. Road pavement type => asphalt
Computed Weir Coefficient => 3.00.
No discharge over the road.
------------------------------------------------------------------------------
RUNING MESSAGES LIST:
*Computation: Outlet velocity is based on the tail water depth.
NORMAL TERMINATION OF THYSYS, CULVERT.
APPENDIX G
AUTODESK LAND DESKTOP CHANNEL CALCULATOR REPORT
10-YEAR FREQUENCY STORM
Veterans Park and Athletic Complex – Phase IIA Drainage Report
K:\00675\675-02PA\Report\Appendix G.doc Page 1 of 1
APPENDIX G
AUTODESK LAND DESKTOP CHANNEL CALCULATOR REPORT
10-YEAR FREQUENCY STORM
Channel Calculator
Given Input Data:
Shape ........................... Trapezoidal
Solving for ..................... Depth of Flow
Flowrate ........................ 280.0000 cfs
Slope ........................... 0.0024 ft/ft
Manning's n ..................... 0.0250
Height .......................... 5.0000 ft
Bottom width .................... 10.0000 ft
Left slope ...................... 0.2500 ft/ft (V/H)
Right slope ..................... 0.2500 ft/ft (V/H)
Computed Results:
Depth ........................... 2.9272 ft
Velocity ........................ 4.4063 fps
Full Flowrate ................... 893.9522 cfs
Flow area ....................... 63.5447 ft2
Flow perimeter .................. 34.1380 ft
Hydraulic radius ................ 1.8614 ft
Top width ....................... 33.4173 ft
Area ............................ 150.0000 ft2
Perimeter ....................... 51.2311 ft
Percent full .................... 58.5432 %
Critical Information:
Critical depth .................. 2.1706 ft
Critical slope .................. 0.0082 ft/ft
Critical velocity ............... 6.9049 fps
Critical area ................... 40.5508 ft2
Critical perimeter .............. 27.8989 ft
Critical hydraulic radius ....... 1.4535 ft
Critical top width .............. 27.3644 ft
Specific energy ................. 3.2289 ft
Minimum energy .................. 3.2558 ft
Froude number ................... 0.5633
Flow condition .................. Subcritical
APPENDIX H
100-YEAR FREQUENCY STORM REPORTS
Veterans Park and Athletic Complex – Phase IIA Drainage Report
K:\00675\675-02PA\Report\Appendix H.doc Page 1 of 4
APPENDIX H
100-YEAR FREQUENCY STORM REPORTS
WINSTORM
WinStorm (STORM DRAIN DESIGN) Version 3.05, Jan. 25, 2002
Run @ 6/20/2007 10:55:45 AM
PROJECT NAME : VPAC PH IIA
JOB NUMBER : 675.02PA
PROJECT DESCRIPTION : Storm Sewer Line J 100 YR Check
ANALYSYS FREQUENCY : 100 Years
MEASUREMENT UNITS: ENGLISH
==================================================================================
OUTPUT FOR ANALYSYS FREQUENCY of: 100 Years
=============================================
Runoff Computation for Design Frequency.
=============================================================================
ID C Value Area Tc Tc Used Intensity Supply Q Total Q
(acre) (min) (min) (in/hr) (cfs) (cfs)
-----------------------------------------------------------------------------
J-10 0.45 0.52 10.00 10.00 11.64 0.000 2.724
J-20 0.48 0.46 10.00 10.00 11.64 0.000 2.570
J-30 0.32 2.41 10.00 10.00 11.64 0.000 8.976
J-40 0.47 0.36 10.00 10.00 11.64 0.000 1.969
J-50 0.64 0.16 10.00 10.00 11.64 0.000 1.192
J-60 0.59 0.53 10.00 10.00 11.64 0.000 3.640
J-70 0.62 0.41 10.00 10.00 11.64 0.000 2.959
-----------------------------------------------------------------------------
Sag Inlets Configuration Data.
==================================================================================
Inlet Inlet Length/ Grate Left-Slope Right-Slope Gutter Depth Critic
ID Type Perim. Area Long Trans Long Trans n DeprW Allowed Elev.
(ft) (sf) (%) (%) (%) (%) (ft) (ft) (ft)
----------------------------------------------------------------------------------
J-10 Curb 5.00 n/a 0.60 2.00 0.60 2.00 0.014 1.50 0.50 263.20
J-20 Curb 5.00 n/a 0.60 2.00 0.60 2.00 0.014 1.50 0.50 263.20
J-30 Grate 12.00 3.30 10.00 2.00 10.00 2.00 0.014 n/a 1.00 263.00
J-40 Curb 5.00 n/a 1.00 2.00 1.00 2.00 0.014 1.50 0.50 263.50
J-50 Curb 5.00 n/a 1.00 2.00 1.00 2.00 0.014 1.50 0.50 263.50
J-60 Curb 5.00 n/a 0.60 2.00 0.60 2.00 0.014 1.50 0.50 262.00
J-70 Curb 5.00 n/a 0.60 2.00 0.60 2.00 0.014 1.50 0.50 262.30
----------------------------------------------------------------------------------
Sag Inlets Computation Data.
================================================================================
Inlet Inlet Length Grate Total Q Inlet Total Ponded Width
ID Type Perim Area Capacity Head Left Right
(ft) (ft) (sf) (cfs) (cfs) (ft) (ft) (ft)
--------------------------------------------------------------------------------
J-10 Curb 5.00 n/a n/a 2.724 6.261 0.287 8.45 8.45
J-20 Curb 5.00 n/a n/a 2.570 6.261 0.276 8.30 8.30
J-30 Grate n/a 12.00 3.30 8.976 17.736 0.389 7.80 7.80
J-40 Curb 5.00 n/a n/a 1.969 6.261 0.231 6.80 6.80
J-50 Curb 5.00 n/a n/a 1.192 6.261 0.165 5.65 5.65
J-60 Curb 5.00 n/a n/a 3.640 6.261 0.348 9.45 9.45
J-70 Curb 5.00 n/a n/a 2.959 6.261 0.303 8.75 8.75
--------------------------------------------------------------------------------
Veterans Park and Athletic Complex – Phase IIA Drainage Report
K:\00675\675-02PA\Report\Appendix H.doc Page 2 of 4
Cumulative Junction Discharge Computations
=================================================================================
Node Node Weighted Cumulat. Cumulat. Intens. User Additional Total
I.D. Type C-Value Dr.Area Tc Supply Q Q in Node Disch.
(acres) (min) (in/hr) cfs) (cfs) (cfs)
---------------------------------------------------------------------------------
J-10 Curb 0.450 0.52 10.00 11.64 0.000 0.00 2.724
J-20 Curb 0.464 0.98 10.14 11.58 0.000 0.00 5.265
J-30 Grate 0.320 2.41 10.00 11.64 0.000 0.00 8.976
J-40 Curb 0.372 3.75 11.36 11.04 0.000 0.00 15.397
J-50 Curb 0.383 3.91 11.45 11.00 0.000 0.00 16.473
J-60 Curb 0.408 4.44 12.15 10.72 0.000 0.00 19.404
J-70 Curb 0.426 4.85 12.32 10.66 0.000 0.00 21.997
j-31 JnctBx 0.362 3.39 10.70 11.32 0.000 0.00 13.878
OUT Outlt 0.426 4.85 12.32 10.66 0.000 0.00 21.997
---------------------------------------------------------------------------------
Conveyance Configuration Data
==================================================================================
Run# Node I.D. Flowline Elev.
US DS US DS Shape # Span Rise Length Slope n_value
(ft) (ft) (ft) (ft) (ft) (%)
----------------------------------------------------------------------------------
10 J-10 J-20 260.73 260.65 Circ 1 0.00 1.25 26.00 0.31 0.013
20 J-20 j-31 260.10 259.82 Circ 1 0.00 2.00 118.00 0.24 0.013
30 J-30 j-31 259.90 259.82 Circ 1 0.00 2.00 26.00 0.31 0.013
31 j-31 J-40 259.32 258.90 Circ 1 0.00 2.50 176.00 0.24 0.013
40 J-40 J-50 258.85 258.77 Circ 1 0.00 2.50 26.00 0.31 0.013
50 J-50 J-60 258.72 257.98 Circ 1 0.00 2.50 221.00 0.33 0.013
60 J-60 J-70 257.93 257.73 Circ 1 0.00 2.50 55.00 0.36 0.013
70 J-70 OUT 257.68 257.60 Circ 1 0.00 2.50 20.00 0.40 0.013
----------------------------------------------------------------------------------
Conveyance Hydraulic Computations. Tailwater = 260.100 (ft)
==================================================================================
Hydraulic Gradeline Depth Velocity Junc
Run# US Elev DS Elev Fr.Slope Unif. Actual Unif. Actual Q Cap Loss
(ft) (ft) (%) (ft) (ft) (f/s) (f/s) (cfs) (cfs) (ft)
----------------------------------------------------------------------------------
10 261.75 261.39 0.178 0.82 0.82 3.19 3.19 2.72 3.58 0.198
20 261.39 261.29 0.054 0.97 1.47 3.49 2.13 5.26 11.02 0.035
30 261.43 261.29 0.157 1.25 1.47 4.35 3.63 8.98 12.55 0.102
31 261.29 261.04 0.114 1.52 2.14 4.43 3.10 13.88 20.04 0.075
40 261.04 260.93 0.141 1.52 2.16 4.92 3.42 15.40 22.76 0.091
50 260.93 260.55 0.161 1.52 2.50 5.26 3.36 16.47 23.74 0.088
60 260.55 260.31 0.224 1.68 2.50 5.53 3.95 19.40 24.74 0.121
70 260.31 260.10 0.288 1.76 2.50 5.96 4.48 22.00 25.95 0.156
===================================END============================================
NORMAL TERMINATION OF WINSTORM.
Warning Messages for current project:
Runoff Frequency of: 100 Years
Veterans Park and Athletic Complex – Phase IIA Drainage Report
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THYSYS CULVERT
TEXAS HYDRAULIC SYSTEM, CULVERT (ver. 1.2. Feb/2002)
Mon Jul 02 11:31:53 2007
CULVERT HYDRAULIC COMPUTATIONS
------------------------------
CULVERT NAME: 100-year Input Units: English
PROJECT NAME: VPAC - 100 yr. Output Units: English
PROJECT CONTROL: OE 675.02 PA
COUNTY: Brazos
DESCRIPTION: 100-year Flow Analysis
ANALYZE MULTIPLE OPENING CULVERT
MATERIAL: CONCRETE
SHAPE: CONCRETE BOX.
ENTRANCE: STRAIGHT
PROFILE: STRAIGHT CULVERT
FREQUENCY: 100-year DISCHARGE: 440.00 cfs TAILWATER: 260.80 ft
n value: 0.0120 Ke value: 0.7000
CULVERT RISE = 3.00 ft CULVERT SPAN = 6.00 ft BARRELS = 2
INLET station: 0.00 elevation: 257.70 ft
OUTLET station: 106.00 elevation: 257.10 ft
Road profile (XY Coordinates) ft
X Y X Y X Y
19.00 263.40 87.00 263.60
------------------------------------------------------------------------------
------------------------------------------------------------------------------
CULVERT OUTPUT RUN NO => 1
------------------------------------------------------------------------------
ANALYSIS for discharge frequency of : 100-year
Barls. Qpb Rise Span Length Max.HW Calc.HW HW Control Veloc. Out.depth
elev elev
cfs ft ft ft ft ft ft ft/s ft
------------------------------------------------------------------------------
2 171.02 3.00 6.00 88.00 262.30 264.10 6.45 Inlet 9.50 3.00
Inlet control depth = 6.45 ft
Outlet control depth = 6.05 ft
Normal depth = 2.49 ft Culvert slope = 0.00566
Critical depth = 2.93 ft Critical slope = 0.00364
Road top width => 68.00 ft. Road pavement type => asphalt
Computed Weir Coefficient => 3.03.
Toal Discharge => 440.00 cfs
Discharge per barrel => 171.02 cfs
Discharge over the road => 97.97 cfs
Average velocity over the road => 2.35 ft/sec
------------------------------------------------------------------------------
RUNING MESSAGES LIST:
NORMAL TERMINATION OF THYSYS, CULVERT.
Veterans Park and Athletic Complex – Phase IIA Drainage Report
K:\00675\675-02PA\Report\Appendix H.doc Page 4 of 4
AUTODESK LAND DESKTOP - CHANNEL CALCULATOR
Channel Calculator
Given Input Data:
Shape ........................... Trapezoidal
Solving for ..................... Depth of Flow
Flowrate ........................ 462.0000 cfs
Slope ........................... 0.0024 ft/ft
Manning's n ..................... 0.0250
Height .......................... 5.0000 ft
Bottom width .................... 10.0000 ft
Left slope ...................... 0.2500 ft/ft (V/H)
Right slope ..................... 0.2500 ft/ft (V/H)
Computed Results:
Depth ........................... 3.7043 ft
Velocity ........................ 5.0256 fps
Full Flowrate ................... 893.9522 cfs
Flow area ....................... 91.9295 ft2
Flow perimeter .................. 40.5463 ft
Hydraulic radius ................ 2.2673 ft
Top width ....................... 39.6342 ft
Area ............................ 150.0000 ft2
Perimeter ....................... 51.2311 ft
Percent full .................... 74.0856 %
Critical Information:
Critical depth .................. 2.8197 ft
Critical slope .................. 0.0076 ft/ft
Critical velocity ............... 7.7002 fps
Critical area ................... 59.9988 ft2
Critical perimeter .............. 33.2516 ft
Critical hydraulic radius ....... 1.8044 ft
Critical top width .............. 32.5573 ft
Specific energy ................. 4.0968 ft
Minimum energy .................. 4.2295 ft
Froude number ................... 0.5818
Flow condition .................. Subcritical
APPENDIX I
OVERALL SITE LAYOUT
APPENDIX J
PENDING TxDOT PERMIT
Permit to Construct Access Driveway Facilities
on Highway Right of Way
To: City of College Station Hwy. FM 60 Permit No.
(Name)
1101 Texas Ave. Control Section
(Address)
College Station, Texas 77840-2499 (979) 764-3500
(City, State, Zip) (Phone No.)
The Texas Department of Transportation, hereinafter called the State, hereby authorizes
City of College Station
,
hereinafter called the Permittee, to construct / reconstruct a Park Entrance Road (residential, convenience
store, retail mall, farm, etc.) access driveway on the highway right of way abutting highway number FM 60 in Brazos
County, located CSJ: 0506-01-082, Sta. +/- 26+20 .
Subject to the following:
1. The Permittee is responsible for all costs associated with the construction of this access driveway.
2. Design of facilities shall be as follows and/or as shown on sketch and is subject to conditions stated below:
Construct a Park Entrance Road (see attached sketch for more details).
All construction and materials shall be subject to inspection and approved by the State.
3. Maintenance of facilities constructed hereunder shall be the responsibility of the Permittee, and the State reserves the right to
require any changes, maintenance or repairs as may be necessary to provide protection of life or property on or adjacent to
the highway. Changes in design will be made only with approval of the State.
4. The Permittee shall hold harmless the State and its duly appointed agents and employees against any action for personal
injury or property damage sustained by reason of the exercise of this permit.
5. Except for regulatory and guide signs at county roads and city streets, the Permittee shall not erect any sign on or extending
over any portion of the highway right of way, and vehicle service fixtures such as fuel pumps, vendor stands, or tanks shall be
located at least 12 feet from the right of way line to ensure that any vehicle services from these fixtures will be off the highway
right of way.
6. The State reserves the right to require a new access driveway permit in the event of a land use change or change in driveway
traffic volume or vehicle types.
7. This permit will become null and void if the above-referenced driveway facilities are not constructed within six (6) months from
the issuance date of this permit.
8. The Permittee will contact the State’s representative Walter Norwood, Brazos County Maintenance Supervisor
telephone, (979 ) 778-8054 , at least twenty-four (24) hours prior to beginning the work authorized by this permit.
Texas Department of Transportation
Date of Issuance Authorized Representative
The undersigned hereby agrees to comply with the terms and conditions set forth in this permit for construction of an access
driveway on the highway right of way.
Date:
Signed:
(Property owner or owner’s representative)
Form 1058
(Rev. 9/2004)
(GSD-EPC)
Page 1 of 2
Form 1058
(Rev. 9/2004) Page 2 of 2
Access Driveway Regulations
The Texas Transportation Commission, in recognition of its responsibility for the safety and utility of public highways under its
jurisdiction, has directed the department to adopt access driveway standards to accomplish a coordinated development between
highways and abutting property. For this purpose, the booklet entitled “Regulations for Access Driveways to State Highways”, was
published and adopted, setting out departmental policies to regulate construction and maintenance of access driveway facilities.
_____________________________________________________________________________________________
Sketch of Installation