Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
WPO202100046 Calculations 2022-08-19
Barnes Lumber ALBEMARLE COUNTY, VIRGINIA WPO PLAN DESIGN CALCULATIONS & NARRATIVE DECEMBER 16, 2020 REVISED JUNE 289 2021 REVISED AUGUST 18, 2022 �,.••0 TIMMONS GROUP YOUR VISION ACHIEVED THROUGH OURS. Prepared by: Clint Shifflett, PE Timmons Group 608 Preston Avenue, Suite 200 Charlottesville, VA 22903 434.327.1690 nF CLINT W. 2' S FFLET s Lic. N 54380 UGC' 8/18/2022 _.a4 At Table of Contents Section Title 1. Project Narrative 2. LD-204 Inlet Calculations 3. LD-229 Pipe Calculations 4. LD-347 Hydraulic Grade Line Analysis 5. Pre -Developed HydroCAD Calculations 6. Post -Developed HydroCAD Calculations 7. Outlet Protection Sizing 8. Virginia Runoff Reduction Method Worksheet Summary Project Narrative: This project includes the construction of multiple roads, mixed use pad sites, associated utilities and landscaping. The project will be developed in multiple phases. Phase 1 will include the construction of 3 roads, rough grading and the stormwater management pond. The limits of disturbance for phase 1 is 10.49 acres. Water Quality: The current site is developed with multiple buildings and asphalt and concrete paving. The site was analyzed in the post development condition for the work to be done in Phase 1. The pre -developed TP load is 10.31 lb/yr. The post developed TP load is 0.05 lb/yr. Nutrient credits shall be purchased for the remaining 3.19 lb/yr required to be removed. Water Quantity: The proposed stormwater conveyance system currently outfalls to 3 locations. Outfall 1 is the existing storm sewer system in Library Ave to the west. Outfall 2 is to an existing stream to the southeast. Outfall 3 is across the railroad tracks to the north. Each outfall was analyzed for the energy balance and 10-year storm individually. Outfall 1 and 3 meet the energy balance by a reduction in area resulting in a reduction in flow. An underground detention system is proposed for Outfall 2 to detain the 1-year, 24-hour storm to meet the requirements of the energy balance equation for Outfall 2. Additionally, the 10-year, 24-hr storm is being detained to less than the pre -developed 10-year, 24-hour storm to meet flood protection requirements. The underground detention facility is currently sized for Phase 1 only. Separate stormwater facilities will be provided for the future road work and the development of the parcels. Alternatively, the underground detention facility could be expanded to provide water quantity for the parcels. Pipe calculations were provided with an assumed C-factor of 0.85 for the parcel area to ensure capacity to the underground detention. Inlet spread calculations use Phase 1 drainage areas and C-factors. FORM L02N STORMWATER INLET COMPUTATIONS SHEET 1 OF ROUTE PROJECT CROZ TSOUARE DESIGNER: A. RARNES DATE VNom CHECKED: UNITSAGUSH mmm�mmmo®om��mm®mmm®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmm�mmmmmmmmmmmomm�m�mmm�m� �mm�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m� mmm�mmmmo�o®��®mmm®mm®mmmmmm�mmmm��m� �mm�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m� mmm�mmmmomom��mm�mmm®mmmm®mmm®mm��m� �mm�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomom��mmmmmm®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmm�mmmmmmmmmmm®mmmmmmm�mtm� m�m�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomommmmmmmmmmmmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmm�mmmmmmmmmmm©mmmmmmm�®mmm ®mm�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m� mmm�mmmmomommmmm�®mmmmmmm®mmmmmm��m� ®mm�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomomm�®mmmmm®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmmommmmmm®�mtm� �m®�®m�mmmmmmmmmmmmmmmmmmmmmmmmm��m mmmm�mmmomommmmmm®mm®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmm®mmmmmm®��®� �mm�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m� mmm�mmmmomom��mm�mmm®mmmmmmmmmmm��m� �mm�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomomm�mm®mmm®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmmammmm®m®�®mmm ©m®�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mmmomomm�mmmmmm®mmmmmmmmmmm��m mmm�mmm0000mmmmmmmmmmmmmmmmmmmmm��m mmm�mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmtm� ®mm�mm�mmmmmmmmmmmmmmmmmmmmmmmmm��m� mmm�mmmmomom��mm�mmm®mmmmmmmmmmm��m� �mm�mmmmmmmmmmmmmmmmmmmmmmmmmmmm��m mmm�mm�o�om��mmmmmm®mmmmmmmmmmm��m INLETSOFT RY ENSOFTEC DATE: WK OU FORM L02N STORMWATER INLET COMPUTATIONS SHEEf20F2 ROUTE PROJECT CROZ TSOUARE DESIGNER: A. RARNES DATE VNom CHECKED: UNITSAGUSH INLEfSOFT RY ENSOFTEC DATE: WK OU 38593-Prop_STRM-100 STORM SEWER DESIGN COMPUTATIONS STORM FREQUENCY 70 PROJECT: Barnes LOCATION: COUNTY: Designed by: J. Denko Checked by: UNITS ENGLISN PIPE NO FROM POINTIN TO POT DRAM. AREA "A" Acre (3) RUNOFF COEFF. "C (4) CA TOTAL INLET TIME Minutes (9) RAM FALL 1n (8) RUNOFF Q CPS (9) INVERTELEVATIONS LENGTH of Pipe Ft (12) SLOPE Ft/Ft. (13) SIZE (Dia. Or Span([s) aCPS (14) SHAPE Capacity (15) Friction Slope Ftfft VEL V. PUS. (16) FLAW UME Min (17) REMARKS (18) MCACCUM- RE- MENT (5) ULATED (6) ADDTL CA UPPER END (10) LOWER END (11) REFERENCE (1) STA. REFERENCE (2) STA. 101 102 100 0-OW 0-OW 0-OW 665E 4650 0-0W 9940 36921 66400E 663266 95-833 0-009 48-WO Circular @5965 0-001 8&913 0183 309 310 308 0050 0850 0043 OM3 000E 600E 5608 0238 712.1% 911690 52025 0010 15 WO Circular 6458 0DW 2.510 0.M5 309 308 306 0080 0.890 0-090 0112 0-0W 6345 5519 0619 71151E 91084E 73024 0_010 15000 Cicular 6458 0000 3330 0365 305 306 304 0000 O.OW 0-0W 0112 0-000 6911 5428 0608 210940 909MI 139899 0_010 15000 Cicular 6458 0000 3314 0904 303 304 302 0510 0.850 0495 0599 0000 9415 5263 3140 909240 908-800 44000 D_010 18000 CimWar 10502 0001 5201 0141 301 302 230 0220 0.850 0189 0984 OAW 9556 5231 4.0" 708900 908-MO 62829 D010 18000 CimWar 10961 0002 5689 0-184 239 238 236 0210 0850 0.199 0199 OAO0 6-DOE 5608 1.001 913529 913309 43999 0005 15000 Circular 4566 0000 2988 0245 235 236 232 0.10E 0850 0085 026E 0.000 6245 55" 1461 91321E 711.310 108037 0018 15000 Circular 8564 0001 5219 0.M5 233 234 232 0240 0850 0204 020E 0.000 600E 5608 1.1" 911750 711.310 4600E 0010 1500E Circular 6458 0000 3.998 0.184 231 232 230 0090 08W 0077 0545 OAO0 6590 5459 2994 91121E 909060 118909 0_018 15 WO Circular $691 0002 6429 0308 229 1 230 1 226 1 000E 1 O.OW 000E 1329 1 OAO0 1 9940 5190 6895 1 907940 906308 1 207773 1 D_008 2400E Ctmdml 20044 1 0001 580E 0599 229 228 226 1040 0.850 0.884 0.884 OAO0 6-OW 5608 4959 906.800 906580 43998 0-005 18WO Circular 7426 0002 4510 0-163 225 226 224 0.190 0.850 0145 2359 OAO0 8339 5-062 11.932 70621E 902290 225155 0-019 24 WO Circular 29923 0003 9006 0419 223 224 220 0.120 0.850 0102 2459 OAO0 8953 4998 12240 90229E 6"398 114.969 0-025 24WO Circular 35965 0003 10335 0-185 221 222 220 0850 0.850 0.923 0723 OAW 6-OW 5608 4.051 699320 6W880 43999 0010 18WO Circular 10502 0001 55/1 0132 219 no 218 0.100 0.890 0089 3269 OAW 8-939 4941 16149 699980 688990 240235 0-038 24WO Circular 43806 0005 12913 0310 219 218 214 0130 0850 0111 3399 OAW 9249 4881 16492 688690 682190 129945 0050 24WO Circular 50-590 0005 14428 0.150 215 216 214 134E 0850 1139 1139 OAO0 6-0W 5608 6389 684.84E 683-063 44426 0040 15 WO Circular 12916 0010 10519 0090 213 214 200 0110 0860 0-095 4613 OAO0 93" 4852 22382 682090 67180 99-889 0049 24WO Circular 50-048 0010 15519 0.109 211 212 200 0470 0.850 04M 0400 OAO0 6-OW 5608 2240 697545 696191 6393210H W0 CimWar 9400 0001 6296 0.169 201 2W 202B 000E 0OW OOW 5012 0.00E 9506 4832 2422E 6594E 692.5❑ 121.175 WO Circular 57994 0003 11.306 0.199 205 206 204 0090 0850 OAP 007 OAO0 60W 5608 0429 63372 693230 211W WO Circular 4.566 00W 2.341 0203 203 204 202 0050 0850 0-043 0119 OAO0 6203 5555 0661 63.135 6T2919 83-039 WO Cicular 44566 O.OW 2655 0521 2W 210 208 1700 0850 1445 1445 0000 6-OW 5608 8103 65991 695M2 199388WO Cicular 13900 0006 8184 0041 209 208 202 0850 0850 0923 2168 0-OW 6-041 55W 12131 65040 674.049 440338 WO Cicular 15953 0013 9.859 0094 201E 202 202B 0.100 0850 0085 2.3T2 0000 6R4 5425 12.865 625❑ 691299 22.804 WO CimWar 95.599 0001 13.600 0028 201A 202E 202A 0000 DEW DEW 7384 0-OW 9685 4999 35435 669993 667000 19333_WO Circular 164.06E 0009 26T21 0011 401 1 402 1 1 400 1 1 114E 1 030E 1 0342 1 0M2 1 0-On) 1 6-OW 1 5608 1 1918 1 660994 1 660-856 1 193" 0-009 12W0 Circular 2999 0-003 406E 0-080 503 504 502B 4210 0850 3519 3599 0-000 6-OW 6160 22044 6995W 665960 2W102 0-040 24_000 Cimular 44993 0-009 1 14299 0M3 501E 502E 502A 0990 0850 06P 4250 0000 6353 6088 25.874 665864 665095 98.899 0010 30000 CimWar 41.015 0004 8.854 0. 149 501A 502A 500 0000 0000 0000 4250 0.000 6505 6040 25670 664970 NA711 25.860 0010 30000 CimWar 41.015 0004 8.838 0M9 38593-Pmp STRM-100 PROJECT: Bames DESIGNED BY: J. Denko HYDRAULIC GRADE LINE ANALYSIS Checked: INCIDENCE PROBABILITY 10 Year INLET INLET OUTLET WATER OIA PIPE DESIGN OISGH. LENGTH PIPE FRICTION SLOPE, SIO FRICTION LOaG JUNCTION LOSS FINAL INet Waled RM f.Onni¢nb 1.3 0.5 OR GTATION SURFACE Do Oo Lo Hf V. Ho OI N OM N'32g HI HI HI H Sums E. JUNCTION EIEV. (In) (CFS) (Ft) (FT/M (Ft) (Ft) (Ft) E1.11. 102 666.47 1 48 36.92 95.83 0.07% O.Of 8.]1 0.29 0 0 0 0 0 0 0 0.29 0 TRUE 1 0.21 1 666.68 202B 670.88 30 35.43 17.33 0.75% 0.13 26.72 2.]] 24.22 11.31 273.82 1.98 0.69 63.12 1.61 5.07 0 TRUE 2.67 673.55 682.99 OK -9.44 200 674.52 30 24.22 121.18 0.35% 0.42 11.31 0.5 22.38 15.52 347.34 3.74 1.31 0.55 0 1.81 0 TRUE 1.33 675.84 686.02 OK -10.18 214 6]8.]8 24 22.38 99.89 0.98% 0.98 15.52 0.93 16.49 14.43 237.95 3.23 1.13 87.55 1.2 3.27 0 TRUE 2.61 681.39 690.44 OK -9.04 218 683.T 24 16.49 129.94 0.53% 0.69 14.43 0.81 16.15 12.91 208.53 2.59 0.91 3.1 0 1.71 0 TRUE 1.55 685.32 695.75 OK -10.43 220 690.37 24 16.15 240.24 0.51% 1.22 12.91 0.65 12.24 10.33 126.5 1.66 0.58 92.17 0.34 1.57 0 TRUE 2.01 692.38 705.54 OK -13.16 224 701 24 12.24 114.87 0.29% 0.34 10.33 0.41 11.93 9.01 107.46 1.26 0.44 2.5 0 0.86 0 TRUE 0.76 ]01.]6 709.52 OK -].]6 226 ]03.8] 24 11.93 225.16 0.28% 0.63 9.01 0.31 6.89 5.8 39.99 0.52 0.18 92.13 0.22 0.72 0 TRUE 0.99 704.86 713.39 OK -8.54 230 ]0].91 24 6.89 207.T 0.09% 0.19 5.8 0.13 4.1 5.69 23.32 0.5 0.18 ]0.]5 0.31 0.61 0 TRUE 0.5 708.41 716.91 OK -8.5 302 709.24 18 4.1 62.83 0.15% 0.1 5.69 0.13 3.14 5.2 16.33 0.42 0.15 99.63 0.29 0.57 0.74 TRUE 0.46 ]09.] 716.5 OK -6.79 304 710 18 3.14 44 0.09% 0.04 5.2 0.11 0.61 3.31 2.02 0.17 0.06 86.66 0.12 0.28 0.37 TRUE 0.22 710.22 716.5 OK -6.27 306 ]10.34 15 0.61 139.9 0.01% 0.01 3.31 0.04 0.62 3.33 2.06 0.1] 0.06 9].8] 0.12 0.22 0 TRUE 0.12 ]10.4] ]1].]4 OK -].28 308 ]11.84 15 0.62 ]3.02 0.01% 0.01 3.33 0.D4 0.24 2.51 0.6 0.1 0.03 89.61 0.0] 0.15 0.19 TRUE 0.1 ]11.94 ]18.53 OK -6.59 310 ]12.6] 15 0.24 52.02 1 0.00% 0 2.51 0.02 0 0 1 0 1 0 1 0 1 0 1 0 1 0.02 1 0.03 1 TRUE 0.02 1 712.69 ]18.53 1 OK -5.84 202 1 1 673.55 30 1 12.86 1 22.8 1 0.10% 0.02 1 13.6 1 0.72 12.13 1 9.86 1 119.58 1 1.51 0.53 1 64.13 1 0.84 2.09 1 0 1 TRUE 1 1.07 674.61 1 682.15 1 OK -7.54 204 1 1 674.61 1 15 1 0.66 1 83.04 1 0.01% 1 0.01 1 2.65 1 0.03 1 0.43 1 2.34 1 1 1 0.09 1 0.03 1 87.23 1 0.06 1 0.12 1 0.15 1 TRUE 1 0.08 1 6]4.] 1 679.93 1 OK -5.23 206 1 1 6]4.] 1 15 1 0.43 1 28.46 1 0.00% 1 0 1 2.34 1 0.02 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0.02 1 0.03 1 TRUE 1 0.02 1 6]4.]1 1 6]9.9] 1 OK -5.26 208 675.25 18 12.13 44.03 1.33% 0.59 9.86 0.38 8.1 8.18 66.31 1.04 0.36 18.65 0.26 1 1.3 TRUE 1.24 676.49 682.2 OK -5.]2 210 676.84 18 8.1 19.94 0.60% 0.12 8.18 0.26 0 0 0 0 0 0 0 0.26 0.34 TRUE 0.29 M13 680.18 OK -1 AR 212 6]].19 15 2.24 63.93 0.12% 0.08 6.3 0.15 0 0 0 0 0 0 0 0.15 0.2 TRUE 0.18 M37 68].]6 OK -10.39 216 684.06 15 6.39 44.43 0.98% 0.43 10.52 0.43 0 0 0 0 0 0 0 0.43 0.56 TRUE 0.71 684.78 690.44 OK 222 699.08 18 4.05 44 0.15% 0.07 5.57 0.12 0 0 0 0 0 0 0 0.12 0.16 TRUE 0.14 699.22 705.54 OK 228 707.78 18 4.96 44 0.22% 0.1 4.51 0.08 0 0 0 0 0 0 0 0.08 0.1 TRUE 0.15 ]0].93 713.39 OK 232 1 1 710.06 15 1 2.97 1118.711 0.21% 0.25 1 6.43 1 0.16 1.46 1 5.22 1 7.62 1 0.42 0.15 1 95.01 1 0.17 0.48 1 0 1 TRUE 1 0.49 710.55 1 ]18.]8 1 OK -8.23 236 1 1 712.31 1 15 1 1.46 1108.Nl 0.05% 1 0.06 1 5.22 1 0.11 1 1 1 2.99 1 2.99 1 0.14 1 0.05 1 90 1 0.1 1 0.25 1 0.33 1 TRUE 1 0.22 1 712.53 1 720.63 1 OK -8.1 238 1 1 714.31 1 15 1 1 1 44 1 0.02% 1 0.01 1 2.99 1 0.03 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0.03 1 0.05 1 TRUE 1 0.03 1 714.34 1 720.62 1 OK -6.28 234 712.31 15 1.14 44 1 0.03% 0.01 3.98 0.06 0 0 0 0 0 0 0 0.06 0.08 TRUE 0.05 712.36 ]18.]8 OK 402 661.66 12 1.92 19.38 1 0.29% 0.06 4.06 0.06 0 0 0 0 0 0 0 0.06 0.08 FALSE 0.14 661.8 662.16 OK 502A 1 1 670.88 30 1 25.67 1 25.86 1 0.39% 0.1 1 8.84 1 0.3 25.87 1 8.85 1 229.09 1 1.22 0.43 1 56.51 1 0.68 1.41 1 0 1 TRUE 1 0.81 671.69 1 675.09 1 OK -3.4 502B 1 1 671.69 1 30 1 25.87 1 78.9 1 0.4 % 1 0.31 1 8.85 1 0.3 1 22.04 1 14.28 1 314.76 1 3.17 1 1.11 1 58.29 1 1.n 1 3.19 1 0 1 TRUE 1 1.91 1 673.59 1 674 1 OK -0.41 5134 1 1 673.59 1 24 1 22.04 1 294.1 1 0.95% 1 2.79 1 14.28 1 0.79 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0.79 1 1.03 1 TRUE 1 3.31 1 676.9 1 684.52 1 OK -7.62 1S 2S 3S 4S Pre-DA1-West Pre-DA2-Southeast Pre-DA3-North Pre -DAM -Southeast - Undisturbed Subcat Reach on Link Routing Diagram for Pre -new Prepared by Timmons Group, Printed 8/4/2022 FHydroGAD(D 10.10-4a s/n 08663 © 2020 HydroCAD Software Solutions LLC Pre -new Prepared by Timmons Group Printed 8/4/2022 Project Notes Rainfall events imported from "NRCS-Rain.txt" for 8701 VA Albemarle Zone-1 Rainfall events imported from "NRCS-Rain.txt" for 8701 VA Albemarle Zone-1 Pre -new Prepared by Timmons Group Printed 8/4/2022 Rainfall Events Listing (selected events) Event# Event Storm Type Curve Mode Duration B/B Depth AMC Name (hours) (inches) 1 1-Year NOAA24-hr D Default 24.00 1 3.06 2 2 2-Year NOAA 24-hr D Default 24.00 1 3.70 2 3 10-Year NOAA 24-hr D Default 24.00 1 5.57 2 Pre -new Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Printed 8/4/2022 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentlS: Pre-DAl-West Runoff Area=1.059 ac 78.09% Impervious Runoff Depth>1.89" Tc=6.0 min CN=90 Runoff=2.41 cfs 0.167 of Subcatchment2S: Pre-DA2-Southeast Runoff Area=9.170 ac 28.90% Impervious Runoff Depth>0.89" Flow Length=1,568' Tc=11.7 min CN=75 Runoff=8.30 cfs 0.681 of Subcatchment3S: Pre-DA3-North Runoff Area=0.260 ac 61.54% Impervious Runoff Depth>1.97" Tc=6.0 min CN=91 Runoff=0.61 cfs 0.043 of Subcatchment4S: Pre-DA213-Southeast- Runoff Area=7.168 ac 29.92% Impervious Runoff Depth>1.16" Flow Length=1,214' Tc=22.0 min CN=80 Runoff=6.59 cfs 0.695 of Total Runoff Area = 17.657 ac Runoff Volume = 1.586 of Average Runoff Depth = 1.08" 67.25% Pervious = 11.875 ac 32.75% Impervious = 5.782 ac Pre -new NOAA 24-hrD 1-Year Rainfall=3.06" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 1S: Pre-DA1-West Runoff = 2.41 cfs @ 12.13 hrs, Volume= 0.167 af, Depth> 1.89" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 1-Year Rainfall=3.06" Area (ac) CN Description 0.192 98 Paved parking, HSG B 0.635 98 Paved parking, HSG D 0.202 61 >75% Grass cover, Good, HSG B 0.030 80 >75% Grass cover, Good, HSG D 1.059 90 Weighted Average 0.232 21.91 % Pervious Area 0.827 78.09% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Pre-DA1-West Hydrograph ❑ Runoff NOAA 24-hr D ----------------------7-- 1-Year Rainfall=3.06" z Runoff Area=1.059 ac Runoff Volume=0.167 of Runoff Depth>1.89" LL Tc=6.0 min CN=90 Time (hours) Pre -new NOAA 24-hr D 1-Year Rainfall=3.06" Timmons Summary for Subcatchment 2S: Pre-DA2-Southeast Runoff = 8.30 cfs @ 12.20 hrs, Volume= 0.681 af, Depth> 0.89" Printed 8/4/2022 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 1-Year Rainfall=3.06" Area (ac) CN Description 0.370 98 Paved parking, HSG B 2.280 98 Paved parking, HSG D 2.410 61 >75% Grass cover, Good, HSG B 1.660 80 >75% Grass cover, Good, HSG D 1.650 55 Woods, Good, HSG B 0.800 77 Woods, Good, HSG D 9.170 75 Weighted Average 6.520 71.10% Pervious Area 2.650 28.90% Impervious Area Tc Length Slope Velocity Capacity Description 1.0 100 0.0230 1.65 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.10" 0.8 197 0.0407 4.10 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.9 215 0.0560 3.81 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 5.8 403 0.0543 1.17 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 3.2 653 0.0200 3.41 27.59 Channel Flow, Area= 8.1 sf Perim= 11.1' r= 0.73' n= 0.050 11.7 1,568 Total Pre -new Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Subcatchment 2S: Pre-DA2-Southeast Hydrograph Printed 8/4/2022 9 ---------------i '---- ---- --------*--------i-------- i ' i i i i i i i ■Runoff , J�I --- --- -----i ----111 Lu pAth1�4I,0.h.8I'r 9D8 faHr-3.W"! % 1 1 =9.1I0 ac _ 6- - =0.6811af 5th 1;56W32 1 12 13 Time (hoes) Pre -new NOAA 24-hrD 1-Year Rainfall=3.06" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 3S: Pre-DA3-North Runoff = 0.61 cfs @ 12.13 hrs, Volume= 0.043 af, Depth> 1.97" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 1-Year Rainfall=3.06" Area (ac) CN Description 0.160 98 Paved parking, HSG D 0.100 80 >75% Grass cover, Good, HSG D 0.260 91 Weighted Average 0.100 38.46% Pervious Area 0.160 61.54% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, 101 Subcatchment 3S: Pre-DA3-North Hydrograph 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 I I I I I I I I I I I I I I I I I I I I I r I r-- I I I I . _J _L _J _L _J _L 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 r I I I I I I NOAA 24-hr D 1 -Year Rainfali=3.06" Runoff Area=0.260 ac Runoff Volume=0.043 of Runoff De'Ipth�-1.97" __ ___ & Arlin- ---- �----� �----�--- �----� I I I I _L 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 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) ■ Runoff Pre -new Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Printed 8/4/2022 Summary for Subcatchment 4S: Pre-DA2B-Southeast - Undisturbed Runoff = 6.59 cfs @ 12.33 hrs, Volume= 0.695 af, Depth> 1.16" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 1-Year Rainfall=3.06" Area (ac) CN Description 0.319 98 Paved parking, HSG B 1.826 98 Paved parking, HSG D 1.330 61 >75% Grass cover, Good, HSG B 2.869 80 >75% Grass cover, Good, HSG D 0.628 55 Woods, Good, HSG B 0.196 77 Woods, Good, HSG D 7.168 80 Weighted Average 5.023 70.08% Pervious Area 2.145 29.92% Impervious Area Tc Length Slope Velocity Capacity Description 16.1 100 0.0300 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 4.10" 0.7 122 0.0330 2.92 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.1 32 0.2180 7.52 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 1.7 378 0.0530 3.71 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 3.4 582 0.0370 2.83 11.04 Channel Flow, Area= 3.9 sf Perim= 11.2' r= 0.35' n= 0.050 22.0 1,214 Total Pre -new NOAA 24-hr D 1-Year Rainfall=3.06" Timmons Subcatchment 4S: Pre-DA213-Southeast - Undisturbed Hydrograph ---,----r ---- i____r---- ---,--- P Time (hours) Printed 8/4/2022 ---NNOAA 2.4-hr D- 1-Year kainfall-*.06" ---Runbff Areal=7.1-6&bc- Runoff', Vol',umq=0.',695', of Runoff Depth:�1.46" T16w-Len jth,1;214- Tc=22,0 rain Ff= 0 ❑ Runoff Pre -new Timmons NOAA 24-hr D 2-Year Rainfall=3.70" Printed 8/4/2022 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentlS: Pre-DAl-West Runoff Area=1.059 ac 78.09% Impervious Runoff Depth>2.45" Tc=6.0 min CN=90 Runoff=3.07 cfs 0.216 of Subcatchment2S: Pre-DA2-Southeast Runoff Area=9.170 ac 28.90% Impervious Runoff Depth>1.30" Flow Length=1,568' Tc=11.7 min CN=75 Runoff=12.29 cfs 0.993 of Subcatchment3S: Pre-DA3-North Runoff Area=0.260 ac 61.54% Impervious Runoff Depth>2.54" Tc=6.0 min CN=91 Runoff=0.77 cfs 0.055 of Subcatchment4S: Pre-DA213-Southeast- Runoff Area=7.168 ac 29.92% Impervious Runoff Depth>1.63" Flow Length=1,214' Tc=22.0 min CN=80 Runoff=9.26 cfs 0.972 of Total Runoff Area = 17.657 ac Runoff Volume = 2.236 of Average Runoff Depth = 1.52" 67.25% Pervious = 11.875 ac 32.75% Impervious = 5.782 ac Pre -new NOAA 24-hr D 2-Year Rainfall=3.70" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 1S: Pre-DA1-West Runoff = 3.07 cfs @ 12.13 hrs, Volume= 0.216 af, Depth> 2.45" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.70" Area (ac) CN Description 0.192 98 Paved parking, HSG B 0.635 98 Paved parking, HSG D 0.202 61 >75% Grass cover, Good, HSG B 0.030 80 >75% Grass cover, Good, HSG D 1.059 90 Weighted Average 0.232 21.91 % Pervious Area 0.827 78.09% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Pre-DA1-West Hydrograph ❑ Runoff 3 NOAA 24-hr D 2-Year Rainfall=3.70" Runoff Area=1.059 ac Runoff Volume=0.216 of z Runoff Depth>2.45" 0 LL Tc=6.0 min CN=90 Time (hours) Pre -new NOAA 24-hr D 2-Year Rainfall=3.70" Timmons Summary for Subcatchment 2S: Pre-DA2-Southeast Runoff = 12.29 cfs @ 12.20 hrs, Volume= 0.993 af, Depth> 1.30" Printed 8/4/2022 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.70" Area (ac) CN Description 0.370 98 Paved parking, HSG B 2.280 98 Paved parking, HSG D 2.410 61 >75% Grass cover, Good, HSG B 1.660 80 >75% Grass cover, Good, HSG D 1.650 55 Woods, Good, HSG B 0.800 77 Woods, Good, HSG D 9.170 75 Weighted Average 6.520 71.10% Pervious Area 2.650 28.90% Impervious Area Tc Length Slope Velocity Capacity Description 1.0 100 0.0230 1.65 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.10" 0.8 197 0.0407 4.10 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.9 215 0.0560 3.81 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 5.8 403 0.0543 1.17 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 3.2 653 0.0200 3.41 27.59 Channel Flow, Area= 8.1 sf Perim= 11.1' r= 0.73' n= 0.050 11.7 1,568 Total Pre -new Timmons NOAA 24-hr D 2-Year Rainfall=3.70" Subcatchment 2S: Pre-DA2-Southeast Hydrograph Printed 8/4/2022 i i i i ❑Runoff 13 1P 29� ,�4-h� D 12 „ ---2-Year kai-rtfallT3.7,0" 10RunOff AreA-9_170-'ac - 9 4 - -'-upoff'f�V-Oume=A-:,993;af - - a --------------r- --- ---RunoffDepth;pi1.30"- LL B Flow Lentf�,1,36$r- 5 , ---- ---J-- ------ ---- T-gL--- in a 3 ---------------- +_--- +---- 2r-. T Time (hours) Pre -new NOAA 24-hr D 2-Year Rainfall=3.70" Prepared by Timmons GrouD Printed 8/4/2022 Summary for Subcatchment 3S: Pre-DA3-North Runoff = 0.77 cfs @ 12.13 hrs, Volume= 0.055 af, Depth> 2.54" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.70" Area (ac) CN Description 0.160 98 Paved parking, HSG D 0.100 80 >75% Grass cover, Good, HSG D 0.260 91 Weighted Average 0.100 38.46% Pervious Area 0.160 61.54% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, 3 LL 0. 0. Subcatchment 3S: Pre-DA3-North I I I I NOAA ]]�� I I ----I--------`---NOAA 24A+_D I I ---2-Yeiar Rainfaflr-17 -'- ---Runbff_A-red=U26UTac ----I --------- I --------- I----♦--- .RiJFtOff Volbl mw=O:O5&af ----Runof(Depth�Z54" r_r---- I---- - T_t1 -=6,O iti N= 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 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (horns) ■ Runoff Pre -new Timmons NOAA 24-hr D 2-Year Rainfall=3.70" Printed 8/4/2022 Summary for Subcatchment 4S: Pre-DA2B-Southeast - Undisturbed Runoff = 9.26 cfs @ 12.32 hrs, Volume= 0.972 af, Depth> 1.63" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.70" Area (ac) CN Description 0.319 98 Paved parking, HSG B 1.826 98 Paved parking, HSG D 1.330 61 >75% Grass cover, Good, HSG B 2.869 80 >75% Grass cover, Good, HSG D 0.628 55 Woods, Good, HSG B 0.196 77 Woods, Good, HSG D 7.168 80 Weighted Average 5.023 70.08% Pervious Area 2.145 29.92% Impervious Area Tc Length Slope Velocity Capacity Description 16.1 100 0.0300 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 4.10" 0.7 122 0.0330 2.92 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.1 32 0.2180 7.52 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 1.7 378 0.0530 3.71 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 3.4 582 0.0370 2.83 11.04 Channel Flow, Area= 3.9 sf Perim= 11.2' r= 0.35' n= 0.050 22.0 1,214 Total Pre -new NOAA 24-hr D 2-Year Rainfall=3.70" Timmons Subcatchment 4S: Pre-DA213-Southeast - Undisturbed Hydrograph Printed 8/4/2022 - ----'----'- 10 i i i i i i i i ❑Runoff -Y -r -I -I -T h NOAA 2 -T 9 4-h� D RainfalCT3T0"-- ----Runoff AreA=t.46$ ac- ---------------- ----t-peff-V-OurnO=OA-72;a# - Runoff-Depthl-613"-- - 5 LL---;--------------�----�- � Flt�w_Len�th1,214'-- Tc=22': 0 ' in 3 tN='80 z 1 i Time (hours) Pre -new Timmons NOAA 24-hr D 10-Year Rainfall=5.57" Printed 8/4/2022 Time span=5.00-20.00 hrs, dt=0.05 hrs, 301 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentlS: Pre-DAl-West Runoff Area=1.059 ac 78.09% Impervious Runoff Depth>4.12" Tc=6.0 min CN=90 Runoff=5.00 cfs 0.364 of Subcatchment2S: Pre-DA2-Southeast Runoff Area=9.170 ac 28.90% Impervious Runoff Depth>2.67" Flow Length=1,568' Tc=11.7 min CN=75 Runoff=25.19 cfs 2.037 of Subcatchment3S: Pre-DA3-North Runoff Area=0.260 ac 61.54% Impervious Runoff Depth>4.22" Tc=6.0 min CN=91 Runoff=1.25 cfs 0.091 of Subcatchment4S: Pre-DA213-Southeast- Runoff Area=7.168 ac 29.92% Impervious Runoff Depth >3.11" Flow Length=1,214' Tc=22.0 min CN=80 Runoff=17.52 cfs 1.859 of Total Runoff Area = 17.657 ac Runoff Volume = 4.351 of Average Runoff Depth = 2.96" 67.25% Pervious = 11.875 ac 32.75% Impervious = 5.782 ac Pre -new NOAA 24-hr D 10-Year Rainfall=5.57" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 1S: Pre-DA1-West Runoff = 5.00 cfs @ 12.13 hrs, Volume= 0.364 af, Depth> 4.12" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.57" Area (ac) CN Description 0.192 98 Paved parking, HSG B 0.635 98 Paved parking, HSG D 0.202 61 >75% Grass cover, Good, HSG B 0.030 80 >75% Grass cover, Good, HSG D 1.059 90 Weighted Average 0.232 21.91 % Pervious Area 0.827 78.09% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Pre-DA1-West Hydrograph ❑ Runoff 5 NOAA 24-hr D 10-Year Rainfall=5.57" 4 Runoff Area=1.059 ac Runoff Volume=0.364 of 3I Runoff Depth>4.12" Tc=6.0 min 21 1 M � CN=90 12 13 14 15 16 17 18 19 20 Time (hours) Pre -new NOAA 24-hr D 10-Year Rainfall=5.57" Timmons Summary for Subcatchment 2S: Pre-DA2-Southeast Runoff = 25.19 cfs @ 12.20 hrs, Volume= 2.037 af, Depth> 2.67" Printed 8/4/2022 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.57" Area (ac) CN Description 0.370 98 Paved parking, HSG B 2.280 98 Paved parking, HSG D 2.410 61 >75% Grass cover, Good, HSG B 1.660 80 >75% Grass cover, Good, HSG D 1.650 55 Woods, Good, HSG B 0.800 77 Woods, Good, HSG D 9.170 75 Weighted Average 6.520 71.10% Pervious Area 2.650 28.90% Impervious Area Tc Length Slope Velocity Capacity Description 1.0 100 0.0230 1.65 Sheet Flow, Smooth surfaces n= 0.011 P2= 4.10" 0.8 197 0.0407 4.10 Shallow Concentrated Flow, Paved Kv= 20.3 fps 0.9 215 0.0560 3.81 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 5.8 403 0.0543 1.17 Shallow Concentrated Flow, Woodland Kv= 5.0 fps 3.2 653 0.0200 3.41 27.59 Channel Flow, Area= 8.1 sf Perim= 11.1' r= 0.73' n= 0.050 11.7 1,568 Total Pre -new NOAA 24-hr D 10-Year Rainfall=5.57" Prepared by Timmons Group Printed 8/4/2022 3 LL 5 6 7 Subcatchment 2S: Pre-DA2-Southeast Hydrograph 25. I I I I I I I I I I I I I I -r- ----- -------------i----'I----i---- ___14o0-:2 -tip f? I p Year Re. - ------------------I----a---- ---- Runbff Area=9.170 'ac Rupoff'1_V_oMumQ=2.'1,0V af- - Runoff Depth;>2.6�7"- -FldWLervOth* Y,56W-- ---r--- 7-eor=t TL'1*7-ra`in - �'Il---- IL ---- IL --- j----L ---- �L/ -i - Time (hours) 7 ■ Runoff Pre -new NOAA 24-hr D 10-Year Rainfall=5.57" Prepared by Timmons Group Printed 8/4/2022 LJ...1.. AM4n 4n I� ../.. nOGGO /l nnnn LJ...1.. Gll C..p........ C..L d:...... I !` rl--- nl Summary for Subcatchment 3S: Pre-DA3-North Runoff = 1.25 cfs @ 12.13 hrs, Volume= 0.091 af, Depth> 4.22" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.57" Area (ac) CN Description 0.160 98 Paved parking, HSG D 0.100 80 >75% Grass cover, Good, HSG D 0.260 91 Weighted Average 0.100 38.46% Pervious Area 0.160 61.54% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 3S: Pre-DA3-North Hydrograph ❑ Runoff 1 NOAA 24-hr D 10-Year Rainfall=5.57" Runoff Area=0.260 ac Runoff Volume=0.091 of Runoff Depth>4.22" Tc=6.0 min CN=91 0 — 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Time (hours) Pre -new Timmons NOAA 24-hr D 10-Year Rainfall=5.57" Printed 8/4/2022 Summary for Subcatchment 4S: Pre-DA2B-Southeast - Undisturbed [471 Hint: Peak is 159% of capacity of segment #5 Runoff = 17.52 cfs @ 12.32 hrs, Volume= 1.859 af, Depth> 3.11" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 5.00-20.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.57" Area (ac) CN Description 0.319 98 Paved parking, HSG B 1.826 98 Paved parking, HSG D 1.330 61 >75% Grass cover, Good, HSG B 2.869 80 >75% Grass cover, Good, HSG D 0.628 55 Woods, Good, HSG B 0.196 77 Woods. Good. HSG D 7.168 80 Weighted Average 5.023 70.08% Pervious Area 2.145 29.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 16.1 100 0.0300 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 4.10" 0.7 122 0.0330 2.92 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.1 32 0.2180 7.52 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 1.7 378 0.0530 3.71 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 3.4 582 0.0370 2.83 11.04 Channel Flow, Area= 3.9 sf Perim= 11.2' r= 0.35' n= 0.050 22.0 1,214 Total Pre -new NOAA 24-hr D 10-Year Rainfall=5.57" Timmons Subcatchment 4S: Pre-DA213-Southeast - Undisturbed Hydrograph I --------------- C -------------- -------------- 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 I I I I I I I I I I I I I I I I I I I I I I I -i -T -i Printed 8/4/2022 ---- -----I --- ---10=YearkainfallTs57' - -{ -r -y -r -I -* ---- Runbf#-Atrec-i=7.168ac - -T -r IRu4off.Yo�um�_=_1.18;:9,af _ ---- r _-TAL noff Depth;IAIW__ ----1-Fl w-Le"t/h�/ 1,21W - I T -r 1 I I -T - -- -I -T I -I - I I I Time (hours) ■ Runoff 1S 3S 4S 9S Post 1-West Post 2A-Sout ast Post B-Southeast post 2 Southeast Detained, Distu ed Detai ed, Undisturbed Undetai , Disturbed 6L Post -South ast 7P SWM 1OL Total SE Subcat Reach On Link Routing Diagram for Post -new Prepared by Timmons Group, Printed 8/4/2022 FHydroCAD@ 10.10-4a s/n 08663 02020 HydroCAD Software Solutions LLC Post -new Prepared by Timmons Group Printed 8/4/2022 Project Notes Rainfall events imported from "NRCS-Rain.txt" for 8701 VA Albemarle Zone-1 Post -new Prepared by Timmons Group Printed 8/4/2022 Rainfall Events Listing (selected events) Event# Event Storm Type Curve Mode Duration B/B Depth AMC Name (hours) (inches) 1 1-Year NOAA24-hr D Default 24.00 1 3.06 2 2 2-Year NOAA 24-hr D Default 24.00 1 3.70 2 3 10-Year NOAA 24-hr D Default 24.00 1 5.57 2 Post -new Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Printed 8/4/2022 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentlS: Post 1-West Runoff Area=0.280 ac 82.14% Impervious Runoff Depth>2.13" Tc=6.0 min CN=91 Runoff=0.66 cfs 0.050 of Subcatchment3S: Post 2A-Southeast Runoff Area=8.627 ac 35.61 % Impervious Runoff Depth>1.36" Flow Length=364' Tc=12.5 min CN=81 Runoff=10.74 cfs 0.974 of Subcatchment4S: Post 213-Southeast Runoff Area=7.168 ac 29.92% Impervious Runoff Depth>1.29" Flow Length=1,067' Tc=19.9 min CN=80 Runoff=6.93 cfs 0.769 of Subcatchment9S: Post 2C-Southeast Runoff Area=1.580 ac 23.42% Impervious Runoff Depth>1.05" Flow Length=1,420' Tc=11.6 min CN=76 Runoff=1.53 cfs 0.139 of Pond 7P: SWIM Peak Elev=668.37' Storage=10,786 cf Inflow=16.76 cfs 1.744 of Outflow=8.68 cfs 1.743 of Link 6L: Post -Southeast Inflow=16.76 cfs 1.744 of Primary=16.76 cfs 1.744 of Link 10L: Total SE Inflow=9.30 cfs 1.882 of Primary=9.30 cfs 1.882 of Total Runoff Area = 17.655 ac Runoff Volume = 1.932 of Average Runoff Depth = 1.31" 67.05% Pervious = 11.838 ac 32.95% Impervious = 5.817 ac Post -new NOAA 24-hr D 1-Year Rainfall=3.06" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 1S: Post 1-West Runoff = 0.66 cfs @ 12.13 hrs, Volume= 0.050 af, Depth> 2.13" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 1-Year Rainfall=3.06" Area (ac) CN Description 0.230 98 Paved parking, HSG B 0.050 61 >75% Grass cover, Good, HSG B 0.280 91 Weighted Average 0.050 17.86% Pervious Area 0.230 82.14% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Post 1-West ---r--T--r r 11--T--r--r- 0 7 0.65 i , MOAA 24-hr,D y _• _i _F I _� _� _i _F _I _I _♦ _i _i _I os ' 1-Year Rain=all3 1 r .06" r-�--T--r--r--r--r-i--r--r--r- 0.55 Runoff Area=0.280 ac Runoff Volume=0.050 of 0.45 0.4 Runoff Depth>2.13" c 0.35 v Tc=6.10 min-r--�-- 0.3 NCAI--li -----� G 0.25 0.2 i 0.15 r__r__r__i_____r__r__r_ 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 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (horns) ■ Runoff Post -new Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Printed 8/4/2022 Summary for Subcatchment 3S: Post 2A-Southeast Detained, Disturbed Runoff = 10.74 cfs @ 12.21 hrs, Volume= 0.974 af, Depth> 1.36" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 1-Year Rainfall=3.06" Area (ac) CN Description 1.221 98 Paved parking, HSG B 1.851 98 Paved parking, HSG D 2.384 61 >75% Grass cover, Good, HSG B 3.171 80 >75% Grass cover, Good, HSG D 8.627 81 Weighted Average 5.555 64.39% Pervious Area 3.072 35.61% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.5 100 0.0401 0.17 Sheet Flow, Grass: Dense n= 0.240 P2= 4.10" 1.0 188 0.0350 3.01 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.4 76 0.0260 3.27 Shallow Concentrated Flow, Paved Kv= 20.3 fps 1.6 Direct Entrv. Pioe Flow from Pipe Calcs 12.5 364 Total Subcatchment 3S: Post 2A-Southeast Detained, Disturbed Hydrograph 11NOAA 24-hr D 10 1-Year Rainfall=3.06" 9 Runoff Area=8.627 ac 8 Runoff Volume=0.974 of 7 Runoff Depth>1.36" 6 5 Flow Length=364' Tc=12.5 min 4 CN=81 I I I I I I F F i I I I I I I ■ RuneiF 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 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 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 I I I -------------------------- I I I I I I 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 Time (hours) Post -new Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Printed 8/4/2022 Summary for Subcatchment 4S: Post 2B-Southeast Detained, Undisturbed [471 Hint: Peak is 117% of capacity of segment #4 Runoff = 6.93 cfs @ 12.30 hrs, Volume= 0.769 af, Depth> 1.29" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 1-Year Rainfall=3.06" Area (ac) CN Description 0.319 98 1.826 98 1.330 61 >75% Grass cover, Good, HSG B 2.869 80 >75% Grass cover, Good, HSG D 0.628 55 Woods, Good, HSG B 0.196 77 Woods. Good. HSG D 7.168 80 Weighted Average 5.023 70.08% Pervious Area 2.145 29.92% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 16.1 100 0.0300 0.10 Sheet Flow, Woods: Light underbrush n= 0.400 P2= 4.10" 0.8 166 0.0480 3.53 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 2.4 627 0.0380 4.29 9.26 TrapNee/Rect Channel Flow, Bot.W=0.00' D=0.60' Z= 6.0'/' Top.W=7.20' n= 0.030 Earth, grassed & winding 0.6 174 0.0050 4.84 5.94 Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 19.9 1,067 Total Post -new Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Printed 8/4/2022 Subcatchment 4S: Post 213-Southeast Detained, Undisturbed Hydrograph i 0 AA 1-Yea �Aainf`a&106" _Ru iGfF Ard&M-l" bc'� Ru"oF VoMurno=0.769', of FlOW Lgngth,"_1,9f7'_ T&I%9', rain', ------- ------------------- ________________________________ -------------------------------- ------------------------ ---- -- --------- -- -- -- - -- --------- -- -- -- - ------ -- --------- -- -- -- - 4 5 6 7 8 9 10 11 12 13 Time (hours) ❑ Runoff Post -new NOAA 24-hr D 1-Year Rainfall=3.06" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 9S: Post 2C-Southeast Undetained, Disturbed Runoff = 1.53 cfs @ 12.20 hrs, Volume= 0.139 af, Depth> 1.05" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 1-Year Rainfall=3.06" Area (ac) CN Description 0.260 98 Paved parking, HSG B 0.110 98 Paved parking, HSG D 0.680 61 >75% Grass cover, Good, HSG B 0.530 80 >75% Grass cover, Good, HSG D 1.580 76 Weighted Average 1.210 76.58% Pervious Area 0.370 23.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.1 100 0.0746 0.33 Sheet Flow, Grass: Short n= 0.150 P2= 4.10" 3.3 667 0.0430 3.34 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 3.2 653 0.0200 3.41 27.59 Channel Flow, Area= 8.1 sf Perim= 11.1' r= 0.73' n= 0.050 11.6 1,420 Total Subcatchment 9S: Post 2C-Southeast Undetained, Disturbed ❑ Runoff NOAA 24-hr D 1-Year Rainfall=3.06" Runoff Area=1.580 ac Runoff Volume=0.139 of Runoff Depth>1.05" Flow Length=1,420' Tc=11.6 min CN=76 9 1 2 3 4 5 6 7 8 9 19 11 12 13 14 15 16 17 18 19 29 21 22 23 24 Time (hours) Post -new Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Summary for Pond 7P: SWM Printed 8/4/2022 Inflow Area = 15.795 ac, 33.03% Impervious, Inflow Depth > 1.32" for 1-Year event Inflow = 16.76 cfs @ 12.23 hrs, Volume= 1.744 of Outflow = 8.68 cfs @ 12.50 hrs, Volume= 1.743 af, Atten= 48%, Lag= 16.2 min Primary = 8.68 cfs @ 12.50 hrs, Volume= 1.743 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 668.37' @ 12.50 hrs Surf.Area= 3,612 sf Storage= 10,786 cf Plug -Flow detention time= 8.4 min calculated for 1.743 of (100% of inflow) Center -of -Mass det. time= 8.2 min ( 869.2 - 861.0 ) Volume Invert Avail.Storage Storage Description #1 664.00' 20,012 cf 84.0" Round Pipe Storagex 2 L= 260.0' S= 0.0050 T Device Routing Invert Outlet Devices #1 Primary 664.00' 24.0" Round Culvert L= 113.6' RCP, groove end projecting, Ke= 0.200 Inlet / Outlet Invert= 664.00' / 663.27' S= 0.0064 '/' Cc= 0.900 n= 0.013, Flow Area= 3.14 sf #2 Device 1 664.00' 13.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Device 1 668.50' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 0.50 1.50 2.50 Width (feet) 7.00 6.33 4.90 0.00 Primary OutFlow Max=8.68 cfs @ 12.50 hrs HW=668.36' (Free Discharge) t1=Culvert (Passes 8.68 cfs of 27.42 cfs potential flow) �2=Orifice/Grate (Orifice Controls 8.68 cfs @ 9.41 fps) 3=Custom Weir/Orifice ( Controls 0.00 cfs) Post -new Timmons Pond 7P: SWM Hydrograph NOAA 24-hr D 1-Year Rainfall=3.06" Printed 8/4/2022 1__L__L_J__ 18.]8 cra I I I I I I I I I I I -1in�ro�_v_M00'=fl5i795=a� -L I J L-J J--L--L--L-J I I I I I I I I I I I , 8toragiez4161, 186-6 _--'-- -- - -- --'-- -- _ , _1 _L _L 968 cfs I L__I__J__1__L__I__J__y__L__L__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 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 4 5 6 7 8 9 10 11 12 13 Time (hours) ■ Inflow ■ Primary Post -new NOAA 24-hr D 1-Year Rainfall=3.06" Prepared by Timmons Group Printed 8/4/2022 Summary for Link 6L: Post -Southeast Inflow Area = 15.795 ac, 33.03% Impervious, Inflow Depth > 1.32" for 1-Year event Inflow = 16.76 cfs @ 12.23 hrs, Volume= 1.744 of Primary = 16.76 cfs @ 12.23 hrs, Volume= 1.744 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link 6L: Post -Southeast Hydrograph ❑ Inflow - L----J--J--L---J--L- -L--L -J -- 0Pr1ma ry L IIII 1LL_ 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 I I I I I I I I I I I I I I 1 1 I +__L__L__I__ I 1 1 I I I 1 I I I I I I { 1 I 1 I I I I I I I I I I 8 9 10 11 12 13 Time (hours) Post -new Prepared by Timmons NOAA 24-hr D 1-Year Rainfall=3.06" Printed 8/4/2022 LLC Page 13 Summary for Link 10L: Total SE Inflow Area = 17.375 ac, 32.16% Impervious, Inflow Depth > 1.30" for 1-Year event Inflow = 9.30 cfs @ 12.44 hrs, Volume= 1.882 of Primary = 9.30 cfs @ 12.44 hrs, Volume= 1.882 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link 10L: Total SE Hydrograph ❑ I nflow [I Primary r--r-r r__r_ 1__r__i r 1 1 ---- _______ i I I i I I ---- 1 1 __________---- i i I i i I I I 1 i 1 i i I I 1 i i I 1 I 1 1 i 1 J.__L_J__J__1__L__L_J. I I i i I _Y I 1 _Y I i _ 1I 11 12 13 14 15 16 Time (hours) Post -new Timmons NOAA 24-hr D 2-Year Rainfall=3.70" Printed 8/4/2022 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentlS: Post 1-West Runoff Area=0.280 ac 82.14% Impervious Runoff Depth>2.73" Tc=6.0 min CN=91 Runoff=0.83 cfs 0.064 of Subcatchment3S: Post 2A-Southeast Runoff Area=8.627 ac 35.61 % Impervious Runoff Depth>1.87" Flow Length=364' Tc=12.5 min CN=81 Runoff=14.86 cfs 1.342 of Subcatchment4S: Post 213-Southeast Runoff Area=7.168 ac 29.92% Impervious Runoff Depth>1.79" Flow Length=1,067' Tc=19.9 min CN=80 Runoff=9.71 cfs 1.068 of Subcatchment9S: Post 2C-Southeast Runoff Area=1.580 ac 23.42% Impervious Runoff Depth>1.51" Flow Length=1,420' Tc=11.6 min CN=76 Runoff=2.23 cfs 0.198 of Pond 7P: SWIM Peak Elev=669.08' Storage=13,337 cf Inflow=23.34 cfs 2.409 of Outflow=19.18 cfs 2.408 of Link 6L: Post -Southeast Inflow=23.34 cfs 2.409 of Primary=23.34 cfs 2.409 of Link 10L: Total SE Inflow=20.48 cfs 2.607 of Primary=20.48 cfs 2.607 of Total Runoff Area = 17.655 ac Runoff Volume = 2.671 of Average Runoff Depth = 1.82" 67.05% Pervious = 11.838 ac 32.95% Impervious = 5.817 ac Post -new NOAA 24-hr D 2-Year Rainfall=3.70" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 1S: Post 1-West Runoff = 0.83 cfs @ 12.13 hrs, Volume= 0.064 af, Depth> 2.73" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.70" Area (ac) CN Description 0.230 98 Paved parking, HSG B 0.050 61 >75% Grass cover, Good, HSG B 0.280 91 Weighted Average 0.050 17.86% Pervious Area 0.230 82.14% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Post 1-West .1 _1 _1 .1 O,py,jy I 1 0.85 I _ 1 1--�--�--1----I—J--1--1--L--1-- '--J --L-- L - -I -- 0.8 - a ► = �----=--=--=--'I ---- -- ------------- -- - I 1 1 I I I 1 1 I I I I I I I I I I I I I I 0.75 ,III -2-bear-RainflaN=170",--I---11--;--;-----I- --I--;--;-----I- --I- - 0 7- _ L /I _��LL I _JJJ r_ I yyy , Lr,__7__r__r__r__I__,__rr ____r_ RM" V {a rI—u v p__------,--r--rrI------ 0.55 V 0.5 '-Runoff Depth>,2.73"--- 'I I I I I I I I I I O 045 0.4 ' 1 1 c= .���_I+__I__+I__i__+ LL T� 1 1 •--91_L _L _I _I _J -1 -L _I 1 0.3 --I-- 1--J--1--L--`--I--`--J--1--1--J--1--L--`--I-- '--J--1--L--1-- 1 1 1 1 1 1 1 0.25 I1 ' --I-- 1--J----L--L--I--J0.2 --J--1---J--1--1--L--1-- '--J--L--L--I-- 1 1 1 1 1 1 1 1 I I I 1 I I I 1 1 1 I 1 1 I I I 1 1 I I I 0.15 I I I 1 I I I 1 1 1 I 1 1 I I I 1 1 1 I I 0 1 1 I I I 1 I I I I 1 1 I I I I 1 1 I I I 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (horns) ■ Runoff Post -new Timmons NOAA 24-hr D 2-Year Rainfall=3.70" Printed 8/4/2022 Summary for Subcatchment 3S: Post 2A-Southeast Detained, Disturbed Runoff = 14.86 cfs @ 12.21 hrs, Volume= 1.342 af, Depth> 1.87" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.70" Area (ac) CN Description 1.221 98 Paved parking, HSG B 1.851 98 Paved parking, HSG D 2.384 61 >75% Grass cover, Good, HSG B 3.171 80 >75% Grass cover, Good, HSG D 8.627 81 Weighted Average 5.555 64.39% Pervious Area 3.072 35.61% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.5 100 0.0401 0.17 Sheet Flow, Grass: Dense n= 0.240 P2= 4.10" 1.0 188 0.0350 3.01 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.4 76 0.0260 3.27 Shallow Concentrated Flow, Paved Kv= 20.3 fps 1.6 Direct Entrv. Pioe Flow from Pipe Calcs 12.5 364 Total Subcatchment 3S: Post 2A-Southeast Detained, Disturbed Hydrograph 15 NOAA 24-hr D---I--r 14 13 2-Year Rainfall=3.70" 12 Runoff Area=8.627 ac 11 Runoff Volume=1.342 of 10 9 Runoff Depth>1.87" 8 Flow Length=364' 6 Tc=12.5 min 5 C p 4 3 I I I I I I I I I I I I 2 1 L__L__L _I _L _1__L _L ' ' ' ' ❑Runoff �--�--T--r--r-- 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 r - I I- I- I r 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 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 I I I I I I I r__r__r__�__T__r__r__r__r__ I I I I I I I I I I 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Post -new NOAA 24-hr D 2-Year Rainfall=3.70" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 4S: Post 2B-Southeast Detained, Undisturbed [471 Hint: Peak is 105% of capacity of segment #3 [471 Hint: Peak is 163% of capacity of segment #4 Runoff = 9.71 cfs @ 12.30 hrs, Volume= 1.068 af, Depth> 1.79" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.70" Area (ac) CN Description 0.319 98 1.826 98 1.330 61 >75% Grass cover, Good, HSG B 2.869 80 >75% Grass cover, Good, HSG D 0.628 55 Woods, Good, HSG B 0.196 77 Woods, Good, HSG D 7.168 80 Weighted Average 5.023 70.08% Pervious Area 2.145 29.92% Impervious Area Tc min) Length (feet) Slope (ft/ft) Velocity (ft/sec) 16.1 100 0.0300 0.10 Capacity Description 0.8 166 0.0480 3.53 2.4 627 0.0380 4.29 9.26 0.6 174 0.0050 4.84 5.94 19.9 1,067 Total Sheet Flow, Woods: Light underbrush n= 0.400 P2= 4.10" Shallow Concentrated Flow, Unpaved Kv= 16.1 fps TrapNee/Rect Channel Flow, Bot.W=0.00' D=0.60' Z= 6.0'/' Top.W=7.20' n= 0.030 Earth, grassed & winding Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 Post -new Timmons NOAA 24-hr D 2-Year Rainfall=3.70" Printed 8/4/2022 Subcatchment 4S: Post 213-Southeast Detained, Undisturbed Hydrograph -NOAA 2*4r, _ 2 bear _iainfallr3.70" _Ruhaff-Arda=I�168_cic:-- Ru_ goy o�urnQ:F 8', of Ikunoff IJe�„Itfi>1.f9'! Wv Le'nOW 067 to - L I' - 7c=1$.9', rril. G`N=80 4 5 6 7 8 9 10 11 12 13 Time (hours) 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 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 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 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 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 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 J--' - - - -- ■ Runoff Post -new NOAA 24-hr D 2-Year Rainfall=3.70" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 9S: Post 2C-Southeast Undetained, Disturbed Runoff = 2.23 cfs @ 12.20 hrs, Volume= 0.198 af, Depth> 1.51" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 2-Year Rainfall=3.70" Area (ac) CN Description 0.260 98 Paved parking, HSG B 0.110 98 Paved parking, HSG D 0.680 61 >75% Grass cover, Good, HSG B 0.530 80 >75% Grass cover, Good, HSG D 1.580 76 Weighted Average 1.210 76.58% Pervious Area 0.370 23.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.1 100 0.0746 0.33 Sheet Flow, Grass: Short n= 0.150 P2= 4.10" 3.3 667 0.0430 3.34 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 3.2 653 0.0200 3.41 27.59 Channel Flow, Area= 8.1 sf Perim= 11.1' r= 0.73' n= 0.050 11.6 1,420 Total Subcatchment 9S: Post 2C-Southeast Undetained, Disturbed ❑ Runoff NOAA 24-hr D 2 2-Year Rainfall=3.70" Runoff Area=1.580 ac Runoff Volume=0.198 of Runoff Depth>1.51" Flow Length=1,420' Tc=11.6 min CN=76 9 1 2 3 4 5 6 7 8 9 19 11 12 13 14 15 16 17 18 19 29 21 22 23 24 Time (hours) Post -new Timmons NOAA 24-hr D 2-Year Rainfall=3.70" Summary for Pond 7P: SWM Printed 8/4/2022 Inflow Area = 15.795 ac, 33.03% Impervious, Inflow Depth > 1.83" for 2-Year event Inflow = 23.34 cfs @ 12.23 hrs, Volume= 2.409 of Outflow = 19.18 cfs @ 12.36 hrs, Volume= 2.408 af, Atten= 18%, Lag= 7.5 min Primary = 19.18 cfs @ 12.36 hrs, Volume= 2.408 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 669.08' @ 12.36 hrs Surf.Area= 3,485 sf Storage= 13,337 cf Plug -Flow detention time= 8.8 min calculated for 2.403 of (100% of inflow) Center -of -Mass det. time= 8.6 min ( 859.4 - 850.8 ) Volume Invert Avail.Storage Storage Description #1 664.00' 20,012 cf 84.0" Round Pipe Storagex 2 L= 260.0' S= 0.0050 T Device Routing Invert Outlet Devices #1 Primary 664.00' 24.0" Round Culvert L= 113.6' RCP, groove end projecting, Ke= 0.200 Inlet / Outlet Invert= 664.00' / 663.27' S= 0.0064 '/' Cc= 0.900 n= 0.013, Flow Area= 3.14 sf #2 Device 1 664.00' 13.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Device 1 668.50' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 0.50 1.50 2.50 Width (feet) 7.00 6.33 4.90 0.00 Primary OutFlow Max=18.97 cfs @ 12.36 hrs HW=669.07' (Free Discharge) t1=Culvert (Passes 18.97 cfs of 30.40 cfs potential flow) �2=Orifice/Grate (Orifice Controls 9.45 cfs @ 10.25 fps) 3=Custom Weir/Orifice (Weir Controls 9.52 cfs @ 2.51 fps) Post -new NOAA 24-hr D 2-Year Rainfall=3.70" Prepared by Timmons Group Printed 8/4/2022 Pond 7P: SWM Hydrograph 1 Inflow 26 __1___1__rI 1 21,MLLMaryj 1�oAI'e�--I .7"24-rT-r_T-r_r�ea e�_r_ _J _1 _L �- 18- I I I I I "atd - 11 III III , 11111111 1111111111 1 1 1 1 1 1 1 1 I I I I I I I I I I 16- .@ 14--1----+--r--1---1--+--r--1---- ---1----t--r--1----+--r--r--1-- - I I I I I I I I I I I 3 1 1 12 LL I I i i i I I I I I I , 1 1 1 1 1 10 , 1 1 I I I I I I I I I I I I , 1 I I I 1 1 I I 1 1 1 1 1 1 --L--L--L--1----L--L--1-- 6- 4- 4 5 6 7 8 9 10 11 12 13 Time (hours) Post -new Prepared by Timmons NOAA 24-hr D 2-Year Rainfall=3.70" Printed 8/4/2022 i n--- nn Summary for Link 6L: Post -Southeast Inflow Area = 15.795 ac, 33.03% Impervious, Inflow Depth > 1.83" for 2-Year event Inflow = 23.34 cfs @ 12.23 hrs, Volume= 2.409 of Primary = 23.34 cfs @ 12.23 hrs, Volume= 2.409 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link 6L: Post -Southeast Hydrograph ' ❑ Inflow 26 _____ za as cra I I I I I I I ❑Primary 24 I _r__� _r__r__r_I__r__r__r__�. Inflow Area=!I51.795, 23M ft 20 ____�__�__L. ._i__L__ _ L__�__ J__ i__ L_ �__J__ 1__ L__ L_!. 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 16- I I I I I i I I I I I I IF 14- i I I I i i I I i I I I i i I I I i ii 12 LL I I I I I I I I I I I 10 , __r _T__T__r__� 6 �_- 2 Time (hours) Post -new NOAA 24-hr D 2-Year Rainfall=3.70" Prepared by Timmons Group Printed 8/4/2022 Summary for Link 10L: Total SE Inflow Area = 17.375 ac, 32.16% Impervious, Inflow Depth > 1.80" for 2-Year event Inflow = 20.48 cfs @ 12.35 hrs, Volume= 2.607 of Primary = 20.48 cfs @ 12.35 hrs, Volume= 2.607 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link 10L: Total SE Hydrograph ❑Inflow ,I ❑ Primary cra 1� IF I~ _T _I___I__ T _r 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 r I I I I I T__r__I__,__T__r__r__I__ I -F -F y _T _1 _I _1 _T 1 _r _r _I I I I I I I I I I 1 r 1 - r--r-------T--r--r--- 1 Time (hours) Post -new Timmons NOAA 24-hr D 10-Year Rainfall=5.57" Printed 8/4/2022 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS, Weighted-CN Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentlS: Post 1-West Runoff Area=0.280 ac 82.14% Impervious Runoff Depth>4.53" Tc=6.0 min CN=91 Runoff=1.34 cfs 0.106 of Subcatchment3S: Post 2A-Southeast Runoff Area=8.627 ac 35.61 % Impervious Runoff Depth>3.48" Flow Length=364' Tc=12.5 min CN=81 Runoff=27.55 cfs 2.505 of Subcatchment4S: Post 213-Southeast Runoff Area=7.168 ac 29.92% Impervious Runoff Depth>3.38" Flow Length=1,067' Tc=19.9 min CN=80 Runoff=18.35 cfs 2.019 of Subcatchment9S: Post 2C-Southeast Runoff Area=1.580 ac 23.42% Impervious Runoff Depth>3.00" Flow Length=1,420' Tc=11.6 min CN=76 Runoff=4.49 cfs 0.396 of Pond 7P: SWM Peak Elev=670.88' Storage=18,720 cf Inflow=43.71 cfs 4.524 of Outflow=36.92 cfs 4.522 of Link 6L: Post -Southeast Inflow=43.71 cfs 4.524 of Primary=43.71 cfs 4.524 of Link 10L: Total SE Inflow=39.98 cfs 4.918 of Primary=39.98 cfs 4.918 of Total Runoff Area = 17.655 ac Runoff Volume = 5.026 of Average Runoff Depth = 3.42" 67.05% Pervious = 11.838 ac 32.95% Impervious = 5.817 ac Post -new NOAA 24-hr D 10-Year Rainfall=5.57" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 1S: Post 1-West Runoff = 1.34 cfs @ 12.13 hrs, Volume= 0.106 af, Depth> 4.53" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.57" Area (ac) CN Description 0.230 98 Paved parking, HSG B 0.050 61 >75% Grass cover, Good, HSG B 0.280 91 Weighted Average 0.050 17.86% Pervious Area 0.230 82.14% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment 1S: Post 1-West ❑ Runoff i NOAA 24-hr'D 10-Year Rainfall=5.57 Runoff Area=0.280 ac Runoff Volume=0.106 of Runoff Depth>4.53" Tc=6.0 min CN=91 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (horns) Post -new Timmons NOAA 24-hr D 10-Year Rainfall=5.57" Printed 8/4/2022 Summary for Subcatchment 3S: Post 2A-Southeast Detained, Disturbed Runoff = 27.55 cfs @ 12.20 hrs, Volume= 2.505 af, Depth> 3.48" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.57" Area (ac) CN Description 1.221 98 Paved parking, HSG B 1.851 98 Paved parking, HSG D 2.384 61 >75% Grass cover, Good, HSG B 3.171 80 >75% Grass cover, Good, HSG D 8.627 81 Weighted Average 5.555 64.39% Pervious Area 3.072 35.61% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 9.5 100 0.0401 0.17 Sheet Flow, Grass: Dense n= 0.240 P2= 4.10" 1.0 188 0.0350 3.01 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 0.4 76 0.0260 3.27 Shallow Concentrated Flow, Paved Kv= 20.3 fps 1.6 Direct Entrv. Pioe Flow from Pipe Calcs 12.5 364 Total Subcatchment 3S: Post 2A-Southeast Detained, Disturbed Hydrograph NOAA 24-hr D 10-Year Rainfall=5.57" Runoff Area=8.627 ac Runoff Volume=2.505,af- Runoff Depth>3.487 -- Flow Length=3W__'___'__ Tc=12.5 min ---; - CN=81- I IF I I I I I I I I I I I I I I I I I I �r ■ Runoff 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 I I I I I I I I I I I I I I I I I I I I I I___I _II __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 I I I I I I I I I 1 I I 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Post -new NOAA 24-hr D 10-Year Rainfall=5.57" Prepared by Timmons Group Printed 8/4/2022 Summary for Subcatchment 4S: Post 2B-Southeast Detained, Undisturbed [471 Hint: Peak is 198% of capacity of segment #3 [471 Hint: Peak is 309% of capacity of segment #4 Runoff = 18.35 cfs @ 12.29 hrs, Volume= 2.019 af, Depth> 3.38" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.57" Area (ac) CN Description 0.319 98 1.826 98 1.330 61 >75% Grass cover, Good, HSG B 2.869 80 >75% Grass cover, Good, HSG D 0.628 55 Woods, Good, HSG B 0.196 77 Woods, Good, HSG D 7.168 80 Weighted Average 5.023 70.08% Pervious Area 2.145 29.92% Impervious Area Tc min) Length (feet) Slope (ft/ft) Velocity (ft/sec) 16.1 100 0.0300 0.10 Capacity Description 0.8 166 0.0480 3.53 2.4 627 0.0380 4.29 9.26 0.6 174 0.0050 4.84 5.94 19.9 1,067 Total Sheet Flow, Woods: Light underbrush n= 0.400 P2= 4.10" Shallow Concentrated Flow, Unpaved Kv= 16.1 fps TrapNee/Rect Channel Flow, Bot.W=0.00' D=0.60' Z= 6.0'/' Top.W=7.20' n= 0.030 Earth, grassed & winding Pipe Channel, 15.0" Round Area= 1.2 sf Perim= 3.9' r= 0.31' n= 0.010 Post -new Timmons NOAA 24-hr D 10-Year Rainfall=5.57" Printed 8/4/2022 Subcatchment 4S: Post 213-Southeast Detained, Undisturbed Hydrograph 20 ---T---,-----*--I --,I --rI --I--,I --,-----T ---T,----r,I un ----1r---,�----,,----TT----rr----rr--- ----rrI i-r --r--I -I--T - 19 18 I I I I I I I I I I I -•'OI I 1• I--I_-1_-______ 17 - �//��R�Afah=&S 'g- 16 ----i--L----'�----J--'--i--i--�-- -�S��I��-{{Lh� 15 -RU1iVfr Arl 14 13 12 All r 1 1 1 1 1 1 1 1 1 to a ff _opt, 10 a 9 1 -- 1 I I 1 1 1 I I I I 1 1 f 1 __1_ 1 ,Mini-- --'--'---' --i--'-------J--i-- -- -- -- 6 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 4 1 31 ' 1 1 1 1 1 1 1 1 1 1 21 I --- �--i__i 4 5 6 7 8 9 10 11 12 13 Time (hours) Post -new Timmons NOAA 24-hr D 10-Year Rainfall=5.57" Printed 8/4/2022 Summary for Subcatchment 9S: Post 2C-Southeast Undetained, Disturbed Runoff = 4.49 cfs @ 12.20 hrs, Volume= 0.396 af, Depth> 3.00" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs NOAA 24-hr D 10-Year Rainfall=5.57" Area (ac) CN Description 0.260 98 Paved parking, HSG B 0.110 98 Paved parking, HSG D 0.680 61 >75% Grass cover, Good, HSG B 0.530 80 >75% Grass cover, Good, HSG D 1.580 76 Weighted Average 1.210 76.58% Pervious Area 0.370 23.42% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.1 100 0.0746 0.33 Sheet Flow, Grass: Short n= 0.150 P2= 4.10" 3.3 667 0.0430 3.34 Shallow Concentrated Flow, Unpaved Kv= 16.1 fps 3.2 653 0.0200 3.41 27.59 Channel Flow, Area= 8.1 sf Perim= 11.1' r= 0.73' n= 0.050 11.6 1,420 Total Subcatchment 9S: Post 2C-Southeast Undetained, Disturbed i i 4A9 cfa NOAA 24-hr D 4 10-Year Rainfall=5.57" Runoff Area=1.580 ac 3 Runoff Volume=0.396 of Runoff Depth>3.00" Flow Length=1,420' 2 Tc=11.6 min CN=76 9 1 2 3 4 5 6 7 8 9 19 11 12 13 14 15 16 17 18 19 29 21 22 23 24 Time (hours) Post -new Timmons NOAA 24-hr D 10-Year Rainfall=5.57" Summary for Pond 7P: SWM Printed 8/4/2022 Inflow Area = 15.795 ac, 33.03% Impervious, Inflow Depth > 3.44" for 10-Year event Inflow = 43.71 cfs @ 12.23 hrs, Volume= 4.524 of Outflow = 36.92 cfs @ 12.32 hrs, Volume= 4.522 af, Atten= 16%, Lag= 5.9 min Primary = 36.92 cfs @ 12.32 hrs, Volume= 4.522 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 670.88' @ 12.32 hrs Surf.Area= 2,178 sf Storage= 18,720 cf Plug -Flow detention time= 8.5 min calculated for 4.522 of (100% of inflow) Center -of -Mass det. time= 8.2 min ( 839.3 - 831.0 ) Volume Invert Avail.Storage Storage Description #1 664.00' 20,012 cf 84.0" Round Pipe Storagex 2 L= 260.0' S= 0.0050 T Device Routing Invert Outlet Devices #1 Primary 664.00' 24.0" Round Culvert L= 113.6' RCP, groove end projecting, Ke= 0.200 Inlet / Outlet Invert= 664.00' / 663.27' S= 0.0064 '/' Cc= 0.900 n= 0.013, Flow Area= 3.14 sf #2 Device 1 664.00' 13.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Device 1 668.50' Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet) 0.00 0.50 1.50 2.50 Width (feet) 7.00 6.33 4.90 0.00 Primary OutFlow Max=36.77 cfs @ 12.32 hrs HW=670.83' (Free Discharge) t1=Culvert (Barrel Controls 36.77 cfs @ 11.70 fps) �2=Orifice/Grate (Passes < 11.13 cfs potential flow) 3=Custom Weir/Orifice (Passes < 63.68 cfs potential flow) Post -new 42 40 38 36 34 32 30 26 2 24 ° 22 u 20 18 16 Timmons Pond 7P: SWM Hydrograph NOAA 24-hr D 10-Year Rainfall=5.57" Printed 8/4/2022 ---- -------------- '--`-------- ------'-----'--`--' I _ -- __/u,�.�l _I1 __I__ -_ II __Ir _ - �__ �I __Ir Ir _ - M{jr j�I I I I I I I I I I I I _J _y}^F.�p_I\� _I _I I I I I I _I _J _y _F _I _y _y _F _F _I /R�_i%■/��_J/x�_I 3692 T--r_ I- - - - - T- -r - -r_ i-- - -I 1 1 1 4__r__I__�_- 1 1 1 _1__L _I _J _J _L _I _J__ ___I__J__1__L _I _J _1 _L _L_J__ 1 1 1 1 1 I 1 _ I Y _I _I _Y__Y__I _�__ I I __ I__T__T__r _I _y J__ L__L__I__ JJ__ L_ J_I_ J- I I -___ J__ L__ L_ J_I_ JI__ L__ L__ L_J__ I__ I __I__y__}__Y__I___I__Y__Y__I__y_- I I -__I__y__}__Y__I__y__}__Y__r__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 I I I I I 4 5 Time (hours) ■ Inflow ■ Primary Post -new NOAA 24-hr D 10-Year Rainfall=5.57" Prepared by Timmons Group Printed 8/4/2022 Summary for Link 6L: Post -Southeast Inflow Area = 15.795 ac, 33.03% Impervious, Inflow Depth > 3.44" for 10-Year event Inflow = 43.71 cfs @ 12.23 hrs, Volume= 4.524 of Primary = 43.71 cfs @ 12.23 hrs, Volume= 4.524 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link 6L: Post -Southeast Hydrograph 44 Inflow Area=1-5,795,q 42 - ___+__�____ - 40 1r--r- 38 -- 36 __i__,__ 1__r__�___�__�__r__r___ 34 i ' I 32 , __r_r__r__r__� 30 � 28 V 26. 1__L__I__ 24 O 22 _ _1LIJ__1L__L_J_ LL ZO 1816 14 I I 10 8 y 1 1 - ■ Primary 1 1 _r_r__r__r__r__I__r__r__r__r_ 1 1 1 1 1 1 1 1 I I 1 I 1 1 1 I I -r-i-T--T--r--I--�--T--r-r-I-- 1 1 1 I _L__I__J__1__L_ I__J__1__L__L_ I I _r _I _1 _T _r _I _1 I I I I I I I I I I I L_J__ J__ 1__ L_J__J__ I 1__ L__ L_J__ I I I I I I I__ I I I I 1 1 I I 1 1 I I 1 1 I 1 I Time (hours) Post -new NOAA 24-hr D 10-Year Rainfall=5.57" Prepared by Timmons Group Printed 8/4/2022 Summary for Link 10L: Total SE Inflow Area = 17.375 ac, 32.16% Impervious, Inflow Depth > 3.40" for 10-Year event Inflow = 39.98 cfs @ 12.29 hrs, Volume= 4.918 of Primary = 39.98 cfs @ 12.29 hrs, Volume= 4.918 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs 44 42 40 38 36 34 32 30 28 26 24 22 LL 20 18 16 14 12 10 8 6 4 2 6 0 Link 10L: Total SE Hydrograph Inflow Area=17.37 I I I I I I I I I I I I I I J__1__L__I__J__1__L__I__J. I I I I I I I I I I I I I I I I I I I I J__L__L I I I I I I I I I I I I I I I I I I I I ------- --- ❑Inflow [I Primary _L__IJI--L---J--L--L--L_J-_ IIIIIIIIIII 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 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 I I I I I I I I I I I I I I I -l--T--r--I--1--T--r--r--I-- I I I I I I I I I I I I I I I I I I I I 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Time (hours) If ' �� 1. ' • iIl III111 I b 1 1 IIINI � iii�INIIiNN�I� ; I�'Ir �' IN � h I Ifa 1 A 1 I 1 •a ••I I III ;• 11 I�iiNNINNIII�� 11��� ,��N` ,� _II° :, - . � -�, -�i ••:I pp!Im .•�I -;� �iN iiii�ll;�,illl��l' III IHIIIIIII •1 I �I��� Ir 1'I I I , / I 11I 1141 II 11IIIIIIIIIIN 11111 I1�� li ��;, � ,�� •��I. ;III ,�iiINIII!�IIIII ��i��91����l;Illlhillllll!ill�l'I ��ilp lll;, lllllll 11 I i , � Ill II. fill ill Illl H� �1�11pppppp Io I i Il i I l�n rl a u n mono IIII�IIIIIO NI I'I+111 /�:I Nli• II • C° 11� ! 1!�I�11�1���!II'�'!���„'y1�I��1; ll nll IIIIIIIIIIIIII�IIIIII!IIII: �!iI�tdIINl��i!iN /Iglu;�l � il, III �I�llllMi11 �ItlY IIIIIII IIII111111 !;i;l�llllllllllil. � �.� � r iilNuii ilill�IIIIIIIIINNN.'lil r ff I N .11� � '1� i. IIIIIIilllllllllll II�IIIII III ' r 1 r IAII I • +I C' II 1tll l' IIIIIIIIIIIIIIIIIIIII/1..1ffIIIIIIIIII In,i I I I 11 I' 1 . I!I,!' I IIIl llllllllnlllllll,Silll.11l1Illlll'i II = a �' li 11 � _,. I „�.1'1 lI1P�. P F ! l�aln�n II IIIIIIIIIIIIIIIIII:111 1111 IIIIIGI'I I �� 9 !� ! II I { ry pI �'.1 1pp 11lffHIM 11m:1l1I1 Ill O ICII 'IIl��ll •.'I�IN IIII�IIIIIIIIIIfillllll�lll��!IIIiIIIIIIIgII�I����.���9��1h lllllll IIIRI I111111111 1!' I I I r � I — Po IIIIIIII; � II 1 1 1 11 11 11 111 1 In 0 0 a cn :. 1 1 1 1 I • d° : 1 • AIlq 1 I I �fll I„Itj"II • 1 I tttlllllll i!�a�lru.: ll���J _:RII • �A .�..�.� 1 , • 1 Illllglll� I`�I t •' I I!� ,�1 Ir �����r •� M ill � �'• ! Hill" � I I .� ►��r � I ��,, Iryrymlaw l! IIii�l Ui1N.itil I `'iill.nl i 1 II 1 III I ■ 1 i"�j�In' 1+j I v l Imml ry� ryUI1Ipp I1mp Il IIII 1 iilii ,tl" �ry. I I Ii1�j I�I p1'NtIII!1''i��ll 'iI Ij 1ij IIII ■ � ! n•"ni 111 l " I' ��I�III�I�I'll�l i l I pp/1 I'I I• IH;IIIN 1 1� IryI 11jryi/1 III IIIIIIII I!I IIIA I'lll 1 '•ililiiliiHlll!�i11�11'i1M11111111 IIII II IIIII IIIII IIIII 1 11 , l Mit 1 uryIIIIII 111 IIIII IIII IIII Illy II III R::..=11i• 11:'"III"'I'pry� �p�1,�IIp1yI'I IIIIIIIIII�IIIIIIn1�11u�IluluIIIIIIIIWl�VS7 n��r!=�ivi�� i! q1I��H 11ry�p1yrym'p ,,�QIt !i �■iit I 1' I I NII11111 r I' IIIII yi�l UP, �t��I 111�111tjt1t�1�1Ittttm�tImtt' IIII 11 pp IIIII IIIIIIIIII Itl 111111 irk'" /.I, f�i IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIn"•'illjli���/�'��■ij gypp"" mfl�m�j�INtI 1111111111111111111IIIIIII!::itll,lii;l'iIIII�G�/�aN■■ri�Itl1I�I1WI��dXlll1■IIIIIIINNIIItI , • 1 • I I IIIII. IIIIIII� ll� �' l�l�M F' D• ` �IIIi;I�I�III 11111111111111 III IIII IIIII 111 II ��II I, �'����"�:: I I IIIIIIIIIIIIIIIIIIIII IIIIIIIIIIIII III �IIi�HII��� �j •Im il�� I�iH�ii! �� �� �': • . IIIIIIIIIIIIIIIAI II 1 11 III I IIIIIII{IIII"II'�I' Ii�i' �I��lI! I I II i� IIi��N �,,1!� INI'lllll: �I�i!��.� ,, r�' I ■ iiiiiiilliliin''i!iliiii�iiliRi!ilil!i�!! li�• II „ IIIaI!I' I(II!IBilll�l��lii�ll ��'I NIII �yd!�II� III ��I!II!I!— ,�rril!I'h!ii0lnd ..1�1'i1�9�1 INS""MJ�"' .. I�Il�i�bi�ii�i��lllll NI • ����pllflp„N,iiiiyiiIiyiNl� 'A■"" �� II�yy�� ��1��11 �y,■pIIggI tl■191MIIIIIIp■�� 1 1 1 I 11 11 11 111 1 I Virginia Runoir Reduction Method Woraineet DEC, Virginia Runoff Reduction Method Re -Development Compliance Spreadsheet - Version 3.0 BMP Design Specifications List: 2013 Draft Stds & Specs Site Summary Project Title: Barnes Lumber Date: 44791 Total Rainfall (in): 43 Total Disturbed Acreage: 10.49 Site Land Cover Summary Pre-ReDevelopment Land Cover (acres) A soils BSolis CSoils DSoils Totals %of Total Forest/Open (acres) 0.00 1.65 0.00 0.8D 2.45 23 Managed Tud(acres) 0.00 2.61 0.00 1.79 4.40 42 I mpervious Cover (acres) 0.00 0.57 0.00 3.08 3.64 35 10.49 100 Post-ReDevelopment Land Cover (acres) A soils BS°ils CSoils DSoils Totals %of Total Forest/Open (acres) 0.00 0.00 0.00 0.00 0.00 0 Managed Turf(acres) 0.00 3.12 0.00 3.70 6.82 65 Impervious Cover (acres) 0.00 1.71 0.00 1.96 3.67 35 10.49 100 Site Tv and Land Cover Nutrient Loads Final Port -Development Post- pow Adjusted Pre- (Post-ReDevelopment ReDevelopment Development ReDevelopment &New Impervious) (New Impervious) Site Rv 0.48 0.49 0.95 0.43 Treatment Volume (its) 18,275 18,191 84 16,487 TP Load(Ib/yr) 11.48 11.43 0.05 10.36 Total TP Load Reduction Required (lb/yr) 3.19 3.14 0.04 Final Post -Development Load (Post-ReDevelopment & New Impervious) Pre- ReDevelopment TN Load (lb/yr) 1 82.14 73.75 Pre- ReDevelopment Final Post -Development Port-ReDevelopment TP TP Load per acre TP Load per acre Load per acre (lb/acre/yr) (lb/acre/yr) (lb/acre/yr) 0.99 1.09 1.09 Summary Print Virginia Runoff Reduction Method Worksheet Site Compliance Summary Maximum% Reduction Required Below 20% Pre-ReDevelopment Load Total Runoff Volume Reduction (k') 0 Total TP Load Reduction Achieved (lb/yr) 0.00 Total TN Load Reduction Achieved (lb/yr) 0.00 Remaining Post Development TP Load 11.48 (lb/yr) Remaining TP Load Reduction (lb/yr) 3.19 Required Summary Print Virginia Runoff Retlucfion Method Woftheet Drainage Area Summary D.A. A D.A. B DA. C D.A. D D.A. E Total Forest/Open (acres) 0.00 0.00 0.00 0.00 0.00 0.00 Managed Turf(acros) 0.00 0.00 0.00 0.00 0.00 0.00 Impervious Corer(acres) 0.00 0.00 0.00 0.00 0.00 0.00 Total Area (acres) 0.00 0.00 0.00 0.00 0.00 0.00 Drainage Area Compliance Summary DA. A D.A. B DA. C D.A. D D.A. E Total TP Load Reduced (lb/yr) 1 0.00 0.00 1 0.00 1 0.00 0.00 0.00 TN Load Reduced (lb/yr) 1 0.00 0.00 1 0.00 1 0.00 0.00 0.00 Summary Print Virginia Runoff Reduction Method Wofthest ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Runoff Volume and CN Calculations 1-year storm 2-year storm 10-year storm Target Rainfall Event (in) 1 0.00 0.00 0.00 Drainage Areas RV & CN Drainage Area A Drainage Area B Drainage Area C Drainage Area D Drainage Area E CN 0 0 0 0 0 RR (fta) 0 0 0 0 0 I -year return period RV wa R0.(wzin) 0.00 0.00 0.00 0.00 0.00 RV w RR(wiAn( 0.00 0.00 0.00 0.00 0.00 CN adjusted 0 0 0 0 0 2-year return period RVwo RR (wzin) 0.00 0.00 0.00 0.00 0.00 RV w RR (wsan( 0.00 0.00 0.00 0.00 0.00 CN adjusted 0 0 0 0 0 10-year return period RV wo RR(ws-in) 0.00 0.00 0.00 0.00 0.00 RV w RR(wzin( 0.00 0.00 0.00 0.00 0.00 CN adjusted 0 0 0 0 0 Summary Print Channel E - 10yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.039 ft/ft Left Side Slope 3.000 H:V Right Side Slope 3.000 H:V Discharge 2.77 cis Results Normal Depth 0.5 It Flow Area 0.7 ft2 Wetted Perimeter 3.2 ft Hydraulic Radius 0.2 ft Top Width 2.99 ft Critical Depth 0.6 ft Critical Slope 0.022 ft/ft Velocity 3.72 ft/s Velocity Head 0.21 ft Specific Energy 0.71 ft Froude Number 1.313 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.5 ft Critical Depth 0.6 ft Channel Slope 0.039 ft/ft Critical Slope 0.022 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frnB Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 1 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel D - 10yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.027 ft/ft Left Side Slope 4.000 H:V Right Side Slope 6.000 H:V Discharge 1.50 cis Results Normal Depth 0.3 It Flow Area 0.6 ft2 Wetted Perimeter 3.5 It Hydraulic Radius 0.2 It Top Width 3.48 It Critical Depth 0.4 It Critical Slope 0.024 ft/ft Velocity 2.48 ft/s Velocity Head 0.10 ft Specific Energy 0.44 ft Froude Number 1.050 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.3 ft Critical Depth 0.4 ft Channel Slope 0.027 ft/ft Critical Slope 0.024 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frnB Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 2 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel E - 2yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.039 ft/ft Left Side Slope 3.000 H:V Right Side Slope 3.000 H:V Discharge 1.83 cis Results Normal Depth 0.4 It Flow Area 0.5 ft2 Wetted Perimeter 2.7 It Hydraulic Radius 0.2 ft Top Width 2.56 It Critical Depth 0.5 ft Critical Slope 0.023 ft/ft Velocity 3.35 ft/s Velocity Head 0.17 ft Specific Energy 0.60 ft Froude Number 1.279 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.4 ft Critical Depth 0.5 ft Channel Slope 0.039 ft/ft Critical Slope 0.023 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frnB Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 3 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel D - 2yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.027 ft/ft Left Side Slope 4.000 H:V Right Side Slope 6.000 H:V Discharge 0.99 cis Results Normal Depth 0.3 It Flow Area 0.4 ft2 Wetted Perimeter 3.0 It Hydraulic Radius 0.1 It Top Width 2.97 It Critical Depth 0.3 ft Critical Slope 0.025 ft/ft Velocity 2.24 ft/s Velocity Head 0.08 ft Specific Energy 0.38 ft Froude Number 1.024 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.3 ft Critical Depth 0.3 ft Channel Slope 0.027 ft/ft Critical Slope 0.025 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frnB Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 4 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel C - 10yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.054 ft/ft Left Side Slope 4.000 H:V Right Side Slope 6.000 H:V Discharge 1.00 cfs Results Normal Depth 0.3 ft Flow Area 0.3 ft2 Wetted Perimeter 2.7 ft Hydraulic Radius 0.1 ft Top Width 2.61 ft Critical Depth 0.3 ft Critical Slope 0.025 ft/ft Velocity 2.93 ft/s Velocity Head 0.13 ft Specific Energy 0.39 ft Froude Number 1.427 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.3 ft Critical Depth 0.3 ft Channel Slope 0.054 ft/ft Critical Slope 0.025 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frnB Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 5 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel C - 2yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.054 ft/ft Left Side Slope 4.000 H:V Right Side Slope 6.000 H:V Discharge 0.66 cfs Results Normal Depth 0.2 It Flow Area 0.3 ft2 Wetted Perimeter 2.3 It Hydraulic Radius 0.1 It Top Width 2.24 It Critical Depth 0.3 ft Critical Slope 0.027 ft/ft Velocity 2.64 ft/s Velocity Head 0.11 ft Specific Energy 0.33 ft Froude Number 1.390 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.2 ft Critical Depth 0.3 ft Channel Slope 0.054 ft/ft Critical Slope 0.027 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frnB Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 6 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel B - 10yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.041 ft/ft Left Side Slope 3.000 H:V Right Side Slope 3.000 H:V Discharge 1.58 cis Results Normal Depth 0.4 It Flow Area 0.5 ft2 Wetted Perimeter 2.5 It Hydraulic Radius 0.2 It Top Width 2.39 It Critical Depth 0.4 ft Critical Slope 0.023 ft/ft Velocity 3.31 ft/s Velocity Head 0.17 ft Specific Energy 0.57 ft Froude Number 1.306 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.4 ft Critical Depth 0.4 ft Channel Slope 0.041 ft/ft Critical Slope 0.023 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frnB Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 7 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel B - 2yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.041 ft/ft Left Side Slope 3.000 H:V Right Side Slope 3.000 H:V Discharge 1.05 cis Results Normal Depth 0.3 It Flow Area 0.4 ft2 Wetted Perimeter 2.2 It Hydraulic Radius 0.2 It Top Width 2.05 It Critical Depth 0.4 ft Critical Slope 0.025 ft/ft Velocity 2.99 ft/s Velocity Head 0.14 ft Specific Energy 0.48 ft Froude Number 1.272 Flow Type Supercritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity Infinity ft/s Upstream Velocity Infinity ft/s Normal Depth 0.3 ft Critical Depth 0.4 ft Channel Slope 0.041 ft/ft Critical Slope 0.025 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frn8 Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 8 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel A - 10yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.017 ft/ft Left Side Slope 3.000 H:V Right Side Slope 3.000 H:V Discharge 14.99 cis Results Normal Depth 1.1 It Flow Area 3.6 ft2 Wetted Perimeter 7.0 It Hydraulic Radius 0.5 It Top Width 6.60 It Critical Depth 1.1 ft Critical Slope 0.017 ft/ft Velocity 4.13 ft/s Velocity Head 0.26 ft Specific Energy 1.37 ft Froude Number 0.980 Flow Type Subcritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity 0.00 ft/s Upstream Velocity 0.00 ft/s Normal Depth 1.1 ft Critical Depth 1.1 ft Channel Slope 0.017 ft/ft Critical Slope 0.017 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculation5.frn6 Center [10.03.00.03] 4/13/2022 27 Siemon Company Driw; Suite 200 W Page 9 of 10 Watertown, CT 06795 USA +1-203-755-1666 Channel A - 2yr Project Description Friction Method Manning Formula Solve For Normal Depth Input Data Roughness Coefficient 0.030 Channel Slope 0.017 ft/ft Left Side Slope 3.000 H:V Right Side Slope 3.000 H:V Discharge 9.92 cis Results Normal Depth 0.9 It Flow Area 2.7 ft2 Wetted Perimeter 6.0 It Hydraulic Radius 0.4 It Top Width 5.66 It Critical Depth 0.9 It Critical Slope 0.018 ft/ft Velocity 3.72 ft/s Velocity Head 0.21 ft Specific Energy 1.16 ft Froude Number 0.955 Flow Type Subcritical GVF Input Data Downstream Depth 0.0 ft Length 0.0 ft Number Of Steps 0 GVF Output Data Upstream Depth 0.0 ft Profile Description N/A Profile Headloss 0.00 ft Downstream Velocity 0.00 ft/s Upstream Velocity 0.00 ft/s Normal Depth 0.9 ft Critical Depth 0.9 ft Channel Slope 0.017 ft/ft Critical Slope 0.018 ft/ft Bentley Systems, Inc. Haestad Methods Solution FlowMaster Ditch Calculations.frnB Center 110.03.00.03] 4/13/2022 27 Siemon Company Drive Suite 200 W Page 10 of 10 Watertown, CT 06795 USA +1-203-755-1666 6/10/2020 Precipitation Frequency Data Server NOAA Atlas 14, Volume 2, Version 3 Location name: Crozet Virginia, USA* - � Latitude: 38.0683°, Longitude:-78.6962° i Elevation: 695.53 ft" `source: ESRI Maps "source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES G.M. Bonnin, D. Martin, B. Lin, T. Parzybok, M.Yekta, and D. Riley NOAA, National Weather Service, Silver Spring, Maryland PF tabular I PF graphical I Maps & aerials PF tabular PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Average recurrence interval (years) Duration 1�00 25I 50 I100 200 500 1000 5-min .3-0528 0.306-0 374 0.36 -0.448 0.43 0.486-0 595 0.546-0 671 0.591--0 730 0.633-0. 88 0.671-0.43 0.7113-0 913 0.747--0 972 0.766 10-min .862 �707 33.44 (0.49 0598 0.58760.17 0.693-0846 0.778-0952 0.8711 0.94211.16 1.017425 1082134 1. 11831753 0.676 0.814 0.968 1.09 1.23 1.34 1.44 1.53 1.64 1.72 15-min (0.612-0.748) (0.738-0.901) (0.876-1.07) (0.94-1.20) 1 (1.10-1.36) 1 (1.19-1.47) (1.27-1.58) (1.34-1.69) (1.42-1.82) (1.48-1.92) 30-min 0.839--11.02 1.02 1325 1.25-31852 1.4318.74 1.4 2?01 1.80 222 1.95 2042 2.09 2863 2.6 2a89 2. 973.11 60-min 1 05.1128 1.283156 1.60 1695 1.86-2.27 2. 8�67 2.43 3301 2. 83.34 2.93 3368) 3.24 4415 3. 94.54 2-hr 1. 3-31855 1. 0-61889 1. 8-12.37 2.21 2978 2.62 3631 2.96 3676 3. 04.22 3. 4-4.71 4. 9-5.39 4.475998 5.29 3-hr 135---11.71 1.4 2408 2.05 2.61 2.403 06 2. 6-3.65 3. 3-4.15 3. 04.67 3. 85?22 4. 9-5.99 4.91 666 1.96 2.37 2.95 3.47 4.18 4.79 5.43 6.13 7.13 8.02 6-hr (1.75-2.20) 1 (2.12-2.67) (2.62-3.32) (3.08-3.90) (3.67-4.69) (4.18-5.37) (4.69-6.11) (5.23-6.91) (5.98-8.07) (6.62-9.10) 2.49 3.01 3.75 4.43 5.40 6.25 7.19 8.22 9.74 11.1 12-hr 2.22-2.83 (2.68-3.42) 11 f3.33-4.26 (3.92-5.03) (4.72-6.11 (5.41-7.08) (6.13-8.15 (6.90-9.33) 8.00-11.1 (8.97-12.7) 3.06 3.70 4.72 5.57 6.82 7.89 9.06 10.4 12.3 14.0 24-hr (2.75-3.42) (3.334.14) 4.23-5.28) (4.98-6.21) (6.05-7.59) (6.95-8.77) 7.92-10.1) (8.95-11.5) 10.4-13.7) (11.7-15.5) 3.61 4.36 5.54 6.50 7.89 9.06 10.3 11.7 13.7 15.4 2 sly 3.25-4.02 3.4-4.87 4.98-6.17 5.83-7.24 7.02-8.77 8.9-10.1 9.4-11.5 10.2-13.0 11.7-15.3 13.0-17.2 4.65 5.89 6.91 8.38 9.61 10.9 12.4 14.5 16.3 3dayA3.84 3.48-4.26 4.22-5.15 5.34-6.53 6.247.65 7.53-9.27 8.57-10.6 9.68-12.1 10.9-13.7 12.6-16.1 13.9-18.1 4dayA4.07 (3.72-4.50) 4.93 (4.0-5.44) 6.25 (5.69-6.89) 7.32 (6.66-8.06) 8.87 (8.03-9.77) 10.2 (9.14-11.2) 11.6 (10.3-12.7) 13.1 (11.6-14.4) 15.3 (13.4-16.9) 17.7 (14.8-19.0) 4.72 5.69 7.11 8.27 9.91 11.3 12.7 14.3 16.5 18.4 7day 4.33-5.17 5.22-6.22 6.51-7.78 7.55-9.03 9.01-10.8 10.2-12.3 11.4-13.9 12.7-15.6 14.5-18.1 16.0-20.2 9 10-day 4.945782 5.94-898 7.3198.61 839-9.90 9.89-18.7 11.1-13.2 12.3-14.8 13.6-16.a 15.3- 8.7 16.7- 0.7 20-day 7.04 (6.58-7.57) 8.40 (7.85-9.02) 10.1 (9.45-10.9) 11.5 (10.7-12.3) 13.3 (12.4-14.3) 14.8 (13.6-15.9) 16.2 (14.9-17.5) 17.7 (16.2-19.1) 19.8 (18.0-21.4) 21.3 (19.3-23.2) 8.64 10.2 12.1 13.5 15.4 16.8 18.1 19.5 21.2 22.6 30-day (8.11-9.23) (9.62-10.9) (11.4-12.9) (12.7-14.4) (14.3-16.4) (15.6-17.9) (16.8-19.4) (18.0-20.8) (19.5-22.8) (20.7-24.3) 45-day 10.2-111.5 12.0- 3.5 14.10- 5.8 158-17.5 17.14--19.6 18 704.2 2 01 2.8 21 3- 4.3 22?8- 6.3 24 0- 7.8 60-day 12.7 14.9 17.1 18.8 20.9 22.5 24.0 25.4 27.1 28.4 (12.0-13.4) (14.1-15.7) (16.2-18.1) (17.8-19.9) (19.7-22.1) (21.2-23.7) (22.5-25.3) (23.8-26.8) (25.3-28.8) (26.4-30.2) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical hftps://hdsc.nws.noaa.gov/hdsc/pfds/pfds_Printpage.html?lat=38.0683&Ion=-78.6962&data=depth&units=english&series=pds 1/4 6/10/2020 Precipitation Frequency Data Server PDS-based depth -duration -frequency (DDF) curves Latitude: 38.06830, Longitude-78.69620 30 25 c 20 5 7 E E E E E L t t t t R R N N N M IO T A A N tl1 4b r� N 9 �pp pp pp N ref 6 O V19pp r�Y r�-I M 10 r-1 N M OlD Duration 25 5 n Average recurrence interval (years) NOAA Atlas 14, Volume 2, Version 3 Created (GMT): Wed Jun 10 14:45:45 2020 Back to Top Maps & aerials Small scale terrain Average recurrence interval (years) — 1 2 5 10 25 50 100 — 200 — 500 — 1000 Duration — 5mrn — 2-day — 10inin — 3-day 15-min — 44ay — 30min — 7-day — 60min — 10-day — 2-hr — 20-day — 3-hr — 30-day — 6-hr — 45-day — 12-hr — 50-day 24-hr hftps://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=38.0683&Ion=-78.6962&data=depth&units=english&series=pds 2/4 6/10/2020 Precipitation Frequency Data Server ane La e�scale,terrain Washington, D.C.' Harri:orburq S. raunIn �.� VIRGINIA NIA DWI - Ric Lynchburg larks' 100km ~ omi 4 r a .rs,7 Large scale map i H irrionbui(j / J _IJUI ljn t 11 01 r)U +Ri ch� Lynchburg Blackshurg ';Roanoke �y f`. 100km 1� � omi / N, Large scale aerial r hips://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=38.0683&Ion=-78.6962&data=depth&units=english&series=pds 3/4 6/10/2020 Precipitation Frequency Data Server US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service National Water Center 1325 East West Highway Silver Spring, MD 20910 Questions?: HDSC.Questions@noaa.gov Disclaimer hftps://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=38.0683&Ion=-78.6962&data=depth&units=english&series=pds 4/4