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WPO201500001 Calculations 2019-12-18
¶< PROWCT" MANAGEMENT H im in CIVIL.ENGINEERING LAND PLANNING • :ENGINES RING � ,,: o t--% November 4th, 2019 o U . Rif M, SHIMP • Emily Cox ic.No.45183 County of Albemarle 6 we / l 411! q : tip, Department of Community.Development • . o� .. Regarding: Northside Material Recovery Facility-VSMP Amendment SWM Plan ' , . . Dear Ms. Cox, Enclosed is the Stormwater Management Calculations Packet for the Northside Material Recovery Facility in Albemarle County. This project will disturb an area of 4.98 acres. The stormwater quality management strategy for this site is governed by the VRRM Development Spreadsheet. The site has a required TP Load Reduction of 4.28 lb/yr. This was calculated using the DEQ Virginia Runoff Reduction Method Re- : Development Compliance Spreadsheet. To satisfy the requirement nutrient credits will be purchased from a Nutrient Bank. The developer has already purchased_a total of 0.28 credits under the existing VSMP permit. The onsite detention pond will be converted into a Level 1 Biofilter, providing further VRRM credit. The remaining credit of:0:81 will be purchased to meet the water quality requirements. Runoff quantity will be managed through detention in the Biofilter. The runoff will be released at rates in compliance with the energy balance equation per.9VAC25-870-66-B-3.. The energy balance equation was .. applied to a point of analysis at the outlet of the SWM detention pond. The TR-55 Type 2 Method 1-year storm will generate a peak runoff that is less than or equal to the maximum allowable peak flow set forth by the energy balance equation. The pond shall have a standpipe with.an:appropriately sized 1-year orifice to.. meet these flows. See below for a summary of the peak runoff flow rates for the point of analysis. POA Drainage Area Summary:.. POA-1 Pre-Dev Runoff Max Q Post-Dev Post-Dev Runoff 1-Year Storm 8.44 cfs .. 4.58 cfs .. 3.77.cfs • 10-Year Storm 27.19 cfs .22.36 cfs APPROVED by the Albemarle County Community Deev S nent Department Date=��j.1( File Zv_.LS__.6 kJ_ aik`016: Contents: Pre-Development Stormwater Management Calculations Pre-Development Drainage Map Pre-Development HydroCAD Analysis Energy Balance Equation Summary Post-Development Stormwater Management Calculations Post-Development Drainage Map Post-Development Ditch Drainage Map Post-Development HydroCAD Analysis Stormwater Quality Calculations , Pre-Development VRRM Map Post-Development VRRM Map VRRM Spreadsheet Independent Reports Excerpt from NRCS Soils Report NOAA Precipitation Report 1- Pre-Development Drainage Area Summary i+*." SF AC SF AC SF AC SF AC SF AC ♦ + it_ III-III=_ - +•+•+• ` + =III=11El DA Area Impervious C Pervious Turf Woods LAND COVER PER 4 •;•;♦ 4TURF#+„ •; '; •+•11K�1 1 36,067 0.83 14,377 0.33 0.54 21,690 0.50 21,157 0.49 _57 0.01 ALBEMARLE COUNTY ' ' ''� ' ' ' ' ' ` -11 2 67,375 1.55 7,665 _ 0.18 0.37 59,710 1.37 50,584 1.16 8,186 0.19 4 + 4 + 4 + + + .4 i + 4 ♦ + « + 4- 3 173,812 3.99 12,558 0.29 0.34 161,254 3.70 161,444 3.71 00 0.00 GIS AERIAL MAP yr°.+ ' +++ a+'''',+4•%' •'''`-,`� III= Total« a +, + + 4 I I- 36067 6.36 34600 0.79 242654 5.57 233185 5.35 8738 0.20 (YEAR-2000) -- .y, • + ♦ 4 ♦ + + ♦ 4 <,F4a. }+a DA1= 0.83 AC , +*++a4+ 'v +a I-III-_ ♦ + 4'+ 14,377 SF IMPERVIOUS ++4+ +"� +;1 I 1=1 I - a+ + + « 44 +♦+; 4. 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Pre-Dev Drainage Area Map SCALE: 1 " = 100' ENGINSFRINGELANDPL9NMNG-PROJECT MANAGEMENT Latest Revision Date: Nov 8, 2019 012 EAST N.N STREET RHONE: <434) 227_8140 CHARLOTTESVILLE. VA 22902 JYi,IN4tsHIMI-ENOINEERINO.COM Pre-Development Stormwater Management Calculations Pre-Development Drainage Map Pre-Development HydroCAD Analysis Energy Balance Equation Summary Project: Northside Material Recovery Facility Prepared By: Shimp Engineering, P.C. Pre-Development HydroCAD Report 5-13-2019 1 2 3 DA-1 D -2 DA-3 I � � 4 POA-1 SubCat Reach '0n. Link Drainage Diagram for pre dev Prepared by Shimp Engineering, Printed 5/10/2019 HydroCADOO 9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Pre-Development pre dev Prepared by Shimp Engineering Printed 5/10/2019 HydroCADO 9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 2 Area Listing (all nodes) Area CN Description (acres) (subcatchment-numbers) 0.200 55 Woods,Good,HSG B (1,2) 4.690 69 50-75%Grass cover,Fair, HSG B (1,2,3) 0.800 98 Impervious (1,2,3) 5.690 TOTAL AREA Pre-Development pre dev Type II 24-hr 1-YR Rainfall=3.02" Prepared by Shimp Engineering Printed 5/10/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 3 Time span=5.00-24.00 hrs,dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Intl+Trans method - Pond routing by Stor-Ind method Subcatchment 1: DA-1 Runoff Area=0.830 ac 39.76%Impervious Runoff Depth>1.26" Tc=5.0 min CN=80 Runoff=1.89 cfs 0.087 af Subcatchment 2:DA-2 Runoff Area=0.860 ac 20.93%Impervious Runoff Depth>0.82" Tc=5.0 min CN=72 Runoff=1.23 cfs 0.059 af Subcatchment 3:DA-3 Runoff Area=4.000 ac 7.25%Impervious Runoff Depth>0.77" Tc=5.0 min CN=71 Runoff=5.33 cfs 0.257 af Link 4:POA-1 Inflow=8.44 cfs 0.403 af Primary=8.44 cfs 0.403 af Total Runoff Area=5.690 ac Runoff Volume=0.403 af Average Runoff Depth=0.85" 85.94%Pervious=4.890 ac 14.06%Impervious=0.800 ac Pre-Development pre dev Type II 24-hr 1-YR Rainfall=3.02" Prepared by Shimp Engineering Printed 5/10/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 4 Summary for Subcatchment 1: DA-1 [49] Hint:Tc<2dt may require smaller dt Runoff = 1.89 cfs @ 11.96 hrs, Volume= 0.087 af, Depth> 1.26" Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs,dt=0.05 hrs Type II 24-hr 1-YR Rainfall=3.02" Area(ac) CN Description * 0.330 98 Impervious 0.010 55 Woods, Good, HSG B 0.490 69 50-75%Grass cover, Fair, HSG B 0.830 80 Weighted Average 0.500 60.24%Pervious Area 0.330 39.76%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2: DA-2 [49] Hint:Tc<2dt may require smaller dt Runoff = 1.23 cfs @ 11.97 hrs, Volume= 0.059 af, Depth> 0.82" Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs,dt=0.05 hrs Type II 24-hr 1-YR Rainfall=3.02" Area(ac) CN Description * 0.180 98 Impervious 0.190 55 Woods, Good, HSG B 0.490 69 50-75%Grass cover, Fair, HSG B 0.860 72 Weighted Average 0.680 79.07%Pervious Area 0.180 20.93% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3: DA-3 [49] Hint: Tc<2dt may require smaller dt Runoff = 5.33 cfs @ 11.97 hrs, Volume= 0.257 af, Depth> 0.77" Pre-Development pre dev Type II 24-hr 1-YR Rainfall=3.02" Prepared by Shimp Engineering Printed 5/10/2019 HydroCAD®9.10 s/n 07054 0 2010 HydroCAD Software Solutions LLC Page 5 Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs, dt=0.05 hrs Type II 24-hr 1-YR Rainfall=3.02" Area(ac) CN Description 0.290 98 Impervious 0.000 55 Woods, Good, HSG B 3.710 69 50-75%Grass cover, Fair, HSG B 4.000 71 Weighted Average 3.710 92.75%Pervious Area 0290 7.25% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Link 4: POA-1 Inflow Area= 5.690 ac, 14.06%Impervious, Inflow Depth> 0.85" for 1-YR event Inflow = 8.44 cfs @ 11.97 hrs, Volume= 0.403 af Primary = 8.44 cfs @ 11.97 hrs, Volume= 0.403 af, Atten=0%, Lag=0.0 min Primary outflow= Inflow, Time Span=5.00-24.00 hrs, dt=0.05 hrs Pre-Development pre dev Type II 24-hr 10-YR Rainfall=5.53" Prepared by Shimp Engineering Printed 5/10/2019 HydroCADO 9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 6 Time span=5.00-24.00 hrs,dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1: DA-1 Runoff Area=0.830 ac 39.76%Impervious Runoff Depth>3.36" Tc=5.0 min CN=80 Runoff=4.94 cfs 0.232 af Subcatchment2: DA-2 Runoff Area=0.860 ac 20.93% Impervious Runoff Depth>2.61" Tc=5.0 min CN=72 Runoff=4.05 cfs 0.187 af Subcatchment3: DA-3 Runoff Area=4.000 ac 7.25%Impervious Runoff Depth>2.52" Tc=5.0 min CN=71 Runoff=18.21 cfs 0.841 af Link 4: POA-1 Inflow=27.19 cfs 1.260 af Primary=27.19 cfs 1.260 af Total Runoff Area=5.690 ac Runoff Volume=1.260 af Average Runoff Depth=2.66" 85.94% Pervious=4.890 ac 14.06%Impervious=0.800 ac Pre-Development pre dev Type II 24-hr 10-YR Rainfall=5.53" Prepared by Shimp Engineering Printed 5/10/2019 HydroCADO 9.10 s/n 07054 0 2010 HydroCAD Software Solutions LLC Page 7 Summary for Subcatchment 1: DA-1 [49] Hint: Tc<2dt may require smaller dt Runoff = 4.94 cfs @ 11.96 hrs, Volume= 0.232 af, Depth> 3.36" Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs, dt=0.05 hrs Type II 24-hr 10-YR Rainfall=5.53" Area(ac) CN Description 0.330 98 Impervious 0.010 55 Woods, Good, HSG B 0.490 69 50-75%Grass cover, Fair, HSG B 0.830 80 Weighted Average 0.500 60.24%Pervious Area 0.330 39.76%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2: DA-2 [49] Hint:Tc<2dt may require smaller dt Runoff = 4.05 cfs @ 11.96 hrs, Volume= 0.187 af, Depth> 2.61" Runoff by SCS TR-20 method, UH=SCS, Time Span=5.00-24.00 hrs,dt=0.05 hrs Type II 24-hr 10-YR Rainfall=5.53" Area(ac) CN Description 0.180 98 Impervious 0.190 55 Woods, Good, HSG B 0.490 69 50-75%Grass cover, Fair, HSG B 0.860 72 Weighted Average 0.680 79.07%Pervious Area 0.180 20.93% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3: DA-3 [49] Hint: Tc<2dt may require smaller dt Runoff = 18.21 cfs @ 11.96 hrs, Volume= 0.841 af, Depth> 2.52" Pre-Development pre dev Type II 24-hr 10-YR Rainfall=5.53" Prepared by Shimp Engineering Printed 5/10/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 8 Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs, dt=0.05 hrs Type II 24-hr 10-YR Rainfall=5.53" Area(ac) CN Description * 0.290 98 Impervious 0.000 55 Woods, Good, HSG B 3.710 69 50-75%Grass cover, Fair, HSG B 4.000 71 Weighted Average 3.710 92.75%Pervious Area 0.290 7.25%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Link 4: POA-1 Inflow Area= 5.690 ac, 14.06%Impervious, Inflow Depth> 2.66" for 10-YR event Inflow = 27.19 cfs @ 11.96 hrs, Volume= 1.260 of Primary = 27.19 cfs @ 11.96 hrs, Volume= 1.260 af, Atten=0%, Lag=0.0 min Primary outflow=Inflow, Time Span=5.00-24.00 hrs, dt=0.05 hrs Pre-Development pre dev Type II 24-hr 100-YR Rainfall=9.07" Prepared by Shimp Engineering Printed 5/10/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 9 Time span=5.00-24.00 hrs, dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1: DA-1 Runoff Area=0.830 ac 39.76%Impervious Runoff Depth>6.63" Tc=5.0 min CN=80 Runoff=9.42 cfs 0.458 af Subcatchment 2: DA-2 Runoff Area=0.860 ac 20.93%Impervious Runoff Depth>5.64" Tc=5.0 min CN=72 Runoff=8.57 cfs 0.404 af Subcatchment 3:DA-3 Runoff Area=4.000 ac 7.25%Impervious Runoff Depth>5.52" Tc=5.0 min CN=71 Runoff=39.09 cfs 1.839 af Link 4: POA-1 Inflow=57.07 cfs 2.701 af Primary=57.07 cfs 2.701 af Total Runoff Area=5.690 ac Runoff Volume=2.701 of Average Runoff Depth=5.70" 85.94% Pervious=4.890 ac 14.06%Impervious=0.800 ac Pre-Development pre dev Type II 24-hr 100-YR Rainfall=9.07" Prepared by Shimp Engineering Printed 5/10/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 10 Summary for Subcatchment 1: DA-1 [49] Hint:Tc<2dt may require smaller dt Runoff = 9.42 cfs @ 11.95 hrs, Volume= 0.458 af, Depth> 6.63" Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs,dt=0.05 hrs Type II 24-hr 100-YR Rainfall=9.07" Area(ac) CN Description * 0.330 98 Impervious 0.010 55 Woods, Good, HSG B 0.490 69 50-75%Grass cover, Fair, HSG B 0.830 80 Weighted Average 0.500 60.24%Pervious Area 0.330 39.76% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 2: DA-2 [49] Hint: Tc<2dt may require smaller dt Runoff = 8.57 cfs @ 11.96 hrs, Volume= 0.404 af, Depth> 5.64" Runoff by SCS TR-20 method, UH=SCS, Time Span=5,00-24.00 hrs, dt=0.05 hrs Type II 24-hr 100-YR Rainfall=9.07" Area(ac) CN Description * 0.180 98 Impervious 0.190 55 Woods, Good, HSG B 0.490 69 50-75%Grass cover, Fair, HSG B 0.860 72 Weighted Average 0,680 79.07%Pervious Area 0.180 20.93% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Subcatchment 3: DA-3 [49] Hint:Tc<2dt may require smaller dt Runoff = 39.09 cfs @ 11.96 hrs, Volume= 1.839 af, Depth> 5.52" Pre-Development pre dev Type II 24-hr 100-YR Rainfall=9.07" Prepared by Shimp Engineering Printed 5/10/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 11 Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs,dt=0.05 hrs Type II 24-hr 100-YR Rainfall=9.07" Area(ac) CN Description * 0.290 98 Impervious 0.000 55 Woods, Good, HSG B 3.710 69 50-75%Grass cover, Fair, HSG B 4.000 71 Weighted Average 3.710 92.75%Pervious Area 0.290 7.25%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 5.0 Direct Entry, Summary for Link 4: POA-1 Inflow Area= 5.690 ac, 14.06%Impervious, Inflow Depth > 5.70" for 100-YR event Inflow = 57.07 cfs @ 11.95 hrs, Volume= 2.701 of Primary = 57.07 cfs @ 11.95 hrs, Volume= 2.701 af, Atten=0%, Lag=0.0 min Primary outflow= Inflow,Time Span=5.00-24.00 hrs, dt=0.05 hrs Energy Balance Equation Summary Shimp Engineering, P.C. 9/27/2019 NORTHSIDE DR. 24 Hr 1 year Storm: POA 1 �1 `•�developed5-I•F• Qpre-developed RVPre-Developed) RVdeveloped Qdeveloped�(Qforested*RVforested)/RVdeveloped Drainage Area : 5.46 Ac Qpre-developed = 8.44 RVpre-Developed = 0.403 MaX Qdeveloped = 4.58 cfs RVDeveloped = 0.594 Post Development Runoff Peak Flow=3.77 cfs, meets 9VAC25-870-66-B(3) Post Development Q10=22.36 cfs Post-Development Stormwater Management Calculations Post-Development Drainage Map Post-Development Ditch Drainage Map Post-Development HydroCAD Analysis Li Post-Development Drainage Area Summary / / SF AC SF AC SF AC SF AC SF AC V / DA Area Area Impervious Impervious C Pervious Pervious Turf Turf Woods Woods ° /� �c� 1 161,043 3.70 104,354 2 40 0.69 56,689 1.30 40,550 0.93 16,139 0.37 } 1/�rlJ 2 76,534 1.76 19,541 0.45 0.45 56,993 1.31 48,304 1.11 8689 0.20 ♦ [SS••Jr rr/l 4 k c Yo pJz e, /.'I\ ` r40 Total 237577.00 5.45 123895.00 2.84 - 113682.00 2.61 88854.00 2.04 24828.00 0.57 o B 4 c ,--� a%♦ ; hi *Q e2�b iv ma - 4, zgkD J414•0*. ,*."�TaN ♦ �bY044, Y / r,�A,.5 t DA1= 3.70 AC 4= a,,., �' //'1//; 2.40 AC IMPERVIOUS 1 / 94'� /�. •I. ���2 littf X,'// 4 tt //1 if'.of ,,,, i - -. / . ,_ C ) '. TURF ( ,,''J�. fr . .. , ,)_ ,„ , ,,, .3/4 ,Q,,,,,,,...„,... „ • „ . e / ...„_,,,, I 0.45 AC IMPERVIOUS -: � \�� i\ o /° .2 J.f 1 - / '(xrr r 1 1. , �� `� � '� r_ IMPERVIOUS�� •-� � ` � � . a 44 4�pYe )k �. . .' �--f a♦. Apo of rr- rN o.e 7?et 7•e � • '1 1 ,I} , , �'k 1. ' . -4i--- ) •••:: i 04, p,, S. ( ' 11,ki A'.l ; ) t�`�\ WOODS--:,,i- ./4..4,,,.... ellilibith*'"-- Iiihib... P A P PO • te .• A 7 • ns' ,� 9 / ^\\ �► `` 480 'T,ys Tit4itk1. 0470 n l 1 444 , ' ,�, a 9-} (RTE 1570) 100 0 100 200 300 Northside Drive Material Recovery Facility: SHIMPENGINEERING P.C. L _ _ _ _-II Post-Dev Drainage Area Map SCALE: 1 " = 100' ENGINEERING-LAND PLANNING-PROJECT MANAGEMENT Latest Revision Date: Nov. 8, 201 9 012 EAST HIGH STREET PHONE: (43A) 227_0140 CNARLOTTESVILLE. VA 22S02 JUSTINSSNIMP-CNOINCCRINO.COM Northside Material Recovery Facility Modified LD-268 Roadside and M edian Ditch Design Form J Side Slope Min Mac _ Earth / Ditchti .. A CA To Q 110 0.2 COO _:1 L -1 R slap. Slope AlavaCle_ , T-yr 10-yr and : Matting Type Freeboard FVFt Vebdty Val' Chanel SF AC NCR ACC FV'Ft Vel.' Veloaty DeptR ''''',. ti 1 JJ/ 1 OSO 102384 235 118 118 5.0 5.39 _ 7.� 6.34 829 4 _ 4 0.03 0.25 40 335 0.18 EC-2 7YPE1 1.22 202 N. Uj li 2 p5p 39648 091 046 0.46 5.0 5.39 7C6 245 121 4 4 0.C6 0.10 4.0 240 0.19 EC-2 lYPE1 1.81 2C0- ,., / •3 - _ - _ - _ - - - 13.46 26,94 2 _ 2 0.03 0.10 7.0 _ 5.78 1.43 EC-3 TYPE 1.07 250 T /?JJ QQx Virreo ' 2-yr Velocity calculations performed us no steepest slope&2-yr low 44144. P Tl( \y ili` Iql, ?J BJ� � 101 r Depth calculation pa-brined is tog shatlovest slope a 10-yr kw 7 et"! ,� •3F B7 • J: �_ 4�lI.G `` 4�-,B4.'i -Flo.rates per HydroCAD Model OI,, °atszae49:4° `au.'�1`` ynk r �20e�_�JJ�T 4"� 1 s i!��, Ill:. ad .ems \Itl� '+w s�Y` Y �� ( / , -II I 4i-. \ "; DITCH 1=2.35 AC !%i`.-,"l', , , 4,-.)„ , , , , .....„,.,..„..„„ „ • ..:-,,,...,..i,„ . . dir.,ii,...elt...le..,41.... i / • *��r#III,1/ / f -, at __,/; - � 41 TURF �_� C\, A,� SO ? 'P LC N.N.....? 9 11 . , f , ----'-',.......7,----, ----...„.\ 4;1) -/ t, \ / i ' DITCH 2=JC \\\�� �' s IMPERVIOUS v �'� -.'"--4........„, \- ':: ::.:. .... \______„V ':: _ w. ga44044 ae a'.f. of � i \\,:''""...le .2.--'''''',\--- ) -./.. \� ; 4,,,,0 4.,:,eite P44114. \ s :\ 4 . . , r ��+tr P \ \ 4.) \ k.,,•.- \ /,,,,ire. as +3,,��"r ' DIRECT TO BMP=1.81 AC h"f`\T. \( `�"�R"' y'�s._° '1 } ,, \\4160.1.0. ,,_ o \\\ WOODS 8,0\jt,17:::;....,'''-it,'1\.,., ..., NI1111141t (-... 1 1 / , -- \i 1armiiii .,.\„, .. 7 y` "qP \ \ ' -'15 gas ` a ° P "tiny / .„_______ii ---- ;27,1233°--0.3. 9 c ........____ d ��WWW 100_ _ _ 0 100 200 300 Northside Drive Material Recovery Facility: SHIIIP�NGINE RING P,C. L _ _ Ditch Drainage Area Map SCALE: 1 " = 100' ENGINEERING-LAND PLANNING-PROJECT MANAGEMENT Latest Revision Date: Nov. 8, 2019 012 CAST HIGH SHIRT .NONE: (434) 227-0140 CHARLOTTESVILLE, VA 22902 .AISTINESHIMP-CNOINEERINO.COM Post-Development HydroCAD Report Project: Northside Material Recovery Facility Created By: Shimp Engineering, P.C. 1 � Date: 9-27-2019 (2______S) DA-1 DA-2 I 3P BIOFILTER 4L POA-1 Subcat Reach on. Link Drainage Diagram for post dev --\\____ Prepared by Shimp Engineering, Printed 10/1/2019 HydroCADOO 9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Post-Development post dev Type II 24-hr 1-YR Rainfall=3.02" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 2 Time span=5.00-24.00 hrs,dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S:DA-1 Runoff Area=3.700 ac 15.68%Impervious Runoff Depth>1.46" Tc=14.5 min CN=83 Runoff=7.06 cfs 0.449 af Subcatchment 2S:DA-2 Runoff Area=1.760 ac 25.57%Impervious Runoff Depth>0.97" Tc=14.6 min CN=75 Runoff=2.14 cfs 0.142 af Pond 3P:BIOFILTER Peak Elev=486.53' Storage=6,247 cf Inflow=9.20 cfs 0.592 af Outflow=3.77 cfs 0.585 af Link 4L:POA-1 Inflow=3.77 cfs 0.585 af Primary=3.77 cfs 0.585 af Total Runoff Area=5.460 ac Runoff Volume=0.592 af Average Runoff Depth=1.30" 81.14%Pervious=4.430 ac 18.86%Impervious=1.030 ac Post-Development post dev Type II 24-hr 1-YR Rainfall=3.02" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 3 Summary for Subcatchment 1S: DA-1 Runoff = 7,06 cfs @ 12.07 hrs, Volume= 0.449 af, Depth> 1.46" Runoff by SCS TR-20 method, UH=SCS,Time Span=5,00-24.00 hrs, dt=0.05 hrs Type II 24-hr 1-YR Rainfall=3.02" Area(ac) CN Description • 0.580 98 Impervious 0.370 55 Woods, Good, HSG B 0.930 69 50-75%Grass cover, Fair, HSG B • 1.820 92 Stock Piles of Stone 3.700 83 Weighted Average 3.120 84.32% Pervious Area 0.580 15.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.5 Direct Entry, Summary for Subcatchment 2S: DA-2 Runoff = 2.14 cfs @ 12.08 hrs, Volume= 0.142 af, Depth> 0.97" Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs, dt=0.05 hrs Type II 24-hr 1-YR Rainfall=3.02" Area(ac) CN Description • 0.450 98 Impervious 0.200 55 Woods, Good, HSG B 1.110 69 50-75%Grass cover, Fair, HSG B 1.760 75 Weighted Average 1.310 74.43%Pervious Area 0.450 25.57%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.6 Direct Entry, Summary for Pond 3P: BIOFILTER Inflow Area= 5.460 ac, 18.86%Impervious, Inflow Depth> 1.30" for 1-YR event Inflow = 9.20 cfs @ 12,07 hrs, Volume= 0.592 of Outflow = 3.77 cfs @ 12.27 hrs, Volume= 0.585 af, Atten=59%, Lag= 11.9 min Primary = 3.77 cfs @ 12.27 hrs, Volume= 0.585 af Routing by Stor-Ind method,Time Span=5.00-24.00 hrs,dt=0.05 hrs Post-Development post dev Type II 24-hr 1-YR Rainfall=3.02" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD0 9.10 s/n 07054 0 2010 HydroCAD Software Solutions LLC Page 4 Peak Elev=486.53'@ 12.27 hrs Surf.Area=5,296 sf Storage=6,247 cf Plug-Flow detention time=23.0 min calculated for 0.583 af(99%of inflow) Center-of-Mass det.time=16.4 min(860.8-844.4) Volume Invert Avail.Storage Storage Description #1 482.30' 14,681 cf Custom Stage Data(Prismatic)Listed below(Recalc) Elevation Surf.Area Voids Inc.Store Cum.Store (feet) (sq-ft) (%) (cubic-feet) (cubic-feet) 482.30 4,000 0.0 0 0 484.30 4,000 40.0 3,200 3,200 486.30 5,153 20.0 1,831 5,031 488.00 6,200 100.0 9,650 14,681 Device Routing Invert Outlet Devices #1 Primary 482.30' 24.0" Round Culvert L=30.0' CPP,end-section conforming to fill, Ke=0.500 Inlet/Outlet Invert=482.30'/482.00' S=0.0100'/' Cc=0.900 n=0.020 Corrugated PE,corrugated interior #2 Device 1 482.30' 6.0"Vert.Orifice/Grate X 2.00 C=0.600 #3 Device 1 487.00' 48.0" Horiz.Orifice/Grate C=0.500 Limited to weir flow at low heads #4 Primary 487.70' 60.0'long x 8.0'breadth Broad-Crested Rectangular Weir Head(feet) 0,20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef,(English) 2.43 2.54 2.70 2,69 2.68 2.68 2.66 2.64 2.64 2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74 Primary OutFlow Max=3.77 cfs@ 12.27 hrs HW=486.53' (Free Discharge) -1=Culvert (Passes 3.77 cfs of 25.96 cfs potential flow) E2=Orifice/Grate (Orifice Controls 3.77 cfs @ 9.60 fps) 3=0rifice/Grate (Controls 0.00 cfs) -4=Broad-Crested Rectangular Weir(Controls 0,00 cfs) Summary for Link 4L: POA-1 Inflow Area= 5.460 ac, 18.86%Impervious, Inflow Depth > 1.29" for 1-YR event Inflow = 3.77 cfs @ 12.27 hrs, Volume= 0.585 of Primary = 3.77 cfs @ 12.27 hrs, Volume= 0.585 af, Atten=0%, Lag=0.0 min Primary outflow= Inflow,Time Span=5.00-24.00 hrs, dt=0.05 hrs Post-Development post dev Type II 24-hr 10-YR Rainfall=5.53" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 5 Time span=5,00-24.00 hrs, dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1S:DA-1 Runoff Area=3.700 ac 15.68%Impervious Runoff Depth>3.65" Tc=14.5 min CN=83 Runoff=17.47 cfs 1.124 af Subcatchment2S: DA-2 Runoff Area=1.760 ac 25.57%Impervious Runoff Depth>2.88" Tc=14.6 min CN=75 Runoff=6.61 cfs 0.422 af Pond 3P:BIOFILTER Peak Elev=487.58' Storage=12,133 cf Inflow=24.07 cfs 1.546 af Outflow=22.36 cfs 1.536 af Link 4L:POA-1 Inflow=22.36 cfs 1.536 af Primary=22.36 cfs 1.536 af Total Runoff Area=5.460 ac Runoff Volume=1.546 af Average Runoff Depth=3.40" 81.14% Pervious=4.430 ac 18.86%Impervious=1.030 ac Post-Development post dev Type II 24-hr 10-YR Rainfall=5.53" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Pane 6 Summary for Subcatchment 1S: DA-1 Runoff = 17.47 cfs @ 12.06 hrs, Volume= 1.124 af, Depth> 3.65" Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs,dt=0.05 hrs Type II 24-hr 10-YR Rainfall=5.53" Area(ac) CN Description * 0.580 98 Impervious 0.370 55 Woods, Good, HSG B 0.930 69 50-75%Grass cover, Fair, HSG B * 1.820 92 Stock Piles of Stone 3.700 83 Weighted Average 3.120 84.32%Pervious Area 0.580 15.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.5 Direct Entry, Summary for Subcatchment 2S: DA-2 Runoff = 6.61 cfs @ 12.07 hrs, Volume= 0,422 af, Depth> 2.88" Runoff by SCS TR-20 method, UH=SCS, Time Span=5.00-24.00 hrs,dt=0.05 hrs Type II 24-hr 10-YR Rainfall=5.53" Area(ac) CN Description * 0.450 98 Impervious 0.200 55 Woods, Good, HSG B 1.110 69 50-75%Grass cover, Fair, HSG B 1.760 75 Weighted Average 1.310 74.43%Pervious Area 0.450 25.57% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.6 Direct Entry, Summary for Pond 3P: BIOFILTER Inflow Area= 5.460 ac, 18.86%Impervious, Inflow Depth> 3.40" for 10-YR event Inflow = 24.07 cfs @ 12.06 hrs, Volume= 1.546 af Outflow = 22.36 cfs @ 12.12 hrs, Volume= 1.536 af, Atten=7%, Lag=3.4 min Primary = 22.36 cfs @ 12.12 hrs, Volume= 1.536 af Routing by Stor-Ind method, Time Span=5.00-24.00 hrs, dt=0.05 hrs Post-Development post dev Type II 24-hr 10-YR Rainfall=5.53" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 7 Peak Elev=487.58'@ 12.12 hrs Surf.Area=5,942 sf Storage= 12,133 cf Plug-Flow detention time=19.3 min calculated for 1.532 of(99%of inflow) Center-of-Mass det,time=15.5 min(833.4-817.9) Volume Invert Avail.Storage Storage Description #1 482.30' 14,681 cf Custom Stage Data(Prismatic)Listed below(Recalc) Elevation Surf.Area Voids Inc.Store Cum.Store (feet) (sq-ft) (%) (cubic-feet) (cubic-feet) 482.30 4,000 0.0 0 0 484.30 4,000 40,0 3,200 3,200 486.30 5,153 20.0 1,831 5,031 488.00 6,200 100.0 9,650 14,681 Device Routing Invert Outlet Devices #1 Primary 482.30' 24.0" Round Culvert L=30.0' CPP,end-section conforming to fill, Ke=0.500 Inlet/Outlet Invert=482.30'/482,00' S=0.0100'1 Cc=0.900 n=0.020 Corrugated PE,corrugated interior #2 Device 1 482.30' 6.0"Vert.Orifice/Grate X 2.00 C=0,600 #3 Device 1 487.00' 48.0"Horiz.Orifice/Grate C=0.500 Limited to weir flow at low heads #4 Primary 487.70' 60.0'long x 8.0'breadth Broad-Crested Rectangular Weir Head(feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef.(English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64 2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74 Primary OutFlow Max=21.46 cfs@ 12.12 hrs HW=487.56' (Free Discharge) -1=Culvert (Passes 21.46 cfs of 30.80 cfs potential flow) L2=OrificelGrate (Orifice Controls 4.23 cfs @ 10.78 fps) 3=Orifice/Grate (Weir Controls 17.23 cfs @ 2.45 fps) -4=Broad-Crested Rectangular Weir(Controls 0.00 cfs) Summary for Link 4L: POA-1 Inflow Area= 5.460 ac, 18.86%Impervious, Inflow Depth> 3.38" for 10-YR event Inflow = 22.36 cfs @ 12.12 hrs, Volume= 1.536 of Primary = 22.36 cfs @ 12.12 hrs, Volume= 1.536 af, Atten=0%, Lag=0.0 min Primary outflow= Inflow,Time Span=5.00-24.00 hrs, dt=0.05 hrs Post-Development post dev Type II 24-hr 100-YR Rainfall=9.07" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 8 Time span=5.00-24,00 hrs,dt=0.05 hrs, 381 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Subcatchment 1 S:DA-1 Runoff Area=3.700 ac 15.68%Impervious Runoff Depth>6.98" Tc=14.5 min CN=83 Runoff=32.52 cfs 2.151 af Subcatchment2S:DA-2 Runoff Area=1.760 ac 25.57% Impervious Runoff Depth>6.00" Tc=14.6 min CN=75 Runoff=13.61 cfs 0.880 af Pond 3P:BIOFILTER Peak Elev=487.90' Storage=14,076 cf Inflow=46.12 cfs 3.031 af Outflow=45.49 cfs 3.018 af Link 4L:POA-1 Inflow=45.49 cfs 3.018 af Primary=45.49 cfs 3.018 af Total Runoff Area=5.460 ac Runoff Volume=3.031 af Average Runoff Depth =6.66" 81.14% Pervious=4.430 ac 18.86% Impervious=1.030 ac Post-Development post dev Type II 24-hr 100-YR Rainfall=9.07" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 9 Summary for Subcatchment 1S: DA-1 Runoff = 32.52 cfs@ 12.06 hrs, Volume= 2.151 af, Depth> 6.98" Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs, dt=0.05 hrs Type II 24-hr 100-YR Rainfall=9.07" Area(ac) CN Description * 0.580 98 Impervious 0.370 55 Woods, Good, HSG B 0.930 69 50-75%Grass cover, Fair, HSG B * 1.820 92 Stock Piles of Stone 3.700 83 Weighted Average 3.120 84,32% Pervious Area 0.580 15.68% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.5 Direct Entry, Summary for Subcatchment 2S: DA-2 Runoff = 13.61 cfs@ 12.06 hrs, Volume= 0.880 af, Depth> 6.00" Runoff by SCS TR-20 method, UH=SCS,Time Span=5.00-24.00 hrs, dt=0.05 hrs Type II 24-hr 100-YR Rainfall=9.07" Area(ac) CN Description * 0.450 98 Impervious 0.200 55 Woods, Good, HSG B 1.110 69 50-75%Grass cover, Fair, HSG B 1.760 75 Weighted Average 1.310 74.43%Pervious Area 0.450 25.57% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 14.6 Direct Entry, Summary for Pond 3P: BIOFILTER Inflow Area= 5.460 ac, 18.86%Impervious, Inflow Depth> 6.66" for 100-YR event Inflow = 46.12 cfs@ 12.06 hrs, Volume= 3.031 af Outflow = 45.49 cfs @ 12.08 hrs, Volume= 3.018 af, Atten= 1%, Lag= 1.3 min Primary = 45.49 cfs @ 12.08 hrs, Volume= 3.018 af Routing by Stor-Ind method, Time Span=5.00-24.00 hrs, dt=0.05 hrs Post-Development post dev Type II 24-hr 100-YR Rainfall=9.07" Prepared by Shimp Engineering Printed 10/1/2019 HydroCAD®9.10 s/n 07054 ©2010 HydroCAD Software Solutions LLC Page 10 Peak Elev=487.90'@ 12.08 hrs Surf.Area=6,140 sf Storage= 14,076 cf Plug-Flow detention time=15.6 min calculated for 3.018 af(100%of inflow) Center-of-Mass det.time=12.9 min(812.6-799.7) Volume Invert Avail.Storage Storage Description #1 482.30' 14,681 cf Custom Stage Data(Prismatic)Listed below(Recalc) Elevation Surf.Area Voids Inc.Store Cum.Store (feet) (sq-ft) (%) (cubic-feet) (cubic-feet) 482.30 4,000 0.0 0 0 484.30 4,000 40.0 3,200 3,200 486.30 5,153 20.0 1,831 5,031 488.00 6,200 100.0 9,650 14,681 Device Routing Invert Outlet Devices #1 Primary 482.30' 24.0" Round Culvert L=30.0' CPP, end-section conforming to fill, Ke=0.500 Inlet/Outlet Invert=482.30'/482.00' S=0.01001' Cc=0.900 n=0.020 Corrugated PE,corrugated interior #2 Device 1 482.30' 6.0"Vert.Orifice/Grate X 2.00 C=0.600 #3 Device 1 487.00' 48.0" Horiz.Orifice/Grate C=0.500 Limited to weir flow at low heads #4 Primary 487.70' 60.0'long x 8.0'breadth Broad-Crested Rectangular Weir Head(feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 Coef.(English) 2.43 2.54 2.70 2.69 2.68 2.68 2.66 2.64 2.64 2.64 2.65 2.65 2.66 2.66 2.68 2.70 2.74 Primary OutFlow Max=44.58 cfs@ 12.08 hrs HW=487.89' (Free Discharge) -1=Culvert (Barrel Controls 32.21 cfs @ 10.25 fps) L2=Orifice/Grate (Passes<4.37 cfs potential flow) 3=Orifice/Grate (Passes<34.68 cfs potential flow) -4=Broad-Crested Rectangular Weir(Weir Controls 12.37 cfs @ 1.07 fps) Summary for Link 4L: POA-1 Inflow Area= 5.460 ac, 18.86%Impervious, Inflow Depth> 6.63" for 100-YR event Inflow = 45.49 cfs @ 12.08 hrs, Volume= 3.018 af Primary = 45.49 cfs @ 12.08 hrs, Volume= 3.018 af, Atten=0%, Lag=0.0 min Primary outflow= Inflow,Time Span=5.00-24.00 hrs, dt=0.05 hrs Northside Material Recovery Facility Modified LD-268 Roadside and Median Ditch Design Form I Side Slope Min. Max Earth Ditch C A CA Tc 12 110 02 010 :1 L :1 R Slope Slope Allowable 2-yr 0-yr Matting Type Hoard Channel Ft/Ft Velocity n=.03 Depth SF AC INCR ACC Ft/Ft Vel.* Velocity Depth 1 0.50 102384 2.35 1.18 1.18 5.0 5.39 7.05 6.34 8.29 4 4 0.08 0.25 4.0 3.35 0.18 EC-2 TYPE 1 1.82 2.00 2 0.50 39648 0.91 0.46 0.46 5.0 5.39 7.05 2.45 3.21 4 4 0.06 0.10 4.0 2.40 0.19 EC-2 TYPE 1 1.81 2.00 *3 - - - - - - - - 13.46 26.94 2 2 0.09 0.10 7.0 5.78 1.43 EC-3 TYPE I 1.07 2.50 2-yr Velocity calculations performed using steepest slope&2-yr flow 10-yr Depth calculation performed using shallowest slope&10-yr flow `Flow rates per HydroCAD Model Stormwater Quality Calculations Pre-Development VRRM Map Post-Development VRRM Map VRRM Spreadsheet Virginia Runoff Reduction Method Worksheet DEQ Virginia Runoff Reduction Method Re-Development Compliance Spreadsheet -Version 3.0 BMP Design Specifications List: 2013 Draft Stds&Specs Site Summary Project Title:NORTHSIDE DRIVE Date:43738 Total Rainfall(in): 43 Total Disturbed Acreage: 4.98 Site Land Cover Summary Pre-ReDevelopment Land Cover (acres) A soils B Soils C Soils D Soils Totals %of Total Forest/Open(acres) 0.00 0.00 0.00 0.00 0.00 0 Managed Turf(acres) 0.00 0.00 0.00 4.22 4.22 85 Impervious Cover(acres) 0.00 0.00 0.00 0.76 0.76 15 4.98 100 Post-ReDevelopment Land Cover (acres) A soils B Soils C Soils D Soils Totals %of Total Forest/Open(acres) 0.00 0.00 0.00 0.00 0.00 0 Managed Turf(acres) 0.00 0.00 0.00 2.10 2.10 42 Impervious Cover(acres) 0.00 0.00 0.00 2.88 2.88 58 4.98 100 Site Tv and Land Cover Nutrient Loads Pre- Final Post-Development Post- Final Post-Development Post-ReDevelopment TP Post- Adjusted Pre- ReDevelopment (Post-ReDevelopment Development TP Load per acre Load per acre &New Impervious) ReDevelopment (New Impervious) ReDevelopment TP Load per acre (Ib/acre/yr) (Ib/acre/yr) (Ib/acre/yr) Site Rv 0.65 0.44 0.95 0.44 0.99 1.49 0.99 Treatment Volume(ft3) 11,837 4,527 7,311 4,527 TP Load(Ib/yr) 7.44 2.84 4.59 2.84 Total TP Load Reduction Required(Ib/yr) 4.29 0.57 3.72 Final Post-Development Load Pre- (Post-ReDevelopment&New Impervious) ReDevelopment TN Load(Ib/yr) 53.21 28.99 Summary Print Virginia Runoff Reduction Method Worksheet Site Compliance Summary Maximum%Reduction Required Below 20"% Pre-ReDevelopment Load Total Runoff Volume Reduction(ft3) 3,710 Total TP Load Reduction Achieved(Ib/yr) 3.20 Total TN Load Reduction Achieved(Ib/yr) 26.65 Remaining Post Development TP Load (Ib/yr) 4.24 Remaining TP Load Reduction(Ib/yr) 1.09 Required Summary Print Virginia Runoff Reduction Method Worksheet Drainage Area Summary D.A.A D.A.B D.A.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(acres) 1.10 0.00 0.00 0.00 0.00 1.10 Impervious Cover(acres) 2.40 0.00 0.00 0.00 0.00 2.40 • Total Area(acres) 3.50 0.00 0.00 0.00 0.00 3.50 Drainage Area Compliance Summary D.A.A D.A.B D.A.C D.A.D D.A.E Total TP Load Reduced(Ib/yr) 3.20 0.00 0.00 0.00 0.00 3.20 TN Load Reduced(Ib/yr) 26.65 0.00 0.00 0.00 0.00 26.65 Summary Print Virginia Runoff Reduction Method Worksheet Drainage Area A Summary Land Cover Summary A Soils B Soils C Soils D Soils Total %of Total Forest/Open(acres) 0.00 0.00 0.00 0.00 0.00 0 - Managed Turf(acres) 0.00 0.00 0.00 1.10 1.10 31 Impervious Cover(acres) 0.00 0.00 0.00 2.40 2.40 69 3.50 BMP Selections Managed Turf Impervious TP Load from BMP Treatment Untreated TP Load TP Removed TP Remaining Downstream Treatment Practice Credit Area Cover Credit Upstream Volume(fta) to Practice(Ibs) (lb/yr) (Ib/yr) to be Employed (acres) Area(acres) Practices(Ibs) 6.a.Bioretention#1 or Micro-Bioretention #1 or Urban Bioretention(Spec#9) 1.1 2.4 9,274.65 0.00 5.82 3.20 2.62 Total Impervious Cover Treated(acres) 2.40 Total Turf Area Treated(acres) 1.10 Total TP Load Reduction Achieved in D.A. (lb/yr) 3.20 Total TN Load Reduction Achieved in D.A. (Ib/yr) 26.65 Summary Print Virginia Runoff Reduction Method Worksheet Runoff Volume and CN Calculations 1-year storm 2-year storm 10-year storm Target Rainfall Event(in) 2.97 3.59 5.42 Drainage Areas RV&CN Drainage Area A Drainage Area B Drainage Area C Drainage Area D Drainage Area E CN 92 0 0 0 0 RR(ftt) 3,710 0 0 0 0 RV wo RR(ws-in) 2.13 0.00 0.00 0.00 0.00 1-year return period RV w RR(ws-in) 1.84 0.00 0.00 0.00 0.00 CN adjusted 89 0 0 0 0 RV we RR(ws-in) 2.72 0.00 0.00 0.00 0.00 2-year return period RV w RR(ws-in) 2.43 0.00 0.00 0.00 0.00 • CN adjusted 89 0 0 0 0 • RV wo RR(ws-in) 4.50 0.00 0.00 0.00 0.00 10-year return period RV w RR jws-in) 4.21 0.00 0.00 0.00 0.00 CN adjusted 89 0 0 . 0 0 Summary Print 27B 1-_ t-III=_ # 1=III=III-= LAND COVER PER :#++i++ + III=11E1 III- * * * * * * * _ ALBEMARLE COUNTY +*+*+ TURF. 4 +++++*+ -111 cd M- , +•♦ + + i 4-• I CIS AERIAL MAP * » * * * ♦ a +- + -i I (YEAR-2000) 17 a , +# + + i + : +� I�I I SOIL TYPE.2%*N* SOILTYPE + 4 + +• � + + + + +2 ++#++�I I I= I- + '+JfS * + + + 4 + _ ♦+ t#/ +*+*++++♦+++ 1 ++++ '++*+ - M r4 + # + i + .�4 + + I 1 t +l++ + + # 4 f 1 I \ 1I 27C ++*+*+*,**++, ", $N ✓• C ,* •z.lvt. III-I I1= is ,"av° �i*A*,*,*,*,+,+ SCRAP CARS ° - . fc�i'S! :dr.:�.� ..: I '. # +. + 1 + 4 � ,. I I El I El I -_ 1 1 E11 -III-III-I I Ell 1= ON GRAVEL ''„,.. ` `, •s ,1' •`.e•. 1 t-111=lll=t 11-� II I I I I 1-111-1 11=111- v + +` +*+�•++,**� } r'': 4+�„"sY'�« 3 I t 1-111-I I 1-I I 1-ll -)I 1-111-III-111-t l 1-111 • BARE SOIL .te r 111-t l i=1l El 11=111-1 1 111-111-111-111-111-111=11 y - + + + + .+ # + �+ + 4 y2 � »�x -;, =��r=1^I I t I-111-111 III I IIll=1I1-1 I I-1 I I-t I I= (,�(��. 4+4*4+*##4�+*♦+f* Y'i a#+*•4*++•+ - 'i"` � j �y , /� 3� I��I I-Ilt�l t' 11111=11 III-III-III-IIIIII-111-111-1I1-II �.,;:.,4.=,.. +*+*1*# +*tJ+*+*+*ji:*\ ', *i*#*+*i+++:* = , CAY';':' . 4._ 11 - 1 IlaIIIII 1 1IlIIIIlIII=III=III=III=1111I III I . i + i i s + + + �! + ♦ 4 4 + + + + + + R T'' '.+3 �� Y• 1 t I I-1 I I Il 11 1-I t I-I 11-I 1 I-1 11-t 1 I I t 1 K. 1 # + + + + # 4 4 4 ♦ 1 # # + 4 ',; I i' • f ♦ 4 4 + • 4 4 + + i + r < r 1-t1 11 t1t=11 I-I III-111-111-tll-Ilt-111-11t-t I I-t 11' + 1 + + + µ # +/+ + + + ♦ , ♦ ♦ + + + - •Cr'?a'_.r'y41 r r.. .r r t EI 1 1--tl�tll-111-1I1-Ilt-Ill-111-Ill-111-111 T i + + + 4 + +!+ + + + i + + + ♦ 4 4 4 + + ,7 • ' M + 4 + +/4 # ,+ + + + +fff aa 4 4 ♦4.+ + + + �f�^- :` r < f 11-t t t 1=1 1 1 1=1I1=111=111=1I1=111=t11=111- 1 + + DRIVEWAY r 1 1 I IIII_1 I I-t1t=111=1 1 =t 1 1=1II=111=111= T F �8 .y,aai:a.-..a..,.. i + i 4 + + + + + + + + �-� rt `-- • ♦ +'i+# + • r -Ili-i l _11�4 y� ,r 'xTi:di�..T12.1 u- * + # # 4 + + - ♦ 4 4 4 4 + 4 t + + 4 + + f.'4 + 4 ♦ +: " - r t I� If= 11 tll 111 I11 I 1 1 N ?�a ....... GRAVEL LOT = -=4 �- t ___ - I III 1 III II Illltltlt tt III III III IIII II III= III1111 .c..7i..7•*L a ♦ + a 4 ♦ * + + a 4 4 + + + 4 + + # + ♦ ♦ '♦ 4 + 4 h ,..,:,,:....,,,„,:.. ,,,,a,,, ,, ri i I t=1 I F=1 I t-I I I�1 11-1 I I-I ,�,- 1 1 1 1 1 1 t t 111 T i`va%rawmu=`[i4G ' ♦ + + ♦ + -♦ /+ + + + + + + + ♦ 4 ♦ + + ♦ '";;''''''''.*-4;''''''''"''''''''''''''''''' -"<1 }r , 1 _111=1 I t-- 1 .l 111III -t I I- �I111111I111111 Y:r a�' "(i + 4 4 + i ♦ { ♦ 4 4 + + 4 + + + + + + 4 t ♦ f + + 4 4 4 + h /- - / 4 -� « + + + + + 1+ + 4 + + + + } + + + + + + *.. ♦ • + + 4 +. ',` I t-t I -lll-t I I-I 1 I-I 1 1-1 I t-1 F *+ 4 + + � 4 + + 4 . + + +'+ }*+ + +'+ + + + , + + + + -Il- 11I- 11 / -' ->>. -111-111-111-III111 v • + , ♦ + + t 4 + + + + + + + + { � ,'=" 1 1=111=111=111 +*+ + + 4 + 4 + f + + +'+'+'+'+ + +' + + + ♦ 4 + k4. _III-II-111=tl -III '% III=III=III= f+ . ,+a+•*+•*+•++*+4.+ T•;++*+J4/*� +++'+ • ++a*a++++*4*a*++++a'+'a++*+*a++*4+++f*_+ -4*+*4:aaCa-+ + �y+ -I11-II -111-I11-I11-I�./ /% !/ r I11-111-1 S + *-* = * * + + 4 + + ++ a * * + * * + * + + +-* + + * * * 'f_ • I III-III 111-111-III-t '' '' ' ' 4 + + .i. + + t._ + + ++ ++4 +++ + + + + + +-4'+ + ++ + + 4 ♦ + + +I+ + + =R\ _ /!: '%!- 34D r`a4ia'x 4 + 4 4 + k + f ,'. ♦/4 + + + + + } a + + + + ♦ ♦ ♦ ', # + 4 # ti /'' I-1It It=t1� III- - 3T,." + 1 4 # 4 + 3 + 7 4J♦ ++ + '+ + + ' 1 + + tt + ++++ •*+ + i +- --' + +I+ 4 ++++a ... //--� ,"/ // iTaaa_ ♦ a + 4 * + \+ µ'` T ♦ 4 + % a + + + + + + + + + * # :111 , '" "_t'' ,< a a * ++ *# ♦ ♦ 4 + + + *+4 + + + t'.-a + la-i ft a* +*+ _ �/ p + + + i + + + .'.♦ + 44+ ++•** f 4 f + ♦ ♦ 4 + +* a + +++ i .4 4 4 4 4 4j 4* ++++ + .ry ` I j, ��i''i//''j''' * * ♦ * * * * ♦ 4 {O + • a + + + + +' + # + + + + +,'� f *4* a + l'I I-� ' + + + + + + i +* * 4+ # 4! 4 4 + 4 4 + *++++4+# + +' +'* ✓A'•+* ++* +*# ' -� �- J' '--" ' ' a a + + ♦ + f �. +a+ a+ + 4 + ♦ + ♦ ♦ + +* ' + + ,,4 +*+ + 4 4 + + *+ + *III 1--11-11 �i�''- ,�/ _. + + + + + + i 4 •'' + +*+ a + 4 !+ 4 + ♦ 4.4+ 4 ++4 +*+*+ 4. + 4-'+++ +44 +++++')++++++4• d .'+ + I I-I I I-I // .,A.R # 4 a + + + + ,' ; ♦ 1 4 + + + + 4 + + + 4 A + • + + .t + Land Use Schedule + + + + 4 4 + + •.4 + + +++ 4++++ + + 4;uRF ♦ + + + + + 4 + #Y+ * * + + 4 +r + + + + • # +* •+ • i 4 ♦ + + 4 + ♦ + a . a + + + + 4 + + + ; + '� ' +-+ + + + + 4 + + ♦ ,t AI I-I I t- + + + +'+ + + ' y' -♦ i + + + i + ♦ + + a + + 4 + f + + 4 4 + + + + 4, + +A.1 4*--.4 + + -.„-..-4 . * +"-M ''''''' + +• +• + a ♦• r< +• •♦• + * 4 + 4 a + + + + ♦ ♦ ♦ + 4 + , +,-s:,4 + • +'+ a x _ *a*+'+*+* y' - ''/ Exisiin SF AC -.: + . + #*4+♦ + ,.♦ 4 + +•' •+* a•' •+ + # 4 + a + + ♦ + ♦ 4 +a + ,,' -+''4 +•+ 4 4/j., + + III-III=1 _., 4 4 g # i ♦ + .� + + + +*+++ +'+++++ 4 4.4 # + + + 1 + + 4 +. + + + .,4,+ + + a " + _` �''/ O'' l ji,f ;. + ' -111-111-111=�� Building 0 0.00 0.0/o a a + + ♦ i",+ + a a a a + + + + + + a + + + + + ✓>Y ✓+' 4 + .... 4 + a a + + /,�'� y 4 + + + + + + + 4 + 4 +* + + + + i + + + ++le* -4,4;'i--4„ + +4+ + 4 4 i + 4. + a t 1-III-III-I 1 I-I • a 4 4 # ';' 4 + +'+ } + + + • 4 a 4 + 4 4 4 a + 4 # + , �� 4'-44 ' ,..S4+ + '+a* -. * + + t 1=woods I=1 t I Gravel 18652 0.43 8.6% 4 4 + + + + + + + + a • + + * + + 4 +*+ + # ♦ "+' 4 + + 4 + 4 A 4+ -II�_. i + + + + I+ _.+ 4 + • a *+ + + + + + + + ++ + -+ + + + '+ + + + * + 4- ** -1 I I-t I 1-III - + + f 4 4•++++4+a a + 4 4 + 4 + 4 ++4 + 4 + + + + + 4 4*a + +*. Soil 14242 0.33 6.6 + + + I+ ` + + + + + 4 + + + + + + + + + + + + + + + +�.t + a++ I=1 I-I 1 It ` '' ♦ 4 + +•+ + + # +, +4 a + + i + + + 4 + 4 + 4 + 4 + 4,4- +*4 + .L'j' ; + * � • * • - ;+ * 4 + + * } + ++4 * + * + * �a # a*+ i�T ImperviolsArea 32890 0.76 15.2% ,fit' •+ + + l + . r + a•4 a+ • 4+a+ 4 + + + *+o + +*+*+ + + 4,-�. + + +l ♦ +" + + 4 4 +*+ + a + + + + + + + 4 + +�''+,+*+ + + + +- +-:+=+ - j �, ♦ + .: ♦ i 4 .+ + + + + a + + + 4 4'+ + 4 4 a 4 ♦ i x_- Turf 184,039 4.22 8 4.8 + + # ♦ + a ++ +- *+ + ♦ +!+ r '+ *•*+ -+'+,"4.+ +*+ . + + + + + 4 + # * + .x + 4 + + + + + + + + . + . + �- + + ♦ +,, + + 1' Woods 0 0.00 0.0% 1 ' ;+: +• • • • • Total 216929 498 100.0% * * 4 + 4 + + 4 44 + + +! � _ �+ + + + + i + + + + + + + + + + a 4++ ♦. +• + +. +. ♦,'4 as + ++ F. 4 + + + ,':'- y / ,.' . -. ,I, -,,, R + '�+ + �s + 4 + 4 + I+ + j =- t ♦, } � i' +"4+* + + 1 a i + + - <� ; qo + + i+4 44. t�* i "�"4*+ , s/s . + + s 4}.a + 4 * + + + + ,,.; Proposed SF AC * * * '+*+ + * . A 4 + ♦ 1�4 +*4 4 * 44� * * * * * * * Building 0 0.00 0.0% �.. '� -:-. 1 f + + +++ + +++ + +. , :'+ + + + a, is-i + + + + + + + + + + + r- g 0 Stock Pile 79 217 1.82 36.5/o /- a +fr • :„.:::::: ' + '♦*+ + * a * * Gravel464501.0721.4%:,.. + +r+ ♦ + +/ ous Area ° 0 1 t T -• i f Im pervi 125667 2 88 57 9 �> =% ""-' > >�-:fT Turf 91,262 2.10 42.1 '' i ° 0.00 /•_ Woods 0 0.0 ° ,' IMITS OF DISTURBANCE= 4.98 AC �_ Total 216,929 4.98 100.0°/ 0 100 0 100 200 300 Northside Drive Material Recovery Facility: SHIMPENGINEERING, P, C. •■•■ ■•■•■ Pre-Dev VRRM Map SCALE: 1 " = 100' ENGINEERING-LAND PL FLAMING-PROJECT M4V4GEMEVT Latest Revision Date: Nov 8, 2019 012 EAST HIGH 5T,euT PHONE: (434) 227_5140 CHARLOTTESVILLE. VA 32902 JUSTINOSHILIP-ENGINEERING.COM 1 27B II ' :: LI:P° l� . J _ SOIL TYPE / SOIL TYPE • ( r I N0 / hiA:::::%.' , - / , 7 � Silk / ,_ • •� � TURF •. - i .,,,, �� h \ it �_��, `BO/ ' / :' ti ♦�• / � 88 �''� / # IMPERVIOUS Ailli / ♦�� 34D � '. � • IMPERVIOUS ( - '''''',/ e \ \ ,):+ Pf• 0 / iC') WOODS Land Use Schedule 1 ' Existing SF AC % ' / / �r o Building 0 0.00 0.0/o .•.•itta. / `�. Gravel 18652 0.43 8.6% ! / `•�, Sod 14,242 0.33 6.6/0 Airihim" ,. \ �rnimuu �.'�� ''�+i�♦ / ir��' �� Impervious Area 32890 0.76 15.2% j ``j ` ����' \• , Turf 184,039 4.22 84.8% ,; •.:��� i woods 0 0.00 0.0% y� Total 216,929 4.98 100.0% i ---, , ��� Proposed SF AC /o �'''�� ��' • as° Building 0 0.00 0.0°!0 ' _ ""'" v ' Stock Pile 79,217 1.82 36.5% Gravel 46450 1.07 21.4% __- 4,_____-____._ _ Impervious Area 125667 2.88 57.9% _ — _-- Turf 91,262 2.10 42.1% IMITS OF DISTURBANCE= 4.98 AC Woods 0 0.00 0.0% Total 216,929 4.98 100.0% 100_ _ _ 0 100 200 300 Northside Drive Material Recovery Facility: SIIII7PENGINEERING, P.C. L - _ _ _ Post-Dev VRRM Map ENGI ERIuc-LAND PLANNING-PROJECT MaNAGEMENT SCALE: 1 " = 100' Latest Revision Date: Nov 8, 2019 912 EAST HIGH STREET PHONE: (434) 227_5140 CHARLOTTESVILLE. VA 22902 JUSTINOSHIMP-ENGINEERINO.COM Independent Reports Excerpt from NRCS Soils Report NOAA Precipitation Report USDA United States A product of the National Custom Soil Resource i� Department of Cooperative , 1111111. Agriculture a joint effort ofSoil theSurvey United Report for RCS States Department ofAgricutureand other A I be m` a rl e Federal agencies, State Natural agencies including the Resources Agricultural Experiment County, Vi rg i n i a Conservation Stations, and local Service participants lib — r� ?('A �] ' / ., � / j # " JJ Ri . it .. %, • 41 I y '1g- f �k ma �l+l�y F • r: r Jr `/1/ r ti� if/f� mckiiir a e f tj 41 March 24, 2015 Custom Soil Soil ResourceMap Report in mN En n 724800 724870 724940 725010 725080 725150 725220 725290 725360 725430 725500 36°8'44"N 38°8'44 N ' ' rt'-'-..-'- • it! . " * Nr 7:/ . -1I--,.."-,,t,::-- ,i �� ..yr e �Qf �N F .E,r�.. g � ,A t.. 4 p 27G f. !/' r T a • ,'3.. / ice`" c•�. �' i el • 1Nr �' • d . " Abr ."�. .. 444 ..'":' q,,:, ,'=',' ler,`x'4;` r _, ,‘ yS M d*y� A1' . f #.`kC +it* , * i , u I 38°8 29"^. 724800 3 724870 724940 725010 725080 725150 725220 725290 725360 725430 725500 3 rn Map Scale:1:3,330 if printed on A landscape(11"x 8,5')sheet ^ rn Meters N nN 0 45 90 180 270 �' /VFeet 0 0 150 300 600 90 Map projection:Web Mercator Comer coordinates:WGS84 Edge bcs:UTM Zone 17N WGS84 8 Custom Soil Resource Report MAP LEGEND MAP INFORMATION Area of Interest(AOI) f#4 Spoil Area The soil surveys that comprise your AOI were mapped at 1:15,800. n Area of Interest(AOI) a Stony Spot Soils Very Stony Spot Warning:Soil Map may not be valid at this scale. l Soil Map Unit Polygons `. Wet Spot Enlargement of maps beyond the scale of mapping can cause ,,No Soil Map Unit Lines misunderstanding of the detail of mapping and accuracy of soil line Other • Soil Map Unit Points placement.The maps do not show the small areas of contrasting .• Special Line Features soils that could have been shown at a more detailed scale. Special Point Features to Blowout Water Features Streams and Canals Please rely on the bar scale on each map sheet for map ., Borrow Pit measurements. Transportation X Clay Spot Rails Source of Map: Natural Resources Conservation Service 0 Closed Depression ry Interstate Highways Web Soil Survey URL: http://websoilsurvey.nrcs.usda.gov X Gravel Pit US Routes Coordinate System: Web Mercator(EPSG:3857) Gravelly Spot Major Roads Maps from the Web Soil Survey are based on the Web Mercator 0 Landfill Local Roads projection,which preserves direction and shape but distorts distance and area.A projection that preserves area,such as the A. Lava Flow Background Albers equal-area conic projection,should be used if more accurate dll. Marsh or swamp . Aerial Photography calculations of distance or area are required. • Mine or Quarry This product is generated from the USDA-NRCS certified data as of O Miscellaneous Water the version date(s)listed below. O Perennial Water Soil Survey Area: Albemarle County,Virginia v Rock Outcrop Survey Area Data: Version 10, Dec 11,2013 ..- Saline Spot Soil map units are labeled(as space allows)for map scales 1:50,000 . •• Sandy Spot or larger. g Severely Eroded Spot Date(s)aerial images were photographed: May 9,2011—Jun 4, Sinkhole 2011 Slide or Slip The orthophoto or other base map on which the soil lines were • Sodic Spot compiled and digitized probably differs from the background imagery displayed on these maps.As a result,some minor shifting of map unit boundaries may be evident. 9 Custom Soil Resource Report Map Unit Legend Albemarle County,Virginia(VA003) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 2D Albemarle fine sandy loam,15 to 3.1 11.0% 25 percent slopes 21B Culpeper fine sandy loam,2 to 7 1.7 6.1% percent slopes 27B Elioak loam,2 to 7 percent 0.9 3.0% slopes 27C Elioak loam,7 to 15 percent 1.8 6.4% slopes 34D Glenelg loam, 15 to 25 percent 2.0 7.0% slopes 47C Louisburg sandy loam,7 to 15 2.3 8.1% percent slopes 88 Udorthents, loamy 15.9 56.2% W Water 0.6 2.2% Totals for Area of Interest 28.3 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management.These are called contrasting.or dissimilar,components.They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the 10 Custom Soil Resource Report Albemarle County, Virginia 2D—Albemarle fine sandy loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: kb99 Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost-free period: 195 to 231 days Farmland classification: Farmland of statewide importance Map Unit Composition Albemarle and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Albemarle Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from metasedimentary rock Typical profile H1 - 0 to 5 inches: fine sandy loam H2- 5 to 30 inches: clay loam H3-30 to 38 inches: sandy loam H4 - 38 to 50 inches: bedrock H5- 50 to 79 inches: bedrock Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: 35 to 60 inches to paralithic bedrock; 40 to 60 inches to lithic bedrock Natural drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water(Ksat): Moderately high (0.20 to 0.57 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Low (about 5.9 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C 12 Custom Soil Resource Report 21 B—Culpeper fine sandy loam, 2 to 7 percent slopes Map Unit Setting National map unit symbol: kb8k Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost-free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Culpeper and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Culpeper Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from meta-arkosic sandstone and quartzite Typical profile H1 - 0 to 8 inches: fine sandy loam H2- 8 to 30 inches: clay H3- 30 to 37 inches: sandy clay loam H4 - 37 to 45 inches: fine sandy loam H5- 45 to 50 inches: bedrock H6- 50 to 79 inches: bedrock Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: 40 to 79 inches to lithic bedrock; 40 to 79 inches to paralithic bedrock Natural drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water(Ksat): Very low to high (0.00 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Moderate (about 6.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2e Hydrologic Soil Group: B 13 Custom Soil Resource Report 27B—Elioak loam, 2 to 7 percent slopes Map Unit Setting National map unit symbol: kb8y Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost-free period: 195 to 231 days Farmland classification: All areas are prime farmland Map Unit Composition Elioak and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Elioak Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from mica schist Typical profile H1 - 0 to 8 inches: loam H2- 8 to 39 inches: silty clay H3-39 to 79 inches: silt loam Properties and qualities Slope: 2 to 7 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water(Ksat): Moderately high to high (0.20 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Moderate (about 6.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 2e Hydrologic Soil Group: B 14 Custom Soil Resource Report 27C—Elioak loam, 7 to 15 percent slopes Map Unit Setting National map unit symbol: kb8z Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost-free period: 195 to 231 days Farmland classification: Farmland of statewide importance Map Unit Composition Elioak and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Elioak Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from mica schist Typical profile H1 - 0 to 8 inches: loam H2- 8 to 39 inches: silty clay H3-39 to 79 inches: silt loam Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water(Ksat): Moderately high to high (0.20 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Moderate (about 6.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B 15 Custom Soil Resource Report 34D—Glenelg loam, 15 to 25 percent slopes Map Unit Setting National map unit symbol: kb9m Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost-free period: 195 to 231 days Farmland classification: Farmland of statewide importance Map Unit Composition Glenelg and similar soils: 80 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Glenelg Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from mica schist Typical profile H1 - 0 to 8 inches: loam H2- 8 to 28 inches: silty clay loam H3-28 to 80 inches: loam Properties and qualities Slope: 15 to 25 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: High Capacity of the most limiting layer to transmit water(Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: High (about 9.7 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 4e Hydrologic Soil Group: B 16 Custom Soil Resource Report 47C—Louisburg sandy loam, 7 to 15 percent slopes Map Unit Setting National map unit symbol: kbbs Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost-free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Louisburg and similar soils: 75 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Louisburg Setting Landform: Hillslopes Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from granite and gneiss Typical profile H1 - 0 to 5 inches: sandy loam H2- 5 to 79 inches: sandy loam Properties and qualities Slope: 7 to 15 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Runoff class: Low Capacity of the most limiting layer to transmit water(Ksat): High to very high (5.95 to 19.98 in/hr) Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Available water storage in profile: Moderate (about 6.6 inches) Interpretive groups Land capability classification (irrigated): None specified Land capability classification (nonirrigated): 6e Hydrologic Soil Group: A 17 Custom Soil Resource Report 88—Udorthents, loamy Map Unit Setting National map unit symbol: kbfy Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F Frost-free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Udorthents and similar soils: 85 percent Minor components: 3 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Udorthents Setting Landform: Interfluves Landform position (two-dimensional): Summit Landform position (three-dimensional): Interfluve Down-slope shape: Convex Across-slope shape: Convex Parent material: Residuum weathered from granite and gneiss Properties and qualities Slope: 2 to 25 percent Depth to restrictive feature: More than 80 inches Depth to water table: More than 80 inches Frequency of flooding: None Frequency of ponding: None Minor Components Wehadkee Percent of map unit: 3 percent Landform: Flood plains Down-slope shape: Linear Across-slope shape: Linear W—Water Map Unit Setting National map unit symbol: kbgk Mean annual precipitation: 25 to 65 inches Mean annual air temperature: 54 to 59 degrees F 18 Custom Soil Resource Report Frost-free period: 195 to 231 days Farmland classification: Not prime farmland Map Unit Composition Water: 100 percent Estimates are based on observations, descriptions, and transects of the mapunit. 19 5/13/2019 Precipitation Frequency Data Server NOAA Atlas 14,Volume 2,Version 3 40*" - , Location name:Charlottesville,Virginia, USA* I'`�"�' ...ILatitude:38• .1437°,Longitude: -78.431° mu •`i, Elevation:512.36 ft** "'a e.� *source:ESRI Maps 'r o� "t°� **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 inc_he s)1 Duration Average recurrence interval(years) J 1 2 5 10 25 i 50 [ 100 1 200 500 1000 J 0.348 0.416 0.489 0.550 0.621 0.676 I 0.728 0.778 0.839 0.889 5-min (0.314-0.386) (0.376-0.461) (0.441-0.540) (0.495-0.608) (0.556-0 684) (0.602-0.744)j(0.645-0.802) (0.684-0.857) (0.730-0.928) (0.766-0.986) 0.556 0.665 0.783 0.879 0.989 1.08 1.16 1.23 1.33 1.40 10-min (0.502-0.616) (0.601-0.737) (0.706-0.865) (0.791-0.972) (0.886-1.09) (0.959-1.19) (1.02-1.27) (1.08-1.36)1.08-1.36 ( (1.151.�-.47) (1.21- 1.5_ 15-min 0.695 0.836 0.990 1.11 1.25 1.36 1.46 1.56 1.67 1.76 (0.628-0.770) (0.755-0.926) (0.893-1.09) (1.00-1.23) (1.12-1.38) (1.21-1.50) (1.30-1.61) (1.37-1.71) (1.45-1.85) (1.51-1.95) 30-mln 0.953 1.16 1.41 1.61 1.86 2.05 2.24 2.42 2.66 2.85 (0.861-1.06) (1.04-1.28) (1.27-1.56) (1.45-1.78) (1.66-2.05) (1.83-2.26) (1.98-2.47) (2.13-2.67) (2.31-2.94) (2.45-3.16) 60-min 1.19 1.45 1.80 2.10 2.47 2.78 3.09 3.40 3.81 4.15 (1.07-1.32) (1.31-1.61) (1.63-1.99) (1.89-2.32) (2.21-2.73) (2.48-3.06) (2.73-3.40) (2.99-3.74) (3.32-4.22) (3.58-4.61) 2-hr 1.43 1.74 2.17 2.56 3.05 3.46 3.89 4.35 4.98 5.52 (1.27-1.61) (1.54-1.96) (1.93-2.45) (2.26-2.88) (2.68-3.43) (3.03-3.89) (3.39-4.37) (3.75-4.88) (4.25-5.60) (4.65-6.22) 3-hr 1.56 1.90 2.37 2.78 3.33 3.79 4.26 4.76 5.46 6.07 (1.38-1.78) (1.67-2.16) (2.09-2.71) (2.44-3.17) (2.90-3.78) (3.28-4.29) (3.67-4.83) (4.07-5.40) (4.61-6.21) I (5.06-6.991) 6-hr 1.99 2.40 2.98 3.51 4.22 4.85 5.51 6.22 7.25 8.15 (1.76-2.26) (2.13-2.73) (2.63-3.39) (3.08-3.98) (3.69-4.79) (4.20-5.48) (4.72-6.22) (5.28-7.04) (6.06-8.21) I (6.72-9.25) 12-hr 2.49 3.00 3.74 4.43 5.39 6.25 1 7.18 1 8.21 9.74 11.1 (2.20-2.85) (2.66-3.43) (3.30-4.27) (3.89-5.05) (4.69-6.13) (5.38-7.09) (6.11-8.15) (6.90-9.31) (8.02-11.1) (9.01-12.7) 24-hr 2.97 3.59 4.59 5.42 6.66 7.71 8.88 10.2 12.1 13.7 (2.66-3.34) (3.22-4.05) (4.10-5.16) (4.83-6.09) (5.90-7.46) (6.79-8.62) (7.74-9.91) (8.77-11.3) l (10.3.13.5) (11.5-15.3) 2-day 3.50 4.24 5.38 6.33 7.69 8.84 10.1 11.4 13.4 15.0 (3.15-3.91) (3.82-4.73) (4.84-6.01) (5.67-7.05) (6.85-8.55) (7.81-9.81) (8.84-11.2) (9.95-12.7) (11.5-15.0) (12.8-16.8) 3-day 3.72 4.51 5.73 6.73 8.18 9.39 10.7 12.1 14.2 15.9 (3.38-4.13) (4.09-5.00) (5.19-6.35) (6.08-7.45) I (7.35-9.04) (8.38-10.4) (9.48-11.8) (10.7-13.4) (12.3-15.7) I (13.7-17.7) 4-day 3.95 4.78 6.07 7.13 8.66 9.95 11.3 12.8 15.0 16.8 (3.61-4.36) (4.37-5.27) (5.53-6.69) (6.49-7.84) I (7.84-9.52) (8.95-10.9) (10.1-12.5) (11.4-14.1) (13.2-16.5) (14.6-18.6) 4.59 5.53 6.91 8.04 9.67 11.0 12.5 14.0 16.3 18.1 7-day (4.20-5.04) (5.06-6.06) (6.31-7.58) (7.33-8.82) (8.77-10.6) (9.95-12.1) (11.2-13.7) (12.5-15.4) (14.3-17.9) (15.7-20.0) 10-day 6.25 7.72 8.91 10.6 12.0 13.4 14.9 17.1 18.8 (4.79-5.67) (5.75-6.80) (7.09-8.38) (8.17-9.67) (9.66-11.5) (10.9-13.0) (12.1-14.5) (13.4-16.2) (15.2-18.6) (16.6-20.6) 20-day 6.85 8.17 9.87 11.2 13.0 14.4 15.9 17.4 19.4 1 20.9 (6.40-7.37) (7.63-8.78) (9.20-10.6) (10.4-12.0) (12.1-14.0) (13.3-15.5) (14.6-17.1) (15.9-18.7) (17.6-20.9) (18.9-22.7) 30-day 8.40 9.97 11.8 13.2 15.0 16.4 17.7 19.0 20.7 22.0 (7.89-8.98) (9.36-10.6) (11.1-12.6) (12.3-14.0) (14.0-16.0) (15 2 17.4) (16.4-18.9)� (17.6-20.3) (19.1-22.2) I (20 2 23.7) 45-day 10.5 12.4 14.5 16.1 18.1 19.5 21.0 22.4 24.1 25.4 (9.90-11.2) (11.7.13.2) (13.6-15.4) (15.1-17.0) (17 0-19.1) (18 3 20.7) (19 6-22.3) ( (20.8-23.8) I (22.4-25.7) (23.5-27.2) 12.3 14.5 16.7 18.4 20.5 22.1 23.6 25.0 26.8 28.1 6"ay (11.7-13.0) (13.7-15.3) (15.8-17.7) (17.4-19.4) (19.3-21.7) (20.8-23.3) (22.1-24.9) (23.4-26.4) (25.0-28.4) (26.1-29.8) 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 https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=38.1437&Ion=-78.4310&data=depth&units=english&series=pds 1/4