Loading...
HomeMy WebLinkAboutWPO201600083 Calculations WPO VSMP 2017-05-08PROJMAASHimp1 , CIVECTIL ENGINEERING NGEMENT LAND PLANNING ENGINEERINGa • February 14, 2017 Matt Wentland Albemarle County Department of Community Development Regarding: Better Living Berkmar Drive Stormwater Management Dear Mr. Wentland, alio Enclosed are the calculations and details relating to stormwater management for Better Living Berkmar Drive, an industrial and commercial development. Stormwater quality will be primarily addressed through an infiltration tank in the center of the site, with supplemental purchase of off-site nutrient credits as required. Iwo In the pre-development condition, site runoff flows primarily to the north, with a small amount flowing to the south. Post-development, all runoff will be directed to the north, and the infiltration tank will detain peak flows as necessary to comply with the Energy Balance Equation. The one-year post-development outflow from the storm sewer has been eliminated, as the Energy-Balance Equation calls for a 0.018 cfs max flow. The ten-year post-development flow is constrained to below the pre-development level. The 100-year storm is contained within the system. If you have any questions please do not hesitate to contact me at your earliest opportunity. I may be reached at: laurena.shimp-enqineerinq.com or by phone at 434-227-5140 x4. Yours Truly, Lauren Gilroy Shimp Engineering, P.C. PPROVE[ b ii is All emarle C coantymCorri[ { + K, 3i•a lcp rF1rantnateatey1/Pflkrt rir Contents: Pre-Development Pre-Development Drainage Map Pre-Development HydroCAD Report Post-Development Post-Development Drainage Map Post-Development HydroCAD Report VaRRM Report Infiltration Computaitons LD-204 Worksheet LD-229 Worksheet Independent Reports Excerpt from NRCS Soils Report NOAA Precipitation Report MN IMO MO r 1 ..... 1 1 . STp1E ROUTE '1403 2 R DRIVE S r" r'r.'-'. y_„i S_ 11 T-xF / I'/ J` /l 1 x..-- x -x \1 l I//1 E \ I\ \ \\ \ I 1 I . i / x -`' x 11\ \`I I- A A ` I 1 1 II V \\, A `\ cl_ 1 \ A E\\ \. \\E+ 11 II 11 1 I i I V \V \I H I ! I I I E I1 III I I I I 111 I l l 1, 1 II iiiiiilleilihik V I I1II , i1I 1 I V 1\ I e 1 1 1 1 1 I ;I ': I-_,.. 01005,411111111 A w A 1 1 f`I 11 1 1 1 i II i V A >,V A VI•• i I rV I I I I 1 11 ill AI \ V`s\1 < <\ 111 i4 ( V i\ ,E I I I 1 I I i VA\ r p 111 I I r t I 1 I 1}1 (1, M 1° HA V I E/ t F1 I! I tf I/ I it i O • OP I E I l y i l l III VO A MD • f 1E i` IEII IE 1 I I i I I s^ r 1 i 1) 1 1 11 i 1 II i' _\ W E 1 /Elie l j 111 1 : 1 I 1 1 I I I I M 1 _ 1 I IEI I I I , i:, I I I I t E I IEI I i11I'llt I1 111 111,i j 1 2--• 15ilfI. V7::' 11 IL.1 A 11 I\ O I I N ( I i I 1 I r O 11 A I IES 1 1 i i i I r i 1 1 1 1 I r/ / I A =0 I ' 1 1 i I I I 1 i I C/ / 1'i III { 1 I !f // II ( E lye 1 1 I 1 I II r f /ink y a' , I , 1 1 1 I 1 / / l ! 1 I i 11 I i r-* 1 I , / r ; I , E1., 1111 i 1 I I I I 1 ///,'I I I 1 f1 I1 it / NiiI I IE 1 1111111iI11i4.... .E/ 11 1 I 11 11 :I,1/!/ice _ 1 I 1 t f \ 1 '1 d 1 1 1 1 1 1 / l 1z 1 1 1 ' i 11 11 11 11 1 11 II \1 E ' 1 I III 11 1 I 111`( tri I 1 \ ® ....- I, rl / / ( i 1 'i 1, r ,/ / 1 11 i i I I i\\\ I\ I\\ I7i/ ( rk I 1 i r I 1 1 rl i I/ / 1 4 1 \\\\\1\`\\\ ai l / ! 1 f V i yi144 1 E _"`: (\ \\\ 1 A Al\``` 2 r / I I i ti 1 A / r\ 1 v , vv 1 i / , / I I \ J r // ,/ / / 4 //E __-' i r'/, !r I \ i /i l / i 1 I ,'//'/¢/ ( E\\\ I1\.,`\ ' (/ y,, l 1 ff 1 , ,/ i\ \\E \ E i- / I \ \\ \\ \\\ , 11 l Thr'/ .,.,/ I II \. \, \1 / 7 /' MI / I I A 1 1 r i I 1 1\ I r I I \ \ \\ ••\ • J1 l I I 1 \ `\ \111 I tl 1 II I 11 11! 11111 1 1 I' !1 i i { I0 'C Iii/ I 1 1 1 1' 1 1111 F-+ III,\ t I i r.. f i l l f 1 I up v W v 1,\I\ I\ I\\ ii, ,' /,ie.,/' , rr l // 1 1• f m 1 If! i d I 1 11mf X1,,,, , O < O I\\i\1111\\ f,„,/, , ,„ CZ N 'd 1\ I I\\ h tlrlr l / r 2 11 t\\\ \ l i/ i I 0 1 tea' 1 r r. I I , 1 ty 1\ 1-r rr r r1 II 1 7 1. v ."+ imp,1,1 r r r 1 l / 1 o F i Fgg O \\ \,1\\+ Iii, i' i/ '// ' I H .. ,,, ... o. ,' / 7/ 1 / O O11 1 / ID V1 (D V) I , \, TT N 1 1 ) \ l_.l_/ 4 P 0 7/ I/ li I I, - ' L.. / / j'S' IT_ I 9 r) 0 / / / / r I / / / ' ,' ' i 1 ' 0 r / ///, /- ,,I \ m I I /( I/ (/— v V 11 N v vv \ A vA , Z cn cn O I\1 \ \ \.\\\ n D D i' I \ \ I \ 1 lJ 11\ \\\ \\ \ \/ b D Better Living Pre-Development Type 1124-hr Prepared by Shimp Engineering, P.C. Printed 1/19/2017 HydroCAD®9.10 sin 07054 ©2011 HydroCAD Software Solutions LLC Page 1 Summary for Subcatchment 1: P.O.A. 1 Runoff = -@ 12.10 hrs, Volume= S Depth> 0.22" Runoff by SCS TR-20 method, UH=SCS,Time Span=0.00-24.00 hrs, dt=0.01 hrs Type II 24-hr 1yr Rainfall=3.01" Area (sf) CN Description Land Use 79,418 55 Woods,Good, HSG B Woods 15,173 61 >75%Grass cover,Good, HSG B Open Space 94,591 56 Weighted Average 100.00%Pervious Area Tc Length Slope Velocity Capacity Description min) (feet) (ft/ft) (ft/sec)cfs) Direct Entry, Summary for Subcatchment 2: P.O.A. 2 Runoff = _@ 12.08 hrs, Volume= S Depth> 0.20" Runoff by SCS TR-20 method, UH=SCS,Time Span=0.00-24.00 hrs, dt=0.01 hrs Type II 24-hr 1yr Rainfall=3.01" Area (sf) CN Description Land Use 29,874 55 Woods,Good, HSG B Woods 100.00%Pervious Area Tc Length Slope Velocity Capacity Description min) (feet) (ft/ft) (ft/sec)cfs) Direct Entry, Better Living Pre-Development Type 1124-hr Prepared by Shimp Engineering, P.C. Printed 1/19/2017 HydroCAD°9.10 sin 07054 ©2011 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment 1: P.O.A. 1 Runoff = Ia7 12.05 hrs, Volume= 0.236 af, Depth> 1.30" Runoff by SCS TR-20 method, UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 10yr Rainfall=5.50" Area (sf) CN Description Land Use 79,418 55 Woods,Good, HSG B Woods 15,173 61 >75%Grass cover,Good, HSG B Open Space 94,591 56 Weighted Average 94,591 100.00%Pervious Area Tc Length Slope Velocity Capacity Description min) (feet) (ft/ft) (ft/sec)cfs) 12.0 Direct Entry, Summary for Subcatchment 2: P.O.A. 2 Runoff =1.22 cfs @ 12.03 hrs, Volume= 0.071 af, Depth> 1.23" Runoff by SCS TR-20 method, UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 10yr Rainfall=5.50" Area(sf) CN Description Land Use 29,874 55 Woods,Good, HSG B Woods 29,874 100.00% Pervious Area Tc Length Slope Velocity Capacity Description min) (feet) (ft/ft) (ft/sec)cfs) 9.6 Direct Entry, ROUTE 1403 4 STAT E BEPKMAP OPPIE m J 7//-- -- ---- 1' T"74 d4 g/699 SF 1 - I i 1 v 16--,I I i i il1; _ --\4 , ' i01110" V v v p 111 13 . ' III v. V i .. ,) t•` tr 000' 1 I i i A i--, as• II 71 t 8 l'it ::. , ,\ ,,,,,,,,-; , , v , v, ,__ 1,, i ed, ..,4,.. 1, 1 I\ ' c--:7:.:'.. 'D'' 77*P''''..,..• Tt' lM7'.1111E1 ..H r- ---- / 1 '1 . 1 - IF-''''-) I --rr\ g , ,, ,, . ,„, \, , cam. 1 1 1 I f 1 , I it VV J _ _--'..._: -;.--t.:------ lie:i i I f r 1 I ! r r 1 (1 r V i 1I t i///i;! moi/ I / , I/ / \ I) fill fiat/ft, r ) 1 I 1rII1 r 1 I !1 1 / i I IV 1 1 1 , ' - V r r I l i l l / 1 I i I0lyI17vI \ 1 1 1 i l i 1 11 F v I 111N\\. rra II I; v - co, I rr +' i 11 II , '`\ 1\ 1 i I it I 1 \, i!y. 7q III t- 1 „ :1 , 1 I\\•\ i- 1 1 I i I \ I t I I 1 V\A \ \ Tj 11 1 I I 1 I I\\\\\ \\\\\ i it r / 1 i ( I3. L' vv ,, C 7 r / I i 1 7 1 1 1 Q„i I I I1 1 I\ I I\ 7 1 i/) N III N''`\ 1 I I ' L U I!' 1 I - \ 1', 111, 1 \ 11 ! A /w om \ I , 1 11 \1 1 11; I I j I f v 1 I I v w t 1 11\\\` 1`111` r I -- m r o o 11,1`\ i it r1!; 1111 AVAV A 1JJ11 1 1111 1\\\\ t O 7 (////////,J 1 NM 1U rt It,,,/,, 1 4 Il \\ Z 171/r 11 1\, 11\\\\\ \ I L' (!/ !/% / MO I 10 1 C) O vv11 `v 1 vI 1moo, s _. As _ fi(r i 1 I 11 p+•..- 4049.4 II X\' j e . -. lip- INIFAINIFIZ74/21055,41101M, I to11Jr, J, d 1 '1I I 1 ,\I /./ 1-- i.5. ir i l\ 1 1 _- I) 1I\\ I i i 7" ITl 7 1 r ; t_ 22.3 t- 0' / O W i I Cn a v m • fTl I 22.4:r*-1 r/I lit/l 1// /' i' A 1 Vvv; S En 1_ I l r! rr It i 1 / II Fri CD I I t I ! r v OOOOOO1- 11II i r1 i i II vv v 1 11 w 1 \ \ \ 1 1 1 \ \ )1 NO 0o j O O i/ 1 \ \ \ \ \ VC Z 1 1 I 1.11 n 1 Fri D o nil A \\ \ I 1 \\ A 11 vI 2N C C1 on CD 1 1 \ \ ZI t- A 1 A , \ V A \ K Drr-r 1 ,\ I I I I V y-• I 73 /U 1 1 1 1 1 1 `.. I 0---------...„... b, c\ 1 West DA 4 Q---- East DA Infiltration Detention t r____I Subcat Reach!on.Link Drainage Diagram for Better Living Post-Development Prepared by Shimp Engineering, P.C., Printed 1/19/2017 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Better Living Post-Development Type 1124-h Prepared by Shimp Engineering, P.C. Printed 1/19/2017 HydroCAD®9.10 sin 07054 ©2011 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment 1: East DA Runoff =4.86 cfs @ 11.96 hrs, Volume= S Depth> 1.99" Runoff by SCS TR-20 method, UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 1yr Rainfall=3.01" Area (sf) CN Description Land Use 59,281 el Roadway 100.00%Pervious Area Tc Length Slope Velocity Capacity Description min) (feet) (ft/ft) (ft/sec)cfs) Direct Entry, Summary for Pond 2: Detention Inflow Area=1.361 ac, 0.00% Impervious, Inflow Depth> 1.99" for 1yr event Inflow =4.86 cfs @ 11.96 hrs, Volume= 0.226 af Outflow =4.76 cfs @ 11.97 hrs, Volume= 0.225 af, Atten=2%, Lag=0.8 min Primary =4.76 cfs @ 11.97 hrs, Volume= 0.225 af Routing by Dyn-Stor-Ind method,Time Span=0.00-24.00 hrs, dt=0.01 hrs @ 11.97 hrs Surf.Area=485 sf Storage= 197 cf Plug-Flow detention time= 1.6 min calculated for 0.225 af(100%of inflow) Center-of-Mass det.time=0.3 min (804.9-804.6) Volume Invert Avail.Storage Storage Description 1 4,065 cf Device Routing Invert Outlet Devices 1 Primary 501.50' C=0.600 2 Primary 503.90' Cv=2.62(C=3.28) Head (feet) 0.00 0.80 1.60 Width (feet) 3.92 3.20 0.00 Primary OutFlow Max=4.76 cfs @ 11.97 hrs HW=502.49' TW=500.00' (Dynamic Tailwater) E1=Orifice (Orifice Controls 4.76 cfs @ 3.39 fps) 2=100-yr Weir#3 (Controls 0.00 cfs) Summary for Subcatchment 3: West DA Runoff =5.36 cfs @ 11.96 hrs, Volume= S Depth> 1.99" Runoff by SCS TR-20 method, UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 1yr Rainfall=3.01" Better Living Post-Development Type l/24-hr Prepared by Shimp Engineering, P.C. Printed 1/19/2017 w. HydroCAD°9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 3 Area(sf) CN Description Land Use 65,309 • Roadway 100.00%Pervious Area Tc Length Slope Velocity Capacity Description min) (feet) (ft/ft) (ft/sec)cfs) ai Direct Entry, Summary for Pond 4: Infiltration Inflow Area=2.860 ac, 0.00% Impervious, Inflow Depth> 1.99" for 1yr event Inflow = 10.08 cfs @ 11.97 hrs, Volume= 0.474 af Outflow =0.11 cfs @ 10.73 hrs, Volume= 0.147 af, Atten=99%, Lag=0.0 min Discarded =0.11 cfs @ 10.73 hrs, Volume= 0.147 af Primary =0.00 cfs @ 0.00 hrs, Volume= 0.000 af Routing by Dyn-Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs @ 19.57 hrs Surf.Area=5,418 sf Storage= 14,500 cf Plug-Flow detention time= (not calculated:outflow precedes inflow) Center-of-Mass det.time= 160.8 min (965.5-804.7) Volume Invert Avail.Storage Storage Description 1 497.50' 11,909 cf 43,344 cf Overall -13,572 cf Embedded =29,772 cf x 40.0%Voids 2 498.50' 13,572 cf IIIMIIMEMMEEMMINIMME 25,481 cf Total Available Storage Device Routing Invert Outlet Devices 1 Discarded 497.50' gIIIIMIMIIIIIIMINIIIMlIlm 2 Primary 497.50'L=97.9' Ke=0.300 Inlet/Outlet Invert=497.50'/485.00' S=0.1277 '/' Cc=0.900 n=0.011 3 Device 2 502.10' C=0.600 4 Device 2 503.90' -S Cv=2.62(C=3.28) Head (feet) 0.00 0.75 1.50 Width (feet) 5.75 4.33 0.00 5 Device 2 503.90' Cv=2.62(C=3.28) Head (feet) 0.00 0.75 1.50 Width (feet) 5.75 4.33 0.00 Discarded OutFlow Max=0.11 cfs @ 10.73 hrs HW=497.58' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.11 cfs) IMIIIIIMEMINIME@ 0.00 hrs HW=497.50' (Free Discharge) 2=STM 3-4 (Controls 0.00 cfs) 3=10-yr Orifice (Controls 0.00 cfs) 4=100-yr Weir#1 (Controls 0.00 cfs) 5=100-yr Weir#2 (Controls 0.00 cfs) Better Living Post-Development Type 1124-hr Prepared by Shimp Engineering, P.C. Printed 1/19/2017 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 4 Summary for Subcatchment 1: East DA Runoff = 10.13 cfs @ 11.96 hrs, Volume= 0.494 af, Depth> 4.36" Runoff by SCS TR-20 method, UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 10yr Rainfall=5.50" Area (sf) CN Description Land Use 59,281 90 1-yr Adjusted CN Roadway 59,281 100.00%Pervious Area Tc Length Slope Velocity Capacity Description min) (feet) (ft/ft) (ft/sec)cfs) 5.0 Direct Entry, Summary for Pond 2: Detention Inflow Area=1.361 ac, 0.00% Impervious, Inflow Depth> 4.36" for 10yr event Inflow = 10.13 cfs @ 11.96 hrs, Volume= 0.494 af Outflow =9.09 cfs @ 11.95 hrs, Volume= 0.492 af, Atten=10%, Lag=0.0 min Primary =9.09 cfs @ 11.95 hrs, Volume= 0.492 af Routing by Dyn-Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs @ 12.13 hrs Surf.Area=1,211 sf Storage= 1,401 cf Plug-Flow detention time= 6.2 min calculated for 0.492 af(100%of inflow) Center-of-Mass det.time=4.0 min (786.7-782.7) Volume Invert Avail.Storage Storage Description 1 501.50' 4,065 cf 48.0" D x 323.5'L Pipe Storage S=0.0050'/' Device Routing Invert Outlet Devices 1 Primary 501.50' 21.0"Vert.Orifice C=0.600 2 Primary 503.90' 100-yr Weir#3,Cv=2.62(C=3.28) Head (feet) 0.00 0.80 1.60 Width(feet) 3.92 3.20 0.00 Primary OutFlow Max=8.04 cfs @ 11.95 hrs HW=502.99' TW=502.41' (Dynamic Tailwater) AL1=Orifice (Orifice Controls 8.04 cfs @ 3.67 fps) 2=100-yr Weir#3 (Controls 0.00 cfs) Summary for Subcatchment 3: West DA Runoff = 11.16 cfs @ 11.96 hrs, Volume= 0.544 af, Depth> 4.36" Runoff by SCS TR-20 method, UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 10yr Rainfall=5.50" Better Living Post-Development Type 1124-hr Prepared by Shimp Engineering, P.C. Printed 1/19/2017 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 5 Area (sf) CN Description Land Use 65,309 90 1-yr Adjusted CN Roadway 65,309 100.00%Pervious Area Tc Length Slope Velocity Capacity Description min) (feet) (ft/ft) (ft/sec)cfs) 5.0 Direct Entry, Summary for Pond 4: Infiltration Inflow Area =2.860 ac, 0.00% Impervious, Inflow Depth> 4.35" for 10yr event Inflow = 20.17 cfs @ 11.95 hrs, Volume= 1.037 af Outflow =3.56 cfs @ 12.12 hrs, Volume= 0.685 af, Atten=82%, Lag=10.4 min Discarded =0.11 cfs @ 8.25 hrs, Volume= 0.175 af Primary =3.44 cfs @ 12.12 hrs, Volume= 0.511 af Routing by Dyn-Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs 11111111M@ 12.12 hrs Surf.Area=5,418 sf Storage=21,199 cf Plug-Flow detention time= (not calculated:outflow precedes inflow) Center-of-Mass det.time= 68.6 min(853.2-784.6) Volume Invert Avail.Storage Storage Description 1 497.50' 11,909 cf 43.00'W x 126.00'1 x 8.00'H Gravel 43,344 cf Overall -13,572 cf Embedded =29,772 cf x 40.0%Voids 2 498.50' 13,572 cf 72.0" D x 120.0'1 Pipe Storage x 4 Inside#1 25,481 cf Total Available Storage Device Routing Invert Outlet Devices 1 Discarded 497.50' 0.900 in/hr Exfiltration over Horizontal area 2 Primary 497.50' 18.0" Round STM 3-4 L=97.9' Ke=0.300 Inlet/Outlet Invert=497.50'/485.00' S=0.1277 '/' Cc=0.900 n=0.011 3 Device 2 502.10' 17.0"W x 5.0" H Vert. 10-yr Orifice C=0.600 4 Device 2 503.90' 100-yr Weir#1,Cv=2.62(C=3.28) Head (feet) 0.00 0.75 1.50 Width (feet) 5.75 4.33 0.00 5 Device 2 503.90' 100-yr Weir#2,Cv=2.62(C=3.28) Head(feet) 0.00 0.75 1.50 Width (feet) 5.75 4.33 0.00 Discarded OutFlow Max=0.11 cfs @ 8.25 hrs HW=497.58' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.11 cfs) 1111.11111111=11111.@ 12.12 hrs HW=503.78' (Free Discharge) STM 3-4 (Passes 3.44 cfs of 23.09 cfs potential flow) 3=10-yr Orifice (Orifice Controls 3.44 cfs @ 5.84 fps) 4=100-yr Weir#1 (Controls 0.00 cfs) 5=100-yr Weir#2 (Controls 0.00 cfs) Better Living Post-Development Type 24-hMIIIMIIMOD Prepared by Shimp Engineering, P.C. Printed 1/19/2017 HydroCAD°9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 6 Summary for Pond 2: Detention Inflow Area=1.361 ac, 0.00% Impervious, Inflow Depth> 7.80" for 100yr event Inflow = 17.44 cfs @ 11.96 hrs, Volume= 0.885 af Outflow = 14.07 cfs @ 11.95 hrs, Volume= 0.883 af, Atten= 19%, Lag=0.0 min Primary = 14.07 cfs @ 11.95 hrs, Volume= 0.883 af Routing by Dyn-Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs 12.02 hrs Surf.Area=872 sf Storage=3,515 cf Plug-Flow detention time= 5.9 min calculated for 0.883 af(100%of inflow) Center-of-Mass det.time=4.4 min (771.8-767.4) Volume Invert Avail.Storage Storage Description 1 501.50' 4,065 cf 48.0" D x 323.5'L Pipe Storage 5=0.0050'I' Device Routing Invert Outlet Devices 1 Primary 501.50' 21.0"Vert.Orifice C=0.600 2 Primary 503.90' 100-yr Weir#3,Cv=2.62(C=3.28) Head (feet) 0.00 0.80 1.60 Width (feet) 3.92 3.20 0.00 Primary OutFlow Max=9.69 cfs @ 11.95 hrs HW=505.06' TW=504.96' (Dynamic Tailwater) t1=Orifice (Orifice Controls 3.78 cfs @ 1.57 fps) 2=100-yr Weir#3 (Weir Controls 5.90 cfs @ 1.58 fps) Summary for Pond 4: Infiltration Inflow Area=2.860 ac, 0.00% Impervious, Inflow Depth> 7.80" for 100yr event Inflow = 33.26 cfs @ 11.95 hrs, Volume= 1.858 af Outflow = 26.48 cfs @ 12.01 hrs, Volume= 1.502 af, Atten=20%, Lag=3.5 min Discarded =0.11 cfs @ 5.37 hrs, Volume= 0.194 af Primary = 26.37 cfs @ 12.01 hrs, Volume= 1.308 af Routing by Dyn-Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs @ 12.01 hrs Surf.Area=5,418 sf Storage=25,402 cf Plug-Flow detention time= (not calculated:outflow precedes inflow) Center-of-Mass det.time= 49.7 min (819.1-769.5) Volume Invert Avail.Storage Storage Description 1 497.50' 11,909 cf 43.00'W x 126.00'1 x 8.00'H Gravel 43,344 cf Overall -13,572 cf Embedded =29,772 cf x 40.0%Voids 2 498.50' 13,572 cf 72.0" D x 120.0'1 Pipe Storage x 4 Inside#1 25,481 cf Total Available Storage Better Living Post-Development Type 1124-hr Prepared by Shimp Engineering, P.C. Printed 1/19/2017 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 7 Device Routing Invert Outlet Devices 1 Discarded 497.50' 0.900 in/hr Exfiltration over Horizontal area 2 Primary 497.50' 18.0" Round STM 3-4 L=97.9' Ke=0.300 Inlet/Outlet Invert=497.50'/485.00' S=0.1277 '/' Cc=0.900 n=0.011 3 Device 2 502.10' 17.0"W x 5.0" H Vert. 10-yr Orifice C=0.600 4 Device 2 503.90' 100-yr Weir#1,Cv=2.62(C=3.28) Head (feet) 0.00 0.75 1.50 Width (feet) 5.75 4.33 0.00 5 Device 2 503.90' 100-yr Weir#2,Cv=2.62(C=3.28) Head (feet) 0.00 0.75 1.50 Width (feet) 5.75 4.33 0.00 Discarded OutFlow Max=0.11 cfs @ 5.37 hrs HW=497.58' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.11 cfs) Primary OutFlow Max=26.36 cfs @ 12.01 hrs HW=505.46' (Free Discharge) t2=STM 3-4 (Inlet Controls 26.36 cfs @ 14.92 fps) 3=10-yr Orifice (Passes<5.05 cfs potential flow) 4=100-yr Weir#1 (Passes<26.17 cfs potential flow) 5=100-yr Weir#2 (Passes<26.17 cfs potential flow) w i I 1 1 I 1 1 1 i 1 I i I I 1 0 o 1 1- o co m O 3 1 1 1 tc o m m , I O N o O O O N 1 t- O 1 o n IL 2 C c 1 a o z O O O o I E IX 0 C I cii O M S c 1 ea O V w m 1 42 O O OwO O tmNGinGJVc ro 0 o N CO o O N I E d O IJ ia. a I E a o 1 cr, l0 .-IN N 00 DD ' Tu p O o O O W o Lr' O cc O V co G Q O O O O c.,"- V1 V N N I CI M d 1 N Zh 0 I O -+ 0r T TTJ v o a a o A ar Iv- L i a v d) c Z Lj ~ 1.3 Lc v c E a c E m a a E I CC a E c E v c c n N cm E O - O 3 z O O O O O L U v1 E v I c o v Ea a v E a. v v cc O f9 m f6 A O l J O j > 'p f6 > V 'O O m E 'p' c a 7, o co c a = ° E c 3 ° m co O\ t v v -0 a p a Z c vi J f E t! H 1- c I 75 C OC7vavca m m m ?E in n ° in v, r- O. I- I- V o - o a) C CC `. 1 To le O N 1O 00 TooJ0O - F o o N n) 12 m ry a) o 0 0 0 0 0 Q 0 0 0 o Q o 0 Y O O O O O 0 O O o o0r t c o a o O 0 v Q O O O O Q O O E or y 0 O O O O 0 O O E e 0 CC3 9. Mali— m 5 U 0 0 0 0 0 0 0 a o 0 0 0 a o o 6 0 0 0 0 6 0 0 a m CO 0 0 0 0 0 0 Q 0 0 0 o Q 0 0 r, 00000 000 An ao m m Lo a N QO N tO CO Q t. 0GOOniNGrirnN L CoEE 7 ow N 0)V E ro L E r E II H y cOa s0) u U u a4i n v 0 ud0.1 CI C U 70amaaCVv o aCO ooa > Q2N0) C ao o J i o.H FZ- a) E m p o a a CoOa+ d E Eoisw O a) IL- 017c c _ @ > E '" o -0 N K "" aF- o To d O EN 1- o 00 E t.D 0 N .0 m K Cl.I- 0aO .-.o -0o. a a) To o m m Lo i- o c o o N C co a - 00 O O N N d u vjI- 8 O 02 v 0- 5 y0 O D sN 2 c cE n a O O E j O O O O 4"" y ` O c0 O O O O a 01 O E 0 0 0 a . ., o•E CC 0 J Q U C o F- a cnCC mc N o E c H o O o a, n O o O v M V o O O I- > N a o m m v m O to 0 O O N l0 3 Q G) N mO O N 5 =p a, ON1 N N Nua N E 3 0 CO F- `1 NNO0OaQ m m N0000OJ r. LU ,10 ,. 0 N l000 Q O O O A -p ry O N O (-6 NC `1 N g V O Q Q en v CC Fe iAv -O ad T v a > CUdN7d co v L L E u H u Q Q v C a O O V > u O O jQNNda tr o E u a AV v aHa6J d 7E a w O C c O C C Q N c 7 V O 5 d a aA 41 clJ Q ~ Y i N Q O 0 00 O aO 4J a 6 >y E a 2 c V Yco >H H H J C d to 0 o > 0(0 o 2 o 0 o a o sp2co MOO I I WS I I I I I I 4/111 I I r I I I I m I a, Q o 0 0 0 0 0 O O O O O O O O o O O 0 0 0 0 0 0 AIN I IIo I 0 CO r I a I Q o 0 0 0 0 0 tal O 0 0 0 0 0 0 0 0 0 0 Y I 0 0 0 0 0 0 0 oc I m 0 0 I Iii V c I m a o Z V Q O O O O O O a1 000000 E mom y A O O O O O O E CC I c n O t0 S I o rcrc co C I E a OIa1 I O Q O O O O O O ifl a! 0 0 O O O O O O O O O III : 111 : : c_ RoQvTA lD a! Q 1 V O , o l0 0 Ql V r. I f`a m m iry m ry v v c I N o I C c c 7''c AN I L o v Z 3 3 3 3 . II i I v om z 3 3 °3 3 z 3 3 zIVU 11 K C C > C G I I0 Y I1-3 3 auvo Im 0 m y i a Iv Q c c 0 _`. m Z w 5 5 I o m z iiii co c c_ cuIN a 0 v t w O ai I— ra N O 0 c I WI z I m C m 7 H I Better Living Berkmar Drive Infiltration Computations Design Data Infiltration Test Results From HydroCAD B-1 B-2 B-3 Bottom 497.5 2.518 0.665 0.428 Top 500.7 2.138 0.428 0.333 Height 3.2 2.043 0.475 0.285 Area 5418 2.091 0.38 0.285 Volume 17338 2.043 0.38 0.276 Storage 0.38 0.285 9641 per VRRM req.) Averages Porosity 2.167 0.451 0.315 0.56 Computed) 0.978 d _ (1/2fXtd) max — r7X12) f = measured infiltration rate (in/hr) 0.9 td = maximum drawdown time 48 r] = porosity of the reservoir 0.56 d max = maximum depth of the infiltration practice (feet) 3.24 O i Structure co rn Number 0 0 0 0 0 N Inlet Type CO CO W CO CO uw Curb Opening 0 0 0 -- ia Catchment Area o O o Co - Co 0' Runoff Coef cT W A 0 0 0 r iv o, o CA Cn W N O cn JJ J COIntensitydiov, o cn o 3 o O N c0 O 0o A J — -i l0 Q CatchmentCOCS) W CO O O A O 5 CD n n Q carryover 0 0 A N 0 CO 600 INJ 01 U) co (3) w w Q Tota I N o co o o 0 0 0 0 0 O 0 0 0 0 6N Mannings N 0) 0) 0) 0) 0) 0) 0 0 O 0 0 0 w Gutter Slopew U, O w O 0 0 N N w ", Pave X-slope O co Gutter X-slope Total Gutter O1 Spread Depth at Curb m in 0 oo Efficency 0 CD O Q intercepted BypassedQ 0 0 0 0 0 0 — iv N v Midpoint Depth c.31- NOcO 01 c0 0 0 0 0 o 0 N Curb Height oro CD 0 0 0 0 0 0 0 W W N N :N D/H a c0 -' 01 O CO c0 7 - - N) CO 01 — Midpoint Midpoint 1,1 o a) w v V.J N Cr, C o Spread I 11110 77 T0O 3 1-, NJ W A cm I 00 I-, ' Y H O m v X 1--+ N) W Ul 0l -I LO N O I-, v D n C n 0 0 0 0 n v iv i—, Lo W Ln Co U1 I-, C.") 0 c 0 0 0 0 o co 00 J 00 •p A CO W 1.11 n n O O O O Ql N 1-, N Ul W In F, Ql 7 n O O O O 2 l0 W - N a) 3 l0 Cr) I--, al 3 i- n 0 r U'I U'I U'1 U"1 5' A i, o O v — v00 I N H N 5 o CD a) rn a) a) = rn 00 0o CO 00 OJCT) I-, I-, C, m = n rn - r- D h oACT) N) O I-, "-- o <•• O A 01 A I 60 L Q OA1-, N 01 O 03 G CDCD m - c ; m A A A In Ln Ln U i U-1 0 3 CO 13 6Ti v 0 0 0 0 0f v 3 W o in o -I o 0 0 0 o 00 0 0 0 0 0 0 0 A A A A A Ln Ln Ul U1 CO OCOO QOi 1-' 11 WW N I Ul l0 N O --' a. 0 0 0 0 0 0 0 0 O O r -0N 0 W rn CT) U-I ALD CD I-, 00 J J F, 0 J f-, 1..., Ql CO l0 Ul 0 I-, l0 N co I-, W I- Cf") 00LDLO o N E A ,...4 F, N W .l:::.W N 1 W lD W U"1 I • U.) - In N N U'1 00 l0 CO W Lri 0 0 \ o 0 0 3, D N I-+ F-, F, I-, I-, F-, F, F, Ui Ui Ul Ul U'1 Ui U-1 Ui A n n v 0 fD V N F, I- I-, en I N N Ui ro 1 0 )11 01 - O F, Cl O LO U'1 lD Ci T_3. n O 5 0 0 O O F-' W F-, 1-, J 3 Ui N I 0 z RI r NC N M OL£6TZ4 OTE6TZ4 05Z6TZ4 06T6TZ4 0£T6TZ4 OL06TZ4 OT06TZ4 M AS LZ 08L M„85 LZ o8L K A coN m v' t. P 1,3. ..,.,. ,, „:„..:.,,,„:„., ,,,,,.,z,„,„..„:„.„..„.„, ....,,s .,..... i.:-./. Q rk L r N gg a) 1 U m N y, f't73 N V/ N ZgErz CO `3,, r;,", '' V, CDU4NCO NN r. a 0 N i O. in 0 7 NN 03x ra117.10rert. "''o 8 E N a N a s v sN} it I: .t„ o'A..'ff.. o ,-.i. o a M„bZ.az 08L I411P11 M„bZ,BZ o9C OLE6TZb OT£6TZ4 OSZ6TZ4 06T6TZ4 0£T6TZ4 OL06TZ4 OT06TZ4 h z z v N n M wan Am w o 0) c. o c» O . Coc cco fO tcAN 'ONN a N coN N m W N 73 (f)7 aO c6oNU00 Co3cUCcc) N Co 7 o115VCLomo •cUv ai j cE co 7 N o N N NQ U p C Uja coCL CD 0 N 0NZCON o ) . Q Co 2 o UapCDC C) N w N a Co (/) EO O N ca QCaN Qaca m — a CD mC N °m Uz 7 a) E 73 aCo A f Za Z 2)N- rENQ3NLDE0QC7aa) x7 p a) CoOQCa) 'n (6 co Qcu a3 UNW NO Co 06 ) t U U o_ Q y Ce 7 '0 COCo Ua ° L3 N p N0 N woa) QN O N Q "6 vQ Qo > a) 0c 7v mw U o co ca0CLZDOCoa) CC .-, s 7 Co U 'p Co 2 a) ca 0 Q Co S] a) aQOO - O C C a) 0 a) U) a) a) 0 E ` N N O N tp E C a) o Cl) 0 m > — .o Q `o v o 0 o a .0 m EQ. O > . tp.. - 6 a) Co _ 7 O m U a) a) 2 a) N Q... Q U m Co cA J N N a C U ca O) Q > N Co L N E Q co D Q o co 2 Q 0 ca o c ` m — a) o 0 CoCLa)asCOEmE -CaC s m12 rn iu :° C <° oo amia J, 0 =p C -O C N - N + N U E w aS N Co CoNQCo O "O cz 7 0 .O c N ~ O ° C c9 -C U c 0 'p6 < CO ` 0) N t C °-_o Co Cl) m % • E 'C ci)— EC o o aim C a) om73c O) aEi a) a) Co Cl) o .o c o ° a) aai o o .N Z < Q • c° s -0 7 N ` 2 N w. N N U U1 - 6 N U C i Q a) cn a) E N p 'Q a) as a) 0 7 U CO a3 N 7 p Q. N U N > — — Co w N O) c ns C .N N '0 a) N p O p ca O N -a is t a) O 7 O Co / 0 L E ca E H W E QN a E U) O a'6 < O i_ _c v) U) to `o oN f- ( o) - o 0 0. a) a) 7 0 CO a) o) o CO 20 CO C 7 N T C ca C co a O a U m U) U a) V cmN N O r Co O C C ca N a1 c a O O N a O O J N a, N O O r Q CO CO O" )Cl E co p , a C U1 U) U Co N m a' 0 N co U) U) > 5 0V U) O a' c D 2 J N CO R C r Q a) ' 7 W a o ¢ cIIL d , ° 0. I 1 Y C111 U' 1— m W J N a c Q O .N-•0. 0.0 aai .c o Co CO CC 17, o co E Na . .. . N aCo ZCo7 d 0wCCC `Co 0 O — dN CDD07 .. m ... ON ' 7 VO — N 0O. d O. a a O a a 7 T a) NQNcaca i T a) C a , _2 2 2 cO SO o a) N — t C as a i a OdQ -(7) C p ` aO 2N C caCN W 0 TO as > CO Q CO CO CO 'om m oo 0 0 JJ 2 .2 .2 0- a CO CO CO (7 (7CO a) a c of X 4 13 U1 Q N Custom Soil Resource Report Map Unit Legend Albemarle County,Virginia(VA003) Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 27B Elioak loam,2 to 7 percent 1.8 8.2% slopes 27C Elioak loam,7 to 15 percent 10.5 48.7% slopes 34C Glenelg loam,7 to 15 percent 0.7 3.4% slopes 34D Glenelg loam, 15 to 25 percent 2.3 10.6% slopes 39D Hazel loam, 15 to 25 percent 1.6 7.3% slopes 88 Udorthents, loamy 4.0 18.4% 93D Watt channery silt loam, 15 to 25 0.7 3.4% percent slopes Totals for Area of Interest 21.5 100.0% 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 contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been 10 NOAA Atlas 14, Volume 2, Version 3 F Location name: Charlottesville,Virginia, USA* '"-"'` aIX t Latitude: 38.0957°, Longitude: -78.4686° nOil Elevation:492.59 ft** source:ESRI Maps v-* Tsource: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 II II Average recurrence interval (years) Duration 1 I 2 I 5 L 10 25 50 100 200 L 500 IL 1000 0.351 ( 0.419 0.492 0.553 0.623 0.678 0.7290.778 0.837 0.8855-min ( 0.317-0.390).(0.378-0.465) (0.443-0.545)(0.497-0.612) (0.557-0.687),(0.604-0.747) (0.646-0.803)I(0.684-0.857) (0.728-0.925) (0.763-0.982) ag NO0.561 0.670 I 0.788 0.884 0.993 1.08 I 1.16 1.23 1.32 1.3910-min (0.506-0.622) (0.605-0.744)(0.710-0.872) (0.795-0.978) (0.888-1.10) [(0.961-1.19) (1.03-1.28) (1.08-1.36) L(1.15-1.46) (1.20-1.55) 0.701 0.842 0.996 1.12 1.26 1.371.46 1.56 1.67 1.75 15-min ( 0.632-0.778) (0.760-0.935) (0.898-1.10) (1.00-1.24) (1.13-1.39) (1.22-1.51) I (1.30-1.61)1.37-1.72) (1.45-1.84) (1.51-1.94) 0.962 1.16 1.42 1.62 1 1.86 2.06 2.24 2.42 2.65 2.83 30-min ( 0.867-1.07) (1.05-1.29) I (1.27-1.57) (1.46-1.79) (1.67-2.06) (1.83-2.27) l(1.99-2.47) (2.13-2.67) (2.31-2.93) (2.44-3.14) 1.20 t46 1.81 2.11 2.48 2.79 3.09 3.40 3.81 4.1460-minLE1.08-1.33) (1.32-1.62) (1.64-2.01) (1.90 2.33 2.22 2.74) (2.48 3.07) (2.74 3.40) (2.99 3.74) (3.31 4.21) (3.57 4.59) 1.44 1.75 2.19 2.57 3.07 3.48 3.91 4.36 4.98 III 5.50 2-hr ( 1.27-1.64) (1.54-1.99) (1.93-2.49) (2.27-2.91) (2.68-3.47) (3.03-3.93) (338-4.41) (3.74-4.91) (4.22-5.62) (4.62-6.23) I IL . 1.58 1.91 2.39 2.81 ( 3.35 3.81 4.28 I 4.77 5.46 6.053-hr ( 1.39-1.81) (1.68-2.19)2.10-2.75) (2.45 3.21) (2.91-3.82) (3.29-4.33) (3.67-4.87) I (4._____3) (4.59 6.23) (5.03-6.90) 2.01 243 3.02 3.55 4.27 4.90 5.56 6.27 7.29 8.19 z 6 r ( 1.78-2.28) (2.15-2.75) (2.66-3.42) (3.11-4.02) (3.72-4.82) L(4.24-5.52) (4.76-6.26) (5.32-7.07) (6.09-8.23) [(6.75-9.26) 12-hr I 2.52 i 3.04 3.80 4.49 5.46 6.33 7.27 8.31 9.84 11.2 f (2.23-2.89) (2.69-3.48) (3.34-4.34) (3.94-5.12) (4.75-6.21) (5.45-7.19) (6.18-8.25) (6.97-9.41) (8.10-11.2) L(9.08-12.8) I 24-hr 01 3.64 4.65 5.50 6.75 7.83 10.3 12.3 14.0 88 , (3.27-4.09) (4.16-5.22)4.91-6.15) (5.99 7.54) (6.89-8.72) I (8.91-11.5) (10.4-13.6) (11.7-15.5) 2-da 3.55 4.30 5.46 6.43 7.82 8.98 ( 10.3 I 11.6 13.6 15.3 y (3.19-3.96) (3.87-4.81) (4.90-6.10) (5.74-7..161 (6.94-8.69) (7.92-9.97) (8.96-11.4) (10.1-12.9) (11:7-15.2) (13.0-17.1) i 3.78 4.58 5.81 6.83 8.31 9.54 10.9 12.3 1 14.4 16.23-day I (3.43-4.19) (4.15-5.07) (5.27-6.44) (6.17-7.55) (7.46-9.17) (8.51-10.5) (9.63-12.0) (10.8-13.6) (12.5-16.000 (13.9-18.0) 4- day4.01 4.86 6.16 7.24 8.79 10.1 11.5 13.0 15.2 17.1 i 3.67-4.42) (4.44-5.34) (5.63-6.78) (6.60-7.95) (7.98-9.65) (9.11-11.1) (10.3-12.6) (11.6-14.3) (13.4-16.8) (14.9-18.9)it 7-day 4.66 j 5.61 7.01 8.16 9.81 ( 11.2 12.7 14.2 16.5 18.4 4.27-5.09) (5.15-6.13) (6.42-7.66) (7.46-8.91) (8.92-10 7) (10.1-12.2) (11.4-13.8) (12.7-15.6) J (14.5-18.1) (16.0-20.2) I.10-day 5.29 6.34 7.83 ( 9.04 10.7 12.1 13.6 15.1 17.3 19.1 4.87-5.73) (5.85-6.87) (7.21-8.48) (8.30-9.78) (9.83-11 6) l ( 11.0-13.1) (12.3-14.7) L(13.6-16.4) (15.4-18.9) (16.9-20.9) 20-day 6.94 8.28 10.0 ! 11.3 13.2 I 14.6 16.1 17.6 19.6 21.2 I 6.49-7.44) (7.75-8.87) (9.34-10.7) (10.6-12.2) (12.3-14.1) (13.5-15.7) (14.9-17.3) (16.2-18.9) (17.9-21.2) (19.2-22.9) 30- day8.51 10.1 ! 11.9 13.3 15.2 16.6 17.9 19.2 21.0 22.3 8.01-9.08) (9.50-10.8) (11.2-12.7) (12.5-14.2) (14.2-16.2) I 15.5-17.6) (16.7-19.1) (17.9-20.5) (19.4-22.5) (20.5-23.9) 45-day 10.6 I 12.6 14.7 16.3 18.3 19.8 21.2 22.6 l 24.4 25.8 10.0-11.3) (11.8-13.3) (13.8-15.5) (15.3-17.2) (17.2-19.4) (18.6-21.0) (19.9-22.5) (21.1-24.0) 22.7-26.0) (23 8-27.5) 60-cla 12.5 14.7 16.9 18.6 J 20.8 22.4 ( 23.9 25.3 27.1 28.4 y t ( 11.8-13.2) (13.9-15.5) (16.0-17.9) (17.6-19.7) (19.6-21.9) (21.1-23.6) (22.4-25.2) (23.7-26.8) (25.3-28.7) (26.5-30.2) i 1 Precipitation frequency(PF)estimates in this table are based on frequency analysis of partial duration series(PDS). I ll' 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 dill I