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SW1230602_Design Calculations_20230705
Stormwater Management Hydrology for Legacy Soccer Park Location: 520 Piney Ridge Road Forest City, NC 28043 Prepared by: DESTINATION LY DESIGN ........ CA -O 136 Furman Road, Ste. 6 ." F•• •� Boone, NC 28607 �' February 8, 2023 • �- = Revised: 06-15-23 • =;,�,9s.••P!Ngr••• ' ASS 2 G Table of Contents Inroduction 2 Methodology 2 Pre/Post-Development Analysis 2 Hydrologic Overview 2 POA 1 Pre/Post-Development Analysis 2 POA 2 Pre/Post-Development Analysis 3 Conclusion &Summary Tables 3 Figures Figure 1:Location Map Figure 2:FEMA Flood Panel Map Figure 3:Pre-development Drainage Map Figure 4:Post-development Drainage Map Appendix A: Calculations Curve Number(CN) Calculations TR-55 Time of Concentration Input Parameters/Calculations Wet Extended Detention&SCM Calculations Appendix B:Hydrograph Summary Data -1 - Introduction This report contains the stormwater impact analysis for The Legacy Soccer Park located at 520 Piney Ridge Road in Forest City,NC (Figure 1). Currently,the existing site contains open pasture and a few stands of trees. The proposed project will consist of multiple new soccer fields, a plaza area with buildings and mini fields, sidewalks, a maintenance building, associated parking areas,and new landscaping. The site is in the not in the floodplain according to NCDFIRM 3710153800J dated 07/02/08 (Figure 2). Methodology Valor Engineering used the NCDEQ Stormwater Design Manual,the North Carolina Erosion and Sediment Control Planning and Design Manual, and the North Carolina Division of Highways Guidelines for Drainage Studies and Hydraulic Design for all methodologies and design criteria. Destination by Design used the SCS method for all hydrographs and storage calculations, and time of concentrations (Tc)were calculated using Technical Release 55. All hydrographs were produced by Hydraflow Hydrographs®Version 2004 by InteliSolve and InRoads Civil Site Suite and Microsoft Excel were used for pipe and drainage structure analysis. For further details and methodology,refer to Appendix A for calculations and Appendix B for hydrographs. Pre/Post-Development Analysis Hydrologic Overview The project area may be considered as two drainage basins both prior to and after development. Points of Analysis (POA's) were established at downstream property locations where stormwater runoff is anticipated to leave the property or at critical locations in the stormwater system. These POA's remain in the same location pre to post-development and establish quantified reference points for all hydrologic analysis. All post-development peak flows (Qpeak) at the POA's are attenuated to be no greater than the pre-development Qpeak's for the 25-yr storm event. POA 1 Pre/Post-Development Analysis Prior to development, Basin 1 consists of open pasture,a portion of the existing subdivision (offsite) to the east,and a few tree stands. Currently, stormwater flows to the East where it enters an existing stream and leaves the site (POA 1). Post-development, Basin 1 is reduced in size and consists of a portion of the proposed landscape areas behind the back-of-curb, a portion of the existing subdivision(offsite) to the east, and a few tree stands. Because of the reduction in drainage basin area,all post- development Qpeak's at POA 1 were below the pre-development Qpeak's without the need for a stormwater pond. For a more detailed summary,refer to the summary tables under"Conclusion and Summary Tables." No proposed impervious area flows to this POA. -2- POA 2 Pre/Post-Development Analysis Prior to development, Basin 2 consists of open pasture,a portion of the existing subdivision (offsite) to the northwest, and a few tree stands. Currently, stormwater flows to the South where it enters an existing stream and leaves the site (POA 2). Post-development,Basin 2 is broken into two subbasins: Basin 2A,which drains to the Wet Extended Detention Pond, and Basin 2B,which by-passes the pond. Basin 2A shall include the new soccer fields,the plaza area with buildings and mini fields, sidewalks, the maintenance building,parking areas, and new landscaping. Basin 2B shall include the by-pass from the offsite subdivision to the Northwest and landscape areas. All post- development Qpeak's at POA 2 were attenuated below the pre-development Qpeak's. For a more detailed summary,refer to the summary tables under"Conclusion and Summary Tables." Conclusion & Summary Tables Valor Engineering concludes that the proposed development and the proposed Wet Extended Detention Pond will provide adequate storm water runoff attenuation and water quality. Table 1: Basin Area Summary Pre-Development Post-Development Basin ID Areas (Acres) Area (Acres) Basin 1 33.76 14.83 30.27 Basin 2 28.66 17.32 62.42 62.42 Table 2: Curve Number (CN) Summary Pre-Development Post-Development Basin ID CN CN Basin 1 61.3 62.3 Basin 2A 77.8 60.6 Basin 2B 60.7 Table 3: Time of Concentration,Tc Summary Pre/Post Pre/Post Pre/Post Pre- Post- Sheet Flow Shallow Channel Developed Developed Basin (min) Conc. Flow Flow (min) Tc (min) Tc (min) Basin 1 70.7 / 47.7 2.1 / 1.6 8.7 / 5.9 81.5 55.1 Basin 2A / 61.1 / 0.9 / 2.1 64.1 78.1 2.2 13.4 93.7 Basin 2B / 78.1 / 1.8 / 9.1 89.0 -3- Table 4: 24-hr Rainfalls Return 24-hour Period Rainfall 1 3.21 2 3.87 5 4.84 10 5.61 25 6.66 NOAA Atlas 14, Volume 2, Version 3 .,�, �,�''"�° `` ,. Location name: Forest City, North Carolina, USA" �'� i X I Latitude: 35.3285°, Longitude: -81.9083° 7oflA N • OP Elevation: 1027.28 ft** ,,orts di f *source: ESRI Maps '"N. :se "source: USGS •*,"' Table 5: Qpeak Summaries POA 1 Return Pre-Developed Post-Developed A Qpeak % Increase Period Flow (Qpeak/ Cfs) Flow (Qpeak/ cfs) (cfs) Qpeak 1 4.47 2.89 -1.58 -35.3% 2 8.61 5.53 -3.08 -35.8% 5 16.52 10.40 -6.12 -37.0% 10 23.90 14.85 -9.05 -37.9% 25 34.99 21.46 -13.53 -38.7% POA 2 Return Pre-Developed Post-Developed A Qpeak % Increase Period Flow (Qpeak, CfS) Flow (Qpeak/ CfS) (cfs) Qpeak 1 3.23 2.34 -0.89 -27.6% 2 6.30 4.36 -1.94 -30.8% 5 12.23 10.96 -1.27 -10.4% 10 17.84 15.66 -2.18 -12.2% 25 26.35 25.43 -0.92 -3.5% -4- Figures FIGURE 1: LOCATION MAP Proposed Site uollec- a vChrisimas (a'. • - r ICC Trail ----, c„Buifalc o'o,ags 0 Adaville Baptist Cemetery chi? © Supercenter9 Westwood Play&Learn RIM 0 �'Li57� ¢ MI P�J� r 8 TMobile9 eestawE _O E Brookdale Forest City9 Super China Buffet® pMelton Auto Sales " ® Staples e 6 4 r o i $ Hardin Rentals&Sales Q o R 9 Oakland Heightsz. Water Treatment 2 ;' i i Oakland HeR i +e l 0 6 Fine Line Auto Body9 a coer Ln The Community Pet Center Olive Meats Cheese Hightech Automotive e c 4 'aH 0 Tri City Baptist Church afa id rme o, 'v.3 o, & 6 e` �'9a d'dp� A o 0° % nvnl 1 Schoolhouse quilts Q a Go gle 9Qeek FIGURE 2: FEMA PANEL `��� • _ - -4 ,,.., A 1 Proposed Site . .....,.. i ea. , ".. . 4 IL lot, - I + II l�` - *, ►fir ` axe flag ' 'k k=11' -'.w.1. -I- 4 �r�.� ,444 emu ,r _'' ♦ -II 4 `�+y y j t, .:� I . . g. Flood Hazard Areas p. #.4, .• '• t , * �`,9 w., :ti' �; -v 1 Zone VE f _. r s� Zones A•A99,V s , , a.(- 4 .. 4.3, Zones AE•AH.AO.AE: 1%Annual Chance �. e V Flood Hazard Contained In Structure, 1% ..• r `yr Annual Chance Flood Hazard Conditions All _ 11, ��; ... ; r' ZoneAE:Floodway,1%Annual Chance •F# r.. '144. •; . r ! Flood Hazard Conditions:Floodway. 1% • Future Conditions Contained In Channel: • � :� �� ' • a .' _ Floodway / A ‘ • .� �� ! i ZoneAE:Community Encroachment Area, •4, r.�! ' F 1%Annual Chance Flood Hazard / ��,,:, r-1 ' . Conditions:Community Encroachment illImiihimillimillii. Area 0.2%Annual Chance Flood Hazard Contained In Channel.0.2%Annual Chance Flood Hazard Zone X: 1%Future Conditions.1%Future II Conditions Contained In Channel.X:1% Future Conditions Contained in Structure 1% Future Conditions Contained In Channel:Community Encroachment Area F/ Zone X: Protected By Levee Zone D Open Water Zone X i ft + " I iI / -V . - e i Irl wit A '... ... .... .... , ' /7:...77-.----7 -...._,:_ , ,-, .„, r 4".... ...........„.....,.._- ,,..o0 /":. W / a•��ffit_ 1•//'moo—e` ♦ �, PRE BASIN 1 f r------ . • . , st I 1t 1 , . ' , ,, -1-------------1 .... 1 ,. .. .....,.._ • 1 i .. :_. i . \i, 11 - F-4 ,‘ • )il 11 �- ril {\` if ._ �. ., /,-..-)L-:.! ' � � `' t &� �`�� , C,) 1 w.'-- 9 . 1 'PRE BASIN 2 /ie.�.. �l) 1 __ '. Ate, '>�' *rf ii _ r y. / •1,......,••• ---- 'N$ • - • * . i , 11,1;,,fir i ,. ....,. . a/ E„ ..„,... 1 1 . i.. . , 1 ..,. ..,- . k Ayr. 11.i,' / ii...:,7:,.,..,„,,...„...., ir l „......../ .... , ' r 1 / ' e ' 1Ir/�i/ '11/ ' :::-/:"' ' i i : i iiii„ b.,iii //( /. ': . ® i / A � Tc PATH / //5/{ • - BASIN DELINEATION a .` ._•' ' .. \ . . .. * ___ . . . brir* --•' '':-7:- ---.:' :--,,,-,-„,-„7,,. ..._,‘ yiik-**-.. • ,. maw i ,,,.-.4..------,_-____, • .. • -----_ -'' -'It.- -•>.- _ i , NN/.. of7 :ftzt r .. _ • , A I 41/1”/ lir r-;-:::-.4- ----w. '‘ f/4 .,_, '' '...: "lilt' oft'll( ::,\: . ,...r.;,k,,,iko--,,,‘;‘,.(4,,,'n•iii., :i. -=‘,404.1/,:/:!,.„. : ;,'. a .. ... ',. • ,‘Att - '`•• / -s"PSit` 41$ /if-,'• Pi. IN, - . . • 0.1 ----__ i F'14.1.1._---:-:::--1 .,tk. : ' ..:...-s, ,•••; ,,:', \\g 1 - t,oF ' ,j,„ . ijapiA.„-ti' t k‘ .. ..,i. ' . : filinky /I ' ' 'mit '..-•?.‘. ‘N,s•j.. ''1 Ni 0 Nied„pep.-.4,1 '4 if,:i , ------IfO. SfT BASIN 1 . ' I' 1111', ' 'Pz•ztutlivig ,tlf 4,- ...... ti,..-,,,,.. ( \----i777-F-,e,_i,,,-.4t,kvi p* ------ ....z . , 4., \..,„\', /4f.._\\ ,,,,4",i.,,,,.,„ .•,..,...-.......- .3 ' •'-'i •As , `....- )1 ' ,ri;p' y• givii!,1-7=4,0..4F -,--:-. ------,, .5 \\ x _.., \ -iv • :•,:iii0.;.por..... ..14,•gls,,,,t.. ..i'd.1 it*%\i•• •••:''.::, 2.k.....,, .: , ..t• ' . ./ NI Vino ) ei .,..„.... ...„,,!---' ".4 . ' ! •, ;) I II I NE, - : IA 4 4:-pi IN,- .'- i\1 \ i \x%\‘.. ---•\ 1 ,.! %;:l i -,,. ,- ..-.----....-- •*. 41,, " -c- =1--. ..t'a......r-' • - ,,,:L ,, i ...41,..,41.,..,, .it: -./:tii".147,:::;I::1;:71::::.; :,,L.. (....1'I - / 114, :v.! ,..../...!„. ..:".: .ill ,..., _,..,,, ..,.-- I 11\ I: ,.'' :7/... . ,_. ,... , . 1,..„,,,, POST BASIN 2A 7;1,Ortr' 1 •' \',11 : /..' . :.•':4: -,,',- .:.. or ' I ,, ,,, , , ,q . .-______, . ..„: .. • ,..,..,, L_,, ,, ,fki% Al , , ,f..-1-;--v•-.- ..--, A.- --- . -,,,,- '..,,,,. f; . : , . V to i,, ,7...-• ••:".••-•-'\\\\I) 1 I 1,1 ili -/,,,,,Viiiiiisi,,, rf, \ (z) 49 u) lift, . ' . , . " 110.S4 , ,# , ii• ,11-:_;:. •;..,::::‘‘ V\\ //4/4 .-4,...0 ,-41/.. ..:„:„....:4', 411, ' . .1114-41,31 tii, /-„-) 1 - --; . •-, , - . ., lif 111_,.,43,F- ; :- till it1171'' / ....-,,-„ii d--,-71,1*,,,__....elif •—___,g_- R, . 1 1 , 1 illir i si,' • , 1 rf I il,11 ' li, • -,,...----:----) : ,,,- • \‘, ---,.. ‘ ----,, - r' - 1st . . ,,,, i,„iii,1040 ,44, • , , .. . I POST BASIN 2B Vii /7/i, 1 , ' ' 1,4' It ' , ii,17/004/, ','/ , ifil ‘‘,'-' /1•7// 14hirlik r'''fr,' ') j'//7 04A2, ..,,,,,,:1-.72.E.::5.j..k.i ,ir/ ,' „.4,. /„!,,,,,4,,,,,, . ,,,,,„„,,,„,,,,,,/1/7- ,/ • • .1 / / / 'V° ,i . On / Tc PATH BASIN DELINEATION m IPH," . --------- 1 Appendix A: Calculations Calculations: Curve Number Calculations Curve Number Calculations: Pre- Development Pre Basin 1 Total Acres 33.76 Acres CN Impervious Surface 1.41 98.0 Existing Open Space (Good Condition) 25.10 61.0 Woods (Good) 7.25 55.0 Composite CN: 33.76 61.3 Pre Basin 2 Total Acres 28.66 Acres CN Impervious Surface 1.32 98.0 Existing Open Space (Good Condition) 17.21 61.0 Woods (Good) 10.13 55.0 Composite CN: 28.66 60.6 Curve Number Calculations: Post- Development Post Basin 1 Total Acres 14.83 Acres CN Existing Impervious Surface 1.16 98.0 Proposed Impervious Surface 0.00 98.0 Existing Open Space (Good Condition) 8.63 61.0 Proposed Disturbed Pervious Open Space 0.90 63.0 Woods (Good) 4.14 55.0 Composite CN: 14.83 62.3 Post Basin 2A Total Acres I 30.27 Acres CN Existing Impervious Surface 0.46 98.0 Proposed Impervious Surface 6.41 98.0 Existing Open Space (Good Condition) 1.68 61.0 Proposed Disturbed Pervious Open Space 24.31 63.0 Woods (Good) 0.89 55.0 Composite CN: 33.75 77.8 Post Basin 2B (By-Pass) Total Acres I 17.32 Acres CN Existing Impervious Surface 1.11 98.0 Proposed Impervious Surface 0.00 98.0 Existing Open Space (Good Condition) 6.84 61.0 Proposed Disturbed Pervious Open Space 1.31 63.0 Woods (Good) 8.06 55.0 Composite CN: 17.32 60.7 Calculations: Tc Calculations TR55 Tc Worksheet Hydraflow Hydrographs by Intelisolve Hyd. No. 1 PRE Basin 1 (PRE POA 1) Description A B C Totals Sheet Flow Manning's n-value = 0.600 0.240 0.011 Flow length (ft) = 200.0 150.0 0.0 Two-year 24-hr precip. (in) = 3.87 3.87 0.00 Land slope (%) = 1.50 2.00 0.00 Travel Time (min) = 52.76 + 17.95 + 0.00 = 70.71 Shallow Concentrated Flow Flow length (ft) = 350.00 0.00 0.00 Watercourse slope (%) = 3.00 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) = 2.79 0.00 0.00 Travel Time (min) = 2.09 + 0.00 + 0.00 = 2.09 Channel Flow X sectional flow area (sqft) = 3.00 0.00 0.00 Wetted perimeter (ft) = 5.00 0.00 0.00 Channel slope (%) = 2.00 0.00 0.00 Manning's n-value = 0.065 0.015 0.015 Velocity (ft/s) = 2.30 0.00 0.00 Flow length (ft) = 1200.0 0.0 0.0 Travel Time (min) = 8.69 + 0.00 + 0.00 = 8.69 Total Travel Time, Tc 81.48 min TR55 Tc Worksheet Hydraflow Hydrographs by Intelisolve Hyd. No. 2 PRE Basin 2 (PRE POA 2) Description A B C Totals Sheet Flow Manning's n-value = 0.600 0.240 0.011 Flow length (ft) = 200.0 200.0 0.0 Two-year 24-hr precip. (in) = 3.87 3.87 0.00 Land slope (%) = 1.50 1.50 0.00 Travel Time (min) = 52.76 + 25.35 + 0.00 = 78.11 Shallow Concentrated Flow Flow length (ft) = 300.00 0.00 0.00 Watercourse slope (%) = 2.00 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) = 2.28 0.00 0.00 Travel Time (min) = 2.19 + 0.00 + 0.00 = 2.19 Channel Flow X sectional flow area (sqft) = 3.00 0.00 0.00 Wetted perimeter (ft) = 5.00 0.00 0.00 Channel slope (%) = 1.50 0.00 0.00 Manning's n-value = 0.065 0.015 0.015 Velocity (ft/s) = 1.99 0.00 0.00 Flow length (ft) = 1600.0 0.0 0.0 Travel Time (min) = 13.37 + 0.00 + 0.00 = 13.37 Total Travel Time, Tc 93.67 min TR55 Tc Worksheet Hydraflow Hydrographs by Intelisolve Hyd. No. 4 POST Basin 1 (POST POA 1) Description A B C Totals Sheet Flow Manning's n-value = 0.600 0.240 0.011 Flow length (ft) = 175.0 125.0 0.0 Two-year 24-hr precip. (in) = 3.87 3.87 0.00 Land slope (%) = 3.00 4.00 0.00 Travel Time (min) = 35.93 + 11.76 + 0.00 = 47.69 Shallow Concentrated Flow Flow length (ft) = 300.00 0.00 0.00 Watercourse slope (%) = 4.00 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) = 3.23 0.00 0.00 Travel Time (min) = 1.55 + 0.00 + 0.00 = 1.55 Channel Flow X sectional flow area (sqft) = 3.00 0.00 0.00 Wetted perimeter (ft) = 5.00 0.00 0.00 Channel slope (%) = 2.00 0.00 0.00 Manning's n-value = 0.065 0.015 0.015 Velocity (ft/s) = 2.30 0.00 0.00 Flow length (ft) = 815.0 0.0 0.0 Travel Time (min) = 5.90 + 0.00 + 0.00 = 5.90 Total Travel Time, Tc 55.14 min TR55 Tc Worksheet Hydraflow Hydrographs by Intelisolve Hyd. No. 5 POST Basin 2A (to Pond) Description A B C Totals Sheet Flow Manning's n-value = 0.600 0.240 0.011 Flow length (ft) = 200.0 50.0 0.0 Two-year 24-hr precip. (in) = 3.87 3.87 0.00 Land slope (%) = 1.50 1.50 0.00 Travel Time (min) = 52.76 + 8.36 + 0.00 = 61.12 Shallow Concentrated Flow Flow length (ft) = 200.00 0.00 0.00 Watercourse slope (%) = 5.00 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) = 3.61 0.00 0.00 Travel Time (min) = 0.92 + 0.00 + 0.00 = 0.92 Channel Flow X sectional flow area (sqft) = 1.76 0.00 0.00 Wetted perimeter (ft) = 4.70 0.00 0.00 Channel slope (%) = 2.50 0.00 0.00 Manning's n-value = 0.010 0.015 0.015 Velocity (ft/s) = 12.20 0.00 0.00 Flow length (ft) = 1500.0 0.0 0.0 Travel Time (min) = 2.05 + 0.00 + 0.00 = 2.05 Total Travel Time, Tc 64.09 min TR55 Tc Worksheet Hydraflow Hydrographs by Intelisolve Hyd. No. 7 POST Basin 2B (By-Pass) Description A B C Totals Sheet Flow Manning's n-value = 0.600 0.240 0.011 Flow length (ft) = 200.0 200.0 0.0 Two-year 24-hr precip. (in) = 3.87 3.87 0.00 Land slope (%) = 1.50 1.50 0.00 Travel Time (min) = 52.76 + 25.35 + 0.00 = 78.11 Shallow Concentrated Flow Flow length (ft) = 300.00 0.00 0.00 Watercourse slope (%) = 3.00 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) = 2.79 0.00 0.00 Travel Time (min) = 1.79 + 0.00 + 0.00 = 1.79 Channel Flow X sectional flow area (sqft) = 3.00 0.00 0.00 Wetted perimeter (ft) = 5.00 0.00 0.00 Channel slope (%) = 2.50 0.00 0.00 Manning's n-value = 0.065 0.015 0.015 Velocity (ft/s) = 2.57 0.00 0.00 Flow length (ft) = 1400.0 0.0 0.0 Travel Time (min) = 9.07 + 0.00 + 0.00 = 9.07 Total Travel Time, Tc 88.96 min Calculations: Wet Extended Detention & SCM Calculations Pond Report Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:28 PM Pond No. 3 - POND Pond Data Pond storage is based on known contour areas.Average end area method used. Stage/Storage Table Stage(ft) Elevation(ft) Contour area(sqft) Incr.Storage(cuft) Total storage(cuft) 0.00 1016.00 13,480 0 0 1.00 1017.00 18,942 16,211 16,211 2.00 1018.00 22,543 20,743 36,954 3.00 1019.00 25,254 23,899 60,852 4.00 1020.00 28,078 26,666 87,518 5.00 1021.00 33,990 31,034 118,552 6.00 1022.00 36,643 35,317 153,869 7.00 1023.00 39,352 37,998 191,866 8.00 1024.00 42,117 40,735 232,601 9.00 1025.00 44,940 43,529 276,129 10.00 1026.00 47,819 46,380 322,509 11.00 1027.00 50,754 49,287 371,795 12.00 1028.00 53,746 52,250 424,045 Culvert/Orifice Structures Weir Structures [A] [B] [C] [D] [A] [B] [C] [D] Rise(in) = 36.00 3.00 6.00 6.00 Crest Len(ft) = 16.00 0.00 0.00 0.00 Span(in) = 36.00 3.00 18.00 18.00 Crest El.(ft) = 1026.50 0.00 0.00 0.00 No.Barrels = 1 1 1 1 Weir Coeff. = 3.33 0.00 0.00 0.00 Invert El.(ft) = 1015.00 1020.00 1023.00 1025.25 Weir Type = Riser --- --- --- Length(ft) = 100.00 0.00 0.00 0.00 Multi-Stage = Yes No No No Slope(%) = 2.00 0.00 0.00 0.00 N-Value = .010 .013 .013 .013 Orif.Coeff. = 0.60 0.60 0.60 0.60 Multi-Stage = n/a Yes Yes Yes Exfiltration= 0.000 in/hr(Contour) Tailwater Elev.= 0.00 ft Note:Culvert/Orifice outflows have been analyzed under inlet and outlet control. Elev(ft) Stage/ Discharge Elev(ft) 1030.00 1030.00 1028.00 1028.00 1026.00 - 1026.00 1024.00 1024.00 1022.00 1022.00 1020.00 1020.00 1018.00 1018.00 1016.00 1016.00 0.00 10.00 20.00 30.00 40.00 50.00 60.00 70.00 80.00 90.00 100.00 110.00 Total Q CuIv B CuIv C - Culy D Discharge(cfs) WeirA o 0 0 0 0 0 0 0 N OM co co N N cv N - = U O O O O O O O O p a)W p Crl 1 1 1 1 O ID 000 O O O O O O O O O 01 O 01 CO O cr � CO a) 0 O 01 Z • O Oi 0 CV 1 0 Z 0 O O O (0 T O O O 00 OD 113 011 01 O O O O O O O O W pM N th N N N O OO CO 0 0 0 0 0 0 0 is O O cocoO O O co U v ID 12 O O O O O O O O 01 W T T T T T T T T O ;0 , 1 o s I T .0 T O O O T O O --- GI 1 1 c, ci cc, f U N 0 1-.-, I I III U 0'1 7_ LH U7 L I 0 Z 4 0 Ci- ILI 1 n = In I- 0 0 0 o 0 co 0 0 0 cp o O coO O O O co W N N N (Ni O CO CO O O O COO O O O T T T T T T T T ---• .-1 = = ._. o o ^ _ .=. .3, co r-,,: 1 17'1 = •= 5 ' Lrl - 1- 7- 1- r-© a 0 .T. . © Lri• 0 ,- 01 g 4 171il I= 171(1) 0 X 0 40 0 0 1 0 47.• .0 0 0 0 . Q '1 . II 0)• • ci ci ci ci . 6 o o c, o o u 76 21= I,- 0') '=I r----4. A 94.3‘13 1.- - C‘.1 CO ,-, CO .7...i ,- 03 a) c• a) R a) 0 C11:=7' II".- Csi CNI .,- > E MI -7-7 CI 'V CV 01 -CC o 5. ± N.- CO ..l• CV LC) CO 0 CO ,01 C o O. 0 6. 07 Cri 5 ci c, 40 .:-', " . (1). cr 0,- ,-., . cr) c 65 _ u . .<.(,. ,.. u-) c. (... 1 .— 0, 0 , a) 'al al ..c ei l . 0 c 0 65 __, . ... . . . . _. 0 --.—....- r-- cci cri 6 cd >•-• ,- ,- ,- cv .... 0 Dolma. U-1 0 u.i I- IT IT T M Cri ._. '6 0) at Dolma, 0 • .,-. .... CO 03 , OD 11111111 ... cc 1.1-1 P. • CC CO CJI 0 LL I .=. .=. .-. '-' -I-. 17H. 0 NJ a) a o - o o -_, LL 1 1 = = = Permanent Pool Surface Area Calculations Wet Pond Drainage Area(A): 1,357,391 sf BUA(sf): 400,487 sf % Impervious(I): 29.5% Permanent Pool Average Depth 4 ft SA/DA(from Table) 0.94 Minimum Permanent Pool Surface Area: 12,759 sf Provided Permanent Pool Surface Area: 28,078 sf OK Water Quality Volume Calculations WQv=3630 x 1"x Rv x A(acres) Rv=0.05+0.009(I) Rv= 0.3155 Minimum Required WQv= 35,692 cf Provided WQv (Permanent Pool Volume) 87,518 cf OK Forebay Volume Calculations Forebay Volume: 14,860 cf Permanent Pool Volume 87,518 % Forebay Volume(15-20%): 16.98% OK Forebay Nonerosive Velocity Calculations Width of Weir: 6 ft Length of Weir: 48 ft Flow Rate for 1-inch Storm Event: 0.33 cfs Depth of Flow Over Weir: 0.0168 ft Flow Area: 0.8064 ft2 Velocity: 0.409 ft/sec OK Drawdown Time Calculations Q=CDA(2gHo)0.5 Q=Dischage(cfs) CD=Coefficient of discharge(unitless) A-Cross Sectional Area of orifice entrance(sf) g=Acceleration of gravity(32.2 ft/sec2) Ho-Driving Head from water surface to centroid of orifice(ft). **usually use Ho/ 3 to compute drawdown through an orifice to reflect the fact that the head is decreasing as drawdown occurs. CD= 0.6 Orifice Diameter(inches) 3 inches A= 0.04909 sf g= 32.2 ft/sec2 Ho= 1.075 ft Ho/ 3 (for drawdown) = 0.3583 Q= 0.14148 cf/sec Volume for drawdown(WQv) = 35,692 cf Drawdown Time in Seconds 252,271 sec Drawdown Time(2-5 days) 2.92 days OK Bouyant Force on any body is equal to the weight of the fluid displaced i Bouyant Force=Fz'-Fz(if=0,in equilibrium. ] Fz= Weight of Object Fz' = Weight of Fluid Displaced gwater= 62.4 lb/ft3 gconcrete= 145 lb/ft3 Riser Dimensions(Outside Width(W) = Length(L) = Height(H) = 10.5 Total Volume of Water Displaced= 262.5 Fz' = 16,380 Concrete Thickness(T) = i. 0.5 „F ItTotal Volume Of Concrete ,_;.' (exculding bottom) = 94.5 Orifice A Diameter(in) = 5 WEIR A FACE Orifice A Lost Force= 10 AREA / Orifice B Diameter(in) = 0 Orifice B Lost Force= 0 Outlet Pipe Diameter(in) = 36 II Outlet Pipe Lost Force= 512 Weir A Face Area(ft2) = 0.75 } Weir A Lost Force= 54.375 L Weir B Face Area(ft2) = 0.75 F BOTTOM OF POND Weir B Lost Force= 54.375 BConcrete Top on Riser? Yes • tq Additional Force from Top= 1812.5 Fz= 14,884 Fz'-Fz= 1,496 Status of Structure= Floating B(Additional Concrete Bottom) = 1.5 Additional Weight= 5437.5 New Fz'-Fz= -3941.39 OK!Not Floatil Appendix B : Hydrograph Summary Data Hydrograph Return Period Recap Hyd. Hydrograph Inflow Peak Outflow(cfs) Hydrograph No. type Hyd(s) description (origin) 1-Yr 2-Yr 3-Yr 5-Yr 10-Yr 25-Yr 50-Yr 100-Yr 1 SCS Runoff 4.47 8.61 16.52 23.90 34.99 PRE Basin 1 (PRE POA 1) 2 SCS Runoff 3.23 6.30 12.23 17.84 26.35 PRE Basin 2(PRE POA 2) 4 SCS Runoff 2.89 5.53 10.40 14.85 21.46 POST Basin 1 (POST POA 1) 5 SCS Runoff 19.93 28.45 41.77 52.76 68.09 POST Basin 2A(to Pond) 6 Reservoir 5 1.06 2.78 5.40 7.29 12.78 2A->Pond 7 SCS Runoff 2.02 3.94 7.65 11.15 16.45 POST Basin 2B(By-Pass) 8 Combine 6,7 2.89 4.94 11.67 16.45 25.54 POST POA 2 Proj. file: Forest City Hydrology Calcs.gpw Friday, Feb 17 2023, 10:06 AM Hydraflow Hydrographs by Intelisolve Hydrograph Summary Data: PRE POA 1 Pre Basin 1 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday,Feb 17 2023, 10:9 AM Hyd. No. 1 PRE Basin 1 (PRE POA 1) Hydrograph type = SCS Runoff Peak discharge = 4.47 cfs Storm frequency = 1 yrs Time interval = 2 min Drainage area = 33.760 ac Curve number = 61.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 81.50 min Total precip. = 3.21 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=56,532 cuft PRE Basin 1 (PRE POA 1) Q (cfs) Hyd. No. 1 -- 1 Yr 0 (cfs) 5.00 5.00 4.00 4.00 I 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 1 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday,Feb 17 2023, 10:9 AM Hyd. No. 1 PRE Basin 1 (PRE POA 1) Hydrograph type = SCS Runoff Peak discharge = 8.61 cfs Storm frequency = 2 yrs Time interval = 2 min Drainage area = 33.760 ac Curve number = 61.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 81.50 min Total precip. = 3.87 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=93,849 cuft PRE Basin 1 (PRE POA 1) Q (cfs) Hyd. No. 1 --2 Yr 0 (cfs) 10.00 10.00 8.00 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 1 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:9 AM Hyd. No. 1 PRE Basin 1 (PRE POA 1) Hydrograph type = SCS Runoff Peak discharge = 16.52 cfs Storm frequency = 5 yrs Time interval = 2 min Drainage area = 33.760 ac Curve number = 61.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 81.50 min Total precip. = 4.84 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume= 159,360 cuft PRE Basin 1 (PRE POA 1) Q (cfs) Hyd. No. 1 --5 Yr Q (cfs) 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 3.00 3.00 0.00 J 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 1 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday,Feb 17 2023, 10:9 AM Hyd. No. 1 PRE Basin 1 (PRE POA 1) Hydrograph type = SCS Runoff Peak discharge = 23.90 cfs Storm frequency = 10 yrs Time interval = 2 min Drainage area = 33.760 ac Curve number = 61.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 81.50 min Total precip. = 5.61 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=218,346 cuft PRE Basin 1 (PRE POA 1) Q (cfs) Hyd. No. 1 -- 10 Yr 0 (cfs) 24.00 r\ 24.00 20.00 20.00 16.00 16.00 12.00 12.00 8.00 8.00 4.00 4.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 1 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday,Feb 17 2023, 10:9 AM Hyd. No. 1 PRE Basin 1 (PRE POA 1) Hydrograph type = SCS Runoff Peak discharge = 34.99 cfs Storm frequency = 25 yrs Time interval = 2 min Drainage area = 33.760 ac Curve number = 61.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 81.50 min Total precip. = 6.66 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=306,379 cuft PRE Basin 1 (PRE POA 1) Q (cfs) Hyd. No. 1 -- 25 Yr 0 (cfs) 35.00 35.00 30.00 30.00 25.00 I 25.00 20.00 1 20.00 15.00 15.00 10.00 10.00 5.00 5.00 0.00 - 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 1 Time (hrs) Hydrograph Summary Data: POST POA 1 Post Basin 1 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:12AM Hyd. No. 4 POST Basin 1 (POST POA 1) Hydrograph type = SCS Runoff Peak discharge = 2.89 cfs Storm frequency = 1 yrs Time interval = 2 min Drainage area = 14.830 ac Curve number = 62.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 55.10 min Total precip. = 3.21 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=26,542 cuft POST Basin 1 (POST POA 1) Q (cfs) Hyd. No. 4 -- 1 Yr 0 (cfs) 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 4 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:12AM Hyd. No. 4 POST Basin 1 (POST POA 1) Hydrograph type = SCS Runoff Peak discharge = 5.53 cfs Storm frequency = 2 yrs Time interval = 2 min Drainage area = 14.830 ac Curve number = 62.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 55.10 min Total precip. = 3.87 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=43,391 cuft POST Basin 1 (POST POA 1) Q (cfs) Hyd. No. 4 --2 Yr 0 (cfs) 6.00 6.00 5.00 5.00 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 4 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:12 AM Hyd. No. 4 POST Basin 1 (POST POA 1) Hydrograph type = SCS Runoff Peak discharge = 10.40 cfs Storm frequency = 5 yrs Time interval = 2 min Drainage area = 14.830 ac Curve number = 62.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 55.10 min Total precip. = 4.84 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=72,722 cuft POST Basin 1 (POST POA 1) Q (cfs) Hyd. No. 4 -- 5 Yr Q (cfs) 12.00 12.00 10.00 10.00 8.00 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 J 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 4 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:12AM Hyd. No. 4 POST Basin 1 (POST POA 1) Hydrograph type = SCS Runoff Peak discharge = 14.85 cfs Storm frequency = 10 yrs Time interval = 2 min Drainage area = 14.830 ac Curve number = 62.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 55.10 min Total precip. = 5.61 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=98,976 cuft POST Basin 1 (POST POA 1) Q (cfs) Hyd. No. 4 -- 10 Yr Q (cfs) 15.00 15.00 12.00 12.00 9.00 I 9.00 6.00 6.00 3.00 3.00 0.00 J 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 4 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:12AM Hyd. No. 4 POST Basin 1 (POST POA 1) Hydrograph type = SCS Runoff Peak discharge = 21.46 cfs Storm frequency = 25 yrs Time interval = 2 min Drainage area = 14.830 ac Curve number = 62.3 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 55.10 min Total precip. = 6.66 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=137,992 cuft POST Basin 1 (POST POA 1) Q (cfs) Hyd. No. 4 -- 25 Yr Q (cfs) 24.00 24.00 20.00 20.00 16.00 16.00 12.00 12.00 8.00 8.00 4.00 4.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 4 Hydrograph Summary Data: PRE POA 2 Pre Basin 2 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:14 AM Hyd. No. 2 PRE Basin 2 (PRE POA 2) Hydrograph type = SCS Runoff Peak discharge = 3.23 cfs Storm frequency = 1 yrs Time interval = 2 min Drainage area = 28.660 ac Curve number = 60.6 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 93.70 min Total precip. = 3.21 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=45,303 cuft PRE Basin 2 (PRE POA 2) Q (cfs) Hyd. No. 2 -- 1 Yr 0 (cfs) 4.00 4.00 3.00 3.00 2.00 2.00 1.00 I 1.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 2 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:14 AM Hyd. No. 2 PRE Basin 2 (PRE POA 2) Hydrograph type = SCS Runoff Peak discharge = 6.30 cfs Storm frequency = 2 yrs Time interval = 2 min Drainage area = 28.660 ac Curve number = 60.6 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 93.70 min Total precip. = 3.87 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=76,068 cuft PRE Basin 2 (PRE POA 2) Q (cfs) Hyd. No. 2 --2 Yr 0 (cfs) 7.00 7.00 6.00 6.00 5.00 5.00 4.00 4.00 3.00 3.00 2.00 2.00 1.00 I 1.00 0.00 — 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 2 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:14 AM Hyd. No. 2 PRE Basin 2 (PRE POA 2) Hydrograph type = SCS Runoff Peak discharge = 12.23 cfs Storm frequency = 5 yrs Time interval = 2 min Drainage area = 28.660 ac Curve number = 60.6 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 93.70 min Total precip. = 4.84 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume= 130,392 cuft PRE Basin 2 (PRE POA 2) Q (cfs) Hyd. No. 2 --5 Yr Q (cfs) 14.00 14.00 12.00 12.00 10.00 10.00 8.00 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 J 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 2 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:14 AM Hyd. No. 2 PRE Basin 2 (PRE POA 2) Hydrograph type = SCS Runoff Peak discharge = 17.84 cfs Storm frequency = 10 yrs Time interval = 2 min Drainage area = 28.660 ac Curve number = 60.6 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 93.70 min Total precip. = 5.61 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume= 179,525 cuft PRE Basin 2 (PRE POA 2) Q (cfs) Hyd. No. 2 -- 10 Yr Q (cfs) 18.00 18.00 15.00 - 15.00 12.00 12.00 9.00 9.00 6.00 6.00 3.00 3.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 2 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:14 AM Hyd. No. 2 PRE Basin 2 (PRE POA 2) Hydrograph type = SCS Runoff Peak discharge = 26.35 cfs Storm frequency = 25 yrs Time interval = 2 min Drainage area = 28.660 ac Curve number = 60.6 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 93.70 min Total precip. = 6.66 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=253,081 cuft PRE Basin 2 (PRE POA 2) Q (cfs) Hyd. No. 2 -- 25 Yr Q (cfs) 28.00 28.00 24.00 24.00 20.00 20.00 16.00 16.00 12.00 12.00 8.00 8.00 4.00 4.00 0.00 J 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 2 Time (hrs) Hydrograph Summary Data: POST POA 2 Post Basin 2A->Pond 1 + Post Basin 2B Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:16 AM Hyd. No. 5 POST Basin 2A(to Pond) Hydrograph type = SCS Runoff Peak discharge = 19.93 cfs Storm frequency = 1 yrs Time interval = 2 min Drainage area = 30.270 ac Curve number = 77.8 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 64.10 min Total precip. = 3.21 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume= 140,267 cuft POST Basin 2A (to Pond) Q (cfs) Hyd. No. 5 -- 1 Yr Q (cfs) 21.00 21.00 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 3.00 3.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 5 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:16 AM Hyd. No. 5 POST Basin 2A (to Pond) Hydrograph type = SCS Runoff Peak discharge = 28.45 cfs Storm frequency = 2 yrs Time interval = 2 min Drainage area = 30.270 ac Curve number = 77.8 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 64.10 min Total precip. = 3.87 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume= 195,677 cuft POST Basin 2A (to Pond) Q (cfs) Hyd. No. 5 --2 Yr Q (cfs) 30.00 30.00 n 25.00 I 25.00 L 20.00 20.00 15.00 15.00 10.00 1 10.00 5.00 5.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:16 AM Hyd. No. 5 POST Basin 2A (to Pond) Hydrograph type = SCS Runoff Peak discharge = 41.77 cfs Storm frequency = 5 yrs Time interval = 2 min Drainage area = 30.270 ac Curve number = 77.8 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 64.10 min Total precip. = 4.84 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=283,030 cuft POST Basin 2A (to Pond) Q (cfs) Hyd. No. 5 -- 5 Yr Q (cfs) 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:16 AM Hyd. No. 5 POST Basin 2A (to Pond) Hydrograph type = SCS Runoff Peak discharge = 52.76 cfs Storm frequency = 10 yrs Time interval = 2 min Drainage area = 30.270 ac Curve number = 77.8 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 64.10 min Total precip. = 5.61 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=355,860 cuft POST Basin 2A (to Pond) Q (cfs) Hyd. No. 5 -- 10 Yr Q (cfs) 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 I 20.00 10.00 10.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:16 AM Hyd. No. 5 POST Basin 2A(to Pond) Hydrograph type = SCS Runoff Peak discharge = 68.09 cfs Storm frequency = 25 yrs Time interval = 2 min Drainage area = 30.270 ac Curve number = 77.8 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 64.10 min Total precip. = 6.66 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=458,596 cuft POST Basin 2A (to Pond) Q (cfs) Hyd. No. 5-- 25 Yr Q (cfs) 70.00 70.00 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 5 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:28 PM Hyd. No. 6 2A-> Pond Hydrograph type = Reservoir Peak discharge = 0.87 cfs Storm frequency = 1 yrs Time interval = 2 min Inflow hyd. No. = 5 Max. Elevation = 1023.20 ft Reservoir name = POND Max. Storage = 200,021 cuft Storage Indication method used. Wet pond routing start elevation=1020.00 ft. Hydrograph Volume=110,956 cuft 2A -> Pond Q (cfs) Hyd. No. 6 -- 1 Yr Q (cfs) 21.00 21.00 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 3.00 3.00 0.00 l 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) Hyd No. 6 Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:29 PM Hyd. No. 6 2A-> Pond Hydrograph type = Reservoir Peak discharge = 2.53 cfs Storm frequency = 2 yrs Time interval = 2 min Inflow hyd. No. = 5 Max. Elevation = 1023.59 ft Reservoir name = POND Max. Storage = 215,735 cuft Storage Indication method used. Wet pond routing start elevation=1020.00 ft. Hydrograph Volume=165,541 cuft 2A -> Pond Q (cfs) Hyd. No. 6 --2 Yr 0 (cfs) 30.00 30.00 I 25.00 25.00 20.00 20.00 15.00 15.00 10.00 10.00 5.00 5.00 0.00 J 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) — Hyd No. 6 Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:29 PM Hyd. No. 6 2A-> Pond Hydrograph type = Reservoir Peak discharge = 4.75 cfs Storm frequency = 5 yrs Time interval = 2 min Inflow hyd. No. = 5 Max. Elevation = 1024.64 ft Reservoir name = POND Max. Storage = 260,236 cuft Storage Indication method used. Wet pond routing start elevation=1020.00 ft. Hydrograph Volume=251,905 cuft 2A -> Pond Q (cfs) Hyd. No. 6 -- 5 Yr 0 (cfs) 50.00 50.00 40.00 S 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 / 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) — Hyd No. 6 Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:29 PM Hyd. No. 6 2A-> Pond Hydrograph type = Reservoir Peak discharge = 6.92 cfs Storm frequency = 10 yrs Time interval = 2 min Inflow hyd. No. = 5 Max. Elevation = 1025.56 ft Reservoir name = POND Max. Storage = 302,003 cuft Storage Indication method used. Wet pond routing start elevation=1020.00 ft. Hydrograph Volume=323,608 cuft 2A -> Pond Q (cfs) Hyd. No. 6 -- 10 Yr Q (cfs) 60.00 60.00 50.00 50.00 40.00 40.00 30.00 i 30.00 20.00 20.00 10.00 10.00 0.00 ' I \ 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) — Hyd No. 6 Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:29 PM Hyd. No. 6 2A-> Pond Hydrograph type = Reservoir Peak discharge = 13.74 cfs Storm frequency = 25 yrs Time interval = 2 min Inflow hyd. No. = 5 Max. Elevation = 1026.63 ft Reservoir name = POND Max. Storage = 353,638 cuft Storage Indication method used. Wet pond routing start elevation= 1020.00 ft. Hydrograph Volume=425,398 cuft 2A -> Pond Q (cfs) Hyd. No. 6 -- 25 Yr Q (cfs) 70.00 70.00 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 i 10.00 10.00 21 0.00 - 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) Hyd No. 6 Hyd No. 5 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:19AM Hyd. No. 7 POST Basin 2B (By-Pass) Hydrograph type = SCS Runoff Peak discharge = 2.02 cfs Storm frequency = 1 yrs Time interval = 2 min Drainage area = 17.320 ac Curve number = 60.7 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 89.00 min Total precip. = 3.21 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=27,484 cuft POST Basin 2B (By-Pass) Q (cfs) Hyd. No. 7 -- 1 Yr 0 (cfs) 3.00 3.00 2.00 2.00 1.00 1.00 1 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 7 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:19AM Hyd. No. 7 POST Basin 2B (By-Pass) Hydrograph type = SCS Runoff Peak discharge = 3.94 cfs Storm frequency = 2 yrs Time interval = 2 min Drainage area = 17.320 ac Curve number = 60.7 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 89.00 min Total precip. = 3.87 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=46,070 cuft POST Basin 2B (By-Pass) Q (cfs) Hyd. No. 7 --2 Yr 0 (cfs) 4.00 4.00 3.00 3.00 2.00 2.00 1.00 - 1.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Time (hrs) — Hyd No. 7 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:19AM Hyd. No. 7 POST Basin 2B (By-Pass) Hydrograph type = SCS Runoff Peak discharge = 7.65 cfs Storm frequency = 5 yrs Time interval = 2 min Drainage area = 17.320 ac Curve number = 60.7 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 89.00 min Total precip. = 4.84 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=78,861 cuft POST Basin 2B (By-Pass) Q (cfs) Hyd. No. 7 -- 5 Yr Q (cfs) 8.00 8.00 I 6.00 6.00 4.00 4.00 2.00 2.00 0.00 J 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 7 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:19AM Hyd. No. 7 POST Basin 2B (By-Pass) Hydrograph type = SCS Runoff Peak discharge = 11.15 cfs Storm frequency = 10 yrs Time interval = 2 min Drainage area = 17.320 ac Curve number = 60.7 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 89.00 min Total precip. = 5.61 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume= 108,501 cuft POST Basin 2B (By-Pass) Q (cfs) Hyd. No. 7 -- 10 Yr Q (cfs) 12.00 12.00 10.00 10.00 8.00 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 7 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Friday, Feb 17 2023, 10:19AM Hyd. No. 7 POST Basin 2B (By-Pass) Hydrograph type = SCS Runoff Peak discharge = 16.45 cfs Storm frequency = 25 yrs Time interval = 2 min Drainage area = 17.320 ac Curve number = 60.7 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 89.00 min Total precip. = 6.66 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Hydrograph Volume=152,853 cuft POST Basin 2B (By-Pass) Q (cfs) Hyd. No. 7 -- 25 Yr Q (cfs) 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 3.00 I 3.00 0.00 - 0.00 0 3 5 8 11 13 16 19 21 24 27 Hyd No. 7 Time (hrs) Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:35 PM Hyd. No. 8 POST POA 2 Hydrograph type = Combine Peak discharge = 2.34 cfs Storm frequency = 1 yrs Time interval = 2 min Inflow hyds. = 6, 7 Hydrograph Volume= 138,440 cuft POST POA 2 Q (cfs) Hyd. No. 8 -- 1 Yr O (cfs) 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) Hyd No. 8 Hyd No. 6 Hyd No. 7 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:35 PM Hyd. No. 8 POST POA 2 Hydrograph type = Combine Peak discharge = 4.36 cfs Storm frequency = 2 yrs Time interval = 2 min Inflow hyds. = 6, 7 Hydrograph Volume=211,610 cuft POST POA 2 Q (cfs) Hyd. No. 8 --2 Yr Q (cfs) 5.00 5.00 4.00 J 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) Hyd No. 8 Hyd No. 6 Hyd No. 7 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:35 PM Hyd. No. 8 POST POA 2 Hydrograph type = Combine Peak discharge = 10.96 cfs Storm frequency = 5 yrs Time interval = 2 min Inflow hyds. = 6, 7 Hydrograph Volume=330,766 cuft POST POA 2 Q (cfs) Hyd. No. 8 -- 5 Yr Q (cfs) 12.00 12.00 10.00 10.00 8.00 8.00 6.00 6.00 4.00 1 4.00 2.00 2.00 0.00 '' 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) Hyd No. 8 Hyd No. 6 Hyd No. 7 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:36 PM Hyd. No. 8 POST POA 2 Hydrograph type = Combine Peak discharge = 15.66 cfs Storm frequency = 10 yrs Time interval = 2 min Inflow hyds. = 6, 7 Hydrograph Volume=432,109 cuft POST POA 2 Q (cfs) Hyd. No. 8 -- 10 Yr Q (cfs) 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 3.00 3.00 0.00 0.00 0 10 19 29 39 48 58 68 77 87 97 Time (hrs) Hyd No. 8 Hyd No. 6 Hyd No. 7 Hydrograph Plot Hydraflow Hydrographs by Intelisolve Thursday,Jun 15 2023,4:36 PM Hyd. No. 8 POST POA 2 Hydrograph type = Combine Peak discharge = 25.43 cfs Storm frequency = 25 yrs Time interval = 2 min Inflow hyds. = 6, 7 Hydrograph Volume=578,252 cuft POST POA 2 Q (cfs) Hyd. No. 8 -- 25 Yr Q (cfs) 28.00 28.00 24.00 24.00 20.00 20.00 16.00 16.00 12.00 12.00 8.00 8.00 4.00 4 ---\N--r 4.00 0.00 0.00 0 9 17 26 35 43 52 61 69 78 87 95 Time (hrs) Hyd No. 8 — Hyd No. 6 Hyd No. 7