HomeMy WebLinkAboutFinal Drainage ReportN 0<'"91!3~
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FINAL DRAINAGE REPORT
FOR
COLLEGE STATION MEDICAL CENTER
1604 ROCK PRAIRIE ROAD
COLLEGE STATION, TX 77842
College Station, Brazos County, Texas
October, 2001
REVIEWED FOR
~ COf\~PLl .l\ ~·'CE
NOV 2 0 2001
COLLEGE s i A I IUi'J
ENGINEERING ,c'\\J. 255 l Texas Ave. SouU1, Ste. A, College Sration. TX 77840 ~
'"''-l~f Ofc: 979.693.5359 Fa-.:: 979.693.4243 Email : mdgcs@mdgcs.com Web: www.mdgcs.com
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TABLE OF CONTENTS
1.0 PROJECT SCOPE. ................................................................................................ 1
1.1 SITE LOCATION .................................................................................................... 1
1.2 GENERAL DESCRIPTION .................................................................................... 1
1.3 FEMA INFORMATION .......................................................................................... 2
2.0 DRAINAGE BASINS & SUB-BASINS ................................................................. 2
2.1 MAJOR DRAINAGE BASIN DESCRIPTIONS ...................................................... 2
2.2 SUB-DRAINAGE BASIN DESCRIPTIONS ........................................................... 2
3.0 DRAINAGE DESIGN CRITERIA & CONSTRAINTS ....................................... 3
3 .1 DETENTION FACILITIES ..................................................................................... 4
3.2 EROSION & SEDIMENTATION CONTROL ........................................................ 4
4.0 HYDROLOGY & HYDRAULICS MODELING ................................................. 5
4.1 HYDROLOGY ........................................................................................................ 5
4.2 DETENTION FACILITIES ..................................................................................... 6
5.0 CONCLUDED DRAINAGE IMPROVEMENTS ................................................ 6
5.1 DETENTION FACILITIES ..................................................................................... 6
5.2 ON-SITE STORM SEWER SYSTEMS ................................................................... 7
5.3 EROSION & SEDIMENTATION CONTROL ........................................................ 9
APPENDIX A -EXHIBITS
APPENDIX B -HYDROLOGY & HYDRAULIC COMPUTATIONS
REVIEWED FOR
Cf'" '101 11\ ~.!CE
NOV 2 0 2001
COLLEGt: ~, r. i 1ui\J
ENGINEERING
ii
LIST OF TABLES
DESCRIPTION PAGE NO.
TABLE #1 : RunoffData ................................................................................................ 5
TABLE #2 : On-Site Runoff Detention ........................................................................... 6
TABLE #3 : Pilot Channel Results .................................................................................. 7
TABLE #4 : On-Site Storm Sewer (Inlets) ...................................................................... 8
TABLE #5 : On-Site Storm Sewer (Conveyance) ............................................................ 9
iii
College Station Medical Center
Medical Office Building II
1.0 PROJECT SCOPE
Municipal Development Group
This report outlines the drainage improvements for the development of the
College Station Medical Center, Medical Office Building II and the anticipated
development of associated parking, stormwater runoff and detention facility
improvements. This drainage report will address the requirements necessary for
all proposed improvements pertinent to this development in accordance with the
provisions of the City of College Station Drainage Policy and Design Standards.
1.1 SITE LOCATION
The proposed improvements are located and contained solely within the
Belmont Place Subdivision, Section Two, Tract A of Block Three.
Particularly, the proposed MOB II will be constructed between the
existing hospital building and the existing MOB. The hospital site and
development area is bordered by Rock Prairie Road, Longmire Drive and
Birmingham Road. These roads are classified as major arterial, major
collector and minor collector respectively. Surrounding existing
developments immediately adjacent and neighboring to the project site
are; City of College Station Utility Service Center to the west, the Center
American (Krogers) Shopping Center to the east, and College Station
Professional Building to the immediate north. The project site area is
graphically illustrated on Exhibit #1 -"General Location Map" located in
Appendix A -Exhibits.
1.2 GENERAL DESCRIPTION
The Belmont Place, Section Two, Block Three, Tract A is a 25 .00 acre
tract, which contains the College Station Medical Center. Also, adjacent
to this tract is an unplatted 0.44 acre parcel of land that is owned by the
hospital. Development will not occur on this property at this time. The
project site is partially developed with buildings, parking, detention
facilities, and associated landscaping. Unimproved areas contain native
grasses and weeds with scattered trees. The site's current conditions are
000727-3376 Drainage Report Final Drainage Report - 1
College Station Medical Center
Medical Office Building II Municipal Development Group
illustrated on Exhibit #2 -"Existing Site Plan" and are located in
Appendix A -Exhibits.
1.3 FEMAINFORMATION
No portions of the project site is located within the 100-year floodplain as
shown on the Federal Emergency Management Agency's, Flood Insurance
Rate Map, (FIRM) Map Panel No. 48041 201D having an effective date of
February 9, 2000. An excerpt of the FIRM map with the location of the
project site is illustrated on Exhibit #3 -"FIRM Map" which is located in
Appendix A -Exhibits.
2.0 DRAINAGE BASINS & SUB-BASINS
2.1 MAJOR DRAINAGE BASINS
The drainage improvements project site 1s contained within two (2)
primary watersheds. Approximately, the upper northwest corner of the
site is contained within the watershed of Bee Creek. This drainage basin
is illustrated in its entirety on Exhibit #4 -"Bee Creek Drainage Basin".
The remaining southeast portion of the property is contained within the
drainage area of Lick Creek. This watershed is illustrated on Exhibit #5 -
"Lick Creek Drainage Basin". Both exhibits are provided in Appendix A
-Exhibits.
2.2 SUB-DRAINAGE BASINS
As discussed previously, this development is contained within two (2)
watersheds, which drain to the northwest (Bee Creek Watershed) and to
the southeast (Lick Creek Watershed). Detention facilities for each of
these watersheds were surveyed and pond volumes then calculated. The
existing drainage conditions for the site and each specific sub-drainage
basin are graphically illustrated on Exhibit #6 -"Pre-Development
Drainage Basin Map" and are explained in more detail as follows. From
000727-3376 Drainage Report Final Drainage Report -2
College Station Medical Center
Medi cal Office Building II Municipal Development Group
these pre-development drainage basis, runoff calculations will be
performed and used as the basins for detention storage calculations.
•:• Runoff from approximately 8.02 acres within the College Station
Medical Center's most northwesterly corner drains into an existing
detention pond (called Bee Creek detention facility). This pond
has an existing storage volume of approximately 13,300 cubic-feet.
Runoff is metered out of the pond and then conveyed under Rock
Prairie Road in a 48" RCP to the north. Thence runoff continues
through an improved drainage channel located in the Southwood
Valley and ultimately to Tributary "A" of Bee Creek;
•:• Runoff from approximately 12.87 acres of the College Station
Medical Center's southeast portion drains into an existing
detention pond (called Lick Creek detention facility). This pond
has an existing storage volume of approximately 50,835 cubic-feet.
Runoff is metered out by sheet flow onto Birmingham Road.
Thence, runoff is carried in the street's gutter to the west, through a
30" RCP, along an improved channel adjacent to Costa! Drive and
to the confluence of the North Fork Lick Creek.
Next, these sub-drainage basins were reconfigured to match drainage
patterns of the proposed site grading. New coefficients of runoff were
established with associated runoff values. From these computations the
existing detention facilities were analyzed and expansion requirements
determined. The proposed sub-drainage basins are illustrated on Exhibit
#7 -"Post-Development Drainage Basin Map" which is contained within
Appendix A-Exhibits.
In addition to detention facility evaluations, the existing storm sewer
systems and proposed improvements were evaluated for adequate sizing
and proposed expansion. Based from proposed grading Exhibit #8 -
"Post-Development Drainage Sub-Areas Map" was generated. From this
000727-3376 Drainage Report Final Drainage Report -3
College Station Medical Center
Medical Office Building II Municipal Development Group
data all existing systems will be evaluated and proposed inlets and
conveyance systems design. This exhibit is contained within Appendix A
-Exhibits.
3.0 DRAINAGE DESIGN CRITERIA & CONSTRAINTS
For all development within the City of College Station, there are criteria on the
use of which design storms and development conditions for each type of public
drainage improvements. Below, for each type of applicable public drainage
improvement, the required design constraints are more fully detailed. All
drainage improvements shall also be analyzed during the 100-year rainfall event
to insure that no adverse conditions will exist.
3 .1 DETENTION
Detention shall be designed in accordance to the City of College Station's
Drainage Policy and Design Standards. Unless otherwise stated, the
following constraints shall dictate the design of detention basins:
•:• Detention facilities shall have the capacity to contain the 100-year
rainfall event.
•:• Maximum detention basin's side slope shall be 4: 1 with vegetative
cover and 2: 1 for non-vegetative cover.
•:• Bottom slopes of the detention basin with vegetative cover shall be at a
grade of 20: 1 with low-flow pilot channels.
•:• Minimum of 0.5 feet of freeboard during the 100-year rainfall event.
•:• Detention facilities other than parking lots and rooftops shall have an
increased capacity of 10% to allow for sedimentation.
3.2 EROSION & SEDIMENTATION CONTROL
Erosion and sedimentation control measures shall be implemented in
accordance to the City of College Station's Drainage Policy and Design
Standards. Temporary and permanent erosion control features shall be
incorporated into the project site at key locations to control concentrated
and overland flows. As a part of the Grading and Drainage Plan, an
Erosion Control Plan is provided with appurtenant details and for all
developments of five (5) acres or more shall issue an Environmental
000727-3376 Drainage Report Final Drainage Report - 4
College Station Medical Center
Medical Office Building II Municipal Development Group
Protection Agency Notice of Intent (EPA-NOI) with a Storm Water
Pollution Prevention Plan (SWPPP).
4.0 HYDROLOGY & HYDRAULICS MODELING
4.1 HYDROLOGY
Determination of runoff quantities was made by the Rational Method. The
Rational Method (Q=CIA) is a simple, yet accurate hydrologic formula for
drainage basins of 100-acres or Jess. The four components of the equation
are described as follows:
•:• Q = The discharge runoff in cubic feet per second;
•:• C = The runoff coefficient for the drainage basin;
•:• I = The storm intensity in inches per hour for each selected
frequency and taken from an intensity-duration-frequency curve at
a Time of Concentration (Tc) for the particular county. A
minimum of 10 minutes for all calculations will be used;
•:• A = The total area of the drainage basin in acres.
For each of these sub-drainage basins the 2, 5, 10, 25, 50 & 100-year
rainfall events were analyzed. These values are as illustrated below in
Table #1 -"Runoff Data".
X1 14.19
X2 17.44
P1 27.00
P2 19.84
000727-3376 Drainage Report
TABLE#l
RUNOFF DATA
RATIONAL METHOD
17.25 19.36
21 .21 23.80
32.83 36.85
24.13 27.08
22.11 25.00 26.10
27.19 30.73 32.09
42.09 47.57 49.67
30.93 34.96 36.51
Final Drainage Report -5
College Station Medical Center
Medical Office Building II Municipal Development Group
4.2 DETENTION FACILITIES
Detention requirements are determined by graphical means. Tabulations of
the pre-development and the post-development hydrographs of the
drainage areas are provided. The hydrographs are based on the standard
SCS unit hydrograph with time to peak discharge set to equal the time of
concentration and the total base time set at 3. 00 times the time of
concentration.
5.0 CONCLUDED DRAINAGE IMPROVEMENTS
Below are the concluded drainage improvements for the College Station Medical
Center proposed Medical Office Building II.
5.1 DETENTION FACILITIES
Detention of increased runoff ts required for all development m
accordance with the City of College Station's Drainage Policy and Design
Standards. By a comparison of the pre and post-development hydro graphs
a required detention volume determination was obtained for each of the
two drainage watersheds. These detention volume improvements are as
summarized below in Table #2 -"On-Site Runoff Detention":
TABLE #2 -ON-SITE RUNOFF & DETENTION
!•II •li BEE CREEK DENTENTION FACILITY
2 14.19 27.00 12.81
5 17.25 32.83 15.58
10 19.36 36.85 17.49
25 22.11 42.09 19.97
50 25.00 47.57 22.58
100 26.10 49.67 23.57
LICK CREEK DENTENTION FACILITY
2 17.44 19.84 2.40
5 21 .21 24.13 2.92
10 23.80 27.08 3.28
25 27.19 30.93 3.74
50 30.73 34.96 4.23
100 32.09 36 .51 4.42
000727-3376 Drainage Report
11,532
14,021
15,737
17,975
20,318
21 ,215
2,162
2,628
2,950
3,369
3,808
3,976
Final Drainage Report -6
College Station Medical Center
Medical Office Building II Municipal Development Group
As reflected in Table #2, the Bee Creek detention facility will need to be
expanded from its existing volume of 13 ,300 cubic-feet to a total volume
of 37,696 cubic-feet. This number is derived from the increased runoff
plus an additional 10% for sedimentation and 5% for a factor of safety
then the addition of the existing storage volume. The expansion of this
pond and associated improvements are illustrated on Exhibit #9 -"Bee
Creek Detention Facility Improvements Plan", located in Appendix A-
Exhibits.
Also, illustrated in Table #2 is the increased runoff for the Lick Creek
watershed. As shown this sub-drainage basin only incurs an increased
runoff amount of 4.42 cfs during the 100-year rainfall event, which
equates to an increased storage need of 3,976 cubic-feet. This volume is
being considered a negligible amount based from the total pond volume
and therefore no proposed improvements will be planned for the Lick
Creek detention facility for the MOB II improvements.
As required by ordinance, all detention ponds shall have a low-flow pilot
channel installed. Since improvements are being made to the Bee Creek
detention pond it will be brought up to city ordinances. As a rule-of-
thumb for design purposes the low-flow pilot channel shall meet the
design capacities fo r open-channel conditions. Therefore, low-flow pilot
channel widths shall be sized to carry one-third of the 5-year rainfall
event. For each outlet into the pond, the contributing sub-drainage areas'
runoff was used which is illustrated on Exhibit #8 -"Post-Development
Drainage Sub-Areas Map". Design results for these pilot channels for
each detention pond's sub-drainage areas are summarized below in Table
#3 -"Pilot Channel Results":
000727-3376 Drainage Report Final Drainage Report - 7
College Station Medical Center
Medical Office Building II Municipal Development Group
TABLE #3-PILOT CHANNEL RESULTS
iil•i•lillti&llii
A1
81
C1&2
Bee Creek Detention Facility
2.50 3.39
6.70 5.30
6.80 5.33
4.00
5.00
5.00
0.6
-0.3
-0.3
It should also be noted that this pond's existing outlet structure will be
utilized and only extended on the upstream end as required by the
proposed expansion improvements. Therefore, no evaluation of the
pond's outlet structure will be made since it will remain in place.
5.2 ON-SITE STORM SEWER SYSTEMS
Due to expansion of on-site parking, reconfiguring of the maintenance
building parking area, and addition of the MOB II roof drains the on-site
storm sewer system required some minor upgrades, extensions and
additions. The proposed improvements are illustrated on Exhibit #10 -
"On-Site Storm Sewer Improvements Plan". Hydraulic design was based
from the IO-year rainfall event and analyzed during the 100-year event.
The results are as summarized below in Table #4 & #5:
TABLE #4 -ON-SITE STORM SEWER (INLETS)
••1n11•111•r•
000727-3376 Drainage Report
A1
C1
A1
C1
10-YEAR RAINFALL EVENT
8.32 5.0 15.20
15.23 8.0 24.33
100-YEAR RAINFALL EVENT
11 .21 5.0 15.20
20.53 8.0 24.33
0.66
0.73
0.81
0.88
Final Drainage Report - 8
College Station Medical Center
Medical Office Building II Municipal Development Group
TABLE #4 -ON-SITE STORM SEWER (CONVEYANCE)
li•1illllll•il11Etllili
A1
C1
C2
C3
C4
01
A1
C1
C2
C3
C4
01
10-YEAR RAINFALL EVENT
18 8.32 12.13
24 21 .71 18.93
18 7.55 8.58
18 7.55 8.71
18 7.55 9.10
12 3.55 N/A
100-YEAR RAINFALL EVENT
18 11.21 12.13
24 29.37 18.93
18 10.17 8.58
18 10.17 8.71
18 10.17 9.10
12 4.79 N/A
5.3 EROSION & SEDIMENTATIO CONTROL
5.3. l TEMPORARY CONTROL MEASURES
4.71
6.91
4.27
4.27
4.27
3.47
6.34
9.35
5.76
5.76
5.76
3.61
As depicted on Exhibit #11 -"Grading, Drainage & Erosion Control
Plan", located in Appendix A -Exhibits, silt fencing will be installed at
key locations prior to construction. This silt fencing will remain and be
maintained through the duration of construction and to a point in time after
construction when sufficient groundcover has been established. Silt
fencing will be installed to prohibit siltation from entering Rock Prairie
Road and neighboring properties.
5. 3 .2 PERMANENT C ONTROL MEASURES
As a standard practice, all disturbed areas will be seeded when final grades
are meet. Seeded areas shall be fertilized and irrigated to stimulate prompt
growth of the seasonal vegetation.
000727-3376 Drainage Report Final Drainage Report -9
000727-3376 Drainage Report
APPENDIX A
EXHIBITS
DESCRIPTION
APPENDIX A
TABLE OF CONTENTS
PAGE NO.
Exhibit #1 -General Location Map ............................................................................. A-1
Exhibit #2 -Existing Site Plan .................................................................................... A-2
Exhibit #3 -FIRM Map .............................................................................................. A-3
Exhibit #4 -Bee Creek Drainage Basin ....................................................................... A-4
Exhibit #5 -Lick Creek Drainage Basin ...................................................................... A-5
Exhibit #6 -Pre-Development Drainage Basin Map .................................................... A-6
Exhibit #7 -Post-Development Drainage Basin Map .................................................. A-7
Exhibit #8 -Post-Development Sub-Areas Map .......................................................... A-8
Exhibit #9 -Bee Creek Detention Facility Improvements Plan .................................... A-9
Exhibit #10 -On-Site Storm Sewer Improvements Plan ............................................ A-10
Exhibit #11 -Grading, Drainage & Erosion Control Plan .......................................... A-11
000727-3376 Drainage Report
RM 51 285. 78
RM 52 296 .15
PROJECT SITE
ELEVATION REFERENCE I\
DESCRIPTION OF LC
Railroad spike set in
located on the south s
6 at Lick Creek.
From the intersection
and Rock Prairie Road,
o.9 mile to the inters
Prairie Road and Bird
spike is in power pole
approximately 34.0 fee
Road.
-NATIONAL FLOOD INSURANCE PROGRAM
I
I .
FIRM
FLOOD IKSURANCE RATE MAP
BRAZOS COUNTY,
TEXAS AND
INCORPORATED AREAS
(SEE MAP INDEX FOR PANELS NOT PRINTED)
com1Hs:
COMMUNITY
COLLEGE STATION. CITY OF 480083 0201 D
UNINCORPORATED AREAS 481195 0201 D
Notice To Us«: The MAP NUMBER shown below should De used
when piecing map orders; ltl• COMMUNITY NUMBER shown
above should be used on insurance applications for the subject
communrty.
MAP NUMBER
48041C0201 D
:I I -I 44:-Y M-il\~ '.l.?~--...,:1,_;;.,, 1;1~ •:....0 = -~
MAP REVISED:
FEBRUARY 9, 2000 ~~~)
11\, ':{J, EXHIBIT #3 -FIRM MAP
11 Federal Emergency Management Agency
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TO
HUNTSVILLE
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PROJECT SITE
_;
2551 TEXAS AVEl'l..IE SOUTH. SUTE A
COLLEGE STATION. T1C n &4-0
Ph: (979) 693-5359
Fx(979)~43
E~IL: mdgcs@mdgcs.com
WEB: www.mdgcs.com
£\"GINEERS. CONSULT ANTS, MANAGERS
EXHIBIT #1
GENERAL LOCATION MAP
FOR
COLLEGE STATION MEDICAL CENTER
MEDICAL OFFICE BUILDING II
BELMONT PLACE, SECTION TWO
TRACT A, BLOCK TWO
RICHARD CARTER LEAGUE. ABSTRACT No. 6
COLLEGE STATION. BRAZOS OOUNTY. TEXAS
Prepared for the exclusive use of:
COLLEGE STATION MEDICAL CENTER
(979) 764-5100
Scale: 1" = 2 Ml. Sheet: 1 of 1
Date: NOVEMBER, 2001
Drawn By: SWW
M.D.G. No. 000727-3376 A-1
APPENDIXB
HYDROLOGY & HYDRAULIC COMPUTATION
000727-3376 Drainage Report
DESCRIPTION
APPENDIXB
TABLE OF CONTENTS
PAGE NO.
Rational Calculations (Pre-Development) (Bee Creek) ................................................ B-1
Rational Calculations (Pre-Development) (Lick Creek) ............................................... B-2
Rational Calculations (Post-Development) (Bee Creek) .............................................. B-3
Rational Calculations (Post-Development) (Lick Creek) ............................................. B-4
Runoff Hydrographs (Bee Creek) ................................................................................ B-5
Runoff Hydro graphs (Lick Creek) ............................................................................... B-6
Pilot Channel Calculations (Bee Creek) ....................................................................... B-7
THSYS Calculations (Sub-Drainage Area "A") ........................................................... B-8
THSYS Calculations (Sub-Drainage Area "C") ........................................................... B-9
Rational Calculations (Sub-Drainage Area "D") ........................................................ B-10
THSYS Calculations (Sub-Drainage Area "D") ......................................................... B-11
000727-3376 Drainage Report
RATIONAL CALCULATIONS: PRE-DEVELOPMENT (BEE CREEK)
GENERAL INFORMATION RESULT
Description: Drainage area of site before proposed development.
Drainage Area (AiMPERv1ous) = 3.61 acres
Drainage Area (ALANDSCAPED) =
Drainage Area (AuNDEVELOPED) =
TIME OF CONCENTRATION (Tel
GIVEN
Max. Travel Distance (DPRE) =
Velocity of Runoff (VPRE) =
**NOTE: Minimum Tc allowed = 10 min.
RUNOFF COEFFICIENTS
Runoff Coefficient (C1MPERv1ous) =
Runoff Coefficient (CLANoscAPEo) =
2.06 acres
2.35 acres
500 ft
1.50 1\ec
0.95
0.30
Runoff Coefficient (CuNDEVELOPED) = 0.38
2 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient ( d) =
0.806
65
8
5 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) = 0.785
Coefficient (b) = 76
Coefficient ( d) = 8.5
10 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) = 0.763
Coefficient (b) = 80
Coefficient ( d) = 8.5
25 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient ( d) =
0.754
89
8.5
50 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient ( d) =
0.745
98
8.5
100 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient ( d) =
000727-3376 Rational Calcul ations-Bee Creek
0.73
96
8
Total Drainage Area (X1) =
Tc(PRE) =
Wtd. Runoff Coefficient (Cwro) :
Rainfall Intensity (1 2) =
Rainfall Intensity (15) =
Rainfall Intensity (1 10) =
Rainfall Intensity (125) =
Rainfall Intensity (15o) =
Rainfall Intensity (1100) =
8.0 acres
5.6 min.
0.62
7.693 in/hr
8.635 in/hr
9.861 in/hr
B-1
RATIONAL CALCULATIONS: PRE-DEVELOPMENT (LICK CREEK)
GENERAL INFORMATION RESULT
Description: Drainage area of site before proposed development.
Drainage Area (A1MPERv1ous) = 4.74 acres
Drainage Area (ALANDSCAPED) = 2.11 acres
Drainage Area (AuNDEVELOPED) = 6.02 acres Total Drainage Area (X2) =
TIME OF CONCENTRATION ff c)
GIVEN
Max. Travel Distance (DPRE) =
Velocity of Runoff (VPRE) =
**NOTE: Minimum Tc allowed = 10 min.
RUNOFF COEFFICIENTS
Runoff Coefficient (C1MPERv1ous) =
700 ft
ft 1.50 fsec
0.95
Runoff Coefficient (CLANoscAPED) = 0.30
Runoff Coefficient (CuNDEVELOPED) = 0.38
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient ( d) =
0.806
65
8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.785
Coefficient (b) = 76
Coefficient ( d) = 8.5
10 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) = 0.763
Coefficient (b) = 80
Coefficient ( d) = 8.5
25 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient ( e) = 0.754
Coefficient (b) = 89
Coefficient (d) = 8.5
50 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) =
Coefficient (b) =
Coefficient ( d) =
0.745
98
8.5
100 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.73
Coefficient (b) = 96
Coefficient ( d) = 8
000727-3376 Rational Calculations-Lick Creek
Tc(PREJ =
Wtd. Runoff Coefficient (Cwro) =
Rainfall Intensity (1 2) =
Rainfall Intensity (15) =
Rainfall Intensity (110) =
Rainfall Intensity (125) =
Rainfall Intensity (1 50) =
Rainfall Intensity (1100) =
12.9 acres
7.8 min.
0.58
7.693 in/hr
8.635 in/hr
9.861 in/hr
11 .148 in/hr
B-2
RATIONAL CALCULATIONS: POST-DEVELOPMENT (BEE CREEK)
GENERAL INFORMATION RESULT
Description: Drainage area of site after proposed development.
Drainage Area (AiM PERvious) = 5.57 acres
Drainage Area (ALANoscAPED) =
Drainage Area (AuNDEVELOPEo) =
TIME OF CONCENTRATION CTc)
GIVEN
Max. Travel Distance (DposT) =
Velocity of Runoff (VposT ) =
1.56 acres
0.90 acres
500 ft
ft 1.70 fsec
**NOTE: Minimum Tc allowed= 10 min.
RUNOFF COEFFICIENTS
Runoff Coefficient (C1MPERv1ous) = 0.95
Runoff Coefficient (C LANoscAPED) = 0.30
Runoff Coefficient (C uNoEVELOPED) = 0.38
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.806
65
8
5 YEAR FREQUENCY, RATE OF DISCHARGE (Q}
Coefficient (e) = 0.785
Coefficient (b) = 76
Coefficient (d) = 8.5
10 YEAR FREQUENCY. RATE OF DISCHARGE (Q}
Coefficient (e) = 0.763
Coefficient (b) = 80
Coefficient (d) = 8.5
25 YEAR FREQUENCY, RATE OF DISCHARGE (Q}
Coefficient (e) = 0.754
Coefficient (b) = 89
Coefficient (d) = 8.5
50 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.745
Coefficient (b) = 98
Coefficient (d) = 8.5
100 YEAR FREQUENCY, RATE OF DISCHARGE (Q}
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
000727-3376 Rational Calculations-Bee Creek
0.73
96
8
Total Drainage Area (P1) =
T C(POST) =
Wtd. Runoff Coefficient (C WTo)
Rainfall Intensity (12) =
Rainfall Intensity (15) =
Rainfall Intensity (1 10) =
Rainfall Intensity (125) =
Rainfall Intensity (150) =
Rainfall Intensity (1100) =
8.0 acres
4.9 min.
0.76
in/ 6.327 hr
in/ 7 .693 hr
in/ 8.635 hr
in/ 9.861 hr
in/ 11.148 hr
in/ 11 .639 hr
B-3
RATIONAL CALCULATIONS: POST-DEVELOPMENT (LICK CREEK)
GENERAL INFORMATION RESULT
Description: Drainage area of site after proposed development.
Drainage Area (AiMPERv1ous) = 5.29 acres
Drainage Area (ALANDSCAPED) =
Drainage Area (AuNDEVELOPED) =
TIME OF CONCENTRATION CTc)
GIVEN
Max. Travel Distance (Dposr ) =
Velocity of Runoff (Vposr) =
4.28 acres
3.28 acres
' 7 50 ft
ft 1.50 fsec
**NOTE: Minimum Tc allowed= 10 min.
RUNOFF COEFFICIENTS
Runoff Coefficient (C 1MPERv1ous) = 0.95
Runoff Coefficient (CLANoscAPEo) = 0.30
Runoff Coefficient (CuNDEVELOPEo) = 0.38
2 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0 .806
65
8
5 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
0.785
76
8.5
10 YEAR FREQUENCY. RATE OF DISCHARGE (Q)
Coefficient (e) = 0.763
Coefficient (b) = 80
Coefficient (d) = 8.5
25 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.754
Coefficient (b) = 89
Coefficient (d) = 8.5
50 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.745
Coefficient (b) = 98
Coefficient (d) = 8.5
100 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient (d) =
000727-3376 Rational Calculations-Lick Creek
0.73
96
8
Total Drainage Area (P2) =
Tc(POST) =
Wtd. Runoff Coefficient (C wro)
Rainfall Intensity (12) =
Rainfall Intensity (15) =
Rainfall Intensity (1 10) =
Rainfall Intensity (125) =
Rainfall Intensity (150) =
Rainfall lnte nsity (1100) =
12.9 acres
8.3 min.
0.59
in/ 6.327 hr
in/ 7.693 hr
in/ 8 .635 hr
in/ 9.861 hr
in/ 11 .1 48 hr
in/ 11 .639 hr
8-4
RUNOFF HYDROGRAPH (BEE CREEK)
2-YEAR HYDROGRAPH
10 ---------
0 10 I . --·--------·----------------. --·---\
LB Post-Develop1nent EJ Pre-Developn1enl
000727-3376 Rational Calculations-Be~ Creek
TIME
(min)
1--------~· --------
20 30
B-5
RUNOFF HYDROGRAPH (BEE CREEK)
5-YEAR HYDROGRAPH
25
~ Storage Vo
0 20 ~ ~ ,.-....
~ = ~ u '._,/
00 15
~
~
10
0 10
I CTI Post-Developn1ent cTI Pre-Developn1ent j
000727-3376 Rational Cakul ations-Bee Creek
TIME
(min)
20 30
B-5
RUNOFF HYDROGRAPH (BEE CREEK)
10-YEAR HYDROGRAPH
Storage Volum .
~ 25 -1--------/:
~ ~
< ~20-1------~········ ~ ~ U'-'
\fl
~
~ 15
10
0 J(£121.221
0 10
\Em Post--0~-v~l~p~e·n-t uJ P-r~-D~velop~11 ~nt
000727-3376 IL1tional Cakul.tlions-Fke Creek
-----!-------------
TIME
(min)
20 30
8-5
RUNOFF HYDROGRAPH (BEE CREEK)
25-YEAR HYDROGRAPH
35 --------
Storage Volutn
10
5
0
0 10
I Em P~-st-Development Eill P~;~D~l~~-~t I
000727-3376 Rational Cakulations-Bee Creek
TIME
(min)
20 30
B-5
RUNOFF HYDROGRAPH (BEE CREEK)
50-YEAR HYDROGRAPH
15-t----
5
0 10
J [ill P~~D~v~l~p~-e~t--EJ Pr~~-D~~l~p;rie~t \
000727-3376 R,1\ional Calculations-Bee Creek
TIME
(min)
------J-----------------------
20 30
B-5
RUNOFF HYDROGRAPH (BEE CREEK)
100-YEAR HYDROGRAPH
50
45
40
35
~
(.) 30
~ < -.. ~25 ~ ~ u .._,
if1
~ 20 ~
15
10
5
o~==
0 10
\ LTI Po ~t-D~ve lopment EJ Pre-Develop_~~~~-\
000727-3376 Rational Calculations-Bee Creek
TIME
(min)
---~------------·----------·
20 30
B-5
RUNOFF HYDROGRAPH (LICK CREEK)
2-YEAR HYDROGRAPH
5 ----
0~2LWWL222Lilllli2ZE1LLllliL.lil~
0 10
000727-3376 Rational Calculations-Lick Creek
TIME
(min)
20 30
B-6
RUNOFF HYDROGRAPH (LICK CREEK)
5-Y_EAR HYDROGRAPH
~ 15 v ~ < ,-...
~ ~ ~ u -..._;
fJ.J.
~ 10 ~
0 10
lcrn-r~~0e~~l ~pn1-e1~t -CJ_P_r~D~~e l o pn~ent j
000727-3376 Rational Calculations-Lick Cr~ek
TIME
(min)
20 30
B-6
RUNOFF HYDROGRAPH (LICK CREEK)
10-YEAR HYDROGRAPH
25
20 Storage Volum .
10
0 10
I Gill Post~D~v-~lopment miPre~D~velopment I
000727-3376 Rational Calcul ations-Lick Creek
TIME
(min)
20 30
B-6
RUNOFF HYDROGRAPH (LICK CREEK)
25-YEAR HYDROGRAPH
2s -Storage-V:olume_
0 10
[filiP-;;_De~lopment till Pre-Devclop~~\
000727-3376 Rational Calculations-Li.:k Creek
TIME
(min)
20 30
B-6
RUNOFF HYDROGRAPH (LICK CREEK)
SO-YEAR HYDROGRAPH
Storage Volu1ne
10
0 10
\till Post-Developtnen-t DJ Pre--Development I
000727-3376 Rational Calculations-Lick Creek
TIME
(min)
20 30
B-6
RUNOFF HYDROGRAPH (LICK CREEK)
100-YEAR HYDROGRAPH
Storage Volu1ne =
10
0 10
\ cll -l;o~t--Oe~l~p~~~~t-ITfilPr~~-D~~~i-~-pn~~~~t-\
000727-3376 Rational Calculations-Lick Creek
TIME
(min)
20 30
B-6
Project Description
Project File
Worksheet
Flow Element
Method
Solve For
Input Data
APPENDIX B -PILOT CHANNEL CALCULATIONS
Worksheet for Triangular Channel
i:\projects\700\3376-csmob-ii\dr report\3376t1 ra.fm2
Sub-Drainage Area A 1 -Pilot Channel
Triangular Channel
Manning's Formula
Channel Depth
Mannings Coefficient 0.013
Channel Slope
Left Side Slope
Right Side Slope
Discharge
Results
Depth
Flow Area
Wetted Perimeter
Top Width
Critical Depth
Critical Slope
Velocity
Velocity Head
Specific Energy
Froude Number
Flow is subcritical.
10/31/01
03:30:32 AM
0.30 %
3 H :V
3 H :V
2.50 cfs
0.57 ft
0.96 ft2
3.58 ft
3.39 ft
0.53 ft
0.004104 ft/ft
2.60 ft/s
0.11 ft
0.67 ft
0.86
Municipal Development Group
Haestad Methods. Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666
FlowMaster v5.07
Page 1 of 1
Project Description
Project File
Worksheet
Flow Element
Method
Solve For
Input Data
APPENDIX B -PILOT CHANNEL CALCULATIONS
Worksheet for Triangular Channel
i:\projects\700\3376-csmob-ii\dr report\3376t1 ra. fm2
Sub-Drainage Area 81 -Pilot Channel
Triangular Channel
Manning's Formula
Channel Depth
Mannings Coefficient 0.013
Channel Slope
Left Side Slope
Right Side Slope
Discharge
Results
Depth
Flow Area
Wetted Perimeter
Top Width
Critical Depth
Critical Slope
Velocity
Velocity Head
Specific Energy
Froude Number
Flow is subcritical.
10/31/01
03:31 :18 AM
0.20 %
3 H :V
3 H :V
6.70 cf s
0.88 ft
2.34 ft2
5.59 ft
5.30 ft
0.79 ft
0.003599 ft/ft
2.86 ft/s
0.13 ft
1.01 ft
0.76
Municipal Development Group
Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666
FlowMaster v5.07
Page 1 of 1
Project Description
Project File
Worksheet
Flow Element
Method
Solve For
Input Data
APPENDIX B -PILOT CHANNEL CALCULATIONS
Worksheet for Triangular Channel
i:\projects\700\3376-csmob-ii\dr report\3376t1 ra.fm2
Sub-Drainage Area C -Pilot Channel
Triangular Channel
Manning's Formula
Channel Depth
Mannings Coefficient 0.013
Channel Slope
Left Side Slope
Right Side Slope
Discharge
Results
Depth
Flow Area
Wetted Perimeter
Top Width
Critical Depth
Critical Slope
Velocity
Velocity Head
Specific Energy
Froude Number
Flow is subcritical.
10/31/01
03:31 :56 AM
0.20 %
3 H :V
3 H :V
6.80 cfs
0.89 ft
2.37 ft2
5.62 ft
5.33 ft
0.80 ft
0.003592 ft/ft
2.87 ft/s
0.13 ft
1.02 ft
0.76
Municipal Development Group
Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666
FlowMaster v5.07
Page 1 of 1
3376T1RA.out
winstorm TXDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 1
JOB CONTROL : 1
JOB SECTION : 727
JOB NUMBER : 3376
PROJECT DESCRIPTION : CS MED MOB II
DESIGN FREQUENCY : 10 Year
ANALYSYS FREQUENCY : 100 Year
MEASUREMENT UNITS: Input ENGLISH
Runoff computations
I.D.
A 1
D
c value Area
(acres)
0.900 1.070
TC
(min)
10.00
Mon Oct 29 16:51:12 2001
Output ENGLISH
Tc used
(min)
10.00
Intensity supply Q Total Q
(in/hr) (cfs) (cfs)
8.635 0.000 8. 315
winstorm TXDOT STORM DRAIN DESIGN Version 1.3 September 1997 PAGE 2
sag Inlet configuration Data
Inlet Inlet
I. D. Type
Len9th/ Grate Left slope Right slope
Per1m. Area Long Trans Long Trans
(ft) (sf) (%) (%) (%) (%)
Mon Oct 29 16:51:12 2001
Gutter Depth critical
n Depr. Allow Elev.
(ft) (ft)
A 1 CURB
D
5.000 n/a 1.92 2.00 0.53 2.00 0.015 0.240 0.750 No value
winstorm TXDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 3
sag Inlet Computation Data
Inlet Inlet I.D. Type
A 1 CURB
Len9th/ Grate Total Per1m. Area Q
(ft) (sf) (cfs)
5.000 n/a 8. 315
Inlet Total
Capacity Head
(cfs) (ft)
15.204 0.662
Mon Oct 29 16:51:12 2001
Ponded Widths Left Right
(ft) (ft)
13.150 12.950
Page 1
3376T1RA.out
D
winstorm TXDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 4
Mon Oct 29 16:51:12 2001
cumulative Junction Discharge computations
cumulative Node weighted
I.D. c-value
cumulative
Drainage Area
(acres)
Tc Intensity
Supplied
Discharge
(cfs)
Total
Discharge
(cfs) (min) Ci n/hr)
Al
0
winstorm
0.900 1.070 10.00
TxDOT STORM DRAIN DESIGN
conveyance configuration Data
Flowline Elev.
8.635 0.000 8. 315
Version 1.3 September 1997 PAGE 5
Mon Oct 29 16:51:12 2001
Run
I.D.
Node I.D.
US OS US OS shape # span
(ft)
Rise
(ft)
Length
(ft)
slope
(%)
n
1 Al 01 299.700 299.500 circ 1 n/a 1. 500 15.00 1.333 0.013
D
winstorm TXDOT STORM DRAIN DESIGN
conveyance Hydraulic computations
Run
Hydraulic Gradeline
us Elev os Elev slope
(%)
Depth
unif. Actual (ft) (ft)
1 303.394 303.300 0.63 0.912 1.500
version 1.3 September 1997 PAGE 6
Mon Oct 29 16:51:12 2001
velocity
unif. Actual Q (fps) (fps) (cfs) Cap (cfs)
June
LOSS (ft)
7.40 4.71 8.315 12.130 0.000
DISCHARGE FREQUENCY = 100 TAILWATER 304.00
Page 2
3376T1RA.out
0
winstorm TxDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 7
Runoff computations
I.D. c value Area
(acres)
Tc
(min)
TC Used
(min)
Mon Oct 29 16:51:12 2001
Intensity supply Q Total Q
(in/hr) (cfs) (cfs)
A 1 0.900 1.070 10.00 10.00 11. 639 0.000 11.209
0
winStorm TXDOT STORM DRAIN DESIGN Version 1.3 September 1997 PAGE 8
Mon Oct 29 16:51:12 2001
sag Inlet configuration Data
Inlet
I.D.
Inlet
Type
A 1 CURB
0
Winstorm
Len9th/ Grate Left
Per1m. Area Long
(ft) (sf) (%)
slope Right slope
Trans Long Trans
(%) (%) (%)
Gutter Depth Critical
n Depr. Allow Elev.
(ft) (ft)
5.000 n/a 1.92 2.00 0.53 2.00 0.015 0.240 0.750 No value
TXDOT STORM DRAIN DESIGN Version 1.3 September 1997 PAGE 9
Mon Oct 29 16:51:12 2001
sag Inlet Computation Data
Inlet Inlet
I. D. Type
A 1 CURB
0
winstorm
Len9th/ Grate
Peri m. Area
(ft) (sf)
5.000 n/a
Total
Q
(cfs)
11. 209
Inlet Total
Capacity Head
(cfs) (ft)
15.204 0.808
Ponded widths
Left Right
(ft) (ft)
14.700 14.450
TXDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 10
Mon Oct 29 16:51:12 2001
Page 3
cumulative Junction Discharge computations
Node
I.D.
Al
D
weighted
c-value
0.900
cumulative
Drainage Area
(acres)
1.070
cumulative
Tc
(min)
10.00
winstorm TXDOT STORM DRAIN DESIGN
conveyance configuration Data
Flowline Elev.
3376TlRA.out
Intensity
(in/hr)
11.639
Supplied
Discharge
(cfs)
0.000
Total
Discharge
(cfs)
11. 209
version 1.3 September 1997 PAGE 11
Mon Oct 29 16:51:12 2001
Run
I.D.
Node I.D.
US DS us DS Shape # span Rise Length slope n (ft) (ft) (ft) (%)
1 Al 01 299.700 299.500 circ 1 n/a 1. 500 15.00 1.333 0.013
D
winstorm TXDOT STORM DRAIN DESIGN
conveyance Hydraulic computations
Run
Hydraulic Gradeline
us Elev DS Elev slope
(%)
Depth
Unif. Actual
(ft) (ft)
1 304.171 304.000 1.14 1.139 1.500
D
winstorm TXDOT STORM DRAIN DESIGN
Computation Messages
version 1.3 September 1997 PAGE 12
Mon Oct 29 16:51:12 2001
velocity
uni f. Actual
(fps) (fps)
7.78 6.34
Q
(cfs)
Cap
(cfs)
June
Loss
(ft)
11.209 12.130 0.000
version 1.3 September 1997 PAGE 13
Mon Oct 29 16:51:12 2001
*Warning: Left pond ed width exceeds allowabl e widt h at inlet id Al . *Warning: Right ponded width exceeds allowable width at inlet id Al.
*Computation: Run = 1 -Pipe Flowing Full
*Warning: Left ponded width exceeds allowable width at inlet id Al.
Page 4
3376TlRA.out
*Warning : Right ponded width exceeds allowable width at inlet id Al.
*Computation: Run = 1 -Pipe Flowing Full
NORMAL completion of winstorm.
Page 5
3376T2RA.out
winstorm TXDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 1
JOB CONTROL : 1
JOB SECTION : 727
JOB NUMBER : 3376
PROJECT DESCRIPTION : CS MED MOB II
DESIGN FREQUENCY : 10 Year
ANALYSYS FREQUENCY : 100 Year
MEASUREMENT UNITS: Input ENGLISH
Runoff computations
I.D.
c 1 c 2
D
c value Area
(acres)
0.900
0.950
1.960
0.920
Tc
(min)
10.00
10.00
Mon Oct 29 16:51:47 2001
Output ENGLISH
Tc used
(min)
10.00
10.00
Intensity supply Q Total Q
(in/hr) (cfs) (cfs)
8.635
8.635
0.000
0.000
15. 231
7.547
winstorm TxDOT STORM DRAIN DESIGN Version 1.3 September 1997 PAGE 2
sag Inlet configuration Data
Inlet
I.D.
Inlet
Type
Len~th/ Grate Left
Per1m. Area Long
(ft) (sf) (%)
slope Right slope
Trans Long Trans
(%) (%) (%)
Mon Oct 29 16:51:47 2001
Gutter Depth Critical
n Depr. Allow Elev.
(ft) (ft)
C 1 CURB
D
8.000 n/a 0.50 2.00 0.53 2.00 0.015 0.240 0.750 No value
winstorm TxDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 3
Sag Inlet Computation Data
Inlet Inlet Len~th/ Grate Total
I.D. Type Per1m. Area Q
(ft) (sf) (cfs)
Inlet Total
capacity Head
(cfs) (ft)
Mon Oct 29 16:51:47 2001
Ponded widths
Left Right
(ft) (ft)
Page 1
C 1 CURB 8.000 n/a 15. 231
3376T2RA. out
24.326 0.725 11.650 19.250
0
winstorm TxDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 4
Mon Oct 29 16:51:47 2001
cumulative Junction Discharge computations
cumulative Node weighted cumulative
I.D. c -value Drainage Area (acres) Tc Intensity
supplied
Discharge (cfs)
Total
Discharge
(cfs) (min) (in/hr)
Cl 0.916 2.880 11. 20 8. 229 0.000 21. 709
Jl 0.950 0.920 10.00 8.635 0.000 7.547
C2 0.950 0.920 10.00 8.635 0.000 7.547
J2 0.950 0.920 10.00 8.635 0.000 7.547
0
winstorm TX DOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 5
Mon Oct 29 16:51:47 2001
Conveyance configuration Data
Flowline Elev. Run
I.D.
Node I. D.
US DS US DS Shape# Span Rise Length slope n
1 Cl 01 299.350 299.000 Ci re
2 Jl Cl 301. 950 300.350 Ci re
3 J2 Jl 302.500 301. 950 circ
4 C2 J2 303.100 302.500 circ
0
winStorm TX DOT STORM DRAIN DESIGN
conveyance Hydraulic Computations
Run
Hydraulic Gradeline
us Elev DS Elev slope
(%)
Depth
unif. Actual (ft) (ft)
1 303.760 303.300 0.92 1.875 2.000
(ft) (ft). (ft) (%)
1 n/a 2.000 50.00 0.700 0.013
1 n/a 1. 500 240.00 0.667 0.013
1 n/a 1. 500 80.00 0.688 0.013
1 n/a 1. 500 80.00 0.750 0.013
version 1.3 September 1997 PAGE 6
Mon Oct 29 16:51:47 2001
velocity
unif. Actual (fps) (fps)
Q
(cfs) Cap (cfs)
June
LOSS
(ft)
7.10 6.91 21.709 18.927 0.000
Page 2
D
2
3
4
304.995
305.405
305.818
303.760
304.995
305.405
0.52
0. 52
0.52
1.092
1.078
1.042
DISCHARGE FREQUENCY = 100
1. 500
1. 500
1. 500
3376T2RA.out
5.47 4.27 7.547
5.55 4.27 7.547
5.75 4.27 7.547
TAILWATER = 304.00
8. 577
8. 710
9.097
0.000
0.000
0.000
winStorm TXDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 7
Runoff computations
I.D.
c 1 c 2
n
c value Area
(acres)
0.900
0.950
1.960
0.920
TC
(min)
10.00
10.00
Winstorm TxDOT STORM DRAIN DESIGN
sag Inlet configuration Data
Tc used
(min)
10.00
10.00
Mon Oct 29 16:51:47 2001
Intensity Supply Q Total Q
Ci n/hr) (cfs) (cfs)
11.639
11. 639
0.000
0.000
20.532
10.173
version 1.3 September 1997 PAGE 8
Mon Oct 29 16:51:47 2001
Inlet
I.D.
Inlet
Type
Length/ Grate Left
Per1m. Area Long
(ft) (sf) (%)
slope Right slope
Trans Long Trans
(%) (%) (%)
Gutter Depth
n Depr. Allow
(ft) (ft)
critical
Elev.
C 1 CURB
0
8.000 n/a 0.50 2.00 0.53 2.00 0.015 0.240 0.750 No value
winstorm TxDOT STORM DRAIN DESIGN
Sag Inlet computation Data
Inlet Inlet Length/ Grate Total
Version 1.3 September 1997 PAGE 9
Mon Oct 29 16:51:47 2001
Inlet Total Ponded widths
Page 3
3376T2RA.out
I. D. Type Perim. Area
(ft) (sf)
Q
(cfs)
capacity Head Left Right
(cfs) (ft) (ft) (ft)
C 1 CURB 8.000 n/a 20.532 24.326 0.884 13.000 21.550
0
winstorm TxDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 10
Cumulative Junction Discharge Computations
Node weighted
I.D. c-value
Cl 0.916
Jl 0.950
C2 0.950
J2 0.950
0
cumulative
Drainage Area (acres)
2.880
0.920
0.920
0.920
cumulative
Tc Intensity
(min) Ci n/hr)
11.13 11.134
10.00 11.639
10.00 11.639
10.00 11.639
Mon Oct 29 16:51:47 2001
supplied
Discharge
(cfs)
0.000
0.000
0.000
0 .000
Total
Discharge
(cfs)
29. 372
10.173
10.173
10.173
winstorm TX DOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 11
conveyance configuration Data
Run
I.D.
1
2
3 4
0
Node I. D.
US DS
Cl 01
Jl Cl
J2 Jl C2 J2
winstorm TX DOT
Flowline Elev.
US OS
299.350 299.000
301. 950 300.350
302.500 301.950
303.100 302.500
STORM DRAIN DESIGN
conveyance Hydraulic Computations
shape # Span
(ft)
Ci re 1 n/a
Circ 1 n/a
Circ 1 n/a circ 1 n/a
Mon Oct 29 16:51:47 2001
Rise
(ft)
2.000
1. 500
1. 500
1. 500
Length
(ft)
slope
(%)
n
50.00 0.700 0.013
240.00 0.667 0.013
80 .00 0.688 0.013
80.00 0.750 0.013
Version 1.3 September 1997 PAGE 12
Mon Oct 29 16:51:47 2001
Hydraulic Gradeline Depth velocity June
LOSS Run us Elev os Elev slope Unif. Actual unif. Actual Q Cap
Page 4
3376T2RA.out
(%) (ft) (ft) (fps) (fps) (cfs) (cfs) (ft)
------------------------------------------------------------------------------
1 304.843 304.000 1. 69 1. 875 2.000 9.60 9.35 29. 372 18 . 927 0.000
2 307.094 304.843 0.94 1. 407 1. 500 5. 91 5.76 10.173 8. 577 0.000
3 307.844 307.094 0.94 1.407 1. 500 5.91 5.76 10.173 8. 710 0.000
4 308.595 307.844 0.94 1.407 1. 500 5.91 5.76 10.173 9.097 0.000
0
winstorm TXDOT STORM DRAIN DESIGN version 1.3 September 1997 PAGE 13
Mon Oct 29 16:51:47 2001
computation Messages
*Warning: Right ponded width exceeds allowable width at inlet id Cl.
*Warning : Discharge decreased downstream Junction J2 -previous intensity used
*Warning: Discharge decreased downstream Junction Jl -previous intensity used
*Computation: Run 1 -Insufficient capacity *Computation: Run = 2 -Pipe Flowing Full
*Computation: Run = 3 -Pipe Flowing Full
*Computation: Run = 4 -Pipe Flowing Full
*Warning: Left ponded width exceeds allowable width at inlet id Cl.
*Warning: Right ponded width exceeds allowable width at inlet id Cl.
*Warning: Discharge decreased downstream Junction J2 -previous intensity used
*Warning: Discharge decreased downstream Junction Jl -previous intensity used
*Computation: Run 1 -Insufficient capacity
*Computation: Run 2 -Insufficient Capacity
*Computation: Run 3 -Insufficient Capacity
*Computation: Run 4 -Insufficient capacity
NORMAL completion of Winstorm.
Page 5
RATIONAL CALCULATIONS -(Sub Drainage Areas)
GENERAL INFORMATION
Description: Sub-Drainage Area D1
Drainage Area =
Coefficient of Runoff (Cwr0 ) =
TIME OF CONCENTRATION (Tc)
GIVEN
Maximum Travel Distance (D1) =
Velocity of Runoff (VcREEK) =
Maximum Travel Distance (D2) =
Velocity of Runoff (VcHANNELl =
Maximum Travel Distance (D3) =
Velocity of Runoff (V3) =
0.68 acres
0.60
0 ft
ft 3.50 fsec
0 ft
2.25 ft/sec
450 ft
1.00 ft/sec
**NOTE: Minimum Tc allowed= 10 min.
2 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.806
Coefficient (b) = 65
Coefficient ( d) = 8
5 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) = 0.785
Coefficient (b) = 76
Coefficient ( d) = 8.5
10 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.763
Coefficient (b) = 80
Coefficient ( d) = 8.5
25 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient ( e) = 0.754
Coefficient (b) = 89
Coefficient ( d) = 8.5
50 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) = 0.745
Coefficient (b) = 98
Coefficient ( d) = 8.5
100 YEAR FREQUENCY, RATE OF DISCHARGE (Q)
Coefficient (e) =
Coefficient (b) =
Coefficient ( d) =
000727-33 76 Rati onal Calculations-Sub-Areas
0.73
96
8
RESULT
Tc1 =
Tc2 =
Tc3 =
Tc=
Rainfall Intensity (1 2) =
Rainfall Intensity (15) =
Rainfall Intensity (110) =
Rainfall Intensity (1 25) =
Rainfall Intensity (1 50) =
Rainfall Intensity {1 100) =
0.0 min.
0.0 min.
7.5 min.
7.5 min.
6.327 inlr.r
7.693 in/~"
8.635 in/hr
9.861 in/hr
11.148 in/hr
11.639 in/hr
B-8
Texas Hydraulic System Culvert Design
CS MED MOBii
000727-3376
Brazos County
On-Site Storm Sewer Improvements
Dl
Shape: !circular
Material: I Concrete
S~an:~ft
Rise: CIQ2J ft
Barrels: I 11
Discharge Description
lOYR
100 YR
Q
total
(cfs)
3.55
4.79
*Backwater (BW = HW -TW -S·L)
HW TW
elevation elevation
(ft) (ft)
304.06 303.50
304.11 303.50
I :\PROJECTS\700\33 76-C-l \DRREP0-1 \3376Tl RA.CL V
Length(L): I 50.ool ft
Slope(S): I o.01otj
n:~
Ke:~
Entrance Type:l ._M_i_te_r_ed ______ ~
BW*
(ft)
0.06
0.11
v
out
(ft)
3.47
3.61
Q Inlet Ctl Outlet Ctl
over road HW depth HW depth
(cfs) (ft) (ft)
0.82 1.21 1.56
1.95 1.26 1.61
I 0/29/0 I