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Home My WebLink About47 MM University Heights Condos 99-323 1200 WelshGALINDO ENGINEERS AND PLANNERS, INC. 3833 South Texas Ave., Suite 213 Bryan, Texas 77802 {409) 846-8868 Mr. Jeffrey Tondre, P.E. Assistant City Engineer City of College Station College Station , TX Subject: Drainage Study November 22 , 1999 University Heights Condominiums College Station , TX Dear Jeff: Pleased find enclosed the referenced report for your review. This reports covers the 1.3978-acre tract to be occupied by the proposed University Heights Condominiums. Sincerely , GALINDO ENGINEERS AND PLANNERS, INC. Christian A. Galindo, P.E., R.P.L.S. President cc : Horizon Homes GALINDO ENGINEERS AND PLANNERS, INC. 3833 South Texas Ave., Suite 213 Bryan, Texas 77802 (409) 846-8868 UNIVERSITY HEIGHTS CONDOMINIUMS DRAINAGE REPORT 1. TRACT DESCRIPTION The University Heights Condominiums project covers a 1.3978 -acre tract located on the northwest corner of Welch and Nevada Streets. A separate 24 "x36" sheet, Site Plan & Drainage Plan , is part of this report and will be referred here as Exhibit 1. The adopted Flood Insurance Study does not identify the existence of a 100-flood plain affecting this tract (Map # 48041 C 0143 C, July 2 , 1992). 2. STORMWATER RUNOFF All of the runoff from the 1.3978 acres flows in a general southeast direction , as sheet flow , onto Nevada Street. The current site is currently vacant. Exhibit 1 shows the tract, its location and its topography . Topographic data was obtained from city of College Station records . The tract has been defined as one drainage section . Exhibit 2 shows the runoff calculations for 5 , 10, 25 , 50 and 100-year rainfalls for each of the two sections . Runoff detention computations have been made using the 100-year return period and therefore the maximum allowed runoff after development is 6.51 cfs . In order to mitigate the effect of the increase runoff, a location for a detention facility was defined on the project parking lot. 3. INFLOW HYDROGRAPHS -POND 1 Haestad Methods Quick Tr-55 V. 5.47 was used for the analysis given in Exhibit 3 (in 3 pages). This Exh ibit graphically shows individual hydrographs for all storm frequencies . The estimated required storage for the 100-yr storm is calculated at 0.096 ac -ft . 4. DETENTION FACILITY -POND 1 This pond will be built on the project 's parking lot. The weir will consist of a 3.0' long curb cut on the south end of the parking lot. The curb at this location will be 0 .7' (8.5 " curb) high . The flow elevation is set at 312 .9 ' and the curb elevation is set at 292 .5 '. This weir will empty onto a 4 '-wide concrete flume with an upper flow elevation of 312 .8'. This flow will in turn discharge onto Nevada street at the approximate gutter elevation of 311 .5 '. Exhibit 4 shows the storage volume calculations based on the proposed grading of the parking lot. The available storage is calculated at 0.13 ac-ft. Exhibit 5 estimates that the available storage at a maximum allowed peak outflow of 6.51 cfs the storage required will be about 0 .1 ac -ft . Thus the available storage is sufficient to pond the excess runoff. - 1 - Haestad Methods Pondpack V. 5.21 was used in the ponding calculations . Exhibit 6 shows the input data for the proposed Vertical-Rectangular weir (curb cut). Exhibit 7 (8 pages) shows the routing calculations for a multiple storm . Peak outflows for each frequency do not exceed pre- development conditions . The following is the routing summary in terms of maximum outflow allowed (pre-development conditions) and peak attained : Storm Max. Allowed Peak Attained Max. Elevation 5-year 4.30 3.63 313.45 10-year 4.83 3.99 313.49 25-year 5.51 4.43 313.53 50-year 6.23 4.89 313 .57 100-year 6.51 5 .07 313.59 Exhibit 8 shows the calculations associated with the 4.0'-wide flume that drains this pond over the surface onto Nevada St. For a Q-100 = 5.07 cfs the depth of the proposed triangular flume needs to be approximately 5" and the resulting discharge velocity is calculated at 7 .78 fps . Finally , the Q-10 flow onto Nevada St. is estimated to rise to 0.23 ', or approximately one half of the west bound lanes, that is approximately 6.5 '. This leaves a net 7.5 ' x 2 = 15.0 ' of c lear road dur ing a 100'-yr rain. Exhibit 9. The above referenced Exhibit 1 shows the location of the pond and depicts the construction details necessary for implementation of this project. 5. CERTIFICATION Th is report and design conform with the City of College Station Drainage Policy and Design Standards. - 2 - ~''''"'\'''' $';t. OF r~ ''lt .= "'~ ................. ,..r.., ''1. : c, .. ·· * ·· .. U" ~,. -* •' . ~ i.. ""' .. •• 7' ·~ 4*:" ·~*a. .;fl.!-·······································~ ~CHRISTIAN A. GALINDOI ~ .............................................. .iJ! ~ . " ~~\ 53425 /Q:-~ ~ 'I>_ ... -1> ... ~ ••• 4.i ""' ~ 0;t' ···.{G1s1t~:::-·· ~4.i :E ~,, e'ss ............ ~\j .: ~. IONAL t.. ~-~'\ ........ ' "-'~ ':t..''''~ CHRISTIAN A. GALINDO, P.E . # 53425, R.P.L.S. # 4473 November 22 , 1999 Job: 42-99 Date : 11 /18/99 RUNOFF CALCULATIONS-RATIONAL METHOD UNIVERSITY HEIGHTS CONDOMINIUMS COLLEGE STATION , TX (County : Brazos) Tc = 10.0 when calc. value < 10.0 ====== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== Section Soil Type A Acres c Ve loc. fps Length ft T cone . in min . Ca le . Used 5 yrs 10 yrs 25 y rs 50yrs 100yrs Q 5yrs Q 10 yrs Q 25 yrs Q 50y rs Q 100yrs ====== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== ===== Pre-development Conditions Grass 1.398 0.400 2 .000 550 4 .6 10.0 7 .693 8 .635 9 .861 11 .148 11 .639 4 .30 4 .83 5 .51 6 .23 6 .51 Maximum Development HOR 1.398 0 .800 7.000 580 1.4 10.0 7 .693 8 .635 9 .861 11.148 11 .639 8 .60 9 .66 11 .03 12.47 13.02 County : Brazos Constants for use in formula : l =b /(t+d ) "'e 2-yr 5-yr 10 -yr 25-yr 50-yr 100-yr b 65 .000 76 .000 80 .000 89 .000 98.000 96 .000 e 0 .806 0 .785 0 .763 0.754 0 .745 0 .730 d 8 .000 8 .500 8.500 8 .500 8 .500 8 .000 w ~ CX> ~ w w ~ C/J 0 c: \j -=r 0 n;t >< ~ Q) "' )> < (!) ~ C/J c: ~ ;::;: (!) I\) ..... ~ w DJ V) ... ~ '< Q) :::J n;t >< Q) ~ "' ~ ~ CX> 0 I\) -~ .i:. 0 ~ co -CX> .i:. ~ m • CX> CX> ~ m CX> m ~ >< ~ -m ~ N Quick TR-55 Ver.5.47 S/N: Executed: 11:47:06 11-22-1999 5 yr F L 0 w c f MODIFIED RATIONAL METHOD UNIVERSITY HEIGHTS CONDOMINIUMS ********************************************************************** * * RETURN FREQUENCY: 5 yr 'C' Adjustment: 1.000 Allowable Outflow: Required Storage: 4.30 cfs 0.063 ac-ft * * *--------------------------------------------------------------------* * Peak Inflow: 7.72 cfs Inflow .HYD stored: SIN .HYD * I Td = 13 minutes I Return Freq: /-------Approx. Duration for Max. Storage ------/ C adj.factor: 1.00 1 I I x . I. Tc= I Q 10.00 7.693 8.60 minutes in/hr cf s I I I I I I Required Storage I 0.063 ac-ft I I x x x x x x x ix x x x x x x x x x x I Area (ac): Weighted C: Adjusted C: 1. 40 0.80 0.80 Td= 13 minutes I 6.903 in/hr Q 7.72 cfs x EXHIBIT 3 s o o o o o o o o o o o o o o o o Q= 4.30 cfs 10 yr F L 0 w c f s x o I. Ix (Allow.Outflow) o I I x o I NOT TO SCALE I x o I ============ I o I I x -----------------------1-----------------------------1------------ 15.00 minutes 17.43 minutes ********************************************************************** * * RETURN FREQUENCY: 10 yr 'C ' Adjustment: 1.000 Allowable Outflow: Required Storage: 4.83 cfs 0.071 ac-ft * * *--------------------------------------------------------------------* * Peak Inflow: 8.69 cfs Inflow .HYD stored: lOI N .HYD * I Td = 13 minutes I Return Freq: /-------Approx. Duration for Max. Storage ------/ C adj.factor: 1.00 1 I x x . I. Tc= I Q 10. 00 8.635 9.66 minutes in/hr cfs I I I I I I Required Storage I 0.071 ac-ft I I I Area (ac) : Weighted C: Adjusted C: Td= I 1. 4 0 0.80 0.80 xx x xx x xJx xx xx xx x xx x Q 13 minutes 7.770 in/hr 8.69 cfs I x o o o o o o o o o o o o o o o o Q= 4.83 cfs o I. Ix (Allow.Outflow) o I I x o I NOT TO SCALE I x o I ============ I I o I I x ------------------------1-----------------------------1------------ 15.00 minutes 17.44 minutes F L 0 w c f s I ********************************************************************** * * RETURN FREQUENCY: 25 yr 'C' Adjustment: 1.000 Allowable Outflow: Required Storage: 5.51 cfs 0.081 ac-ft * * *--------------------------------------------------------------------* * Peak Inflow: 9.94 cfs Inflow .HYD stored: 25IN .HYD * Td = 13 minutes I Return Freq: 25 yr /-------Approx. Duration for Max. Storage------/ C adj.factor: 1.00 1 I I I I I I x . I. Tc= I Q 10.00 9.861 11. 03 minutes in/hr cfs I I I I I I Area (ac): Weighted C: Adjusted C: Required Storage I 0.081 ac-ft I Td= I I 1. 40 0.80 0 :90 x x x x x x xix x x x x x x x x x x Q 13 minutes 8.885 in/hr 9.94 cfs I x o o o o o o o o o o o o o o o o Q= 5.51 cfs x o I. Ix (Allow.Outflow) o I I x o I NOT TO SCALE I x o I ============ I o I I x -----------------------1-----------------------------1------------ 15.00 minutes 17.45 minutes ********************************************************************** * * RETURN FREQUENC Y: 50 yr 'C' Adjustment: 1.000 Allowa ble Outflow: Required Storage: 6.23 cfs 0.092 ac-ft * * *--------------------------------------------------------------------* * Peak Inflow: 11.25 cfs Inflow .HYD stored: 50IN .HYD * I Td = 13 minutes I Return Freq: 50 yr /-------Approx. Duration for Max . Storage------/ C adj.factor: 1.00 I I I Tc= 10.00 minutes I I I 11.148 in/hr I Area (ac): 1.40 I Q 12.47 cfs I Weighted C: 0.80 I .1. I Adjusted C: 0.80 F I I L I Required Storage I 0 I 0.092 ac-ft I Td= 13 minutes w I I I 10.056 in/hr I x x x x x x xix x x x x x x x x x x Q 11.25 cfs c I I f I x x s I o o o o o o o o o o o o o o o o Q= 6.23 cfs I x o I. Ix (Allow.Outflow) I o I I I x o I NOT TO SCA LE I x I o I ============ I I o I I x '-----------------------1-----------------------------1------------ 15.00 minutes 17 .46 minutes ********************************************************************** * * RETURN FREQUENCY: 100 yr 'C ' Adjustment: 1.000 Allowable Outflow: Required Storage: 6.51 cfs 0.096 ac-ft * * *--------------------------------------------------------------------* * Peak Inflow: 11.74 cfs Inflow .HYO stored: lOOIN .HYO * I Td = 13 minutes I Return Freq: 100 yr /-------Approx. Duration for Max . Storage ------/ C adj.factor: 1.00 I I I Tc= 10.00 minutes I I I 11.639 in/hr I Area (ac): 1.40 I Q 13.02 cfs I Weighted C: 0.80 I . I. I Adjusted C: 0.80 F I I L I Required Storage I 0 I 0.096 ac-ft I Td= 13 minutes W I I I 10.495 in/hr I xx xx xx xix xx xx xx xx xx Q 11 .74 cfs c I I f I x x s I o o o o o o o o o o o o o o o o Q= 6.51 cf s I x o I. Ix (Allow.Outflow) I o I I I x o I NOT TO SCALE I x I o I ============ I I o I I x '-----------------------1-----------------------------1------------ 15 .00 minutes 17.45 minutes ************************************************************************ ************************************************************************ * * * * * MODIFIED RATIONAL METHOD ----Grand Summary For All Storm Frequencies * * * * * First peak .outflow point assumed to occur at Tc hydrograph recession leg. UNIVERSITY HEIGHTS CONDOMINIUMS Area = 1.40 acres Tc = 10 .00 minutes ............................................................................ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . VOLUMES Frequency Adjuste d Duration Intens. Qpeak Allowable I Inflow Storage (years) 'C' minutes in/hr cfs cfs I (ac-ft) (ac-ft) ------------------------------------------------------1--------------------- 5 0 .800 13 6.903 7.72 4 .30 I 0.138 0 .063 10 0.800 13 7 .770 8.69 4.83 I 0.156 0.071 25 0 .800 13 8.885 9.94 5.51 I 0.178 0.081 50 0.800 13 10.056 11.25 6.23 I 0.201 0.092 100 0.800 13 10.495 11.7 4 6.5 1 I 0.210 0 .096 POND-2 Version: 5.21 S/N: EXHIBIT 4 UNIVERSITY HEIGHTS CONDOMINIUMS CALCULATED 11-22-1999 12:07:24 DISK FILE: C:\lA\42-99\42-99 .VOL Planimeter scale: 1 inch = 1 ft. * Elevation (ft) Planimeter (sq. in.) Area (acres) Al+A2+sqr(Al*A2) (acres) Volume (acre-ft) Volume Sum (acre-ft) 312.90 313.25 313.50 313.60 250.00 7,700.00 15,300.00 17,300.00 0.01 0.18 0.35 0.40 0.00 0.21 0.78 1.12 0.00 0.03 0.06 0.04 0.00 0.03 0.09 0.13 * Incremental volume computed by the Conic Method for Reservoir Volumes. Volume= (1/3) * (EL2-EL1) * (Areal+ Area2 +sq.rt. (Areal*Area2)) where: ELl, EL2 Areal,Area2 Volume = Lower and upper elevations of the increment = Areas computed for ELl, EL2, respectively = Incremental volume between ELl and EL2 PON0-2 Ve rs ion : 5.21 S /N : >>>>> OUT FLOW HYOROG RAPH ESTI MAT OR <<<<< Inf low Hydr o graph: C :\lA \42 -99\lO OI N .HYO Qpeak = 11.7 cfs Estima ted Outflow: C:\lA\42-9 9\ES TI MA TE.EST Qpeak = 6.5 cfs Appr o ximate Storage Vo lume (computed from t = 0.00 t o 0.29 hrs) 0.1 acre-ft EXHIBIT 5 PON0 -2 Version: 5.21 S/N: Plott ed: 1 1 -18-1999 .02 .0 3 .05 .07 .0 8 .1 .1 2 .1 3 .15 .17 .18 . 2 .22 .23 .25 .27 .28 .3 . 3 2 .33 .35 .37 * x Flow (cfs) 0 .0 1 .5 3.0 4.5 6.0 7.5 9.0 10 .5 12.0 13.5 15.0 16.5 .------1-----1-----1-----1-----1-----1-----1-----1-----1-----1-----1- 1 -I x I x -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I I -I x x x * x * * x x x * I * TIM E (h r s ) * x x * x x * x x * x x * x * * x x x x x * * x x * x * x * x x * x * * * x x x * * F ile: C :\lA\42-99 \l OOIN .HYO F il e: C:\lA\42-99\ESTIMATE.EST * * * * * * Qmax Qmax * * * * * * * * * * * * * * * 1 1.7 c fs 6.5 c fs Outlet Structure File: 42-99 .STR POND-2 Version: 5.21 Date Executed: S/N:. Time Execµted: ******************************* UNIVERSITY HEIGHTS CONDOMINIUMS ***** COMPOSITE OUTFLOW SUMMARY **** Elevation (ft) Q (cfs) Contribut ing Structures 312.90 313 .10 313.30 313.50 313. 60 0.0 0.8 2.3 4.1 5.2 1 1 1 1 1 Outlet Structure File: C:\lA\42-9 9 \42-99 .STR Planimeter Input File: C:\lA\42-99\42-99 .VOL Rating Table Output File: C:\lA\42-99\42-99 .PND Min. Elev. (ft) = 312.9 Max. Elev. (ft) = 313.6 Iner. (ft) SYSTEM CONNECTIVITY ********************************************** Structure No. Q Table Q Table WEIR-VR 1 -> 1 Outflow rating table summary was stored in file: C:\lA\42-99\42-99 .PND >>>>>> Structure No. 1 <<<<<< (Input Data) WEIR-VR Weir -Vertical Rectangular El elev. (ft)? E2 elev. (ft)? Weir coefficient? Weir elev. (ft)? Length (ft)? Contracted/Suppressed 312.9 313.601 3 .087 3 12.9 3 .0 0 (C/S)? C Outflow Rating Table for Structure #1 WEIR-VR Weir -Vertical Rectangular ***** INLET CONTROL ASSUMED ***** Elevation (ft) Q (cfs) Computation Messages --------------------------------------------- 312.90 0.0 H =0.0 313.10 0.8 H =. 2 313 . 30 2.3 H =. 4 313. 50 4. 1 H =.6 313. 60 5.2 H =.7 C = 3.087 L (ft) = 3 H (ft) Table elev. -Invert ele v . ( 31 2 . 9 ft ) Q (cfs) = C * (L-.2H) * (H**l.5) --Co ntracted Weir EXHIBIT 6 . 2 POND-2 Version: 5 .21 S/N: .: ,.···Page 1 EXECUTED: 11-22-1999 11:46:08 STORM # 1 Return Freq: 5 years ************************************* * UNIVERSITY HEIGHTS CONDOMINIUMS * ****************** SUMMARY OF ROUTING COMPUTATIONS ****************** Pond File: C:\lA\42-99\42-99 .PND Inflow Hydrograph: C:\1A\42-99\5IN .HYO Outflow Hydrograph: C:\lA\42-99\5 OUT .HYO Starting Pond W. S.' Elevation = 312.90 ft ***** Summary of Peak Outflow and Peak Elevation Peak Inf low Peak Outfl o w Peak Elevation 7.72 cfs 3.63 cfs 313.45 ft ***** Summary of Approximate Peak Storage ***** Initial Storage Peak Storage From Storm Total Storage in Pond 0.00 ac-ft 0.08 ac-ft 0.08 ac-ft ***** EXHIBIT 7 EXECUTED: 11-22-1999 11:46:08 STORM # 2 Return Freq: 10 years ************************************* * UNIVERSITY HEIGHTS CONDOMINIUMS * ****************** SUMMARY OF ROUTING COMPUTATIONS ****************** Pond File: C:\lA\42-99\42-99 .PND Inflow Hydrograph: C:\lA\42-99\lOIN .HYO Outflow Hydrograph: C:\lA\42-99\10 OUT .HYO Starting Pond W.S. Elevation = 312.90 ft ***** Summary of Peak Outflow and Peak Elevation Peak Inflow Peak Outflow Peak Elevation 8.69 cfs 3.99 cfs 313.49 ft ***** Summary of Approximate Peak Storage ***** Initial Storage Peak Storage From Storm Total Storage in Pond 0.00 ac-ft 0.09 ac-ft 0.09 ac-ft ***** POND-2 Version: 5.21 S/N: EXECUTED: 11-22-1999 11:46:08 STORM # 3 Page 2 Return Freq:· 25 years ************************************* * UNIVERSITY HEIGHTS CONDOMINIUMS * ****************** SUMMARY OF ROUTING COMPUTATIONS ****************** Pond File: C:\lA\42-99\42-99 .PND Inflow Hydrograph: C:\1A\42-99\25IN .HYO Outflow Hydrograph: C:\lA\42-99\25 OUT .H YO Starting Pond W.S. Elevation = 312.90 ft ***** Summary of Peak Outflow and Peak Elevation ***** Peak Inf low Peak Outflow Peak Elevation 9.94 cfs 4.43 cfs 313.53 ft ***** Summary of Approximate Peak Storage ***** Initial Storage Peak Storage From Storm Total Storage in Pond 0 .00 ac-ft 0.10 ac-ft 0 .10 ac-ft EXECUTED: 11-22-1999 11:46:08 STORM # 4 Retur n Freq: 50 years ************************************* * UNIVERSITY HEIGHTS CONDOMINIUMS * ****************** SUMMARY OF ROUTING COMPUTATIONS ****************** Pond File: C:\lA\42-99\42-99 .PND Inflow Hydrograph: C:\1A\42-99\50IN .HYO Outflow Hydrograph: C:\lA\4 2 -99\50 OUT .HYO Starting Pond W.S. Elevation = 312.90 ft ***** Summary of Peak Outflow and Peak Elevation Peak Inflow Peak Outflow Peak Elevation 11.25 cfs 4 .89 cfs 313.57 ft ***** Summary of Approximate Peak Storage ***** Initial Storage Peak Storage From Storm Total Storage in Pond 0.00 ac-ft 0 .1 2 ac-ft 0.12 ac-ft ***** POND-2 Version: 5.21 S/N: EXECUTED: 11-22-1999 11:46:08 STORM # 5 Page 3 Return Freq: 100 years ************************************* * UNIVERSITY HEIGHTS CONDOMINIUMS * ****************** SUMMARY OF ROUTING COMPUTATIONS ****************** Pond File: C:\lA\42-99\42-99 .PND Inflow Hydrograph: C:\lA\42-99\lOOIN .HYO Outflow Hydrograph: C:\lA\42-99\100 OUT .HYO Starting Pond W.S. Elevation = 312.90 ft ***** Summary of Peak Outflow and Peak Elevation Peak Inflow Peak Outflow Peak Elevation 11.74 cfs 5.07 cfs 313.59 ft ***** Summary of Approximate Peak Storage ***** Initial Storage Peak Storage From Storm Total Storage in Pond 0.00 ac-ft 0.12 ac-ft 0.12 ac-ft ***** POND-2 Version : 5.21 S/N : Page 4 EXECUTED: 11-22-1999 11: 4 6: 08 STORM # 1 Return Freq: 5 year:s Flow (cfs) 0.0 1.0 2 .0 3.0 4.0 5.0 6 .0 7.0 8.0 9.0 10.0 11. 0 ------1-----1-----1-----1-----1-----1-----1-----1-----1-----1-----1- .0 5 x * x * .07 x * x * .09 x * x * .1 x * x * .12 x * x * .14 x * x * .15 x * x * .17 x * I x * .19 -I x * I x * . 2 -I x * I x * .22 -I x * I x * .24 -I x * I x * .26 -1 x * I x * .27 -J x * I x * .29 -I x * I x * .31 -I * I * x .32 -I * x I * x .34 -I * x I * x .36 -I * x I * x I TIME (hrs) x File: C:\lA\42-99\5 OUT .HYO Qmax 3 .6 cfs * File: C: \1A\42-99\5IN .HYO Qmax 7.7 cf s POND-2 Version: 5.21 S/N: Page 5 EXECUTED: 11-22-1999 11:46:08 STORM # 2 Return Freq: 10 years Flow (cfs) 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 .------1-----1-----1-----1-----1-----1-----1-----1-----1-----1-----1- .05 .07 .09 .1 .12 .14 .15 .17 .19 . 2 .22 . 24 .26 .27 .29 1 -I I -I I -I I -I I -I .31 -I I .32 -I I .34 -I I .36 -I I I TIME (hrs) x x x x x * x x x * x x x x * * * * * * x x x x x x x x x x x x x x x x x x * * * x * x * x * x x x x x File: C:\lA\42-99\10 OUT .HYO * File: C:\lA\42-99\lOIN .HYO * * * * * * Qmax Qmax * * * * * * * * * * 4.0 cfs 8.7 cfs * * * * * * * * .05 .07 .09 .1 .12 . 14 .15 .17 .19 . 2 .22 .24 .26 .27 .29 .31 .32 .34 .36 POND-2 Version: 5.21 S/N: Page 6 EXECUTED: 11-22-1999 11:46:08 STORM # 3 Return Freq: 25 years Flow (cfs) 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 .------1-----1-----1-----1-----1-----1-----1-----1-----1-----1-----1- 1 -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I -I I I TIME (hrs) x x x x * x x x x * x x x * x x x * x * x x * * x x x x * * x x x x x x x x x * x* * x x x x x x x * * * * * * * * * * * * * * * * * * * * * * * * * * x File: C:\lA\42-99\25 OUT .HYO * File: C:\1A\42-99\25IN .HYO Qmax Qmax 4.4 cfs 9.9 cfs POND-2 Version: 5.21 S/N: Page 7 EXECUTED: 11-22-1999 11:46:08 STORM # 4 Return Freq: 50 years Flow (cfs ) 0.0 1. 5 3.0 4.5 6.0 7.5 9.0 10.5 12.0 13.5 15.0 16.5 ------1-----1 -----1-----1-----1-----1-----1-----1-----1-----1-----1- .05 x * x * .07 x * x * .09 x * x * .1 x * x * .12 x * x * .14 x * x * .15 -I x * I x * .17 -I x * I x * .19 -I x * I x * .2 -I x * I x * .22 -I x * I x * .24 -I x * I x * .26 -I x * I x * .27 x * x * .29 x * x * .31 x* *x .32 * x * x .34 * x * x .36 * x * x TIME (hrs) x File: C:\lA\42-99\50 OUT .HYO Qmax 4.9 cfs * File: C:\1A\42-99\50IN .HYO Qmax 11. 3 cfs POND-2 Version: 5.21 S/N: Page 8 EXECUTED: 11-22-1999 11:46:08 STORM # 5 Return Freq: 100 years Flow (cfs) 0.0 1.5 3.0 4.5 6.0 7.5 9.0 10.5 12.0 13.5 15.0 16.5 ------1-----1-----1-----1-----1-----1-----1-----1-----1-----1-----1- .05 .07 .09 .1 .12 . 14 .15 .17 .19 .2 .22 .24 .26 .27 .29 .31 .32 .34 .36 I -I I -I I -I I -I I -I I -I I -J I -I I I TIME (hrs) x File: * File: x x x x x * x x * x x x x * x x x * x x * x x * * x x x * x x x * x x x x x x * x * *x x x x x x x * * * * C:\lA\42-99\100 OUT .HYO C:\lA\42-99\lOOIN .HYO * * * * * * Qmax Qmax * * * * * * * * * * * * * * * * 5.1 cfs 11. 7 cfs Triangular Channel Analysis & Des i gn Open Channel -Uniform flow Worksheet Name: UNIVERSITY HEIGHTS Comment: OUTLET FLUME, FOR Q-100 Solve For Depth Given Input Data: Left Side Slope .. Right Side Slope. Manning's n ..... . Channel Slope ... . Discharge ....... . Computed Results: Depth ........... . Velocity ........ . Flow Area ....... . Flow Top Width .. . Wetted Perimeter. Critical Depth .. . Critical Slope .. . Froude Number ... . 4.00:1 (H:V) 4.00:1 (H:V ) 0.014 0 .0473 ft/ft 5.07 cfs 0.40 ft 7.78 fps 0.65 sf 3.23 ft 3 .33 ft 0 .63 ft 0.0044 ft/ft 3.05 (flow is Supercrit i cal) EXHIBIT 8 Open Channel Flow Module, Version 3.21 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 • Triangular Channel Analysis & Design Open Channel -Uniform flow Worksheet Name: UNIVERSITY HEIGHTS Comment: OUTLET FLUME, FOR Q-100 Solve For Depth Given Input Data: Left Side Slope .. Right Side Slope. Manning's n ..... . Channel Slope ... . Discharge ....... . Computed Results: Depth ........... . Velocity ........ . Flow Area ....... . Flow Top Width .. . Wetted Perimeter. Critical Depth .. . Critical Slope .. . Froude Number ... . 28.00:1 (H:V) 0.00:1 (H:V) 0.015 0.0600 ft/ft 3.99 cfs 0.23 ft 5.55 fps 0.72 sf 6.35 ft 6.58 ft 0.35 ft 0.0062 ft/ft 2.90 (flow is Supercritical) Open Channel Flow Module, Version 3.21 (c) 1990 EXHIBIT 9 Haestad Methods, Inc. * 37 Brookside Rd * Waterbury, Ct 06708