Loading...
The URL can be used to link to this page
Your browser does not support the video tag.
Home
My WebLink
About
WPO201400074 Calculations 2015-01-20
SHIMP PROJECT MANAGEMENT CIVIL ENGINEERING LAND PLANNING ENGINEERING January 20, 2015 Mr. Glenn Brooks, P.E. County Engineer Albemarle County Regarding: Riverside Village Stormwater Management Dear Mr. Brooks, Enclosed are the calculations and details relating to stormwater quantity and quality for the proposed development Riverside Village. For stormwater volume, the point of discharge that includes all post- development flow was analyzed to confirm that post-development flows were reduced from the pre- development condition. Required detention was achieved with an infiltration trench, bio-filters,and a �.. detention pipe. Layout and details for the proposed systems can be found on the attached WPO review plans. Summary Table for project outflows: 2-yr 10-yr Pre-Development 9.45 29.20 Post-Development 9.13 29.08 Stormwater quality is addressed with two biofilters and an infiltration trench. If you have any questions please do not hesitate to contact me at your earliest opportunity. I may be reached at: Justin@shimp-engineerinb.com or by phone at 434-953-6116. Yours Truly Op Justin Shimp, P.E. gr` STIN M. SHIM? Lit.Ng.45183 122Jk �- SsIONAI Page 1 of 53 mil Mb Contents: Pre-Development Stormwater Management Calculations: Pre-Development Drainage Map Pre-Development HydroCAD Analysis Post-Development Stormwater Management Calculations: Post-Development Drainage Map Post-Development HydroCAD Analysis Stormwater Quality Calculations: . Water Quality Map VSWMH Worksheet 5D1 VSWMH Worksheet 5D2 . Boring Location Map BMP D Stage-Storage Table from HydroCAD .. Storm Sewer Calculations: Storm Inlet Drainage Map VDOT LD-204 .. VDOT LD-229 VDOT LD-268 VDOT LD-347 Independent Reports: Excerpt from NRCS Soils Report . NOAA Precipitation Report .• .. 4. Page 2 of 53 ma Pre-Development Stormwater Management Calculations Pre-Development Drainage Map Pre-Development HydroCAD Analysis .. .. .. Page 3 of 53 r. Load V `..... l... lira V INA r.- ...i r....3 6.111 w ...i ;.....i7 .....1i u...7 imal sn PA c) r\) \\ % , 4,\;,,,,e\� i� • "��� �� \\ A N o ff,;, / ***y )),v v , / \ ,-;;;, // / n//// (_li' Ak- N \ I :/,i/ / / „, '; F)) --/) / k r C/ . 1 ''-.>. ' ° 1 °' ; ;•%101tt/'(Afr •■ / '/ Z/ i n(/ /1, / - ,,P;i \ \A I !- , II/ /11f0, -' 74_,/ /' _/</Y/ k7 <-1-'L ' 'N‘‘ \\\ \ \\. '-'' 1 , -='-'11 - /7- -/ /%7 /f ■ t•co- '-\ \\ \ < - 1,! , /›- j‘ K--/‘ l'--- -A ‹l' / It' ■■\V \ a O it -'• / � • ` 0 4 iiii\it 1 VC; � .� �` 1/4 �.✓ , II I - ik '-' / , \ \\ p ii 1/ i /'y z/- A ,..-7,,,-,K--/'' , ,-/.....-_7L-.,,.... / - *,‘ N 1 \ 1 �, u 1 iI -� X15\ ��? / - le, , \ \ ` Q, 41 \ -1 1 JI Imo/ /? (/� � = / /��, I /`� \/�, \tii, > / /� \ , IL/,,,/ \ j< i /--..1. ____.--"" . r!/NP</ 7,,</ //Clk/‘ /\/--- /->,/ / i / /,/ 7-t -."-- 4 1-"/ />( / \/ ' , A r 'Is O J` -_, / .. // . f;>/iC..,,Z ..--... -, ) ' , />-•—.7 /. ./ /\ , i \ ' \ 7 \ N 7 4 / :Z >C/ /)i - OM; ---,, li t-/ /,,,/ ,/ ,, , A .7,,, / -, / „/ -, ,,„ ) \, ' ._,,f,,,,,: 74,•,,c -,-,,__ - - ,,/-s-f---- ---4 ----7,- . .dap--- ■ -1 ktiri , \ ‘1.1,. _>...,,z ,/- , \ V 7,-,.__ ---7-- 7„,-,-- -,,, ''.- _ / - - .4,0 . / -/- - . ///*# i c. k) —1 ___0 p, ---/*/c.__ .' Ilk- ", --7,..-/--- - ,.. ,:o. --0 / (0 I • E, o N / " o' e---- 1 k!k ' / ny(r / ../ o o N'�/ I CD CD• I III / \\ /• '/ w o Air $ \ /\ 1\ \I a '/ ...,ice. / 3 < j / c N (D/..... n o,l'�I I �/� �/�/ 4, k-1 3 3 3 3 -,* : 0,T, // /� / jj 1 : z v) o o- k / /\ c E � m 2 o i � CO a CD s A O O 0 W CG ,1 O. coC l / N 1 do i` Riverside Pre-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 9/30/2014 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 1 ow Summary for Subcatchment 1: Pre-Dev .I. Runoff = 9.45 cfs @ 12.27 hrs, Volume= 1.122 af, Depth> 0.69" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 2yr Rainfall=3.67" Area(sf) CN Description 460,672 55 Woods,Good, HSG B .. 261,790 70 Woods,Good,HSG C 106,760 61 >75%Grass cover,Good, HSG B * 23,084 98 Impervious 852,306 62 Weighted Average ®"` 829,222 97.29%Pervious Area 23,084 2.71%Impervious Area ,r Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 28.4 Direct Entry, ANI in YIN MIIII MI all it MIS MN MI Page 5 of 53 Riverside Pre-Development Type 1124-hr 10yr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 9/30/2014 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment 1: Pre-Dev Runoff = 29.20 cfs @ 12.24 hrs, Volume= 2.877 af, Depth> 1.76" 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=5.54" Area(sf) CN Description 460,672 55 Woods,Good, HSG B 261,790 70 Woods,Good, HSG C 106,760 61 >75%Grass cover,Good,HSG B * 23,084 98 Impervious 852,306 62 Weighted Average 829,222 97.29%Pervious Area 23,084 2.71%Impervious Area M. Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 28.4 Direct Entry, • Page 6 of 53 — Post-Development Stormwater Management Calculations Post-Development Drainage Map Post-Development HydroCAD Analysis .. .. a. Page 7 of 53 ms _ Eir,o..r Loos ir... ....M Ihri iri moil lasol 64 husell r - Ina 161111 buil I mil i mil irk Lori / _ - ;' \\" D O �/ "'► /%/I)// j' ' . V. \•. ri II I /�,' 2, -/ \�I\\ \ I / / . / yc \ I I loll , - i \ � \\ \ \ �_�. \\\ � I '/•I0\i,;I / / / %: i , / / ,/ r / — '\� {�� cn 03 —I O m \ �t /lli / / \ ° to o v \\ \ o IN �1' , // / ( \\\ \ '+ 5. co it'ifilillg i,,( , i-,/ / I ` 1 �,�\\\�`c 3- 0 0 N 4 it / �\ \VA ,n 7 . : 0. 0 ' 1!'all000e __/,____ ir_r_le _/ _ , ! 1.,colli-po . .i 1 it PP I[ii III �!/_ Ii1 \ / ''\____ -- , _IT_ coo (5, \... \I: frl 8 1\, t rill / _�'k\ ,\� \\ \_:::71111: • •.\. -011 -- p il, 1I!IIIIIF�,l //� // �/� /= '-'0K'� \�\N. �\ �/ //// �/, \ \ \\I\ ', \��\ \ Ii I� • I i' \ .../ ---- ------,--- 7"-------- ----....,, -,........ II -- ' - ,Ne•-=------=---- 4- ----="="=" _ N \\ ii.0 .4- 1,-,=.==== . \ \ \ \ \ \ \\ \ A 5 CD ICI' f� :=p '% �___= __%l�_ \\ \ \ �',�` 4�,____ \ \ \ \\\ \ ` I�� � ' ���'��'_ �' , . °�i� -vi-__ ��� ,.'. `� -_�� \\ \ \`,',�1,1 �I iii ✓�,���9_ = 4� j-i Q \\ .N.. _ . \----",\\\ \\ VIII ��, �� � A'� �� � - , .\,`�a ���—_ � � \ I\1 1 \`,,,I •�>•�'!� ell ti� _ ' , �� \ 111\ \ \.. II :w / ���;\ � , �\ ����\ I III I\'''•,\�\ \ // 1p 1 ) / / ■-...... ". , 4.--„ *. ■-=_L-.--_----_----?,..:•..: or,,,.. -4111kWa_=-----=, k\ ,i,). ■ \ -----..., , 11 ,....-/ I \ I( , „i„,,,, : N.4i, '1/4,,,.. --,,-- 0., 40,- __._:_..,- -...- - , , \ \ E _ —— • -- ;==',,,,`7,;„( / .� _ ./, ��1� f III �� ' _ _=_ _— /':5>�.'%� ��� CD 110 .41E" .# -:--''- ------ ----- --.-. -.-i,,,/;;404/ 7----+-k 1.‘ --7:-- '---,----■------ -;--:_ .'...'' K ..! _ -..___ _ . ..,,,,. , \\ .____,_j_ -....., ,„.,, 0 - 41; ----- --- I aP-.-.0- ---V-r.-:------ -. - .;4.1V;1. . ==== ------=–, - 1 C.4.>17.\, ---. 1 iii;,,v ,,,.:-... . _ _,_ 1 ... ,,,,;,,,,,o. .,-__:_--- -.--7.774,- - — ,...- --------j. , , ,././:,,,,,,, -x_._-_ ,...- ,-__-. it'ti-± 'ii–�\ = f4#'iJII'_ ■�i i 1 i/` I11 , --_\\ \ �I \I I > / III III'•. 11 N N 00 1 W N N O / co A O I 1111 I _ , O A D CO CO Z 4 y 0 co III 1j11� 1 o 1 ICI' ° `. — <° a F -. 1 \ \ I o m o m o F I ❑ 3 r�-� J 0 J 0 J (C F J (p 11 \�I r 1 a a a o a o 1 1 O i ' 1 c, O O w C cII iii 3 o- o ) - cw II ❑ a CD CD F) o w w O 0 O - N _ `R\ /J/ m 0 2. 1 O co. I O co m I� • ❑ 3 O S ❑ S n ❑ C C • Z _ 1 m m m m 7 1 O N CO 0 N W N O V f N w S ' !b N On (n A V W N A p, f 3 3 3 3 3 3 3 3 3 3 3 3 3 .-- 3 7 J 7 J 7 7 7 J 7 J J 0 • t 1 , ' T. N• N T. N D U-o <D -o o am S S co n n S S o 1 f II / i l a 1 1 I i ANY /11X DA D BMPD 4 3 11 1ZBMP C DA C / 6 \ Swale "Detention 12 7 Q as Bypass Bowl SCC DA to A4 14 Q-- 8 Point of Analysis Stream BMP B DA B Subcat Reach 'on• Drainage Diagram for Riverside Post-Development Prepared by Shimp Engineering,P.C., Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC gar Page 9 of 53 S Riverside Post-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 sin 07054 ©2011 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment 1:DA B Runoff = 4.13 cfs @ 12.04 hrs, Volume= 0.240 af, Depth> 2.00" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 2yr Rainfall=3.67" Area(sf) CN Description * 37,821 98 Impervious 25,143 61 >75%Grass cover,Good,HSG B 62,964 83 Weighted Average 25,143 39.93%Pervious Area 37,821 60.07%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) �,. 12.1 Direct Entry, Summary for Pond 2: BMP B Inflow Area= 1.445 ac, 60.07%Impervious, Inflow Depth> 2.00" for 2yr event Inflow = 4.13 cfs @ 12.04 hrs, Volume= 0.240 af Outflow = 0.16 cfs @ 14.30 hrs, Volume= 0.112 af, Atten=96%, Lag=135.9 min Primary = 0.16 cfs @ 14.30 hrs, Volume= 0.112 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=341.56'@ 14.30 hrs Surf.Area=8,900 sf Storage=6,697 cf Plug-Flow detention time=331.4 min calculated for 0.112 af(46%of inflow) Center-of-Mass det.time=212.8 min(1,040.0-827.2) Volume Invert Avail.Storage Storage Description #1 334.75' 586 cf AASHTO M43(Prismatic)Listed below(Recalc) 1,465 cf Overall x 40.0%Voids #2 335.75' 1,951 cf #3 Gravel(Prismatic)Listed below(Recalc) 3,903 cf Overall x 50.0%Voids #3 338.00' 222 cf #3 Gravel(Prismatic)Listed below(Recalc) �. 445 cf Overall x 50.0%Voids #4 338.00' 1,168 cf Biofilter Mix(Prismatic)Listed below(Recalc) 4,673 cf Overall x 25.0%Voids #5 340.50' 12,208 cf Custom Stage Data(Prismatic)Listed below(Recalc) 'S 16,136 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 334.75 1,385 0 0 335.75 1,544 1,465 1,465 S Page 10 of 53 S Riverside Post-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 3 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 335.75 1,544 0 0 338.00 1,925 3,903 3,903 Elevation Surf.Area Inc.Store Cum.Store IN (feet) (sq-ft) (cubic-feet) (cubic-feet) 338.00 288 0 0 339.50 305 445 445 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 338.00 1,648 0 0 r 340.50 2,090 4,673 4,673 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 340.50 2,090 0 0 341.00 2,558 1,162 1,162 341.10 2,740 265 1,427 +� 342.00 3,312 2,723 4,150 344.00 4,746 8,058 12,208 .r. Device Routing Invert Outlet Devices #1 Primary 333.60' 24.0" Round Pipe A3-A2 L=75.2' Ke=0.400 Inlet/Outlet Invert=333.60'/333.00' S=0.0080'/' Cc=0.900 n=0.013 #2 Device 1 341.00' 3.0"Vert.Orifice C=0.600 .. #3 Device 1 342.20' 24.0"Horiz.Nyloplast Standpipe C=0.600 Limited to weir flow at low heads #4 Primary 342.50' 15.0'long x 10.0'breadth Emergency Spillway Head(feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef.(English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=0.16 cfs @ 14.30 hrs HW=341.56' (Free Discharge) 1=Pipe Al-A2 (Passes 0.16 cfs of 42.25 cfs potential flow) 12=Orifice (Orifice Controls 0.16 cfs @ 3.19 fps) 3=Nyloplast Standpipe (Controls 0.00 cfs) =Emergency Spillway (Controls 0.00 cfs) Summary for Subcatchment 3: DA C Runoff = 2.29 cfs @ 12.02 hrs, Volume= 0.126 af, Depth> 1.92" 4.. Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 2yr Rainfall=3.67" Area(sf) CN Description * 19,718 98 Impervious 14,721 61 >75%Grass cover,Good,HSG B 34,439 82 Weighted Average 14,721 42.75%Pervious Area 19,718 57.25%Impervious Area Page 11 of 53 rr 'i` Riverside Post-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD'9.10 sin 07054 ©2011 HydroCAD Software Solutions LLC Page 4 mm Summary for Pond 4: BMP C ,r Inflow Area= 0.791 ac, 57.25%Impervious, Inflow Depth> 1.92" for 2yr event Inflow = 2.29 cfs @ 12.02 hrs, Volume= 0.126 af Outflow = 2.26 cfs @ 12.04 hrs, Volume= 0.113 af, Atten=2%, Lag=1.0 min Primary = 2.26 cfs @ 12.04 hrs, Volume= 0.113 af am Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=352.77'@ 12.04 hrs Surf.Area=1,327 sf Storage=780 cf Plug-Flow detention time=73.5 min calculated for 0.113 af(89%of inflow) Center-of-Mass det.time=20.6 min(849.7-829.2) +.. Volume Invert Avail.Storage Storage Description #1 349.25' 272 cf Soil Stratum(Prismatic)Listed below(Recalc) 1,088 cf Overall x 25.0%Voids #2 352.00' 1,776 cf Custom Stage Data(Prismatic)Listed below(Recalc) am 2,048 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store "' (feet) (sq-ft) (cubic-feet) (cubic-feet) 349.25 267 0 0 352.00 524 1,088 1,088 r. Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 352.00 524 0 0 "i 354.00 1,252 1,776 1,776 Device Routing Invert Outlet Devices m., #1 Primary 348.25' 15.0" Round Culvert L=17.7' Ke=0.400 Inlet/Outlet Invert=348.25'/347.00' S=0.0706'/' Cc=0.900 n=0.013 #2 Device 1 352.50' 48.0"Horiz.Orifice/Grate X 0.40 C=0.600 in 30.0"x 30.0"Grate Limited to weir flow at low heads ®' #3 Primary 353.00' 15.0'long x 10.0'breadth Broad-Crested Rectangular Weir Head(feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef.(English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 mm Primary OutFlow Max=2.25 cfs @ 12.04 hrs HW=352.77' (Free Discharge) 1=Culvert (Passes 2.25 cfs of 12.49 cfs potential flow) t2=Orifice/Grate (Weir Controls 2.25 cfs @ 0.67 fps) ®' 3=Broad-Crested Rectangular Weir (Controls 0.00 cfs) Summary for Subcatchment 5: DA to A4 Runoff = 2.49 cfs @ 12.17 hrs, Volume= 0.234 af, Depth> 0.69" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 2yr Rainfall=3.67" mm Page 12 of 53 mm Riverside Post-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD 9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 5 Area(sf) CN Description 172,761 61 >75%Grass cover,Good,HSG B * 4,001 98 Impervious 176,762 62 Weighted Average 172,761 97.74%Pervious Area 4,001 2.26%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 20.1 Direct Entry, Summary for Pond 6: Detention Inflow Area= 0.791 ac, 57.25%Impervious, Inflow Depth> 1.71" for 2yr event Inflow = 2.26 cfs @ 12.04 hrs, Volume= 0.113 af Outflow = 0.98 cfs @ 12.19 hrs, Volume= 0.113 af, Atten=56%, Lag=8.8 min Primary = 0.98 cfs @ 12.19 hrs, Volume= 0.113 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=343.46'@ 12.19 hrs Surf.Area=652 sf Storage=1,047 cf Plug-Flow detention time=7.1 min calculated for 0.113 af(100%of inflow) Center-of-Mass det.time=7.0 min(856.7-849.7) Volume Invert Avail.Storage Storage Description #1 341.00' 3,201 cf 72.0"D x 113.2'L Pipe Storage S=0.0050'/' Device Routing Invert Outlet Devices #1 Primary 341.00' 15.0" Round Culvert L=31.9' Ke=0.100 Inlet/Outlet Invert=341.00'/340.50' S=0.0157'/' Cc=0.900 n=0.013 �+. #2 Device 1 341.00' 5.0"Vert.Orifice/Grate C=0.600 #3 Device 1 343.50' 3.0"Vert.Orifice/Grate X 2.00 C=0.600 #4 Primary 345.40' Weir Plate Top X 2.00,Cv=2.62(C=3.28) Head(feet) 0.00 0.20 0.40 0.60 Width(feet) 3.60 2.99 2.15 0.00 Primary OutFlow Max=0.98 cfs @ 12.19 hrs HW=343.46' (Free Discharge) .o. 1=Culvert (Passes 0.98 cfs of 9.47 cfs potential flow) E2=Orifice/Grate (Orifice Controls 0.98 cfs @ 7.22 fps) 3=Orifice/Grate (Controls 0.00 cfs) =Weir Plate Top (Controls 0.00 cfs) r Summary for Reach 7:SCC +� Inflow Area= 6.294 ac, 22.45%Impervious, Inflow Depth> 0.82" for 2yr event Inflow = 3.48 cfs @ 12.17 hrs, Volume= 0.429 af Outflow = 3.44 cfs @ 12.21 hrs, Volume= 0.428 af, Atten=1%, Lag=2.7 min ®• Page 13 of 53 moo A. Riverside Post-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 6 +r Routing by Stor-Ind+Trans method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Max.Velocity=2.90 fps, Min.Travel Time=1.6 min Avg.Velocity=1.61 fps, Avg.Travel Time=2.9 min Peak Storage=332 cf @ 12.18 hrs Average Depth at Peak Storage=0.63' ,,. Bank-Full Depth=2.00', Capacity at Bank-Full=75.33 cfs 0.00' x 2.00' deep channel, n=0.050 Side Slope Z-value=2.0 4.0 7' Top Width=12.00' im Length=280.0' Slope=0.0482'/' Inlet Invert=332.00', Outlet Invert=318.50' ,r Summary for Reach 8:Stream Inflow Area= 6.294 ac, 22.45%Impervious, Inflow Depth> 0.82" for 2yr event Inflow = 3.44 cfs @ 12.21 hrs, Volume= 0.428 af .• Outflow = 3.33 cfs @ 12.31 hrs, Volume= 0.426 af, Atten=3%, Lag=5.9 min Routing by Stor-Ind+Trans method,Time Span=0.00-24.00 hrs,dt=0.01 hrs „r, Max.Velocity=2.46 fps, Min.Travel Time=3.2 min Avg.Velocity=1.31 fps, Avg.Travel Time=6.0 min Peak Storage=643 cf @ 12.26 hrs .0 Average Depth at Peak Storage=0.53' Bank-Full Depth=4.00', Capacity at Bank-Full=436.68 cfs 1.00' x 4.00' deep channel, n=0.030 mil Side Slope Z-value=3.0'/' Top Width=25.00' Length=474.9' Slope=0.0116'/' Inlet Invert=317.50', Outlet Invert=312.00' .. do Mil MN ..r Page 14 of 53 '.i. Riverside Post-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 7 s Summary for Subcatchment 9: DA D ar Runoff = 18.64 cfs @ 12.03 hrs, Volume= 1.035 af, Depth> 1.92" Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 2yr Rainfall=3.67" Area(sf) CN Description * 157,343 98 Impervious 124,607 61 >75%Grass cover,Good,HSG B 281,950 82 Weighted Average 124,607 44.19%Pervious Area 157,343 55.81%Impervious Area ar Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) All 10.8 Direct Entry, Summary for Pond 10: BMP D ao Inflow Area= 6.473 ac, 55.81%Impervious, Inflow Depth> 1.92" for 2yr event Inflow = 18.64 cfs @ 12.03 hrs, Volume= 1.035 af Outflow = 3.61 cfs @ 12.31 hrs, Volume= 0.702 af, Atten=81%, Lag=17.1 min ... Discarded = 0.17 cfs @ 10.51 hrs, Volume= 0.195 af Primary = 3.45 cfs @ 12.31 hrs, Volume= 0.507 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs am Peak Elev=337.45'@ 12.31 hrs Surf.Area=9,768 sf Storage=19,889 cf Plug-Flow detention time=185.6 min calculated for 0.702 af(68%of inflow) a. Center-of-Mass det.time=80.6 min(909.9-829.3) Volume Invert Avail.Storage Storage Description #1 334.00' 16,196 cf Custom Stage Data(Prismatic)Listed below(Recalc) .r 68,376 cf Overall-27,887 cf Embedded=40,489 cf x 40.0%Voids #2 335.00' 27,887 cf 72.0"D x 140.9'L Pipe Storage x 7 Inside#1 44,083 cf Total Available Storage a. Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) „r 334.00 9,768 0 0 341.00 9,768 68,376 68,376 Device Routing Invert Outlet Devices 'r #1 Discarded 334.00' 0.730 in/hr Exfiltration over Horizontal area #2 Primary 336.60' 18.0" Round Culvert L=73.6' Ke=0.100 Inlet/Outlet Invert=336.60'/335.56' S=0.0141'/' Cc=0.900 n=0.013 ,,, #3 Device 2 336.60' 9.0"Vert.Orifice/Grate X 2.00 C=0.600 #4 Device 2 336.60' 5.0"Vert.Orifice/Grate C=0.600 #5 Device 2 337.60' 3.0"Vert.Orifice/Grate C=0.600 a• Page 15 of 53 a M" Riverside Post-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD 9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 8 rr #6 Primary 339.70' Weir Plate X 3.00,Cv=2.62(C=3.28) Head(feet) 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.30 Width(feet) 4.94 4.64 4.28 3.85 3.32 2.62 1.54 0.00 IMA Discarded OutFlow Max=0.17 cfs @ 10.51 hrs HW=334.07' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.17 cfs) trimary OutFlow Max=3.45 cfs @ 12.31 hrs HW=337.45' (Free Discharge) -I=Culvert (Passes 3.45 cfs of 3.92 cfs potential flow) -3=Orifice/Grate (Orifice Controls 2.93 cfs @ 3.31 fps) -4=Orifice/Grate (Orifice Controls 0.53 cfs @ 3.85 fps) -5=Orifice/Grate (Controls 0.00 cfs) -6=Weir Plate (Controls 0.00 cfs) Summary for Reach 11:Swale Inflow Area= 6.473 ac, 55.81%Impervious, Inflow Depth> 0.94" for 2yr event Inflow = 3.45 cfs @ 12.31 hrs, Volume= 0.507 af Outflow = 3.45 cfs @ 12.35 hrs, Volume= 0.507 af, Atten=0%, Lag=2.3 min ,., Routing by Stor-Ind+Trans method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Max.Velocity=2.74 fps, Min.Travel Time=1.2 min Avg.Velocity=1.40 fps, Avg.Travel Time=2.4 min Peak Storage=257 cf @ 12.33 hrs Average Depth at Peak Storage=0.58' Bank-Full Depth=3.00', Capacity at Bank-Full=148.67 cfs 1.00' x 3.00' deep channel, n=0.050 Side Slope Z-value=2.0 7' Top Width=13.00' Length=203.7' Slope=0.0344'/' Inlet Invert=334.50', Outlet Invert=327.50' .r Summary for Reach 12: Bowl Inflow Area= 6.473 ac, 55.81%Impervious, Inflow Depth> 0.94" for 2yr event Inflow = 3.45 cfs @ 12.35 hrs, Volume= 0.507 af Outflow = 3.43 cfs @ 12.44 hrs, Volume= 0.506 af, Atten=1%, Lag=5.4 min Routing by Stor-Ind+Trans method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Max.Velocity=2.71 fps, Min.Travel Time=2.7 min Avg.Velocity=1.39 fps, Avg.Travel Time=5.2 min Page 16 of 53 .r. am tat Riverside Post-Development Type 1124-hr 2yr Rainfall=3.67" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 9 A. Peak Storage=546 cf @ 12.39 hrs Average Depth at Peak Storage=0.58' Bank-Full Depth=3.00', Capacity at Bank-Full=147.02 cfs r. 1.00' x 3.00' deep channel, n=0.050 Side Slope Z-value=2.0'/' Top Width=13.00' ,,,, Length=431.5' Slope=0.0336'/' Inlet Invert=326.50', Outlet Invert=312.00' mik Summary for Subcatchment 13: Bypass Runoff = 5.41 cfs @ 12.13 hrs, Volume= 0.445 af, Depth> 0.74" .,., Runoff by SCS TR-20 method,UH=SCS,Time Span=0.00-24.00 hrs,dt=0.01 hrs Type II 24-hr 2yr Rainfall=3.67" Area(sf) CN Description mis 140,889 70 Woods,Good,HSG C 142,518 55 Woods,Good,HSG B * 10,019 98 Impervious .r 21,595 61 >75%Grass cover,Good,HSG B 315,021 63 Weighted Average 305,002 96.82%Pervious Area 10,019 3.18%Impervious Area r Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 17.3 Direct Entry, Summary for Link 14: Point of Analysis Inflow Area= 19.999 ac, 26.28%Impervious, Inflow Depth> 0.83" for 2yr event Inflow = 9.13 cfs @ 12.31 hrs, Volume= 1.377 af Primary = 9.13 cfs @ 12.31 hrs, Volume= 1.377 af, Atten=0%, Lag=0.0 min w Primary outflow=Inflow,Time Span=0.00-24.00 hrs,dt=0.01 hrs am mo Page 17 of 53 `"`m Riverside Post-Development Type 1124-hr 10yr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 1/20/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 10 Summary for Subcatchment 1:DA B wog Runoff = 7.46 cfs @ 12.04 hrs, Volume= 0.440 af, Depth> 3.66" 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=5.54" Area(sf) CN Description * 37,821 98 Impervious .�. 25,143 61 >75%Grass cover,Good,HSG B 62,964 83 Weighted Average 25,143 39.93%Pervious Area 37,821 60.07%Impervious Area aim Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) �,. 12.1 Direct Entry, Summary for Pond 2: BMP B Inflow Area= 1.445 ac, 60.07%Impervious, Inflow Depth> 3.66" for 10yr event Inflow = 7.46 cfs @ 12.04 hrs, Volume= 0.440 af Outflow = 2.52 cfs @ 12.23 hrs, Volume= 0.295 af, Atten=66%, Lag=11.4 min Primary = 2.52 cfs @ 12.23 hrs, Volume= 0.295 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=342.43'@ 12.23 hrs Surf.Area=9,484 sf Storage=9,565 cf Plug-Flow detention time=249.8 min calculated for 0.295 af(67%of inflow) Center-of-Mass det.time=149.4 min(959.5-810.1) ,rr Volume Invert Avail.Storage Storage Description #1 334.75' 586 cf AASHTO M43(Prismatic)Listed below(Recalc) 1,465 cf Overall x 40.0%Voids #2 335.75' 1,951 cf #3 Gravel(Prismatic)Listed below(Recalc) 3,903 cf Overall x 50.0%Voids #3 338.00' 222 cf #3 Gravel(Prismatic)Listed below(Recalc) 445 cf Overall x 50.0%Voids #4 338.00' 1,168 cf Biofilter Mix(Prismatic)Listed below(Recalc) 4,673 cf Overall x 25.0%Voids #5 340.50' 12,208 cf Custom Stage Data(Prismatic)Listed below(Recalc) 16,136 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store .. (feet) (sq-ft) (cubic-feet) (cubic-feet) 334.75 1,385 0 0 335.75 1,544 1,465 1,465 Page 18 of 53 Riverside Post-Development Type 1124-hr 10yr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 11 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 335.75 1,544 0 0 338.00 1,925 3,903 3,903 Elevation Surf.Area Inc.Store Cum.Store y.. (feet) (sq-ft) (cubic-feet) (cubic-feet) 338.00 288 0 0 339.50 305 445 445 a Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 338.00 1,648 0 0 340.50 2,090 4,673 4,673 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 340.50 2,090 0 0 341.00 2,558 1,162 1,162 341.10 2,740 265 1,427 a 342.00 3,312 2,723 4,150 344.00 4,746 8,058 12,208 Device Routing Invert Outlet Devices #1 Primary 333.60' 24.0" Round Pipe A1-A2 L=75.2' Ke=0.400 Inlet/Outlet Invert=333.60'/333.00' S=0.0080'/' Cc=0.900 n=0.013 #2 Device 1 341.00' 3.0"Vert.Orifice C=0.600 #3 Device 1 342.20' 24.0"Horiz.Nyloplast Standpipe C=0.600 Limited to weir flow at low heads #4 Primary 342.50' 15.0'long x 10.0'breadth Emergency Spillway Head(feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef.(English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 primary OutFlow Max=2.52 cfs @ 12.23 hrs HW=342.43' (Free Discharge) -1=Pipe A1-A2 (Passes 2.52 cfs of 44.95 cfs potential flow) 12=Orifice (Orifice Controls 0.27 cfs @ 5.50 fps) 3=Nyloplast Standpipe (Weir Controls 2.25 cfs @ 1.56 fps) -4=Emergency Spillway (Controls 0.00 cfs) Summary for Subcatchment 3: DA C Runoff = 4.19 cfs @ 12.02 hrs, Volume= 0.234 af, Depth> 3.56" 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=5.54" Area(sf) CN Description * 19,718 98 Impervious 14,721 61 >75%Grass cover,Good,HSG B 34,439 82 Weighted Average 14,721 42.75%Pervious Area 19,718 57.25%Impervious Area Page 19 of 53 a Mit Riverside Post-Development Type 1124-hr 10yr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 12 ar Summary for Pond 4: BMP C Inflow Area= 0.791 ac, 57.25%Impervious, Inflow Depth> 3.56" for 10yr event Inflow = 4.19 cfs @ 12.02 hrs, Volume= 0.234 af Outflow = 4.14 cfs @ 12.04 hrs, Volume= 0.221 af, Atten=1%, Lag=0.9 min Primary = 4.14 cfs @ 12.04 hrs, Volume= 0.221 af .sr Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=352.90'@ 12.04 hrs Surf.Area=1,375 sf Storage=890 cf Plug-Flow detention time=47.7 min calculated for 0.221 af(94%of inflow) Center-of-Mass det.time=15.6 min(827.3-811.7) a Volume Invert Avail.Storage Storage Description #1 349.25' 272 cf Soil Stratum(Prismatic)Listed below(Recalc) 1,088 cf Overall x 25.0%Voids #2 352.00' 1,776 cf Custom Stage Data(Prismatic)Listed below(Recalc) 2,048 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 349.25 267 0 0 352.00 524 1,088 1,088 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 352.00 524 0 0 354.00 1,252 1,776 1,776 Device Routing Invert Outlet Devices #1 Primary 348.25' 15.0" Round Culvert L=17.7' Ke=0.400 Inlet/Outlet Invert=348.25'/347.00' S=0.07067' Cc=0.900 n=0.013 #2 Device 1 352.50' 48.0"Horiz.Orifice/Grate X 0.40 C=0.600 in 30.0"x 30.0"Grate Limited to weir flow at low heads a #3 Primary 353.00' 15.0'long x 10.0'breadth Broad-Crested Rectangular Weir Head(feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef.(English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=4.13 cfs @ 12.04 hrs HW=352.90' (Free Discharge) 1=Culvert (Passes 4.13 cfs of 12.70 cfs potential flow) t2=Orifice/Grate (Weir Controls 4.13 cfs @ 0.83 fps) yr 3=Broad-Crested Rectangular Weir (Controls 0.00 cfs) Summary for Subcatchment 5: DA to A4 INN Runoff = 7.58 cfs @ 12.14 hrs, Volume= 0.599 af, Depth> 1.77" 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=5.54" Page 20 of 53 a xis Riverside Post-Development Type I124-hr 10yr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 13 r Area(sf) CN Description 172,761 61 >75%Grass cover,Good,HSG B * 4,001 98 Impervious a. 176,762 62 Weighted Average 172,761 97.74%Pervious Area 4,001 2.26%Impervious Area s Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) WO 20.1 Direct Entry, Summary for Pond 6: Detention Inflow Area= 0.791 ac, 57.25%Impervious, Inflow Depth> 3.35" for 10yr event Inflow = 4.14 cfs @ 12.04 hrs, Volume= 0.221 af Outflow = 1.93 cfs @ 12.17 hrs, Volume= 0.221 af, Atten=53%, Lag=8.1 min MS Primary = 1.93 cfs @ 12.17 hrs, Volume= 0.221 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=345.28'@ 12.17 hrs Surf.Area=639 sf Storage=2,267 cf *ft Plug-Flow detention time=9.7 min calculated for 0.221 af(100%of inflow) Center-of-Mass det.time=9.6 min(836.9-827.3) Volume Invert Avail.Storage Storage Description #1 341.00' 3,201 cf 72.0"D x 113.2'L Pipe Storage S=0.0050'/' as Device Routing Invert Outlet Devices #1 Primary 341.00' 15.0" Round Culvert L=31.9' Ke=0.100 Inlet/Outlet Invert=341.00'/340.50' S=0.0157 7' Cc=0.900 n=0.013 . #2 Device 1 341.00' 5.0"Vert.Orifice/Grate C=0.600 #3 Device 1 343.50' 3.0"Vert.Orifice/Grate X 2.00 C=0.600 #4 Primary 345.40' Weir Plate Top X 2.00,Cv=2.62(C=3.28) Head(feet) 0.00 0.20 0.40 0.60 Ais Width(feet) 3.60 2.99 2.15 0.00 Primary Outflow Max=1.93 cfs @ 12.17 hrs HW=345.28' (Free Discharge) ,r 1=Culvert (Passes 1.93 cfs of 13.63 cfs potential flow) E2=Orifice/Grate (Orifice Controls 1.33 cfs @ 9.72 fps) 3=Orifice/Grate (Orifice Controls 0.61 cfs @ 6.20 fps) =Weir Plate Top (Controls 0.00 cfs) im Summary for Reach 7:SCC M' Inflow Area= 6.294 ac, 22.45%Impervious, Inflow Depth> 2.08" for 10yr event Inflow = 11.92 cfs @ 12.18 hrs, Volume= 1.090 af Outflow = 11.82 cfs @ 12.22 hrs, Volume= 1.088 af, Atten=1%, Lag=2.1 min .r Page 21 of 53 Riverside Post-Development Type 1124-hr 10yr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 14 wr Routing by Stor-Ind+Trans method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Max.Velocity=3.95 fps, Min.Travel Time=1.2 min Avg.Velocity=1.93 fps, Avg.Travel Time=2.4 min Peak Storage=838 cf @ 12.20 hrs Average Depth at Peak Storage=1.00' ... Bank-Full Depth=2.00', Capacity at Bank-Full=75.33 cfs 0.00' x 2.00' deep channel, n=0.050 Side Slope Z-value=2.0 4.0'/' Top Width=12.00' Length=280.0' Slope=0.0482'/' Inlet Invert=332.00', Outlet Invert=318.50' Summary for Reach 8:Stream Inflow Area= 6.294 ac, 22.45%Impervious, Inflow Depth> 2.07" for 10yr event Inflow = 11.82 cfs @ 12.22 hrs, Volume= 1.088 af Outflow = 11.50 cfs @ 12.29 hrs, Volume= 1.084 af, Atten=3%, Lag=4.2 min Routing by Stor-Ind+Trans method,Time Span=0.00-24.00 hrs,dt=0.01 hrs ,,■ Max.Velocity=3.37 fps, Min.Travel Time=2.3 min Avg.Velocity=1.60 fps, Avg.Travel Time=5.0 min Peak Storage=1,618 cf @ 12.25 hrs Average Depth at Peak Storage=0.91' Bank-Full Depth=4.00', Capacity at Bank-Full=436.68 cfs 1.00' x 4.00' deep channel, n=0.030 Side Slope Z-value=3.0 7' Top Width=25.00' Length=474.9' Slope=0.0116'1 Inlet Invert=317.50', Outlet Invert=312.00' i rr Page 22 of 53 aft �. Riverside Post-Development Type 1124-hr 10yr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 15 wr Summary for Subcatchment 9: DA D Runoff = 34.03 cfs @ 12.02 hrs, Volume= 1.919 af, Depth> 3.56" 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=5.54" Area(sf) CN Description * 157,343 98 Impervious 124,607 61 >75%Grass cover,Good,HSG B 281,950 82 Weighted Average 124,607 44.19%Pervious Area 157,343 55.81%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) w 10.8 Direct Entry, Summary for Pond 10: BMP D Inflow Area= 6.473 ac, 55.81%Impervious, Inflow Depth> 3.56" for l0yr event Inflow = 34.03 cfs @ 12.02 hrs, Volume= 1.919 af Outflow = 8.53 cfs @ 12.24 hrs, Volume= 1.574 af, Atten=75%, Lag=13.2 min Discarded = 0.17 cfs @ 8.72 hrs, Volume= 0.222 af Primary = 8.37 cfs @ 12.24 hrs, Volume= 1.352 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=339.63'@ 12.24 hrs Surf.Area=9,768 sf Storage=35,883 cf Plug-Flow detention time=130.1 min calculated for 1.574 af(82%of inflow) �+ Center-of-Mass det.time=54.2 min(866.1-811.9) Volume Invert Avail.Storage Storage Description #1 334.00' 16,196 cf Custom Stage Data(Prismatic)Listed below(Recalc) 68,376 cf Overall-27,887 cf Embedded=40,489 cf x 40.0%Voids #2 335.00' 27,887 cf 72.0"D x 140.9'L Pipe Storage x 7 Inside#1 44,083 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) ,,. 334.00 9,768 0 0 341.00 9,768 68,376 68,376 Device Routing Invert Outlet Devices #1 Discarded 334.00' 0.730 in/hr Exfiltration over Horizontal area #2 Primary 336.60' 18.0" Round Culvert L=73.6' Ke=0.100 Inlet/Outlet Invert=336.60'/335.56' S=0.0141'/' Cc=0.900 n=0.013 #3 Device 2 336.60' 9.0"Vert.Orifice/Grate X 2.00 C=0.600 #4 Device 2 336.60' 5.0"Vert.Orifice/Grate C=0.600 #5 Device 2 337.60' 3.0"Vert.Orifice/Grate C=0.600 Page 23 of 53 a. Riverside Post-Development Type 1124-hr 10yr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 sin 07054 ©2011 HydroCAD Software Solutions LLC Page 16 #6 Primary 339.70' Weir Plate X 3.00,Cv=2.62(C=3.28) Head(feet) 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.30 Width(feet) 4.94 4.64 4.28 3.85 3.32 2.62 1.54 0.00 Discarded OutFlow Max=0.17 cfs @ 8.72 hrs HW=334.07' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.17 cfs) Primary OutFlow Max=8.37 cfs @ 12.24 hrs HW=339.63' (Free Discharge) -I=Culvert (Passes 8.37 cfs of 14.55 cfs potential flow) -3=Orifice/Grate (Orifice Controls 6.94 cfs @ 7.85 fps) ""' -4=Orifice/Grate (Orifice Controls 1.10 cfs @ 8.09 fps) -5=Orifice/Grate (Orifice Controls 0.33 cfs @ 6.65 fps) -6=Weir Plate (Controls 0.00 cfs) so Summary for Reach 11:Swale a.. Inflow Area= 6.473 ac, 55.81%Impervious, Inflow Depth> 2.51" for l0yr event Inflow = 8.37 cfs @ 12.24 hrs, Volume= 1.352 af Outflow = 8.36 cfs @ 12.27 hrs, Volume= 1.351 af, Atten=0%, Lag=1.8 min No Routing by Stor-Ind+Trans method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Max.Velocity=3.44 fps, Min.Travel Time=1.0 min Avg.Velocity=1.80 fps, Avg.Travel Time=1.9 min m` Peak Storage=496 cf @ 12.26 hrs Average Depth at Peak Storage=0.88' Bank-Full Depth=3.00', Capacity at Bank-Full=148.67 cfs or 1.00' x 3.00' deep channel, n=0.050 Side Slope Z-value=2.0'/' Top Width=13.00' Length=203.7' Slope=0.0344 7' - Inlet Invert=334.50', Outlet Invert=327.50' a. Summary for Reach 12: Bowl Inflow Area= 6.473 ac, 55.81%Impervious, Inflow Depth> 2.50" for 10yr event Inflow = 8.36 cfs @ 12.27 hrs, Volume= 1.351 af Outflow = 8.35 cfs @ 12.34 hrs, Volume= 1.348 af, Atten=0%, Lag=4.0 min MI Routing by Stor-Ind+Trans method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Max.Velocity=3.41 fps, Min.Travel Time=2.1 min ,r Avg.Velocity=1.79 fps, Avg.Travel Time=4.0 min AN Page 24 of 53 am Riverside Post-Development Type 1124-hr 1Oyr Rainfall=5.54" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 17 Peak Storage=1,057 cf @ 12.30 hrs Average Depth at Peak Storage=0.88' Bank-Full Depth=3.00', Capacity at Bank-Full=147.02 cfs 1.00' x 3.00' deep channel, n=0.050 Side Slope Z-value=2.0'/' Top Width=13.00' Length=431.5' Slope=0.0336'1 Inlet Invert=326.50', Outlet Invert=312.00' Summary for Subcatchment 13: Bypass Runoff = 15.58 cfs @ 12.11 hrs, Volume= 1.115 af, Depth> 1.85" 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=5.54" Area(sf) CN Description 140,889 70 Woods,Good,HSG C 142,518 55 Woods,Good,HSG B * 10,019 98 Impervious 21,595 61 >75%Grass cover,Good,HSG B 315,021 63 Weighted Average 305,002 96.82%Pervious Area 10,019 3.18%Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 17.3 Direct Entry, Summary for Link 14: Point of Analysis Inflow Area= 19.999 ac, 26.28%Impervious, Inflow Depth> 2.13" for 10yr event Inflow = 29.18 cfs @ 12.21 hrs, Volume= 3.548 af Primary = 29.18 cfs @ 12.21 hrs, Volume= 3.548 af, Atten=0%, Lag=0.0 min a• Primary outflow=Inflow,Time Span=0.00-24.00 hrs,dt=0.01 hrs rr Page 25 of 53 Mal mia` Riverside Post-Development Type 1124-hr 100yr Rainfall=9.10" Prepared by Shimp Engineering, P.C. Printed 1/20/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 18 ..r Summary for Pond 2: BMP B A„ Inflow Area= 1.445 ac, 60.07%Impervious, Inflow Depth> 7.02" for 100yr event Inflow = 13.87 cfs @ 12.03 hrs, Volume= 0.845 af Outflow = 13.59 cfs @ 12.05 hrs, Volume= 0.671 af, Atten=2%, Lag=1.3 min Primary = 13.59 cfs @ 12.05 hrs, Volume= 0.671 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=342.75'@ 12.05 hrs Surf.Area=9,715 sf Storage=10,772 cf AM Plug-Flow detention time=150.2 min calculated for 0.671 af(79%of inflow) Center-of-Mass det.time=70.2 min(862.1-791.9) Am Volume Invert Avail.Storage Storage Description #1 334.75' 586 cf AASHTO M43(Prismatic)Listed below(Recalc) 1,465 cf Overall x 40.0%Voids #2 335.75' 1,951 cf #3 Gravel(Prismatic)Listed below(Recalc) 3,903 cf Overall x 50.0%Voids #3 338.00' 222 cf #3 Gravel(Prismatic)Listed below(Recalc) 445 cf Overall x 50.0%Voids +r #4 338.00' 1,168 cf Biofilter Mix(Prismatic)Listed below(Recalc) 4,673 cf Overall x 25.0%Voids #5 340.50' 12,208 cf Custom Stage Data(Prismatic)Listed below(Recalc) .I 16,136 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 334.75 1,385 0 0 335.75 1,544 1,465 1,465 .. Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 335.75 1,544 0 0 338.00 1,925 3,903 3,903 mig Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) ,,,. 338.00 288 0 0 339.50 305 445 445 Elevation Surf.Area Inc.Store Cum.Store "" (feet) (sq-ft) (cubic-feet) (cubic-feet) 338.00 1,648 0 0 340.50 2,090 4,673 4,673 .. Mall Ail Page 26 of 53 ma MIS Riverside Post-Development Type 1124-hr IOOyr Rainfall=9.10" Prepared by Shimp Engineering, P.C. Printed 1/20/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 19 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 340.50 2,090 0 0 341.00 2,558 1,162 1,162 341.10 2,740 265 1,427 342.00 3,312 2,723 4,150 A. 344.00 4,746 8,058 12,208 Device Routing Invert Outlet Devices #1 Primary 333.60' 24.0" Round Pipe A1-A2 L=75.2' Ke=0.400 Inlet/Outlet Invert=333.60'/333.00' S=0.0080'/' Cc=0.900 n=0.013 #2 Device 1 341.00' 3.0"Vert.Orifice C=0.600 #3 Device 1 342.20' 24.0"Horiz.Nyloplast Standpipe C=0.600 Limited to weir flow at low heads �.. #4 Primary 342.50' 15.0'long x 10.0'breadth Emergency Spillway Head(feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 Coef.(English) 2.49 2.56 2.70 2.69 2.68 2.69 2.67 2.64 Primary OutFlow Max=13.48 cfs @ 12.05 hrs HW=342.75' (Free Discharge) 1=Pipe A1-A2 (Passes 8.73 cfs of 45.91 cfs potential flow) 12=Orifice (Orifice Controls 0.30 cfs @ 6.14 fps) �. 3=Nyloplast Standpipe (Weir Controls 8.42 cfs @ 2.43 fps) =Emergency Spillway (Weir Controls 4.76 cfs @ 1.26 fps) Summary for Pond 4: BMP C Inflow Area= 0.791 ac, 57.25%Impervious, Inflow Depth> 6.89" for 100yr event Inflow = 7.86 cfs @ 12.02 hrs, Volume= 0.454 af ... Outflow = 7.83 cfs @ 12.03 hrs, Volume= 0.440 af, Atten=0%, Lag=0.4 min Primary = 7.83 cfs @ 12.03 hrs, Volume= 0.440 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=353.07'@ 12.03 hrs Surf.Area=1,438 sf Storage=1,042 cf Plug-Flow detention time=30.3 min calculated for 0.440 af(97%of inflow) ... Center-of-Mass det.time=12.2 min(805.4-793.2) Volume Invert Avail.Storage Storage Description #1 349.25' 272 cf Soil Stratum(Prismatic)Listed below(Recalc) 1,088 cf Overall x 25.0%Voids #2 352.00' 1,776 cf Custom Stage Data(Prismatic)Listed below(Recalc) 2,048 cf Total Available Storage Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) �. 349.25 267 0 0 352.00 524 1,088 1,088 Elevation Surf.Area Inc.Store Cum.Store ..� (feet) (sq-ft) (cubic-feet) (cubic-feet) 352.00 524 0 0 354.00 1,252 1,776 1,776 Page 27 of 53 ..r Riverside Post-Development Type 1124-hr IOOyr Rainfall=9.10" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 sin 07054 ©2011 HydroCAD Software Solutions LLC Page 20 Summary for Pond 6: Detention Inflow Area= 0.791 ac, 57.25%Impervious, Inflow Depth> 6.69" for 100yr event Inflow = 7.83 cfs @ 12.03 hrs, Volume= 0.440 af Outflow = 7.79 cfs @ 12.04 hrs, Volume= 0.440 af, Atten=1%, Lag=0.6 min Primary = 7.79 cfs @ 12.04 hrs, Volume= 0.440 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=345.83'@ 12.04 hrs Surf.Area=580 sf Storage=2,603 cf Plug-Flow detention time=7.9 min calculated for 0.440 af(100%of inflow) Center-of-Mass det.time=7.8 min(813.2-805.4) Volume Invert Avail.Storage Storage Description #1 341.00' 3,201 cf 72.0"D x 113.2'L Pipe Storage S=0.0050'/' Device Routing Invert Outlet Devices #1 Primary 341.00' 15.0" Round Culvert L=31.9' Ke=0.100 Inlet/Outlet Invert=341.00'/340.50' S=0.0157'/' Cc=0.900 n=0.013 #2 Device 1 341.00' 5.0"Vert.Orifice/Grate C=0.600 #3 Device 1 343.50' 3.0"Vert.Orifice/Grate X 2.00 C=0.600 #4 Primary 345.40' Weir Plate Top X 2.00,Cv=2.62(C=3.28) Head(feet) 0.00 0.20 0.40 0.60 Width(feet) 3.60 2.99 2.15 0.00 Primary OutFlow Max=7.79 cfs @ 12.04 hrs HW=345.83' (Free Discharge) 1=Culvert (Passes 2.11 cfs of 14.66 cfs potential flow) .. '2=Orifice/Grate (Orifice Controls 1.41 cfs @ 10.36 fps) 3=Orifice/Grate (Orifice Controls 0.70 cfs @ 7.16 fps) =Weir Plate Top (Weir Controls 5.67 cfs @ 2.29 fps) Summary for Pond 10: BMP D Inflow Area= 6.473 ac, 55.81%Impervious, Inflow Depth> 6.89" for 100yr event Inflow = 63.88 cfs @ 12.02 hrs, Volume= 3.719 af Outflow = 60.76 cfs @ 12.05 hrs, Volume= 3.358 af, Atten=5%, Lag=1.9 min Discarded = 0.17 cfs @ 6.09 hrs, Volume= 0.255 af Primary = 60.60 cfs @ 12.05 hrs, Volume= 3.103 af Routing by Stor-Ind method,Time Span=0.00-24.00 hrs,dt=0.01 hrs Peak Elev=340.88'@ 12.05 hrs Surf.Area=9,768 sf Storage=43,526 cf Plug-Flow detention time=88.7 min calculated for 3.357 af(90%of inflow) Center-of-Mass det.time=39.5 min(832.8-793.3) Volume Invert Avail.Storage Storage Description #1 334.00' 16,196 cf Custom Stage Data(Prismatic)Listed below(Recalc) 68,376 cf Overall-27,887 cf Embedded=40,489 cf x 40.0%Voids #2 335.00' 27,887 cf 72.0"D x 140.9'L Pipe Storage x 7 Inside#1 44,083 cf Total Available Storage Page 28 of 53 Riverside Post-Development Type 1124-hr 1O0yr Rainfall=9.10" Prepared by Shimp Engineering, P.C. Printed 1/19/2015 HydroCAD®9.10 s/n 07054 ©2011 HydroCAD Software Solutions LLC Page 21 Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) arr 334.00 9,768 0 0 341.00 9,768 68,376 68,376 Device Routing Invert Outlet Devices #1 Discarded 334.00' 0.730 in/hr Exfiltration over Horizontal area #2 Primary 336.60' 18.0" Round Culvert L=73.6' Ke=0.100 Inlet/Outlet Invert=336.60'/335.56' S=0.0141'/' Cc=0.900 n=0.013 #3 Device 2 336.60' 9.0"Vert.Orifice/Grate X 2.00 C=0.600 #4 Device 2 336.60' 5.0"Vert.Orifice/Grate C=0.600 #5 Device 2 337.60' 3.0"Vert.Orifice/Grate C=0.600 #6 Primary 339.70' Weir Plate X 3.00,Cv=2.62(C=3.28) �. Head(feet) 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.30 Width(feet) 4.94 4.64 4.28 3.85 3.32 2.62 1.54 0.00 Discarded OutFlow Max=0.17 cfs @ 6.09 hrs HW=334.07' (Free Discharge) t1=Exfiltration (Exfiltration Controls 0.17 cfs) erimary OutFlow Max=60.55 cfs® 12.05 hrs HW=340.88' (Free Discharge) 3=Culvert (Passes 10.15 cfs of 17.72 cfs potential flow) -3=Orifice/Grate (Orifice Controls 8.40 cfs @ 9.51 fps) -4=Orifice/Grate (Orifice Controls 1.32 cfs @ 9.71 fps) -5=Orifice/Grate (Orifice Controls 0.42 cfs @ 8.55 fps) -6=Weir Plate (Weir Controls 50.40 cfs @ 3.86 fps) .w .r. ..r ®w Page 29 of 53 rrrr .. Stormwater Quality Calculations Water Quality Map VSWMH Worksheet 5D1 VSWMH Worksheet 5D2 Boring Location Map BMP D Stage-Storage Table from HydroCAD .. .. .. Page 30 of 53 w+ immvii Irma liummi haul 6.4 il . — \ . Xs..) "- \ ■ •\ ct) 0 r,) \ > 0 \ , . 0 \* \.-„ \ \ -- ..\ \ m \‘ \ II \ k• \N\ --1. I --, Iv 0 cs) \\4\ik\ : \ ‘ . _1 ." , \‘'‘‘ \ \ 1 ..S... ..__. j- .. ,,, 2 2 0 \24%,\ \ \ • ..,._. co —‘ c • \ til N. 4k‘ \ • 1 I --' • ■I • CA) ... 1 si V, ' \ 11 : ■.... -El 4 \ K > . \N\ ' 0 ci 0 xi , . \Nt.\\ \ • IIIV . - ' 73 0 > ..--...,„ . , > 0 0 1— . I nr.1 ' ‘ , •\ •• N., co -a "a co \ •. 4,. cr) K c 0 X .0) li- II c), ,= -° m co Z —I X M Cfl M —a. 71 ei > 0 M ") \\ \ -. . • \.. \.. \. , • —. 0 —I MI < \ \ m — 0 -n m F m 0 < \ \ A0) z _1 0 _ . 0 m N • . . J , , , , N 1 . 7 -. , , - , 7 .., , . N. .‘ 4111 , -- , - 7 -,, \ \ . .- <53 . a .„.. * ,...,.. vs _,-/j 14.:-... , ifIIIIIIu .,'"■._ . ' ' -. s2. \O *‘. --4 1 I !:1""V* ,',.. s.s■ ....111. ull.. ''' P • AA/ •'', X'k(kt\ • ‘------k,, , .,0 •.4, 1: ) 1 `---"-'4. - — ----- 4 t, /7-7—,___,_ • ' a'--- -..■ A.,.. -------11.1i, \ A __ - -'ir. ,...0 --.."°°°'' Ill N., II PS. ...____ . \•,., lz,\ A ....j rr7 ..,,-..,..- \ ... --... ....-,• (1) i .,. Ii J ii 41440 1.fi---, --=fO -1 — L,.....,.-1..I=.„0/ ,__-_ --._, ---.-73---.—L -_--- - cy, co p 0 ee,- --=_,_4-- --77--7' ".1\. ,s;, ,-,--='----•—=--__ _.--- ---- ---a'- \At._ ., 41?-__ "--. ---- -- --,,, '',e7f .-.■.._. _\ st. --:-_— _,-_=-_=-__-_.----7.3- , _,, --- ve-- 9, K - .=..•_-_-_-.-. ,--,-__=- ..40.1;:.•.1,0:„_.-_-.._,_.., \ ,• -_ _.__...- -,•,-- iii-- '6--.. -0 1 ..) ) .__-...._.t.- --= -''- '-'•:,- '-:-=-- ---=-----,-_-.:—__ -7---T.* \ 0 13 03 CO : 1 T1 C? m co 0 [: .1 :: . _ ---z--___.- _- -_- C: (3 I ii -;••-•,. .,,. ,:,_._-_:_.=. --- --_ ---,-. 40 .--_, 0 p . m -n L ,„:. -_-=._. =-_ -__,_._. - -•;.* 0 , . .1■ pr,.i --a-_ ----i-----• 0 . .. • . z -< %1 1 44,,------- -------.... 0 , . --_,-_____ -- r-' ..._ ,.. I.-: —.-- -•--- '---t. 74 , 1111 MP° I I -1- ' 'cbcA) 41.° 'cop F..) 1 ti 1 -i . p -ti _. CP V ..... 13 CO C.A.) > I * „Or K m INI Pr Mes N 1 1 ,,....,_ . • I I -9 1 I 12 I fo F i Oa co.13 o n" a ni > g t 3 3 M < 0 a V < IT 7 a, CD Co.) 0 Cll Cx.) Riverside Village Outparcel Worksheet 1 page 1 of 3 STEP 1 Determine the applicable area (A) and the post-developed impervious cover(Lost). Applicable Area(A)* = 8.61 acres Post-development impervious cover: structures= 0.00 acres AI„ parking lot+ acres roadway= 0.45 acres other: �,. sidewalk= 0.00 acres acres Total = 0.45 acres ,m„ Ipost=(total post-development impervious cover-A)x 100= 5.2% * The area subject to the criteria may vary from locality to locality. Therefore, consult the locality for proper determination of this value. ,.. STEP 2 Determine the average land cover condition (Iwatershed) or the existing impervious cover(Iexisting). ,IN Average land cover condition (I,,,atershed): If the locality has determined land cover conditions for individual watersheds within its jurisdiction, use the watershed specific value determined by the locality as watershed. 'watershed= �o Otherwise, use the Chesapeake Bay default value: 'watershed= 16% rr ar Page 32 of 53 PERFORMANCE-BASED WATER QUALITY CALCULATIONS Worksheet 1 page 2 of 3 Existing impervious cover Determine the existing impervious cover of the development site if present. Existing impervious cover: structures= 0 acres parking lot= 0 acres roadway= 0.17 acres other: acres acres Total= 0.17 acres 'existing=(total existing impervious cover±A*)x 100= 2% * The area should be the same as used in STEP 1 STEP 3 Determine the appropriate development situation. The site information determined in STEP 1 and STEP 2 provide enough information to determine the appropriate development situation under which the performance criteria will apply. Check(V)the appropriate development situation as follows: - -Situation 1: This consists of land development where the existing percent impervious cover(-existing) is less than or equal to the average land cover condition ('watershed) and the proposed improvements will create a total percent impervious cover(Ipost) which is less than or equal to the average land cover condition(Iatershed). "post 5'watershed Page 33 of 53 PERFORMANCE-BASED WATER QUALITY CALCULATIONS Worksheet 1 page 3 of 3 Situation 2: This consists of land development where the existing percent impervious cover(existing) is less than or equal to the average land cover condition (Iwatershed)and the proposed improvements will create a total percent impervious cover(Ipost)which is greater than the average land cover condition ('watershed)• rr 'existing 2.0% <'watershed 16.0% ; and 'post 5.2% > 'watershed 16.0% Situation 3: This consists of land development where the existing percent impervious cover(Iexisting) is greater than the average land cover condition ('watershed)• 0 'existing > 'watershed o, and arr Situation 4: This consists of land development where the existing percent impervious cover ('existing)is served by an existing stormwater management BMP(s)that addresses water quality. If the proposed development meets the criteria for development Situation 1,than the low density development is considered to be the BMP and no pollutant removal is required. The calculation procedure for Situation 1 stops here. If the proposed development meets the criteria for development Situations 2,3,or 4,then proceed to STEP 4 on the appropriate worksheet. AIM gal Page 34 of 53 a Riverside Village Phase 1 Worksheet 1 page l of 3 STEP 1 Determine the applicable area(A) and the post-developed impervious cover(post). Applicable Area(A)* = 10.96 acres Post-development impervious cover: structures= 2.09 acres parking lot+ acres roadway= 2.54 acres other: sidewalk= 0.56 acres acres Total = 5.20 acres post=(total post-development impervious cover-A)x 100= 47.4% * The area subject to the criteria may vary from locality to locality. Therefore, consult the locality for proper determination of this value. STEP 2 Determine the average land cover condition (Iwatershed) or the existing impervious cover(Iexisting). Average land cover condition (I,....r.hed): If the locality has determined land cover conditions for individual watersheds within its jurisdiction, use the watershed specific value determined by the locality as 'watershed- 0 'watershed �o �•• Otherwise, use the Chesapeake Bay default value: 'watershed= 16% rr wr Page 35 of 53 ANS PERFORMANCE-BASED WATER QUALITY CALCULATIONS Worksheet 1 page 2 of 3 a„r Existing impervious cover(Ip, r;„g): Determine the existing impervious cover of the development site if present. Existing impervious cover: structures= 0 acres AIN parking lot= 0 acres roadway= 0.13 acres 41.11 other: x.. acres = acres Total= 0.13 acres 'existing=(total existing impervious cover 4-A*)x 100= 1% * The area should be the same as used in STEP 1 STEP 3 Determine the appropriate development situation. MIN The site information determined in STEP 1 and STEP 2 provide enough information to determine the 4141 appropriate development situation under which the performance criteria will apply. Check(V)the appropriate development situation as follows: Situation 1: This consists of land development where the existing percent impervious cover(lexisting) is less than or equal to the average land cover condition ('watershed)and the proposed improvements will create a total percent impervious cover(Ipost)which is less than or equal to the average land cover condition('watershed)• MIN "post 'watershed 41i Page 36 of 53 "' PERFORMANCE-BASED WATER QUALITY CALCULATIONS Worksheet 1 page 3 of 3 Al_Situation 2: This consists of land development where the existing percent impervious cover(-existing) is less than or equal to the average land cover condition (-watershed) and the proposed improvements will create a total percent impervious cover(Ipost)which is greater than the average land cover condition (I watershed)• .rr 'existing 1.2% <'watershed 16.0% ; and Ipost 47.4% > 'watershed 16.0% Situation 3: This consists of land development where the existing percent impervious cover(Iexisting) is greater than the average land cover condition('watershed) 0 'existing 'watershed %; and AWE Situation 4: This consists of land development where the existing percent impervious cover ('existing)is served by an existing stormwater management BMP(s)that addresses MIS water quality. If the proposed development meets the criteria for development Situation 1,than the low density development is considered to be the BMP and no pollutant removal is required. The calculation procedure for Situation 1 stops here. If the proposed development meets the criteria for development Situations 2,3,or 4,then proceed to STEP 4 on the appropriate worksheet. MIS Page 37 of 53 Riverside Village Phase 1 Worksheet 2 page 1 of 4 Summary of Situation 2 criteria: from calculation procedure STEP 1 thru STEP 3, Worksheet 1: Applicable area (A)* = 10.96 acres Ipost=(total post-development impervious cover_A) x 100 = 47.4% 'watershed— o or 'watershed 16% 'existing= (total existing impervious cover_A*)x 100= am 'existing 0.0% <'watershed 16.0% ; and 'post 47.4% >'watershed 16.0% STEP 4 Determine the relative pre-development pollutant load (''pre)* Lpre(watershed)_ [0.05 +(0.009 x Iwatershed)] X A x 2.28 (Equation 5-16) where: Lpre(watershed)= relative pre-development total phosphorous load(pounds per year) 'watershed= average land cover condition for specific watershed or locality or the Chesapeake Bay default value of 16%(percent expressed in whole numbers) A= applicable area(acres) Lpre(watershed)= [0.05+ (0.009 x 16.0%)1 x 10.96 x 2.28 4.85 pounds per year Page 38 of 53 PERFORMANCE-BASED WATER QUALITY CALCULATIONS Worksheet 2 page 2 of 4 STEP 5 Determine the relative post-development pollutant load (Lpsst). Lpost= [0.05 +(0.009 x Ipost)] x A x 2.28 (Equation 5-21) where: Lpost= relative post-development total phosphorous load(pounds per year) am Ipost= post-development percent impervious cover(percent expressed in whole numbers) A= applicable area(acres) Limit= [0.05 + (0.009 x 47.4%)1 x 10.96 x 2.28 = 11.91 pounds per year STEP 6 Determine the relative pollutant removal requirement(RR). RR= Lpost-Lpre(watershed) RR= 11.91 - 4.85 7.06 pounds per year STEP 7 Identify best management practice(BMP) for the site. 1. Determine the required pollutant removal efficiency for the site: EFF= ( RR/Lpsst)x 100 (Equation 5-22) where: EFF= required pollutant removal efficiency(percent expressed in whole numbers) RR= pollutant removal requirement(pounds per year) Lpsst= relative post-development total phosphorous load (pounds per year) EFF= (7.06 - 11.91) x 100 59 % Page 39 of 53 .. "' PERFORMANCE-BASED WATER QUALITY CALCULATIONS Worksheet 2 page 3 of 4 2. Select BMP(s) from Table 5-14 and locate on the site: BMP B: Bioretention filter .. BMP C: Bioretention filter BMP D: Infiltration Tank BMP E: No Treatment 3. Determine the pollutant load entering the proposed BMP(s): dr Limp= [0.05 +(0.009 X IBMp)] x A x 2.28 (Equation 5-23) where: LBMp= relative post-development total phosphorous load entering proposed BMP (pounds per year) IBMp= post-development percent impervious cover of BMP drainage area ,,, (percent expressed in whole numbers) A= drainage area of proposed BMP (acres) .. LBMPB= [0.05+ (0.009 x 60.1%1 x 1.45 x 2.28 1.95 pounds per year LBMPC= [0.05+ (0.009 x 57.3%)] x 0.79 x 2.28 "' = 1.02 pounds per year LBMPD= [0.05+ (0.009 x 55.8%)] x 6.47 x 2.28 8.15 pounds per year . LBMPE _ [0.05+ (0.009 x 31.7%)]. x 0.73 x 2.28 0.55 pounds per year Page 40 of 53 me PERFORMANCE-BASED WATER QUALITY CALCULATIONS Worksheet 2 page 4 of 4 4. Calculate the pollutant load removed by the proposed BMP(s): .r Lremoved= EffBMP X LBMP (Equation 5-24) where: Lremoved= post-development pollutant load removed by proposed BMP (pounds per year) EffBMP= pollutant removal efficiency of BMP(expressed in decimal form) LBMP = relative post-development total phosphorous load entering proposed BMP(pounds per year) LremovedBMPB= 0.65 x 1.95 = 1.27 pounds per year LremovedBMPC= 0.50 x 1.02= 0.51 pounds per year LremovedBMPD= 0.65 x 8.15 = 5.30 pounds per year LremovedBMPE = 0.00 x 0.55 = 0.00 pounds per year 5. Calculate the total pollutant load removed by the BMP(s): Lremoved/total=L +L (Equation 5-25) removed/BMPB removedBMPC+... = 7.07 pounds per year 6. Verify Compliance: Lremoved/total ? RR 7.07 >_ 7.06 rr Page 41 of 53 a :r : I I i I Ix rn \ - 0 0 \ „. _r, \ • -, I .• -41111 - I- r, 0, , \ i h ch CI o sso+ _ _ -„„ — — —j — — — 111 II I � —I j I>I 1 1 \� — — I .. f I ! I-- ,-,---— f_ j .., _,...,_ 1 , ,,,, T , — 1 • i I— : e _ . WWI • 70 0 saoodS ,9Lx,6-5L \ (J •\ v-_ - ..; , 0.. , z _..e,"Alijtll°: \ \ \ _ \ ■ Design VSWMH 3.108 O 0 o a > - < m < 0 a co - (n . CD■< -'' - -S 0 .- 7 Q - a II -. a v _� CO (D N fl CD X N <_ Q - N Q fl O• X ^ a �, £ X 0 D CD a -• �. 3 -I 3 —1 ° — O Q• ' • Q Q 5 Q X Q 0 -' N D Q `. a��' < Z .-. .-. I < O X II X Q O II . ai `. .-. I * Q .� -,' 0 CO v ° 0 o° N o W . 1° p p v (5)rn w of N o (rl 0' (./.) -, te O 3• - C CD cc CD A N O 01 G) MN "" Riverside Post-Development Type II 24-hr 100yr Rainfall=9.10" Prepared by Shimp Engineering, P.C. Printed 12/10/2014 HydroCAD®9.10 sin 07054 ©2011 HydroCAD Software Solutions LLC r Stage-Area-Storage for Pond 10:BMP D Elevation Horizontal Storage Elevation Horizontal Storage °` (feet) (sq-ft) (cubic-feet) (feet) (sq-ft) (cubic-feet) 334.00 9,768 0 339.30 9,768 33,541 334.10 9,768 391 339.40 9,768 34,249 .r 334.20 9,768 781 339.50 9,768 34,951 334.30 9,768 1,172 339.60 9,768 35,645 334.40 9,768 1,563 339.70 9,768 36,333 334.50 9,768 1,954 339.80 9,768 37,012 .r. 334.60 9,768 2,344 339.90 9,768 37,682 334.70 9,768 2,735 340.00 9,768 38,342 334.80 9,768 3,126 340.10 9,768 38,992 334.90 9,768 3,516 340.20 9,768 39,631 335.00 9,768 3,907 340.30 9,768 40,256 Ami 335.10 9,768 4,359 340.40 9,768 40,867 335.20 9,768 4,860 340.50 9,768 41,463 335.30 9,768 5,392 340.60 9,768 42,041 mi 335.40 9,768 5,949 340.70 9,768 42,598 335.50 9,768 6,527 340.80 9,768 43,130 335.60 9,768 7,122 340.90 9,768 43,631 335.70 9,768 7,734 341.00 9,768 44,083 w 335.80 9,768 8,359 335.90 9,768 8,998 336.00 9,768 9,647 336.10 9,768 10,308 .. 336.20 9,768 10,978 336.30 9,768 11,657 336.40 9,768 12,344 336.50 9,768 13,039 .r 336.60 9,768 13,741 336.70 9,768 14,448 336.80 9,768 15,162 336.90 9,768 15,881 ,.s 337.00 9,768 16,604 337.10 9,768 17,331 337.20 9,768 18,063 337.30 9,768 18,797 my 337.40 9,768 19,534 337.50 9,768 20,274 337.60 9,768 21,016 337.70 9,768 21,759 ' 337.80 9,768 22,504 337.90 9,768 23,249 338.00 9,768 23,995 338.10 9,768 24,741 'm 338.20 9,768 25,486 338.30 9,768 26,230 338.40 9,768 26,974 .r 338.50 9,768 27,716 338.60 9,768 28,455 338.70 9,768 29,193 338.80 9,768 29,927 ®r 338.90 9,768 30,658 339.00 9,768 31,386 339.10 9,768 32,109 339.20 9,768 32,828 .r Page 43 of 53 Storm Sewer Calculations Storm Inlet Drainage Map VDOT LD-204 VDOT LD-229 VDOT LD-268 VDOT LD-347 a Page 44 of 53 cn 00 /, ,7 .---;'` '_ {, �• / 7 • ' ' . o o I _ ---''- —/ / ----� \ _ I—IP I _ __ — — , _ -.._ _ - , i /I 7i Tip i i o a / ' /I / I / r o \ \ Ar tee// / r di i 11 Mr i -...._ a) cti ] q 'r i Ill_ I A41 ries‘,' 1 I g 5. \ \ tri a • `-?`""-• . " — i_a.. '''' 10 1■.0 I 4 ' a :::.?,•:, _v 1.--.-..._.,-- .1-::- - .:-.-:•.L -4 as p;,,,' t w iv 0::,,zr-T- ... -......t71:_:-._,- ....,- ,:t mg, &,,,,, 4. , :4 . J-- -.-.-,, f_- ...:z 3--.-,:_-,f7 , „ 1 I g -—---1._ I ;§ =7-3.41F*:--: - .-:-: - • - ..-.. fiA liz' 'Igi IM7 , _ _-- i .,.1. _ _ =gip -...■ IMIN 4 i gi, ii;' ` g ' ?z, 0 �, / / / L ivi I/ ;/ //- , , , , , ,1.3 4, , , /0 Pifiliimmli �/I I , / �. , I I .Ir1.I , / / / t i � E 1 J‹.. . I I I w ® M , / ,,,..„,rl� I / �• • �J I //,1 ', // I �/ I C 1 ( / / ( 401161 i A. z' lw ' f*e_„...,—torle°‘ 'sor ma11111P0- C74 Fri 3 / , , i I 1 / -, iillik, ALT0/,',./ --',0-'-'-'4'■- P" . IP, 6Mk i• r//' p . . ., , 1 r+/ I : kII11i ,73. l 1 ,•°— I / .. /� it ��, 1IPPiii II I ' .I �0 �4 ;IS�:nj.,, / / I ii / 1� I Il Ill�j �► I� �s " / � , /y , I CD o 4 IIsi..- 4 l# 1 . % 1 %-� -�, i' 1IPiJi,r r �� I �-�- ' 1111 �,ld i c ,,... vf,„,. ::F4071, /F, 1 .: Og // 1/ , d) !:',N it/ / I, r I ° ....- ---4_14, 1 rffi "'" —1 • i Ot .•,--,,, It 1 -- ___ iff 4:///-/// I A AO ;fA,I 0,14 /1, 1 . I, : ' 1 / \) : /i dP Al '44114 ,,, , A At..1.;--...-- , A , 1 , , , 1 < „„• .- \k,„\,.,,, ,;, f,',-,1 / \ N \ 4,......„. .;:?f,r...... I LO _o _ -. --. ..4,--.,.A,Ay, - . / to- .1N„ri . ” . N :,,,, ,,,,__-,.,,, / tk,....%, wig% VA ( if , „ ! i ,..... ,,,:,.t._,.....r 11 ,. tz, rt ' 114i k, i /P7 1 1 a(D NN 4/4.4,444 j / / N, (PC' --.. \ -'' 44k''`.7*; .., k,,,,.. / / / ■-, iiii / 11 I ' \ II — ) K \ +.-\ - 41 .-'6aN,,C f \. - / 0 / ,,, 4111111P1V / ./ e-r/t5-\/ -c-----/--)..\..-N7■,,,,-1--- A����� / / / / / ��.. / / / / / / 1/ I ,• I / / v_ 1��� . J1,‘< / , I ■ U7 A A W W W N N A W N ^ ` D CO D CO D o 00 a `2 / \ `� 1 / 1 U1 F+ W N A F' ut A A N N N N 00 CO In I /''', .....4 \\ `�!• 1 , \ ... O 1O W Q i-+ 1.l1 F+ 1--• 01 I--' 00 A N \ ,'I W N F+ W O N O N N 01 N lA W A A 1p0 6 •I' \\ \ � � W 01 N N 00 V W W 01 0 A W A \ \ \I \\ 1 Q1 N W O V7 t' V N N N O N F+ I-+ O O � � \ \� `\ �.z..,,,„„ \\\� \ \ O N D WI-+ O IT O 1.-, N N 8 O V O O O .13:, `{ \ A V V V 4 V00 W A W N W N N A N t0 N N 1--' G+ \,,e A 01 pp 'CO p N 01 p N U.! N W V O O O `-yl�\ 000,1 al l0 01 p 01 U1 1-a F+ N W / \ \ a ao m m ;0 l0 01 0 ' A 70 /- V N l0 r 01 O O O .' A 1-+ I-+ a, p A O O N / �7 ._111 J-0 O W 0 w W fC 0) lAj1 O O O O O O O O O O O O O O O O V N l U1 V V A O l0 O V lU1 CO V O 00 0 n -. W lr !-+ O O O O O O I--+ O O O O O O 0 1-) i-+ A V N l0 C Ol N l0 01 N A Ut N N 00 01 A C A A W l0 01 UI 1--+ 01 W 01 O A l0 *- - 5 aTim _1 O 0 0 0 0 W W W D > > D', > ,DA D Structure 6!(4 N .1 cm A D y A w N 0, n, co 0) 9 y Number C- CD 5• . U) °I 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 m r a r r N Inlet Type a w w � w w w w w w w w w w w w w w YP *;CO CO N C) C) > O Co C) O W O CO C) CO C) CO ' -h m • � 0 N rn rn L co co w a> 0) rn CO rn 0) rn rn 03 Curb Opening n < N — 0 O0 00 o 00 00 o O O o --• o A 0) 0) - A ow 01 0) w 0) A A w CO o 00) A A Catchment Area 3 - CD 7 00 O O 00 00 o 00 00 O 0 o O • w A �I :i 7.4 - aD 0O CT :I oO ix bo o> : 00 :i CT Runoff Coef CO "I �1 N "I A O cm co v CA w O CO CO O N o O O o 0 0 0 0 0 0 0 op O O O O r- O in 00 w O �I N N A N N -• A in -a j CA CA W 0) 01 CO N 00 Ca) 0) N 01 G) 0 0 0 CO N) CO 0 G A A "I A "I A �I A A V A A �l A "I A A .I A A �I A "I A v A v A ,oo IntenSl 0 0 0 in O CT o it Co O CT O O CT Co CT Co Co Cm Co Co 6 O CT O 6 O CT O 7 `y 3 .... 1 wNO) CAN - -a000Tw0 — Ow -- O -, o0w — wlv -a000 0) bo � b) i7, A iv W :1 � CA O bo ib io iv :I CO A "4 A 01 iO CO • • V• "I A �, CO Q Catchment CD A CO �I CA O CO Q) N O CO w co w co co ■A O v CO - V O Co v 0 CT CT O Cn O OCTOOOw "IACOCOw00oCON "ICnOCANC7t OCnvOC)) w E CD C) y o Q carryover 3 s C d Cr. 03 NCAwN - - 00O0> 0 — O03 - 0 — OOw -A03 N - 000 ._ 0 ACO "4CD) OONOOw) NO- (0 W 000 W O 0-0—JJO -- "4Ca) "4001010 m � QTotal �► O O CT 0 O O w V A CO CO w CO O CO N "I CT CA C)) N Cm O CT "I O O) w " O O 0 0 0 0 O O 0 0 0 0 0 0 0 O o o O O o 00 00 0 00 0o O O o o N�Mannin sN ..A ...1 -, ....% ...a O) O) O) 0) 0) a) C)) 0) 0) a) O) O) 0) 0) 0) 0) 0) 0 0 0 0 O O o 0 0 0 0 0 0 0 0 0 p o N N 0 0 N 0— 0— N 0 0N G40 0-a _,6 ob O 0 T 0 A 0 0— -•0 0 -3 w- Gutter Slo e w 7v CO Cr) G0 0 0 0) 0 0 CT N) 0 CT 0 0 CT 00 0 0 00 00 0 00 00 0 0 P O O W 0 N N N A N N N N N N N N N N — A Pave X-slope G) `' N -4 01 0 0 0 CT 0 0 0 0 0 0 N N 0 N 00 0 0 00 00 0 00 00 0 O O o o •0°0 w °w co co 3) o co o 0 0 CO° 0 00 o °w U, Gutter X-slope Go w w w ca w w C.) w ca w w ca w Cr) w w CA A - N cm ,Total Gutter Oa Co• - - o A N °)Spread o i P P N o Depth at Curb N "I CT 03 A 0) 5 CD a _a _ _ " _a ..a 0 0 0 co co co O 0 o o b 0 0 % Efficency o e• o 0 0 o n CD 0 w N O O O 0 Z `G A 00 0 CO 0 o y 0 Q intercepted O0 A GJ V 0) 0 0 co co co O 0o OO 00 00 0O oo v0�) 0 Q Bypassed CD 0 o o o o O 0 0 0 co co co co co co O co o 0 0 0 0 0 0 0 0 0 N N NN -a -iN -a 00 wivwN - -. 00 91 Midpoint Depth CG) A) CA N A O CO — O w CO CO -x O o -A ' 0) - CO "I C000Oo 00 0000 00 0 0 0 0 0 0 0 0 N W (71 T t 0T T T T T T T T T T t T 6 6 T t T t a N CurbHei Height o o 5 m N O 0 0 0 0 0 0 O 0 0 0 0 0 0 0 0 0 0 o O O O O A Ca W iv N iv Cm A i:a N CT W 0 0 Cm Ca CA A w iv -A rN,) D/H ? CT w N) A CO O -.1 -, 0) 01 CT 0) CO N) CO CO W -A N) — CT A `G 01 w A N w — "IN -. - Jw00w . - 00•c0 w 6 6 .A �I iv iA O iv 6 6 �I 6 W CO w �I 6 6 iv CO 00 A Midpoint Spread A A v A 0 - A -. -I - - N CO 00 0 01 C.) A 01 N) 0) C,.) A 0) 0 C.) w. n MO) W u) V MW O NN N OO) N 1- N Mf0c- N (a0 N. O M V M MN — 0 N N 0c- M .- V 0 <- 00 c- 0 — .- C'1 -- 0 c- c- c- 0 0 0 O O O O O 0 0 O 0 0 O 0 0 0 0 0 0 0 0 0 0 0 O 0 0 0 .O 11 0 0 C 4 4 LL C . N 0) (C a I" (136 .- V (0 V M W M m n r n O N M N VV m N V (0 V W m W M M 2 ,- N O O 6 V u O 66 0 46 W 666 0 u 6Y- 66 .- 6 W ' N n Sal To 640 N W 0 T- 0 W OW N .— W W '° u - .- o V (000 0. � .- 0)� ' 0) W (O N •-- Y- .- (A CO C' •- (O (O O) N (O ' e- .- N . .- NNN .,(.. . 0 J V u) (0 W W 0 0 0 00 W LOW N 000 (0 (0 (0 (0 W W W W W CO N N a 0 Orr M ( 0 ? . 0 0 0 0 o N ° o 0 0 0 0 0 0 . 0 0 0 0 0 0 0 .- (O 0 r O N 7, W r r m W O O N O 10 7 (� O W W > NN .-- O .- .- .- MN N OO O Nr- . N . ,- 4 .- ,- 6 .- .- W OO C co 0 Nme N 0 co P O O _W CO CO CO m CO CO O CO O CO CO N V (0 N N CO 0 W N . M M V 0 W 1� N N (0O V N O W NO) 0) W NN0 (0 W COMM `-. m W m D W 7, O W m Ni m M n p 0 - M W N C V u (0 CO . N co co . m ,_ V ,_ '— MNN OM V V N (n N MOW QJ � � a .(C) AIN 0 WO N O 0 NU) N MO 0 000 V N 0 M 0 0 (0 0 WOO _ N O W CO M 0). c— h O (0O W N W mN (O (0 CO N W O �+ r r r r CO COW) (Wc) (Wc) (O O) (n (00 WC• V N. M M M N.y� V .- N N (0D (([ Uj 0 V 0 O M M M 3 C > _ MM M M MM M MM M M c•)C MM M M M M M C M M M Q. 0 .9w E .a.11 0 M O V N 6 N V N M (0000) N 666 V V NOWT- 00 I+) n O V 0N) M N (00 U N O.- 004 W 06 (O Oi (aO d V 0) OO N cc' .- .- 66 66644 .- O 646 0 m V V M M M M M M M M M MMM M M MOW) (•)) M (•W)C CMM N 5 C W . N• N 3 M ooa111. ,C/ V O (0 W W W V 0 V M O O W o N O V M O W M oo ,C ` m V 0 M 0 '- M N O V mv. ..0 - ..,.. M W 00,0m0 0WO .- ----. V W m W N O W OU CU C' V V 0 Im w m aO W N 0 - O ix N LL E M W N 0 O W W 0 W W W O W N 0) N O V N +1111 0 `W (0 () V W C O C O N W W W W N W C O N N MN W O O N N W M O U I N N a.4 L 44 6 W W CO CO 66 CO 66 (O 666 66 666666 U) 666 N N O N M O O O O O M W O N ) 000 0 l� O • m O N N O N O M 0 N 0 N 0 0 V O � N 0 — - 0 - 0 0 . • V W W W — AM J C f0 t0 O (O ui ui M (0 (0 (0 (0 (O (0 (0 6 (O 6 u) u) (0 (0 6 (0 (0 O O N N L Cl)00 E F F- .- `' 2 N C CD t N m N O O 6 (0 V 0) 0 m N N 0 00 M M M N W N to N m m O E c m o W M () O m m V N .- N V co N V N. N CO W O W u) u U) u 41111 o 0 .- , O O 0 .- op o .- O 000 do 0000 . . 666 fx mU a .< 0 4) (0 CO 0 CO N 0 W V m CO N U)M 00 M O V W N 0 0 oo U) m(0 W M u) 1- (0 V VP.- N N V NN N .— O V (0 W .- 0 7 w 66 0 d 0 O 66 66 666 0 0 d 6666 d d d c cQ c 8 0 01� N N (0 N NO MO OWN N W M W OOmm 0 N o w V M V N N W I� W W M W W O N W W M W M W N W N y cm 60 0 d d d 66 66 666 d 0 0 6666 0 d 'o ''a O 2 0 V W co CO V 01 m 66 W M W V V m O � m V V 0•M V .- 4 N N CO NM N V 0 N N M W D N .-L V .- O O O O O • O O O O O 6660 p O o U 0 T 4111 O Q p _ C Q 0 a N N � V V M M N N MNc- NcmW P... W uq V MCy LL LL W 0 0 0 0 0 00 0 0 m m M Q Q QQQQQQ Q Q ¢ Q o ,y 0 M N N n (0 Q y 03 < co m N CO N _M N_ O m W n co(0 Q V M ccyy Q LL LL W 0 0 0 0 0 0 O D 0 m m Q Q QQQQQQ Q Q Q Q 0 LLao m 0 w U) _ ƒ L) } 2 41111 \ \ CL o r > w e N _ ' a o o f e m , N w § • > N N N S LO o ci ci p = CO -. 2 w w > _ . • • B % > m m m _ O < 2 w E p 6 c2 \ /0i L 0 _ m E m CD MI " 0 w = 2 2 Q £ G g G S g L d • 0 _ @ 2 2 7 CC vt _ .> m m ■ 0 cc 0 2 U q c 2 / wd . r _ ' 0 q o G G k - tri a a 2 © £ ® % 0 m 0 0 M e g o o C 0 U) _ o _ N N m o e 0 e < o 0 o g 0 A _ o g o � ? o a d 2 m m _ < h o 0 o e \ 0. @ totomo ® o 0 0 . J 2 < b ' 0 I > r -n 3 n 0 7d o - Ca C CZ Z �G W N m -J 01 D OA � y O CO )7* 0 A co W W N 0CDDCOO "4CDco 4. W NBC = y. O CD cr o. CD o 0 oa W CO CO Wp W CO CO CO W CO W W () W W W W W W W (C,,al� W W W W Cn C n• r ? A 0A A AA co A A A W N CD00') CTAA 040400 mC- * 0 w CO CD O) CO CO CD CO -. CO 0) N -A 0 W N N O CO -• O O co N -- V co A v < N N .. O CD N O V Co CO 0 -' 0 • N Co Co 0 O in O Co O V 0) A OD V A V 0) 0 CD o O al 000 O O W W N V CT V CO A O O O O A V CT W � 00 (T CO O a) Q (D r ..... � _ _ A N - N N CD IV N 0 O fJ N N N N Cn IV in O N N N N N) N N 0 Co 0 Co CT O O D co (Cl 0 0 CT CT (Cl CJC CT 0 CT co (T CT 0 CT CT O O O O O O O A O 0 0) N W 0) W co ((j W CO -A CO CA -A N A A CD CT CD („3 CO CO CO.-. A (O W O -A CO V CA 4. O W A • in - 0 W Co Co CO to 0 6 W• Co Cb :-4 v `n A O CT 0) CO CO A CT O Co A 0 O O A V 0 A co O 0) CT CO A CJ) �' CA -i N 0) 0 -, CD -� co N N U W - ' A A N (T CD CT C D CO -' -a v g — 0) CO co A 0) CO Q) O CA CD A A CD -A O W V W O W O N r bo AGp OW0 V O 0 00 -, 000 CD � D W ONOOO) 0000 00v ACn N v 00) -aCW)'� O V O O O 0 0 0 0 O O O 0 0 P 0 0 ° 0 0 0 0 0 0 0 N 0 O OWOO v OW0 '0 Q0j CVO CO N CO ON N O � CN)1 NA 00V W Nv0 OD (n C 03 0 , W o CO o 0 CD CD 4t 0 o V o o co 01 co 0 o 0) o Co \° CO o o ag ag o c ag o o e' o 0 0 0 c ag o c 0 e 0 0 0 0 0 ° 0 0 _ p P O O _ O 0 O O O O O O O 0 O O _, O 0 O 04' Co A W N o O WOV CO W v 0)) OA0 Co COTcoopoO "40 N00CD 2 CO O 03 N 0') D O0) co 0 CO V CO A O VT _' 00 p "' V V T N co A W A 0 A O) Co co O A O CT (T 0 0 A 0 N N) W CT co co — N co N (T V N A CA - N A -, N A A W W 0 co 0 co CT 0) O) N A V V A CD N W V V V N 0 (0 : - O O Co -. Co 000 CO ZS G -a NJ CO CO V n CO V A (T — V O N V N CO N3 -A V — O CO 0 V - ° (0 -► Co O CA C) N N (T (T -X 0) CD co A 0 CD A A 0 0 A CD -a D -4 N O O O O O O O 0 O O O 0 0 5) 0 0 P co co co 0 0 0 0 O O O • p � • C) .0 aCD 0000 p�� A � _tg 88.3 8 g A A O N ^4 O C00000 A 000 V CD 000) 000)) 000)) COOD 4% CWOOWO � o ,A O co 0 CO CO CO O CT O V N co co 00 CO V 0 O CO 00 V co 0) (JC! A N co W CD O) co -. 0 — co — A A CT 0 (o C j co (00, 4% -.. W V A W W A Cn -a Co (O CO O) 00 O W Cjt W 00 is Q A CO CO A W N O A O CT V W W O CD -+ 0 +� W A - O N V O CD V O O W CO co CDN -a CD CO 00 CO - N N CD CT N V A -4 N — A A W co (Cl 0) 4% -A 01 V V 0 A N V Co V N CT -- 0 0 -• Co -• (0 00 O CD < V Cn V CD A -a CT V N V -+ NJ -A V -A 0 CD CO Cc) CO CD O) CA N N (T — CT 0) Cn A CO A CD O A O -A CO A V — - -+ - - A 00A � - 0-7 CO CO V co C0 co O 00 - 6 CO CD V 0 CP CO -A —A -a - cn• CD V N O O V -a 6 W A co co Op 00 V A CO CO N W C ✓ -+ O • N Cn CO 0 — -a W CD V N 0) O V CO V Co O C_ C p coO O OO OO CD c) CD 0000 _ fin. p O O � -• O N -' OO W SoOOOCCDCCDD � NCO -' a 2 O IA) O W 0 D A A p p 0 CO V 0A) 00) A c0D W 00i t- OD V O (D CT A O O _, N ? N V -- 0 0 W CA CA 4 O N ? CO O 0) CO 03 N co A N COO 00 0 0) .AA 0 0 W A• CO CD p p 0 O O O 0 O O O O O 0 O O 0 0 0 O CD 9 O l N W v CO 0 W CO 0 O O co N 0 W w CO ^4 CD W -a 0 Cn- o. CO � (NT A COO (D -a co CDN co O 00 ONCWJCA V (D CAC v O O0 0 O O� O N O 'nO) CD O O AO Ow HIV NEl N A OOCD 2 • N _ O (j Opp 6 N CO p A V O CO N N CD CO 0 CO CO CVT 0 (00 W O O co i WO CO N 0) CD 4, CO CD co 0 A CO N) N A 00 0 V CT OO 0 O co V 0 co O O 0 O O p O p 0 0 0 CD 0 O O O O 0 0 0 0 0 O p _ COT W A CO N W CNT v v W 00)) OWO W OW) W :It. co OD v W O 003 0)) N v ("3 W � � CO 0) (31 � � W � CC31 O N W O CO co C C P 0 0 c O O op O o O O ON COO ON Ao '' CT -� O CO W V al A W (d W V CO CO_ O V 00) N ? (Cl = CD C0 0) 0) 0) co 0 V 0 al O ., O O 0 0 0 a0 N 00 — CPp 00 0000 _, — CO � ..., T W w co COO W A -a N OP A CD CD W O CO V A O VP O CO N W '4' Co (p0 Co N V d. N 0 0) CO O CO N V W co 0 0 00 0 oo (Jl ^4 -a CO V N CT -' O W 0) 0 co V CA O W CO — (CO� Ni CO 00 V 0 co CA CO 0 0 co W CO O ((�� N 2 WA A CO A A co W (JWi A A A A CO CO A A W CO OW) CWT CWD co W A .WP co W 03 m C < E W O -4 O CO O CO N CO CD N N -- CO N N O (O -a ^4 CO CT A N O v cn N CD N 6 A -- 0 O O CO O (O A 'co W Co W C o T N CO) V 0p N Co 3 Co A N V • O N� n (� 0) O 0) CO W 0 CO N O W A N CO 0 CA A CO A CO A W CO CO A CO Cp W co co W W CO W CO CO CO CO CO W CJ W W W W W CO CO CO W CO W W A A A O C (Cl (T (T (T 0 A A A A A A A A CD O A 0 6 A A W CO CO O) V A CO CO CO V CT T -A — CA O O CO 0 C0 N N O V in A iv CD CO CD O CO O -+ N Oo CT Co Co A Co O CD O O Oo O Co N m O A CO O CO O CO O V V CD CD CO N N N NJ -A 0 0 0 00) 0 A 00 < 0) MI (D A CO O_ (T Co.) Independent Reports .. Excerpt from NRCS Soils Report NOAA Precipitation Report .. .. .. .. .. Page 50 of 53 I I N (V N M Co I OZ£ LZ4 OEZ 1 Z 04L LZ4 090 LZ4 096 LZ4 OL9 LZ4 94 9 La N..94.9Z�£. --- - ----- Zo9L p •l Q 1 v I r.Cam It St ec 444 ,gatillt I 344\r e r lI 0401'''s• n Go Q ay,x I 1 _ Q t, I II I --� r,: Pb lot o vUgy o - ° q 0 N g N t Q y Q.3 0 6) LO N X N CI `tip N v, = N N rn .... _0 ti L 4 2 in C 2 Pi i/.i,. ` P, 13°O LL k O — N U- `1 O F., y N o f N t t♦ t.,... •• \N x 1 N N Imo. t.. ,. N O Cl �)a6PU Mn Q v _ 8aa o 0 m E W O N N I . 4104 n : a. oil n M R Ili N z-:::,;( - - 11LZILZa9L _-. .. 23,LZ a9L OZEE1Z4 OEZ£1.Z4 041.£1,Z4 090ELZ4 09621 Z4 0L9Z 1-Z4 4 I F N a ti N (V th 0 III a Custom Soil Resource Report a Table—Hydrologic Soil Group Hydrologic Soil Group—Summary by Map Unit—Albemarle County,Virginia(VA003) ... Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 12C Catoctin silt loam,7 to 15 percent C 9.9 28.7% slopes m. 12D Catoctin silt loam,15 to 25 percent C 0.5 1.5% slopes 71B Rabun clay loam,2 to 7 percent B 14.2 41.4% slopes "" 71C Rabun clay loam,7 to 15 percent B 4.5 13.0% slopes 76 Riverview loam B 3.6 10.4% +ili 79B Starr silt loam,2 to 7 percent slopes C 1.7 5.1% Totals for Area of Interest 34.4 100.0% a Rating Options—Hydrologic Soil Group Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher a a a a a a 21 Page 52 of 53 NOAA Atlas 14,Volume 2,Version 3 06'" Location name:Charlottesville,Virginia, US* nose .r. Coordinates:38.0390, -78.4521 �I Elevation:351 ft* rcs 'A *source:Google Maps "'a..,..• .r 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 +O PF tabular I PF graphical I Maps & aerials PF tabular NM PDS-based point precipitation frequency estimates with 90% confidence intervals(in inches)1 Average recurrence interval (years) Duration 1 2 5 10 25 50 100 200 500 1000 .r 5-min 0.353 0.420 0.492 0.554 0.623 0.678 0.728 0.776 0.834 0.880 (0.318-0.392) (0.379-0.466) (0.443-0.546) (0.498-0.613) (0.558-0.688) (0.604-0.747) (0.645-0.803) (0.683-0.856) (0.726-0.921) (0.760-0.976) 10-min 0.564 0.672 0.789 0.885 0.994 1.08 1.16 1.23 1.32 1.39 (0.508-0.626) (0.606-0.746) (0.710-0.874) (0.796-0.980) (0.889-1.10) (0.961-1.19) (1.02-1.27) (1.08-1.36) (1.15-1.46) (1.20-1.54) .r 15-min 0.705 0.845 0.998 1.12 1.26 1.37 1.46 1.55 1.66 1.74 (0.635-0.783) (0.762-0.938) (0.898-1.10) (1.01-1.24) (1.13-1.39) (1.22-1.51) (1.30-1.61) (1.37-1.71) (1.45-1.83) (1.50-1.93) 30-min 0.966 1.17 1.42 1.62 1.86 2.06 2.24 2.42 2.64 2.82 ON (0.871-1.07) (1.05-1.29) (1.28-1.57) (1.46-1.80) (1.67-2.06) (1.83-2.27) (1.99-2.47) (2.13-2.66) (2.30-2.92) (2.43-3.12) 60-min 1.21 1.46 1.82 2.11 2.48 2.79 3.09 3.39 3.79 4.11 (1.09-1.34) (1.32-1.63) (1.64-2.01) (1.90-2.34) (2.22-2.74) (2.48-3.08) (2.73-3.40) (2.98-3.74) (3.30-4.19) (3.55-4.56) 2-hr 1.45 1.76 2.19 2.58 3.08 3.49 3.91 4.36 4.97 5.48 ® (1.27-1.66) (1.54-2.00) (1.93-2.50) (2.27-2.93) (2.68-3.48) (3.03-3.95) (3.38-4.42) (3.73-4.91) (4.21-5.61) (4.60-6.21) 3-hr 1.58 1.92 2.40 2.81 3.36 3.81 4.28 4.77 5.44 6.02 (1.39-1.82) (1.68-2.21) (2.10-2.76) (2.45-3.22) (2.91-3.84) (3.29-4.35) (3.67-4.88) (4.06-5.44) (4.57-6.21) (5.00-6.87) 6-hr 2.02 2.44 3.02 3.56 4.28 4.91 5.57 6.28 7.29 8.18 NM (1.79-2.29) (2.15-2.76) (2.66-3.43) (3.12-4.03) (3.73-4.84) (4.25-5.54) (4.78-6.28) (5.33-7.09) (6.09-8.23) (6.75-9.25) 12-hr 2.53 3.05 3.81 4.51 5.49 6.36 7.30 8.34 9.86 11.2 (2.24-2.90) (2.69-3.50) (3.35-4.36) (3.95-5.15) (4.77-6.24) (5.47-7.22) (6.21-8.28) (6.99-9.44) (8.11-11.2) (9.10-12.8) ,i. 24-hr 3.03 3.67 4.68 5.54 6.81 7.89 9.10 10.4 12.4 14.1 (2.72-3.40) (3.29-4.12) (4.19-5.26) (4.94-6.20) (6.03-7.59) (6.95-8.79) (7.94-10.1) (9.00-11.6) (10.5-13.8) (11.8-15.7) 2-day 3.57 4.33 5.51 6.48 7.88 9.06 10.3 11.7 13.8 15.5 (3.21-3.99) (3.89-4.84) (4.93-6.15) (5.79-7.22) (6.99-8.77) (7.98-10.1) (9.04-11.5) (10.2-13.1) (11.8-15.4) (13.1-17.3) gm 3-day 3.80 4.61 5.86 6.88 8.37 9.62 11.0 12.4 14.6 16.4 (3.45-4.21) (4.18-5.11) (5.30-6.49) (6.22-7.61) (7.52-9.24) (8.58-10.6) (9.72-12.1) (10.9-13.7) (12.7-16.2) (14.1-18.2) 4-day 4.03 4.89 6.21 7.29 8.86 10.2 11.6 13.1 15.4 17.3 (3.70-4.44) (4.47-5.37) (5.68-6.82) (6.65-8.00) (8.05-9.72) (9.19-11.2) (10.4-12.7) (11.7-14.4) (13.5-16.9) (15.0-19.1) "M 7-day 4.69 5.65 7.06 8.22 9.89 11.3 12.8 14.4 16.7 18.6 (4.31-5.12) (5.19-6.16) (6.47-7.71) (7.52-8.97) (9.00-10.8) (10.2-12.3) (11.5-13.9) (12.8-15.7) (14.7-18.3) (16.2-20.4) 10-day 5.32 6.38 7.88 9.10 10.8 12.2 13.7 15.3 17.5 19.4 (4.91-5.75) (5.89-6.91) (7.27-8.53) (8.37-9.84) (9.91-11.7) (11.1-13.2) (12.4-14.8) (13.8-16.6) (15.6-19.0) (17.1-21.1) "M 20-day 6.98 8.33 10.1 11.4 13.3 14.7 16.2 17.7 19.8 21.4 (6.53-7.47) (7.80-8.92) (9.41-10.8) (10.7-12.2) (12.3-14.2) (13.6-15.8) (15.0-17.4) (16.3-19.0) (18.1-21.3) (19.4-23.1) 30-day 8.56 10.2 12.0 13.4 15.3 16.7 18.0 19.4 21.1 22.5 (8.06-9.12) (9.55-10.8) (11.3-12.8) (12.6-14.3) (14.3-16.2) (15.6-17.7) (16.8-19.2) (18.0-20.7) (19.5-22.6) (20.7-24.1) ma 45-day 10.7 12.6 14.8 16.4 18.4 19.9 21.4 22.8 24.6 26.0 (10.1-11.3) (11.9-13.4) (13.9-15.6) (15.4-17.3) (17.3-19.5) (18.7-21.1) (20.0-22.7) (21.3-24.2) (22.9-26.2) (24.0-27.7) 60-day 12.5 14.8 17.0 18.7 20.9 22.5 24.0 25.5 27.3 28.7 .w (11.9-13.2) (14.0-15.6) (16.1-18.0) (17.7-19.8) (19.7-22.1) (21.2-23.8) (22.6-25.4) (23.9-27.0) (25.5-29.0) (26.7-30.5) 1 Precipitation frequency(PF)estimates in this table are based on frequency analysis of partial duration series(PDS). Numbers in parenthesis are PF estirretes at lower and upper bounds of the 90%confidence interval.The probability that precipitation frequency estinetes(for a given duration and average recurrence interval)w it be greater than the upper bound(or less than the lower bound)is 5%.Estimates at upper bounds are not .r. checked against probable maximum precipitation(l vP)estimates and may be higher than currently valid PIP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical Page 53 of 53 OM