HomeMy WebLinkAboutWPO201500098 Calculations Minor Amendment 2018-02-06 WINTERGREEN FARM STORMWATER
MANAGEMENT CALCULATIONS PACKET
Date of Approved WPO 201500098 Calculations
NOVEMBER 13, 2015
Date of VSMP Amendment #1 Revised Calculations
JANUARY 16, 2018
APPROVED
by the Albemarle County
Community Development Department
Date 214/1,8
File N1020i5000942
PREPARED BY:
COLLINS
200 GARRETT STREET, SUITE K
CHARLOTTESVILLE, VA 22902
434.293.3719 PH
434.293.2813 FX
www.collins-engineering.com
DEQ Virginia Runoff Reduction Method
Water Quality Calculations
Summary:
The following water quality calculations were modified to include the minor increase in impervious areas associated with
the proposed trailway along Sunset Avenue Extended.The trailway consists of 0.36 acres of impervious areas located
within type B soils.
This inclusion resulted in a 0.36 acre increase in type B impervious area soils and a 0.36 acre decrease in type B managed
turf soils in the VRRM 'Site Data'sheet.The impact was an increase in this development's minimum required
phosphorous removal rate.The prior approved calculations required 20.14 lbs/yr and this amendment requires 20.77
lbs/yr. Please note,the approved plan removes 20.79 lbs/yr and the amendment removes 20.97 lbs/yr, both of which
exceed the minimum required.
The additional impervious areas also impacted the minimum design treatment volume for stormwater management
(SWM)facility A. The majority of the trailway is located within drainage area A,where it receives water quality and
quantity treatment. The VRRM 'Drainage Area A' sheet was updated to have an increased impervious area of 0.21 acres
of type B soils and a decreased managed turf area of 0.21 acres of type B soils.The result was an increase in SWM facility
A's design treatment volume.The approved treatment volume was 31,027 cf and this amendment's treatment volume is
31,599 cf.The approved plan provides a treatment volume of 35,231 cf,which exceeds the minimum required.
Virginia Runoff Reduction Method New Development Worksheet-v2.8-June 2014
To be used w/2011 BMP Standards and Specifications
Site Data
Project Name: Wintergreen Farm-Phases I,II &Ill
Date: 1/16/18
data input cells
,„ ,„ calculation cells
• constant values
1. Post-Development Project& Land Cover Information
Constants
Annual Rainfall(inches) 44
Target Rainfall Event(inches) 1.00
Phosphorus EMC(mg/L) 0.26 Nitrogen EMC(mg/L) 1,86
Target Phosphorus Target Load(lb/acre/yr) 0.41
Pj 0.90
Land Cover (acres)
A soils .B Soils C Soils D Soils Totals
Forest/Open Space(acres)-undisturbed,
protected forest/open space or reforested land 0.00 0.00 8.71 0.00 8.71
Managed Turf(acres)-disturbed,graded for
yards or other turf to be mowed/managed 0.00 19.91 38.31 0.00 58.22
Impervious Cover(acres) 0.00 5.57 4.63 0.00 10.20
Total 77.13
Rv Coefficients -
A soils B Soils C Soils D Soils
Forest/Open Space 0.02 0.03 0.04 0.05
Managed Turf 0.15 0.20 0.22 0.25 _
Impervious Cover 0.95 0.95 0.95 0.95
Land Cover Summary
Forest/Open Space Cover(acres) 8.71
Weighted Rv(forest) 0.04
%Forest 11%
Managed Turf Cover(acres) 58.22
Weighted Rv(turf) 0.21
%Managed Turf 75%
Impervious Cover(acres) 10.20
Rv(impervious) 0.95
Impervious 13%
Total Site Area(acres) 77.13
Site Rv 0.29
Post-Development Treatment Volume(acre-ft) 1.87
Post-Development Treatment Volume(cubic
feet) 81,488
Post_Development Load(TP)(Ib/yr) 52.39 Post_Development Load(TN)(Ibv 1 374.79)
Total Load(TP)Reduction Required(Ib/yr) 20.77
•
Drainage Ane A
I
Orslr.p.Area A L.te cov.r own) -
A soils %Solis IC Soils 0 Sobs TGeY Lard Cover Re
F0.ea000.n SPea(Som)
pR ��
'.,Talal ���ti<_..'m� _, _ ----- Pwt DrvrroPmmtTreetmam.Volume lop 3 3159
Apply Runoff Reduction Practices to Reduce Treatment Volumed Post-Develo - - ____ -_--- - --_--
pment Load in Drainage Area P , I
Phosphorus UM*
Volume from Remaining Load nom Phosphorus Mupmrus Remaining
Cr0011 Arse Upstream RR Runoff Runoff Phosphorus Upstream RR Lo*O to Practice Removed By Phosphorus
Prey. UnR lame er Credit Oren acres Practice cl Reduwbn cl Volume Efhclenc %Prectices IM IDs. Practice lbs. Load Its Downstream Treatment to be Ennio ad
1.Vegetate,Roof
1.0.Ve9enb0ROMA,(50,005) taen009,0000005 45%runoff adu00e000 5oT 0.45 000 0 0 0 0 000 000 000 000 '
1.D.Vepel.Ya ROM/2)Spon/s) .ora M agmen 000, 0012 ruroff 00500010011010, 0.60 0-00 0 1 0 : G o
2.,.Snipe D10.14*0,m AiR Sob(Spec '50%dee 0521100,00020100
/0) m00MO0s1100000,50o01,01.00 Oo,velem area 050 0.810 0 0 0 0 000 0OC 000 000
20.Simple OY O0.00/0504,(Spec 25%rano?,volume 0000000, I 3
s0) m0010000acrea 0.000„,0504 for,00,04,1,4 0.25 000 0 0 0 0 0.00 0.00 0.00 000
2.c 8To.oil o)ao 01 Rear Pam ea per ISPs rv011 w ume remucp0n
0000 first ons lex senO crD,ora7(spec r4l mpelawhn eaaal„nn,ened' 0.50 0� Q O '0 0 0.00 '
0.00. 000 0.00
TO Dry 01V1l orFrench Nan/1 0'rulrof wumeree0coon
2 ralene nc rel Dnpemous acres elxonrreved 5 vol veal,,area 0.50 D,OD 0 O 0 25 QOD 0,00 0,00. 0.00
2 e e.ToTo Dry Nell orrFrench Drain/2(Mico- BPh runoff volume reduction
08500,n2)(Spec/9) mervwus eve elannnev nor veal,,ares Oso :9.00 4 0 4 25 D.OD 0:00 0.00 000 j
2 To 5000 Garden rt(Mhcro6 ora000100 M '
00)(Sete*11050ervhousacrva0,00,0,054 r. me reau-00 040 0.00: 0 0 0 25 000 000 0.00 0:00
zp.To Ran GeNen/2(MrFp6o,0YnMn ea%anonroume 00000,
005(50000(0 m0crebaaaadhRn,eMSe 080 000 0 0 0 ' 50 000 :000 0.00 0,00
M,gn aPreaemrel(see -1
2 0 To 0.100,1.10,nes0l9(Spec/S) m0ereb0a soa upured 5050/0 0.00 O OD 0 0 0 0 000 0,00 000 000
2.I.To sl0mwmer eO 00lumen See runoff volume lmucoon
eblate.lon5lspe0 se.Apcewat Ynerw11l aa2.0meaed ,«rcea,00 area 040 OW:. 0 0 - 4 25 '.
3 Permeable Pavement
acres 0,permeable pawmml.
3.11 Permeable Pavenent XI(Spec/T) a mal'(upgrade.)
gP1001001100040me. 45%00ee00b10eree0Gon 045 000. G 0 0 25 000 0.00 ( 0.00 000
3.00.Peme.00000000001a(Specl0 0100M0erme.00 )5%00,00wlwrcradVmon 0.75 000 .0 D,;,.„ 0 25 000 0.00 0,00 0.00
pendent _.
4Grese 40Cnnel
murvOIC.va Unielg ro
e.a.Gnu GlYneI AlB bob(Sp.0A) area cnanne8 1P4 mn011 wiume na.cgo, 0.20 D.OD D 0 D 15 D:OO 0.00 0,00 9.00 I'
Nn arrts0rahnhn9lo press
00,,,.la 20%rvef 0011100.oe0ucti0, 0 20 0.00 0 9 0 15 0:00 9.99 0.00 0.00
mpe1.1o01 anis dm�.,g ro
aD.Grew meas CID SMY(Sp peS) grass 0nmTels 10'rpnpm ea0,0,r.0 010, 0.10 000 0 0 0 15 0.00 000 0.00 0.00
Deaf,005100,1 n rep ro gras0
n ,P4 r.non ro1110e re0uman 0.10 000 0 0 0 t5 000 i 000 0.00 000
mperyo.s acres draining to 7777
4.c.Gn,to pe,e at,Conmo.An.lrOM ga,2.ha0ne l ]016 rvrgll 01100,rcduc0on 0.30 O DO D 0 0 r 15 0.90 0.00. ' 0.00 D,W
sas es cer,pma(w spec 114) 0010 00,0 nngro peas.
ore M.,,.. w%011,0 wluM 000uw0n 0. 000 0 0 0 15 000 0.00 ' 0 00 9:00
mpeltl0rrs via men-,Ing wary �,:�
5 a.Ory Soak 01(Soe0000) 0 4P4 r11,0n rowme red11wo, 0.40 _ 000 0'' D 0 20 000 I Od30 000 000
h,5e0resdren�,1l00,0,0a5IOP4Nn0n roomeredoom, 0.40 000 : 0 0 0 20 0;00 0.00 0.00 0,00
1 ;
bw,rlou0 000./C n,g to en j
5.D.Dry Swale 81(Specn0) " sate moll wlume rm.c0on 0.60 OOD 0 0 0 40 DOD 000 9 00 O.OD
ayesare.Og0Mmnk s0%5,offw11meree11500 060 _000 0 0 0 , 40 000 000 0.00__ 000 __
6 Riorsie0tion „u. , ....
bbatNG0 ass 00im9 b .. 7
Ea.0o0en,Dp ef w 005.5 ebr..Mo, Db,080,5. 40%0110005.dome remrno, 0.40 0.00 0 0 0 25 000 : 000 7 D:OC' 0.00
(Spec/R) , 08,On.mngm h
re m h n 4014 0moff w ume red00M1 0 40 0.00 1 0 0 0 25 000 0.00 0.00 0.00
more eoreen,o9 n rpb
S.D.Se1eYnDm u(Spac W) eo%runortw11me redurnon 080 431W 0 0 O 50 000 DOD 000 -0DO
Nil D0,Ortong to tf
Iwss meal volume,0011100, 0.80 ,.•,`fk00 Q :1 i! tt.;,.� 50 >OW S 0;00 9.09..: 0.99
2.
7.Infiltration
mper.,oua acres draining m - •\�,)IFi
f...i0mitre.un(Specrs) I8000Se1unollvo0mere411Mon 0.50 000 0 0 C _ 25 000 0.00 0.00 000
520.0,0101acres draining 10aining 0,s0%ninon wlume led11mon 0.50 000 0 0 0 25 000 000 0.00 0.00
mpenbus acreto
lD.lnnb.Don n(Spec M) 11nra00n legs:runoff volume redocmn 0.90 000 0 0 0 25 0.00 0.00 000 0.00
turf.ores Menne to,,Rlretb0 se,runodw „
volume reducr.l 090 000 0 0 r 0 25 000 0.00 9.00 000
,• �,a ,i
8_Extended pexontion Pond
0.0.0000 ISp.0n51 050.5000ova000 00t0ED Pre111,0,vol1110e050000, 0.00 0.00 0 0 0 15 000 0.00 000 0.00
wd0005dna 9to ED 0%come 00101000000,00 0.00 0400 O 0 0 15 000 0.00 0.00 0.00
00.E0/2)Specr,S) 0.005,0150010.0ingro0015%0wwffwumerepuc00^ 0.15 000 0 0 0 15 000 '000 0.00 0.00 4
6,0,00.800 91060 05%100054aumere4uwonl 0.15 099 0 0 0 15 090 ( 0.09 0;00.... 0.00
'..Sheonlowto l'OterfOPen Spoon
nmon9 m Ts on
impervious `� 001015eeeare 000 075 000 0 0 0 0 000 000 000 000
Ra.Sheemow to Conservation area OM AIS 520 acres divan tip le conserved 05%runoff volume reduction
Sats(5o.oel) s rorve0000r,o 075 0.� 0 O 0 0 D:DD 000 -0.00 h 000
impervious crew dram,to 50%runoff volume re0u01on
d0Feo space mot,ahem area 0.50 O.li9 4 0 D 0 DOD O.DO 9.00 000'
mnaehve r
s.D.S000t loem0onsemaon Area with CID 524 eves en nng to conserved 50°k meagre 05,110 on roume
sa5(5peca2)
m00,100dr r r 050 000 0 0 0 0 9;00 000 0.00 0:00
urvou0a00es 0nmupm 50%runoff440,0*r0541100
Re S0eamwv,ove9ddBFEMlsmpRV free sing ror vvaee 0050 050 0.00 0 0 0 D 000 0.00 D:OC 0.00
Scar G Compost Amended 81010 000.)Spec 50'4 runoff 61.2015,00200¢ 11
02004) 8,5.0051010109105115 0100 ror1r0,100.1.0 0.50 000 O 0 0 0 000 0.00 i
0.00 9.00
TCTA a1oERVI0U3 COVERT E ED jac 0,00
-.. TOTAL TLRF AR REATED(ac x-00 i - ._
-: TOTAL PHOSPHORUS REMO L EQUIRED O 5 E(05 37
.__.._ I TOTA U 0 F R0000 ON N D2 7( I -
PHOSPHORUS RL9101/Al FRO UNO F REDUCTION PRACTICES x 0 A 050 55v--.
......... -_ ........_a .__.._ 1-- ..... NITROGEN
I SEE WATER WALITY COMPLIANCE TAB FOR SITE COMPLIANCE CALCULATIO!' T- - --'f- - -
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SCS TR-55 Calculations
Summary:
The following water quantity calculations were modified to include the minor increase in impervious areas associated
with the proposed trailway along Sunset Avenue Extended.The trailway consists of 0.21 acres of impervious areas
located within type B soils within the approved SWM facility A watershed.This 0.21 acre increase in impervious area,and
equivalent decrease in managed turf area, resulted in a change in the weighted CN value for subarea A.The approved
weighted CN value is 68.1 and the amended weighted CN value is 68.5.This is the only change associated with the
following calculations.The shaded areas in the SCS TR-55 manual's worksheets 2,3 and 4 highlights the values that were
modified. In the routing calculations,the weighted CN value was the only input parameter modified.The end result from
a water quantity standpoint was a mere 0.02 cfs increase and a 0.48 cfs increase during the 1-and 2-year design storm
events.These flows continue to be less than the approved pre-development flows.Also,the amended 1-yr.flow
continues to be less than the previously approved maximum peak flow rate calculated in Virginia DEQ's 9 VAC 25-870-66,
subsection B.3.
U.S.Department of Agriculture FL-ENG-21A
Natural Resources Conservation Service 06/04
TR 55 Worksheet 2:Runoff Curve Number and Runoff
Project: Wintergreen Farm Designed By: FGM,PE Date: 1/16/2018
Location: Sunset Ave/Redfield Rd/Wintergreen Ln.Boundary Checked By:SRC,PE Date: 1/16/2018
Check One: Present X Developed X Shading:Denotes Changes to Approved Calculations
1.Runoff curve Number(CN)
Soil name and Cover description
Drainage Area CN(weighted)=
g (Cover type,treatment,and hydrologic condition; Area Product of CN Calculated
hydrologic group CN total product/
Descriptionpercent impervious;unconnected/connected (Acres) x Area total area 'S'Value
(Appendix A)
impervious area ratio)
DA A Impervious Areas 98 1.15 113.1
B Woods in Good Condition 55 18.32 1007.4 58.4 7.12
(Present)
Lawns in Good Condition(75%+Groundcover) 61 6.38 389.2
DA 6 Impervious Areas 98 0.40 39.4
(Present) C Woods in Good Condition 70 2.51 175.7 73.9 3.53
Lawns in Good Condition 74 3.06 226.3
DAA Impervious Areas(Includes Ex.Imp.Areas to Remain) 98 5.18 508.0
(Developed) B Woods in Good Condition 55 3.64 200.2 68,5 4.61
Lawns in Good Condition(75%+Groundcover) 61 13.98852.6
DA B Impervious Areas(Includes Ex.Imp.Areas to Remain) 98 3.29 269.8
(Developed) C Woods in Good Condition 70 1.77 145.1 82.0 2.20
Lawns in Good Condition(75%+Groundcover) 74 10.88 892.1
DAD&E Impervious Areas 98 0.00 0.0
B/C Woods in Good Condition 62.5 8.16 510.0 62.5 6.00
(Present)
Lawns in Good Condition(75%+Groundcover) 67.5 0.00 0.0
DAD Impervious Areas 98 1.68 164.5
(Developed) C Woods in Good Condition 70 1.12 78.4 79.3 2.61
Lawns in Good Condition(75%+Groundcover) 74 3.95 292.4
DA E Impervious Areas 98 0.12 12.1
(Developed) B Woods in Good Condition 55 0.56 30.8 61.9 6.17
Lawns in Good Condition(75%+Groundcover) 61 0.73 44.3
DA C mpervious Areas 98 0.10 9.8
C Woods in Good Condition 70 3.05 213.5 72.8 3.73
(Present)
Lawns in Good Condition(75%+Groundcover) 74 5.32 393.7
DA C Impervious Areas 98 0.61 59.6
(Developed) C Woods in Good Condition 70 0.24 16.8 82.8 2.08
Lawns in Good Condition(75%+Groundcover) 74 0.70 51.9
2.Runoff
1-Year Storm 2-Year Storm Drainage Area Description
Frequency-years 1 2 n/a
Rainfall,P(24 hour)-inches 3.5 3.7 n/a
Runoff,Q-inches 0.47 0.55 DA A(Present)
Runoff,Q-inches 1.24 1.38 DA B(Present)
Runoff,Q-inches 0.92; 1.04 DA A(Developed)
Runoff,Q-inches 1.78 1.95 DAB(Developed)
Runoff,Q-inches 0.64 0.74 DAD&E(Present)
Runoff,q-inches 1.59 1.75 DAD(Developed)
Runoff,Q-inches 0.61 0.70 DA E(Developed)
Runoff,Q-inches 1.17 1.31 DA C(Present)
Runoff,Q-inches 1.84 2.01 DA C(Developed)
U.S.Department of Agriculture FL-ENG-21A
Natural Resources Conservation Service 06/04
TR 55 Worksheet 3:Time of Concentration(To)or Travel Time(Ti)
Project: Wintergreen Farm Designed By:FGM,PE Date: 11/13/2015
Location: Sunset Ave/Redfield Rd/Wintergreen Ln.Boundary Checked By:SRC,PE Date: 11/13/2015
Check One: Present X Developed X
Check One: T, X T. Through subarea n/a
DAA DAB DAA DAB DAD&E DAD DAE DAC DAC
Segment ID: (Present) (Present) (Developed) (Developed) (Present) (Developed) (Developed) (Present) (Developed)
Sheet Flow:(Applicable to T,only)
Woods-Light Woods-Light Woods-Light Woods-Light Woods-Light Woods-Light Woods-Light
1 Surface description(Table 3-1) Underbrush Dense Grass Underbrush Underbrush Underbrush Underbrush Dense Grass Underbrush Underbrush
2 Manning's roughness coeff.,n(Table 3-1 0.4 0.24 0.4 0.4 0.4 0.4 0.24 0.4 0.4
3 Flow length,L(total I.<100)(ft) 100 100 100 100 100 100 100 100 100
4 Two-year 24-hour rainfall,Pa(in.) 3.7 3.7 3.7 3.7 3.7 3.7 3.7 3.7 3.7
5 Land slope,s(ft/ft) 0.06 0.13 0.06 0.06 0.05 0.05 0.14 0.06 0.09
6 Compute T.=[0.007(n•L)o.e)/Pzo.s s" I 0.21 I 0.10 I 0.21 I 0.21 I 0.23 I 0.23 I 0.102 I 0.21 I 0.18
Shallow Concentrated Flow:
7 Surface description(paved or unpaved) Unpaved Unpaved Unpaved Unpaved Unpaved Unpaved Unpaved Unpaved Unpaved
8 Flow Length,L(ft) 490 585 350 190 590 250 120 700 110
9 Watercourse slope,s(ft/ft) 0.078 0.115 0.077 0.074 0.090 0.064 0.317 0.066 0.164
10 Average velocity,V(Figure 3-1)(ft/s) 4.5 5.5 4.4 4.3 4.8 4.0 8.9 4.1 6.5
11 T.=L/3600"V I 0.03 I 0.03 I 0.02 I 0.01 I 0.03 I 0.02 I 0.004 I 0.05 I 0.00 I
Channel Flow:
12 Cross sectional flow area,a(ft=)
o r o o 3
13 Wetted perimeter,P.,(ft) -6LL > „ o
14 Hydraulic radius,r=a/Pw(ft) c AE ^5 °' T.
w N
15 Channel Slope,s(ft/ft) 1O 3 < 3 '�° °1 '^ A m
16 Manning's Roughness Coeff,n ' o '^ c' 'n ,...5
�+
5 0
17V=[1.49r s"s]/n a 6, ;n c P.: E `ov
18 Flow length,L(ft) 1O In N
19 Tt=L/3600•V I I I 0.01 I 0.04 I I m0.01 I I I 0.01 I
20 Watershed or subarea T,or T.
(Add Tt in steps 6,11 and 19) I 0.24 I 0.13 I 0.24 I 0.26 I 0.26 I 0.26 I 0.11 I 0.26 I 0.19
0
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Wintergreen Farm- Basin A- WITH AMENDED CN
BasinFlow printout
INPUT:
Basin: Wintergreen Farm- SWM Basin A- WITH AMENDED CN
5 Contour Areas
Elevation(ft) Area(sf) Computed Vol. (cy)
451.00 10938.00 0.0
452.00 13140.00 445.3
454.00 17855.00 1588.8
456.00 22892.00 3094.1
456.50 24215.00 3530.2
Start_Elevation(ft) 451.00 Vol. (cy) 0.00
4 Outlet Structures
Outlet structure 0
Orifice
name: Barrel
area (sf) 1.767
diameter or depth (in) 18.000
width for rect. (in) 0.000
coefficient 0.500
invert (ft) 446.320
multiple 1
discharge out of riser
Outlet structure 1
Orifice
name: Low Flow Orifice
area (sf) 0.349
diameter or depth (in) 8.000
width for rect. (in) 0.000
coefficient 0.500
invert (ft) 451.000
multiple 1
discharge into riser
Outlet structure 2
Weir
name: Riser Rim
diameter (in) 36.000
side angle 0.000
coefficient 3.300
invert (ft) 453.750
multiple 1
discharge into riser
transition at (ft) 0.912
orifice coef. 0.500
orifice area (sf) 7.069
Page 1
Wintergreen Farm- Basin A- WITH AMENDED CN
Outlet structure 3
Weir
name: Emergency Spillway
length (ft) 50.000
side angle 0.000
coefficient 3.300
invert (ft) 454.750
multiple 1
discharge through dam
3 Inflow Hydrographs
Hydrograph 0
SCS
name: 1-yr 24hr Peak SCS Design Storm
Area (acres) 22.800
CN 68.500
Type 2
rainfall, P (in) 3.500
time of conc. (hrs) 0.2400
time increment (hrs) 0.0200
time limit (hrs) 30.000
fudge factor 1.00
routed true
peak flow (cfs) 21.737
peak time (hrs) 12.002
volume (cy) 2839.493
Hydrograph 1
SCS
name: 2-yr 24hr Peak SCS Design Storm
Area (acres) 22.800
CN 68.500
Type 2
rainfall, P (in) 3.700
time of conc. (hrs) 0.2400
time increment (hrs) 0.0200
time limit (hrs) 30.000
fudge factor 1.00
routed true
peak flow (cfs) 24.554
peak time (hrs) 12.002
volume (cy) 3207.375
Page 2
Wintergreen Farm- Basin A- WITH AMENDED CN
Hydrograph 2
SCS
name: 100-yr 24hr Peak SCS Design Storm
Area (acres) 22.800
CN 68.500
Type 2
rainfall, P (in) 9.100
time of conc. (hrs) 0.2400
time increment (hrs) 0.0200
time limit (hrs) 30.000
fudge factor 1.00
routed true
peak flow (cfs) 122.736
peak time (hrs) 12.002
volume (cy) 16032.581
OUTPUT:
Routing Method: storage-indication
Hydrograph 0
Routing Summary of Peaks: 1-yr 24hr Peak SCS Design Storm
inflow (cfs) 21.728 at 12.00 (hrs)
discharge (cfs) 2.142 at 12.58 (hrs)
water level (ft) 453.675 at 12.62 (hrs)
storage (cy) 1378.664
Hydrograph 1
Routing Summary of Peaks: 2-yr 24hr Peak SCS Design Storm
inflow (cfs) 24.543 at 12.00 (hrs)
discharge (cfs) 3.680 at 12.42 (hrs)
water level (ft) 453.879 at 12.42 (hrs)
storage (cy) 1509.642
Hydrograph 2
Routing Summary of Peaks: 100-yr 24hr Peak SCS Design Storm
inflow (cfs) 122.684 at 12.00 (hrs)
discharge (cfs) 120.243 at 12.02 (hrs)
water level (ft) 455.465 at 12.02 (hrs)
storage (cy) 2654.304
Fri Jan 12137:%7:11 EST 2018
Page 3