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WPO201300050 Calculations 2013-07-10
Hydraflow Table of Contents TCSanholdWAHSrev2SCS.gpw Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Watershed Model Schematic 1 1 -Year Summary Report 2 Hydrograph Reports 3 Hydrograph No. 1, SCS Runoff, Drive Range PRE-SCS 3 Hydrograph No.2, SCS Runoff, Drive Range POST-SCS 4 TR-55 Tc Worksheet 5 Hydrograph No. 3, Reservoir, Pond 6 Pond Report- BioFilter Pond 7 10 -Year Summary Report 8 Hydrograph Reports 9 Hydrograph No. 1, SCS Runoff, Drive Range PRE-SCS 9 Hydrograph No. 2, SCS Runoff, Drive Range POST-SCS 10 Hydrograph No. 3, Reservoir, Pond 11 100 -Year Summary Report 12 Hydrograph Reports 13 Hydrograph No. 1, SCS Runoff, Drive Range PRE-SCS 13 Hydrograph No. 2, SCS Runoff, Drive Range POST-SCS 14 Hydrograph No. 3, Reservoir, Pond 15 1 Watershed Model Schematic Hydraflow Hydrographs by Inteksoive v9.2 '.. 1-Onve Range PRE-SCS 2..Clove Range POST-SCS 3..Pond • � r • ' — 3.. 1 i`- ` b 1' Project:TCSanholdWAHSrev2SCS.gpw Tuesday.Dec 17,2013 2 Hydrograph Summary Report Hydraflow Hydrographs by Intelisolve v9.2 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval peak volume hyd(s) elevation strge used description (origin) (cfs) (min) (min) (cult) (ft) (cuff) 1 SCS Runoff 0.420 1 718 1,538 ---- ---- ---- Drive Range PRE-SCS 2 SCS Runoff 7.123 1 715 12,854 ---- Drive Range POST-SCS 3 Reservoir 2.652 1 720 6,591 2 654.32 5,677 Pond TCSanholdWAHSrev2SCS.gpw Return Period:1 Year Tuesday,Dec 17,2013 3 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 1 Drive Range PRE-SCS Hydrograph type = SCS Runoff Peak discharge = 0.420 cfs Storm frequency = 1 yrs Time to peak = 11.97 hrs Time interval = 1 min Hyd. volume = 1,538 cuft Drainage area = 1.800 ac Curve number = 52 Basin Slope = 3.8% Hydraulic length = 400 ft Tc method = KIRPICH Time of conc. (Tc) = 2.78 min Total precip. = 3.50 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Drive Range PRE-SCS Q(cfs) Q(cfs) Hyd.No. 1 --1 Year 0.50 0.50 0.45 I 0.45 I 1 0.40 0.40 0.35 0.35 0.30 0.30 1 MIME 1 0.25 1 0.25 1 1 1 Mil 0.20 0.20 ME INIA 0.15 0.15 j I 0.10 MEI i 0.10 I I 0.05 " - 0.05 I I � 0.00 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 Hyd No.1 Time(hrs) ' 4 • Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 2 Drive Range POST-SCS Hydrograph type = SCS Runoff Peak discharge = 7.123 cfs Storm frequency = 1 yrs Time to peak = 11.92 hrs Time interval = 1 min Hyd. volume = 12,854 cuft Drainage area = 1.800 ac Curve number = 86* Basin Slope = 3.8% Hydraulic length = 400 ft Tc method = TR55 Time of conc. (Tc) = 2.70 min Total precip. = 3.50 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Composite(Area/CN)=[(0.450 x 48)+(1.350 x 98)]/1.800 Drive Range POST-SCS Q(cfs) Hyd.No.2—1 Year Q(cfs) 8.00 I I 8.00 I , II 6.00 A 6.00 4.00 I 4.00 I � 2.00 I 2.00 I ICI � I 0.00 - ' 0.00 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 Hyd No.2 Time(hrs) 5 TR55 Tc Worksheet Hydraflow Hydrographs by Intelisolve v9.2 Hyd. No. 2 Drive Range POST-SCS Description A B C Totals Sheet Flow Manning's n-value = 0.011 0.011 0.011 Flow length (ft) = 200.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.70 0.00 0.00 Land slope(%) = 3.75 0.00 0.00 Travel Time(min) = 1.53 + 0.00 + 0.00 = 1.53 Shallow Concentrated Flow Flow length(ft) = 200.00 0.00 0.00 Watercourse slope(%) = 2.00 0.00 0.00 Surface description = Paved Paved Paved Average velocity(ft/s) = 2.87 0.00 0.00 Travel Time(min) = 1.16 + 0.00 + 0.00 = 1.16 Channel Flow X sectional flow area(sqft) = 0.00 0.00 0.00 Wetted perimeter(ft) = 0.00 0.00 0.00 Channel slope(%) = 0.00 0.00 0.00 Manning's n-value = 0.015 0.015 0.015 Velocity(ft/s) = 0.00 0.00 0.00 Flow length (ft) = 0.0 0.0 0.0 Travel Time(min) = 0.00 + 0.00 + 0.00 = 0.00 Total Travel Time,Tc 2.70 min 6 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 3 Pond Hydrograph type = Reservoir Peak discharge = 2.652 cfs Storm frequency = 1 yrs Time to peak = 12.00 hrs Time interval = 1 min Hyd. volume = 6,591 cuft Inflow hyd. No. = 2- Drive Range POST-SCS Max. Elevation = 654.32 ft Reservoir name = BioFilter Pond Max. Storage = 5,677 cuft Storage Indication method used. Exflflration extracted from Outflow. Pond Q(cfs) Hyd.No.3—1 Year Q(cfs) 8.00 T I 8.00 i 6.00 6.00 4.00 4.00 2.00 2.00 0.00 — 0.00 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 Time(hrs) Hyd No.3 Hyd No.2 II I_IJ! Total storage used=5,677 cuft Pond Report ' Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Pond No. 1 - BioFilter Pond Pond Data Contours-User-defined contour areas.Conic method used for volume calculation.Begining Elevation=653.00 ft Stage/Storage Table Stage(ft) Elevation(ft) Contour area(sqft) Incr.Storage(cuft) Total storage(cuft) 0.00 653.00 3,278 0 0 1.00 654.00 4,488 3,867 3,867 2.00 655.00 6,845 5,625 9,491 3.00 656.00 8,160 7,492 16,984 4.00 657.00 9,515 8,828 25,812 Culvert/Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise(in) = 18.00 0.00 0.00 0.00 Crest Len(ft) = 5.00 10.00 0.00 0.00 Span(in) = 18.00 0.00 0.00 0.00 Crest El.(ft) = 654.00 655.60 0.00 0.00 No.Barrels = 1 0 0 0 Weir Coeff. = 3.33 2.60 3.33 3.33 Invert El.(ft) = 653.10 0.00 0.00 0.00 Weir Type = Broad Broad --- -- Length(ft) = 4.00 0.00 0.00 0.00 Multi-Stage = Yes No No No Slope(%) = 2.50 0.00 0.00 n/a N-Value = .012 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.500(by Contour) Multi-Stage = n/a No No No TW Elev.(ft) = 0.00 Note'.Culvert/Onfice outflows are analyzed under inlet(ic)and outlet(oc)control. Weir nsers checked for onf ice conditions(Ic)and submergence(s). Stage(ft) Stage/Discharge Elev(ft) 4.00 - --r-- 657.00 ' i I I i I 3.00 656.00 2.00 I I 655.00 I j i I I I I 1.00 j 654.00 I I II I i i i I I i I 0.00 I 653.00 0.00 6.00 12.00 18.00 24.00 30.00 36.00 42.00 48.00 54.00 60.00 Total Discharge(cfs) 8 Hydrograph Summary Report Hydraflow Hydrographs by Intelisolve v9.2 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval peak volume hyd(s) elevation strge used description (origin) (cfs) (min) (min) (cult) (ft) (cuff) 1 SCS Runoff 3.581 1 716 6,648 ---- ----- ----- Drive Range PRE-SCS 2 SCS Runoff 13.19 1 715 24,689 ---- ---- Drive Range POST-SCS 3 Reservoir 7.019 1 719 18,148 2 654.97 9,291 Pond TCSanholdWAHSrev2SCS.gpw Return Period:10 Year Tuesday,Dec 17,2013 9• Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 1 Drive Range PRE-SCS Hydrograph type = SCS Runoff Peak discharge = 3.581 cfs Storm frequency = 10 yrs Time to peak = 11.93 hrs Time interval = 1 min Hyd. volume = 6,648 cult Drainage area = 1.800 ac Curve number = 52 Basin Slope = 3.8% Hydraulic length = 400 ft Tc method = KIRPICH Time of conc. (Tc) = 2.78 min Total precip. = 5.60 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Drive Range PRE-SCS Q(cfs) Hyd.No.1 --10 Year Q(cfs) 4.00 i- 4.00 I i i I it j I I 3.00 3.00 2.00 2.00 1.00 i 1.00 I � j I II I i I i j i I i I I I i i 0.00J 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 Time(hrs) Hyd No.1 • 10 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 2 Drive Range POST-SCS Hydrograph type = SCS Runoff Peak discharge = 13.19 cfs Storm frequency = 10 yrs Time to peak = 11.92 hrs Time interval = 1 min Hyd. volume = 24,689 cuft Drainage area = 1.800 ac Curve number = 86* Basin Slope = 3.8% Hydraulic length = 400 ft Tc method = TR55 Time of conc. (Tc) = 2.70 min Total precip. = 5.60 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 •Composite(Area/CN)=[(0.450 x 48)+(1.350 x 98)]/1.800 Drive Range POST-SCS Q(cfs) Hyd.No.2-10 Year Q(cfs) 14.00 1 . 14.00 12.00 - 12.00 10.00 - 10.00 I I I I i I i 8.00 j 8.00 6.00 6.00 4.00 j - 4.00 2.00 { i 2.00 0.00 L 0.00 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 Hyd No.2 Time(hrs) 11 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 3 Pond Hydrograph type = Reservoir Peak discharge = 7.019 cfs Storm frequency = 10 yrs Time to peak = 11.98 hrs Time interval = 1 min Hyd. volume = 18,148 cuft Inflow hyd. No. = 2- Drive Range POST-SCS Max. Elevation = 654.97 ft Reservoir name = BioFilter Pond Max. Storage = 9,291 cuft Storage Indication method used. Exfiltration extracted from Outflow. Pond Q(cfs) Hyd.No.3-10 Year Q(cfs) 14.00 I 14.00 12.00 12.00 i 10.00 10.00 8.00 - 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 - J 0.00 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 22.0 Time(hrs) Hyd No.3 Hyd No.2 ILLL _Li Total storage used=9,291 cuft 1 1 12 Hydrograph Summary Report Hydraflow Hydrographs by Intelisolve v9.2 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval peak volume hyd(s) elevation strge used description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 SCS Runoff 11.24 1 716 19,553 ---- ---- Drive Range PRE-SCS 2 SCS Runoff 23.23 1 715 45,337 --- ---- Drive Range POST-SCS 3 Reservoir 11.33 1 719 38,314 2 655.63 14,164 Pond TCSanholdWAHSrev2SCS.gpw Return Period:100 Year Tuesday,Dec 17,2013 13 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 1 Drive Range PRE-SCS Hydrograph type = SCS Runoff Peak discharge = 11.24 cfs Storm frequency = 100 yrs Time to peak = 11.93 hrs Time interval = 1 min Hyd. volume = 19,553 cuft Drainage area = 1.800 ac Curve number = 52 Basin Slope = 3.8% Hydraulic length = 400 ft Tc method = KIRPICH Time of conc. (Tc) = 2.78 min Total precip. = 9.10 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Drive Range PRE-SCS Q(cfs) Q(cfs) Hyd.No.1 --100 Year 12.00 12.00 � I 10.00 j j f 10.00 i i j I I j I � 8.00 8.00 II I 6.00 I j 6.00 it I I I j I i j it j I j II 4.00 I — 4.00 2.00 li i i 2.00 I i 0.00 1` — l 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 Hyd No.1 Time(hrs) • 14 • Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 2 Drive Range POST-SCS Hydrograph type = SCS Runoff Peak discharge = 23.23 cfs Storm frequency = 100 yrs Time to peak = 11.92 hrs Time interval = 1 min Hyd. volume = 45,337 cuft Drainage area = 1.800 ac Curve number = 86* Basin Slope = 3.8% Hydraulic length = 400 ft Tc method = TR55 Time of conc. (Tc) = 2.70 min Total precip. = 9.10 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 •Composite(Area/CN)=[(0.450 x 48)+(1.350 x 98))/1.800 Drive Range POST-SCS Q(cfs) Hyd.No.2--100 Year Q(cfs) 24.00 I 24.00 20.00 j -- 20.00 I � 11 16.00 j ' } 1 16.00 I I I I l 12.00 j ! j 12.00 II I it � I i 8.00 - j 8.00 i I I I ' i I I li Iii � 4.00 j ' 4.00 I I 0.00 0.00 0.0 2.0 4.0 6.0 8.0 10.0 12.0 14.0 16.0 18.0 20.0 Time(hrs) Hyd No.2 15 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Tuesday,Dec 17,2013 Hyd. No. 3 Pond Hydrograph type = Reservoir Peak discharge = 11.33 cfs Storm frequency = 100 yrs Time to peak = 11.98 hrs Time interval = 1 min Hyd. volume = 38,314 cuft Inflow hyd. No. = 2- Drive Range POST-SCS Max. Elevation = 655.63 ft Reservoir name = BioFilter Pond Max. Storage = 14,164 cuft Storage Indication method used. Exfiltration extracted from Outflow. Pond Q(cfs) Hyd.No.3—100 Year Q(cfs) 24.00 24.00 20.00 20.00 16.00 16.00 12.00 12.00 8.00 8.00 4.00 4.00 0.00 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 Time(hrs) Hyd No.3 Hyd No.2 ® Total storage used=14,164 cuft M 2 M ni a E o o d e d c 9 C J 3 J - ' E O N o ; _ O N v o m S d co N W o E ui o o e mc 0 M C7 m a x m w CO J M M O i O 0. O6 > C r c 2 co - W o C O• c C 0c E m 2 m I I co a r o o e v d y N a it Itm N_ C � r O_ ch a 0.= Cl 1 C C 2 ci C V m = r 1 0 r re c 0 ) E o u F Li C O 5 E o 0 o X• ~ O d E Q o ✓ o .c O C C t o 0 .1■+ oc o 0 a CU 1 a 3 a V o II W F o n Q + 0 r O1 a U L c D c ° ° ° o I a d O = Q 2• c J W O a) o a V/ d a s 1 c• ~C W u c N W 4—, N C O I —a Z r. f m = E o R •a O m e c c J J E J m O co 3 o v N I W ' CO E d m o ❑ re co 1 co '- a x 7 v o m co W J CD• c• x o O o M II O 1 O wen- ® coo C W O Y y a E c• F E co O M Z co m 1 a a — n o e v m 7) N a 'a m N C co CI) Z.. m m v N U w -re , N I c 0 c _ lo C -• O • 0 ■ • c o w E o F m c o I e E o 0 K o 0 m e Q E o O C 0_ e y U o0 0 • J K o o it 9 u o n o II A Q ca E m C V• U c II L A O o U /�� O C W I O = Q r W J F m a• m O 0 '^ L o C ~C W L Y O —y U UJ LJJ ,∎• � C 0 O N CO _. - a z r) I i0 E a 2 0 N 0 C C m J E P. O m _1 C> 3 0 > a o 1 � 1 d m W E d E To e 0 e O q 0 C7 m z 0. ov v m CO W ■ J 0 0 O = M co m O > 0 u6 w N 2 (0 c W — `o t y g▪ c ° a m E o I m -- —Z m a - n O e v G N it m m N_ C V) O iii j m • G m 1 G_ N N 0 C C : c0 H .- c .q a t o r4 V e o ; C > E c f/1 o u H m C o c E o 9 0 0 x t- o pR G Q ` 0 .1 o c o C O c d U o 0 it Ix u o v o 0. 12 03 12 A o d il a E d ,CU ol C -• U /L G c :° o o• �u W O n cn _ Q CO co Q c G C �J Li., LL Y U i 0 N W N c o O 'w J d Z I WAHS BIORETENTION FILTER SIZING SUMMARY BASED ON VDCR DESIGN SPECIFICATION NO. 9 DEPTH STORAGE DESIGN SECTION FT. VOID RATIOS DEPTH SURFACE STORAGE 1.00 1.00 1.00 BIORETENTION SOIL 3.50 0.25 0.88 GRAVEL BELOW UNDERDRAINS 1.50 0.40 0.60 2.48 TREATMENT VOLUME (TV) FROM VDCR RRM WORKSHEET = 5,162 CU. FT. LEVEL 2 SURFACE AREA (SQ. FT.) = (TV X 1.25) / STORAGE DEPTH KEVEL SURFAXE AREA REOMED(SO.Fry ,=(5,,(5,,t62 i )12.48=2,802 `i ACE AREA '4 '. -6 25 Virginia Runoff Reduction Method Worksheet--Revised--03/25/2011 -Redevelopment Site Data Project Name:WAHS Phase-1 Bioretention Date: . ._.., ;„,_, data input cells calculation cells constant values Post-Development Project&Land Cover Information Constants Annual Rainfall(inches) Target Rainfall Event(inches) 1.00 Phosphorus EMC(mg/L) 0.26 Nit'.ten EMC m,/L 1.88 Target Phosphorus Target Load(Ib/acre/yr) 0.41 Pj 0.90 Pre-Development Land Cover (acres) A soils B Soils C Soils -ID Soils Totals ___1 Forest/Open Space(acres)-undisturbed, K ., -ti«_E � u :.� protected forest/open space or reforested land 1.80 0.00 0.00 0.00 1.80 Managed Turf(acres)--disturbed,graded for yards or other turf to be mowed/mana.ed !.,�r + .... , 0.00 _ Impervious Cover(acres) 0.00 Total 1.80 Post-Development 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 0.00 0.00 0.00 Managed Turf(acres)-disturbed,graded for yards or other turf to be mowed/managed 0, 6 ,,, Q,b,.. kit,' 0.36 Impervious Cover(acres) °"`"`'` " 1.44 Total 1.80 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 (p 0.95 0.95 ervious Cover _ _ 0.95 0.95 Land Cover Summary Land Cover Summary Pre-Development Post-Development Forest/Open Space Cover(acres) 74 ,, 1.80 Forest/Open Space Cover(acres) _ 0.00 Weighted Rv(forest) 0.02 Weighted Rv(forest) 0.00 %Forest 100% _ %Forest 0% Managed Turf Cover(acres) 0.00 Managed Turf Cover(acres) 0.36 Weighted Rv(turf) 0.00 Weighted Rv(turf) 0.15 %Managed Turf 0% %Managed Turf 20% Impervious Cover(acres) 0.00 Impervious Cover(acres) 1.44 ~ Rv(impervious) 0.95 Rv(impervious) 0 95 %Impervious 0% %Impervious 857 Total Site Area(acres) 1.80 Total Site Area(acres) 1.80 Site Rv 0.02 Site Rv 0.79, Pre-Development Treatment Volume(acre-ft) 0.0030 Post-Development Treatment Volume(acre-ft) 0.1185, Post-Development Treatment Volume(cubic Pre-Development Treatment Volume(cubic feet) 131 feet) 5,162 Pre-Development Load(TP)(Ib/yr) 0.08 Post-Development Load(TP)(lb/yr) 3.24 Maximum%Reduction Required Below Pre-Development Load I 20% Total Load(TP)Reduction Required(Ib/yr) I 2.51 Pre-Development Load(TN)(Ib/yr) 0.59 - - Post-Development Load(TN)(Ib/yr) I 23.20 VA DCR STORMWATER DESIGN SPECIFICATION NO.9 BIORETENTION Table 9.3. Bioretention Filter and Basin Design Criteria Level 1 Design(RR 40 TP:25) Level 2 Design(RR:80 TP: 50) Sizing (Section 6.1): Sizing (Section 6.1): Surface Area(sq. ft.)= (T„—the volume reduced Surface Area(sq. ft.)= [(1.25)(Tv)—the volume by an upstream BMP)/Storage Depth 1 reduced by an upstream BMP]/Storage Depth 1 Recommended maximum contributing drainage area=2.5 acres Maximum Pondinq Depth =6 to 12 inches 2 Maximum Pondinq Depth =6 to 12 inches 2 Filter Media Depth minimum=24 inches; Filter Media Depth minimum = 36 inches; recommended maximum =6 feet recommended maximum =6 feet Media&Surface Cover(Section 6.6)=supplied by vendor; tested for acceptable phosphorus index (P-Index)of between 10 and 30, OR Between 7 and 21 mg/kg of P in the soil media Sub-soil Testing (Section 6.2): not needed if an Sub-soil Testing (Section 6.2): one per 1,000 sq. underdrain used; Min infiltration rate > 1/2 ft. of filter surface; Min infiltration rate > 1/2 inch/hour in order to remove the underdrain inch/hour in order to remove the underdrain requirement. requirement. Underdrain & Underground Storage Layer Underdrain (Section 6.7) = Schedule 40 PVC with (Section 6.7) = Schedule 40 PVC with clean outs, clean-outs and a minimum 12-inch stone sump below the invert; OR, none, if soil infiltration requirements are met(Section 6.2) Inflow: sheetflow, curb cuts, trench drains, concentrated flow, or the equivalent Geometry (Section 6.3): Geometry (Section 6.3): Length of shortest flow path/Overall length = 0.3; Length of shortest flow path/Overall length = 0.8; OR, other design methods used to prevent short- OR, other design methods used to prevent short- circuiting; a one-cell design (not including the pre- circuiting; a two-cell design (not including the treatment cell). pretreatment cell). Pre-treatment (Section 6.4): a pretreatment cell, Pre-treatment (Section 6.4): a pretreatment cell grass filter strip, gravel diaphragm, gravel flow plus one of the following: a grass filter strip, gravel spreader, or another approved (manufactured) diaphragm, gravel flow spreader, or another pre-treatment structure. approved (manufactured) pre-treatment structure. Conve ance&Overflow Section 6.5 Conve ance&Overflow Section 6.5 Planting Plan (Section 6.8): a planting template to Planting Plan (Section 6.8): a planting template to include turf, herbaceous vegetation, shrubs, include turf, herbaceous vegetation, shrubs, and/or trees to achieve surface area coverage of and/or trees to achieve surface area coverage of at least 90% within 2 years. If using turf, must at least 75%within 2 years. combine with other types of vegetation . Building Setbacks 3(Section 5): 0 to 0.5 acre CDA= 10 feet if down-gradient from building or level (coastal plain); 50 feet if up-gradient. 0.5 to 2.5 acre CDA= 25 feet if down-gradient from building or level (coastal plain); 100 feet if up- gradient. (Refer to additional setback criteria in Section 5) Deeded Maintenance O&M Plan (Section 8) Storage depth is the sum of the Void Ratio(Vr)of the soil media and gravel layers multiplied by their respective depths, plus the surface ponding depth. Refer to Section 6.1. 2 A ponding depth of 6 inches is preferred. Ponding depths greater than 6 inches will require a specific planting plan to ensure appropriate plant selection (Section 6.8). 3 These are recommendations for simple building foundations. If an in-ground basement or other special conditions exist,the design should be reviewed by a licensed engineer. Also, a special footing or drainage design may be used to justify a reduction of the setbacks noted above. Version 1.9, March 1, 2011 Page 5 of 54 rn \ " q § 8 \?k \ w a a \ \ \ rn n1 z E 0 0 0 Cl)2 E 0 0 >> q §r r r Cl) 2 mm ? > • -1 r 0& _ 0\ \ § o = p X12 01 � s $ cn m mm m 3 ¥ ¥ a ■ _ - _. •m r 0 on 00 � � 0 z @ 0 2 \ / fs ° co -4 > \ $ 2 m m 73 ) \ k 0) . co g m = e o 0 rl o Z 2 @ = « c _ � Cn -< > / \ \ CO r or.. y / m w - z n 0 n 0 0 -4 CD Cn D Z / / r m % $ @ z R§ r mz ° d >cE % $ D 0H \ CO\ z \ < z r- § g I / \ \ kjk 0 -n x § §2 cn cf 0 cn \ \ Cl) n m « z Cl) > x = m z z m k x \ r m -0 - - ƒ ■ @ 0) Z 6 o o = z -n ® TCSEnc,ineerinci Com LLC Outlet Channel Design: WAHS Bio-Detention Pond 2013 Date: 25JUN2013 By: J. Taggart, P.E. A biodetention basin has been designed by Anhold&Associates and TCS Engineering for the school facility near the driving range in the southern portion of the Crozet Campus of Western Albemarle High School. As a major component of the pond design,a storm manhole serves dual duty as a conveyance structure carrying runoff water to the pond as well as a riser structure(via an internal weir) allowing water to leave the pond during highwater events. As such,a piped discharge(24"ADS pipe)leaves this manhole and discharges to a manmade open conveyance channel. Since this pond structure is designed to fully contain the 10 year event,there is no normal design flow for this conveyance channel. Because of the sensitive nature of the downstream receiving channel,a cautious approach and overdesign of the conveyance channel has been taken: An assumption will be made that the pond is inoperable and the entire post developed flow will be directed toward the 24"piped discharge. This will direct some 11.5 CFS to the conveyance channel. The following pages describe the required channel section and amoring(outlet protection)for the conveyance channel. Conclusion&Recommendation: At the end of the 24"outlet pipe,contractor shall install a trapezoidal channel:with bottom width of 24 inches, 12 inches deep with 2:1 side walls. There shall be a minimum armoring of 8 inch(d50)Rip-rap,to an average depth of 16 inches for a minimum length of 15 ft. from the end of the pipe(or the natural slope reduces to<5%,whichever distance is greater). The width of the rip rap section shall be the full width of the channel section. TH Opp 4,1..—December 12,2012 x o JIMMY L TAGGART(CERTIFICATE) No. °D` 22841 rI `� IOIVAL 741 Duncan Hollow Loop Faber,VA 22938 Ph.434/361-1215 Email: JTagg2 @AOL.com Hydrology Report Hydraflow Express by Intelisolve Tuesday,Jun 25 2013 WAHS Project post runoff- 10 yr. Event Hydrograph type = Rational Peak discharge (cfs) = 11.50 Storm frequency(yrs) = 10 Time interval (min) = 1 Drainage area (ac) = 1.800 Runoff coeff. (C) = 0.9 Rainfall Inten (in/hr) = 7.096 Tc by FAA(min) = 5 IDF Curve = Albmrle.IDF Rec limb factor = 1.50 Hydrograph Volume=4,311 (cult);0.099(acft) Runoff Hydrograph Q(cfs) 10-yr frequency Q(cfs) 12.00 12.00 10.00 10.00 8.00 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 - 0.00 0 5 10 15 Time(min) Runoff Hyd-Qp= 11.50(cfs) FAA Formula Tc Worksheet Tc=1.8(1.1-C)x Flow length"0.5/Watercourse slope"0.333 Hydraflow Express by Intelisolve Rational WAHS Project post runoff- 10 yr. Event Description Flow length (ft) = 400.00 Watercourse slope (%) = 3.75 Runoff coefficient (C) = 0.90 Time of Conc. (min) = 5 Channel Report HydraAow Express by Intelisolve Tuesday,Jun 25 2013 WAHS Pond Discharge Channel- 10 yr. (Assume Pond is inoperable) Trapezoidal Highlighted Botom Width (ft) = 2.00 Depth (ft) = 0.39 Side Slopes (z:1) = 2.00, 2.00 Q (cfs) = 11.50 Total Depth (ft) = 1.00 Area (sqft) = 1.08 Invert Elev(ft) = 633.80 Velocity(ft/s) = 10.61 Slope (%) = 43.00 Wetted Perim (ft) = 3.74 N-Value = 0.040 Crit Depth, Yc (ft) = 0.78 Top Width (ft) = 3.56 Calculations EGL(ft) = 2.14 Compute by: Known Q Known Q (cfs) = 11.50 Elev (ft) Depth Section ft p { ) 635.00 1.20 env 634.50 i 0.70 634.00 0.20 633.50 -0.30 633.00 -0.80 0 1 2 3 4 5 6 7 8 Reach (ft) 1992 3.18 R 0 N quatleV7 t-N) -tt.) (1.153 - 1 4aas 'az1S aPAPe °SP V) CI.. ,.., C>;1", 2 1 . I ..... , 7_ . c,,,, 1 4 " '41111111.111'.,,,,,,71111;:41161" ' ' ' a-4-- --- „.., 1 1 , , -,,,-„,-;:,., --,-,‘„,, ..„. 4, i 1 Q 6 _ 0 1 # t -,. '114,,... 4.7\4 I - :'`, .. .... 7 z,„ . \ 1 .- ,...,:\..s.,. ,...\ „ ',..„ i' 4 .... . I 4;;;;>4 IN ■ ; \ \■;..,.1,,,,4, 114 ,\„. SI., \ , ...9. S \ on C'1 r: \ \ , , I ' I r. , .. . t tt, '.. ' ..., -.0 t , 1 CI I ...".” 1 1 ft \\ ...5..., i..v i .„I■••-■ re, ) ,. ....or %.....,1 .02... ^ / / \ .0.° a, , ^.. 0. -0 "' ,,---,- . r.,,,., it ._,,.. . : ,' 1.' — ^..f ,r. t / , ^ i. ' .,-7-------T-------- t. - i cs ;. ,-... , .,- 'c 1, • : :-. c.> .1.7...r.L. ...., — • ......1,1.1 ; . I ,-.-, a , , c,.-■ " , ■--1 1 .115 a C -,-,,, ¢, a, ,■ •-." +-,,... Z ..,1 ..... ...... 0 -3 X. 4... II t z ....3z 6" Source: USDA-SCS Plate 3.18-3 111 - )64 DA-3 DA-2 1 \:#1 1 SCC-3 SCC-2 1 1 Subcat Reach -on. Drainage Diagram for WAHS Watershed 4 Channel Prepared by ANHOLD ASSOCIATES, Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC WAHS Watershed 4 Channel Type 1124-hr 2-Year Rainfall=4.00" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 2 Summary for Subcatchment DA-2: 1 Runoff = 1.89 cfs @ 12.07 hrs, Volume= 0.182 af, Depth= 0.81" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.10-25.10 hrs, dt= 0.25 hrs Type II 24-hr 2-Year Rainfall=4.00" Area (ac) CN Description 0.660 98 Roofs, HSG A 0.150 98 Paved parking, HSG A * 0.310 75 Gravel & Dirt 0.420 49 50-75% Grass cover, Fair, HSG A 1.150 36 Woods, Fair, HSG A 2.690 61 Weighted Average 1.880 69.89% Pervious Area 0.810 30.11% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.6 85 0.0500 0.31 Sheet Flow, LAWN Grass: Short n= 0.150 P2= 5.40" 0.2 15 0.0400 1.61 Sheet Flow, PVMT Smooth surfaces n= 0.011 P2= 5.40" 0.2 48 0.1200 5.20 Shallow Concentrated Flow, Grass - Mowed Grassed Waterway Kv= 15.0 fps 2.1 300 0.9000 2.37 Shallow Concentrated Flow, Woodland Flow Forest w/Heavy Litter Kv= 2.5 fps 7.1 448 Total WAHS Watershed 4 Channel Type 1124-hr 2-Year Rainfall=4.00" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 3 Subcatchment DA-2: 1 Hydrograph / 0 Runoff 2� 11.89cfs 1 4 Type II 24-hr 2-Year Rainfall=4.00" Runoff Area=2.690 ac ''z . Runoff Volume=0.182 of Runoff Depth=0.81" rol. Flow Length=448' 6 Tc=7.1 min CN=61 A,.016V:eepeleZirse:440:04:07:" 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hours) WAHS Watershed 4 Channel Type 1124-hr 2-Year Rainfall=4.00" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 6 Summary for Reach SCC-2: 1 Inflow Area = 2.690 ac, 30.11% Impervious, Inflow Depth = 0.81" for 2-Year event Inflow = 1.89 cfs @ 12.07 hrs, Volume= 0.182 of Outflow = 1.89 cfs @ 12.07 hrs, Volume= 0.182 at Atten= 0%, Lag= 0.2 min Routing by Stor-Ind+Trans method, Time Span= 0.10-25.10 hrs, dt= 0.25 hrs Max. Velocity= 5.61 fps, Min. Travel Time= 0.1 min Avg. Velocity = 2.05 fps, Avg. Travel Time= 0.3 min Peak Storage= 14 cf @ 12.07 hrs Average Depth at Peak Storage= 0.15' Bank-Full Depth= 1.00', Capacity at Bank-Full= 64.55 cfs 2.00' x 1.00' deep channel, n= 0.025 Stream, clean &straight Side Slope Z-value= 2.0 '/' Top Width= 6.00' Length=40.0' Slope= 0.1400 'P Inlet Invert= 646.50', Outlet Invert= 640.90' Reach SCC-2: 1 Hydrograph ®Inflow rinds'. ®Outflow 2- 11.89 cfs Inflow Area=2.690 ac a; i' Avg. Flow Depth=0.15' ,t Max Vel=5.61 fps n=0.025 ,, L=40.0' LL 1J S=0.1400 '/' it Capacity=64.55 cfs sat 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) WAHS Watershed 4 Channel Type 1124-hr 10-Year Rainfall=5.60" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 8 Summary for Subcatchment DA-2: 1 Runoff = 4.32 cfs @ 12.03 hrs, Volume= 0.391 af, Depth= 1.74" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.10-25.10 hrs, dt= 0.25 hrs Type II 24-hr 10-Year Rainfall=5.60" Area (ac) CN Description 0.660 98 Roofs, HSG A 0.150 98 Paved parking, HSG A * 0.310 75 Gravel & Dirt 0.420 49 50-75% Grass cover, Fair, HSG A 1.150 36 Woods, Fair, HSG A 2.690 61 Weighted Average 1.880 69.89% Pervious Area 0.810 30.11% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 4.6 85 0.0500 0.31 Sheet Flow, LAWN Grass: Short n= 0.150 P2= 5.40" 0.2 15 0.0400 1.61 Sheet Flow, PVMT Smooth surfaces n= 0.011 P2= 5.40" 0.2 48 0.1200 5.20 Shallow Concentrated Flow, Grass - Mowed Grassed Waterway Kv= 15.0 fps 2.1 300 0.9000 2.37 Shallow Concentrated Flow, Woodland Flow Forest w/Heavy Litter Kv= 2.5 fps 7.1 448 Total WAHS Watershed 4 Channel Type 1124-hr 10-Year Rainfall=5.60" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 9 Subcatchment DA-2: 1 Hydrograph 0 Runoff 1 4.32 cfs I Type II 24-hr 10-Year 4 Rainfall=5.60" Runoff Area=2.690 ac 3- Runoff Volume=0.391 of Runoff Depth=1.74 u. 2- Flow Length=448' Tc=7.1 min CN=61 o 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hours) WAHS Watershed 4 Channel Type 1124-hr 10-Year Rainfall=5.60" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 12 Summary for Reach SCC-2: 1 Inflow Area = 2.690 ac, 30.11% Impervious, Inflow Depth = 1.74" for 10-Year event Inflow = 4.32 cfs @ 12.03 hrs, Volume= 0.391 af Outflow = 4.32 cfs @ 12.03 hrs, Volume= 0.391 af, Atten= 0%, Lag= 0.2 min Routing by Stor-Ind+Trans method, Time Span= 0.10-25.10 hrs, dt= 0.25 hrs Max. Velocity= 7.31 fps, Min. Travel Time= 0.1 min Avg. Velocity = 2.59 fps, Avg. Travel Time= 0.3 min Peak Storage= 24 cf @ 12.03 hrs Average Depth at Peak Storage= 0.24' Bank-Full Depth= 1.00', Capacity at Bank-Full= 64.55 cfs 2.00' x 1.00' deep channel, n= 0.025 Stream, clean & straight Side Slope Z-value= 2.0 'I' Top Width= 6.00' Length= 40.0' Slope= 0.1400 '/' Inlet Invert= 646.50', Outlet Invert= 640.90' Reach SCC-2: 1 Hydrograph / ®Inflow 1 4.32 cfs I ®Outflow 4.32 cfs Inflow Area=2.690 ac Avg. Flow Depth=0.24' Max VeI=7.31 fps n=0.025 L=40.0' S=0.1400 '/' 2_ Capacity=64.55 cfs 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) 1992 3.18 • laaj `azLs deudin 05p V , CV 0 0 .�a a.-- k 06 - _ I S11141 . .. 8! p `: moo �,o N - p 09 - . ._ "' �aA c> �. Vii ► '5':111114. ' : '41111_ ' NI • CD O .- 90 r t"L :.6 ia6 cv -.. J d -_ - —a.-.. .-_ _._ - u o 0 j --_ '.SL", , � w w .Y O N a F- O n r Z w a �, j- _1 UA 1 4 Q 6 -- ---__.. O O cz,C v 3_.y,I N __� __�__�–___�___ ._._ -.._ Z Z i 13 V ._ W J Q =O 4---4 - O O O Q S.- N 1.4- I- Y Y O E CU CD N C 7 O Y d A LO CI. £ o V) TJ O f CI, O 4 N O- V ii N CC Source: USDA-SCS Plate 3.18-3 III - 164 WAHS Watershed 4 Channel Type 1124-hr 2-Year Rainfall=4.00" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 4 Summary for Subcatchment DA-3: 1 Runoff = 7.06 cfs @ 12.02 hrs, Volume= 0.670 af, Depth= 1.09" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.10-25.10 hrs, dt= 0.25 hrs Type II 24-hr 2-Year Rainfall=4.00" Area (ac) CN Description 0.853 98 Roofs, HSG A 1.415 98 Paved parking, HSG A * 0.440 75 Gravel & Dirt 4.692 49 50-75% Grass cover, Fair, HSG A 7.400 66 Weighted Average 5.132 69.35% Pervious Area 2.268 30.65% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 1.4 28 0.1000 0.33 Sheet Flow, LAWN Grass: Short n= 0.150 P2= 5.40" 0.8 110 0.0400 2.40 Sheet Flow, PVMT Smooth surfaces n= 0.011 P2= 5.40" 0.5 150 0.1200 5.20 Shallow Concentrated Flow, Grass - Mowed Grassed Waterway Kv= 15.0 fps 1.2 160 0.1000 2.21 Shallow Concentrated Flow, Grass Meadow Short Grass Pasture Kv= 7.0 fps 2.6 300 0.6000 1.94 Shallow Concentrated Flow, Woodland Flow Forest w/Heavy Litter Kv= 2.5 fps 6.5 748 Total WAHS Watershed 4 Channel Type 1124-hr 2-Year Rainfall=4.00" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 5 Subcatchment DA-3: 1 Hydrograph 0 Runoff 1 706cfs f f Type II 24-hr 2-Year k Rainfall=4.00" Runoff Area=7.400 ac 5- . Runoff Vol ume=0.670 af il 4 ; . Runoff Depth=1.09" LL =Flow Length=748' 3" Tc=6.5 min 2 CN=66 ,_ 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hours) WAHS Watershed 4 Channel Type 1124-hr 2-Year Rainfall=4.00" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 7 Summary for Reach SCC-3: 1 Inflow Area = 7.400 ac, 30.65% Impervious, Inflow Depth = 1.09" for 2-Year event Inflow = 7.06 cfs @ 12.02 hrs, Volume= 0.670 af Outflow = 7.07 cfs @ 12.03 hrs, Volume= 0.670 af, Atten= 0%, Lag= 0.3 min Routing by Stor-Ind+Trans method, Time Span= 0.10-25.10 hrs, dt= 0.25 hrs Max. Velocity= 8.89 fps, Min. Travel Time= 0.1 min Avg. Velocity = 3.23 fps, Avg. Travel Time= 0.3 min Peak Storage= 48 cf @ 12.02 hrs Average Depth at Peak Storage= 0.23' Bank-Full Depth= 2.00', Capacity at Bank-Full=415.09 cfs 3.00' x 2.00' deep channel, n= 0.025 Stream, clean & straight Side Slope Z-value= 2.0 '/' Top Width= 11.00' Length= 60.0' Slope= 0.2013 '/' Inlet Invert= 645.00', Outlet Invert= 632.92' ��ta'-+6u +an9^v'.Bdonir+4+awfix Reach SCC-3: 1 Hydrograph / ■Inflow 17 06 cfs I 0 Outflow 1707cfs Inflow Area=7.400 ac Avg. Flow Depth=0.23' 6-' Max Vel=8.89 fps 5- n=0.025 4 L=60.0' -' LL S=0.2013 '/' Capacity=-415.09 cfs 2- 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) WAHS Watershed 4 Channel Type 1124-hr 10-Year Rainfall=5.60" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 10 Summary for Subcatchment DA-3: 1 Runoff = 14.79 cfs @ 11.97 hrs, Volume= 1.325 af, Depth= 2.15" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.10-25.10 hrs, dt= 0.25 hrs Type II 24-hr 10-Year Rainfall=5.60" Area (ac) CN Description 0.853 98 Roofs, HSG A 1.415 98 Paved parking, HSG A * 0.440 75 Gravel & Dirt 4.692 49 50-75% Grass cover, Fair, HSG A 7.400 66 Weighted Average 5.132 69.35% Pervious Area 2.268 30.65% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) fft/ft) (ft/sec) (cfs) 1.4 28 0.1000 0.33 Sheet Flow, LAWN Grass: Short n= 0.150 P2= 5.40" 0.8 110 0.0400 2.40 Sheet Flow, PVMT Smooth surfaces n= 0.011 P2= 5.40" 0.5 150 0.1200 5.20 Shallow Concentrated Flow, Grass - Mowed Grassed Waterway Kv= 15.0 fps 1.2 160 0.1000 2.21 Shallow Concentrated Flow, Grass Meadow Short Grass Pasture Kv= 7.0 fps 2.6 300 0.6000 1.94 Shallow Concentrated Flow, Woodland Flow Forest w/Heavy Litter Kv= 2.5 fps 6.5 748 Total WAHS Watershed 4 Channel Type 1124-hr 10-Year Rainfall=5.60" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 11 Subcatchment DA-3: 1 Hydrograph 16 0 Runoff 15—:- 1 1479,7 14 Type II 24-hr 10-Year 13_ ,1 Rainfall=5.60" r Runoff Area=7.400 ac 1 112-- r ; Runoff Volume=1.325 of Y Runoff Depth-=2.:15 o 8_ Flow Length=748' LL 7, r" 6- r Tc=6.5 min 5=' a"a 4� i��. CN=66 t, 3t-- 6 2--E, 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Time (hours) WAHS Watershed 4 Channel Type 1124-hr 10-Year Rainfall=5.60" Prepared by ANHOLD ASSOCIATES Printed 8/12/2013 HydroCAD®9.10 s/n 06201 ©2009 HydroCAD Software Solutions LLC Page 13 Summary for Reach SCC-3: 1 Inflow Area = 7.400 ac, 30.65% Impervious, Inflow Depth = 2.15" for 10-Year event Inflow = 14.79 cfs @ 11.97 hrs, Volume= 1.325 of Outflow = 14.55 cfs @ 11.98 hrs, Volume= 1.325 af, Atten= 2%, Lag=0.4 min Routing by Stor-Ind+Trans method, Time Span= 0.10-25.10 hrs, dt= 0.25 hrs Max. Velocity= 11.13 fps, Min. Travel Time= 0.1 min Avg. Velocity = 3.85 fps, Avg. Travel Time= 0.3 min Peak Storage= 77 cf @ 11.98 hrs Average Depth at Peak Storage= 0.35' Bank-Full Depth= 2.00', Capacity at Bank-Full=415.09 cfs 3.00' x 2.00' deep channel, n= 0.025 Stream, clean & straight Side Slope Z-value= 2.0 '1 Top Width= 11.00' Length= 60.0' Slope= 0.2013 '/' Inlet Invert= 645.00', Outlet Invert= 632.92' Reach SCC-3: 1 Hydrograph 0 Inflow 16 1 14.79 ers 1 0 Outflow 157 11455th Inflow Area-- 7.400 ac Ott 14= Avg..Flow Depth=-.0.35' 12; Max Vet=11.13 fps ,o= Alff n=0.025 L=60.0' 3 8_ o S=0.2013 '/' Litt Capacity--415.09 cfs 5� 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) 1992 3.18 laaj. `aziS de.adid 0Cp V M N V 00 o•s !�:. a i '.N' : ..;�, • \ :- f _� g6, .S:1144.1& 8,,, - . ..CMS o . a , ee : �. i -__- a-7 0: -' - p - -- 1 _ 4-Nk, . . - .6S { i � q 86 9^ ill: A o c 6 --- -- - ------ - ----ice' 0 0 A A 0 }} 1s A �` a __ —f a s _ d�.,1411- 06, \1- EIMIE m -- - ‘‘1L 1 "q i a U C7 O O - i ,ai i _- ' ^ 6 f - ; w s LLJ W ..le o J M w 1 _ e'' N e� OL CL. .' Y es —s --, ow D z o 0 0 O Q p (G` O " V II v G v - i =t ai : ,„AMIN o o a z '6 �s �.,� G ...�w�_ 1- 0 -J 3 M O ==..WREAM M O.-. - O O O t Q L N W H 4 I!! C Ls M Z O d O O E N C N E- O 8 , V II N 0. w Source: USDA-SCS Plate 3.18-3 III - 164 f Hydraflow Table of Contents TCSanholdWAHSoptb.gpw • Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Watershed Model Schematic 1 1 - Year Summary Report 2 Hydrograph Reports 3 Hydrograph No. 1, Rational, Drive Range PRE 3 FAA Tc Worksheet 4 Hydrograph No. 2, Rational, Drive Range POST 5 FAA Tc Worksheet 6 Hydrograph No. 3, Reservoir, BioFilter Pond 7 Pond Report- BioFilter Pond 8 2 - Year Summary Report 9 Hydrograph Reports 10 Hydrograph No. 1, Rational, Drive Range PRE 10 Hydrograph No. 2, Rational, Drive Range POST 11 Hydrograph No. 3, Reservoir, BioFilter Pond 12 10 - Year Summary Report 13 Hydrograph Reports 14 Hydrograph No. 1, Rational, Drive Range PRE 14 Hydrograph No. 2, Rational, Drive Range POST 15 Hydrograph No. 3, Reservoir, BioFilter Pond 16 100 - Year Summary Report 17 Hydrograph Reports 18 Hydrograph No. 1, Rational, Drive Range PRE 18 Hydrograph No. 2, Rational, Drive Range POST 19 Hydrograph No. 3, Reservoir, BioFilter Pond 20 • Watershed Model Schematic Hydraflow Hydrographs by Intelisolve v9.2 1 -Drive Range PRE 2-Drive Range POST 0 3-BioFilter Pond Project:TCSanholdWAHSoptb.gpw Monday, Jun 24, 2013 2 Hydrograph Summary Report Hydraflow Hydrographs by Intelisolve v9.2 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval peak volume hyd(s) elevation strge used description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 1.247 1 20 1,998 ---- Drive Range PRE 2 Rational 7.772 1 5 3,113 ---- Drive Range POST 3 Reservoir 1.853 1 11 2,821 2 653.61 2,374 BioFilter Pond TCSanholdWAHSoptb.gpw Return Period: 1 Year Monday, Jun 24, 2013 Hydrograph Report 3 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 1 Drive Range PRE Hydrograph type = Rational Peak discharge = 1.247 cfs Storm frequency = 1 yrs Time to peak = 20 min Time interval = 1 min Hyd. volume = 1,998 cuft Drainage area = 1.800 ac Runoff coeff. = 0.25 Intensity = 2.771 in/hr Tc by FAA = 20.00 min IDF Curve = Albmrle.IDF Asc/Rec limb fact = 1/1.67 Drive Range PRE Q (cfs) Q (cfs Hyd. No. 1 -- 1 Year ) 2.00 - - 2.00 1.00 1.00 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 0.00 Hyd No. 1 Time(min) FAA Formula Tc Worksheet 4 Tc=1.8(1.1 -C)x Flow length^0.5/Watercourse slope^0.333 Hydraflow Hydrographs by Intelisolve v9.2 Hyd. No. 1 Drive Range PRE Description Flow length (ft) = 400.00 Watercourse slope (%) = 3.75 Runoff coefficient (C) = 0.25 Time of Conc. (min) = 20 Hydrograph Report 5 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 2 Drive Range POST Hydrograph type = Rational Peak discharge = 7.772 cfs Storm frequency = 1 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 3,113 cuft Drainage area = 1.800 ac Runoff coeff. = 0.9 Intensity = 4.798 in/hr Tc by FAA = 5.00 min IDF Curve = Albmrle.IDF Asc/Rec limb fact = 1/1.67 Drive Range POST Q (cfs) Q (cfs Hyd. No. 2-- 1 Year ) 8.00 8.00 1N\ 6.00 /,//4111 ' 6.00 4.00 4.00 2.00 2.00 0.00 -- 0 1 2 3 4 5 6 7 8 9 10 11 12 13 0.00 Time(min) - Hyd No. 2 FAA Formula Tc Worksheet 6 Tc=1.8(1.1 -C)x Flow length^0.5/Watercourse slope^0.333 Hydraflow Hydrographs by Intelisolve v9.2 Hyd. No. 2 Drive Range POST Description Flow length (ft) = 400.00 Watercourse slope (%) = 3.75 Runoff coefficient (C) = 0.90 Time of Conc. (min) = 5 7 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 3 BioFilter Pond Hydrograph type = Reservoir Peak discharge = 1 .853 cfs Storm frequency = 1 yrs Time to peak = 11 min Time interval = 1 min Hyd. volume = 2,821 cuft Inflow hyd. No. = 2 - Drive Range POST Max. Elevation = 653.61 ft Reservoir name = BioFilter Pond Max. Storage = 2,374 cuft Storage Indication method used. Exfiltration extracted from Outflow. BioFilter Pond Q (cfs) (cfs) Hyd. No. 3 -- 1 Year ( ) 8.00 8.00 6.00 6.00 4.00 • 4.00 2.00 2.00 0.00 0.00 0 20 40 60 80 100 120 140 160 180 200 220 Time (min) Hyd No. 3 Hyd No. 2 air] I Total storage used = 2,374 cuft Pond Report 8 • Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Pond No. 1 - BioFilter Pond Pond Data Contours-User-defined contour areas.Conic method used for volume calculation.Begining Elevation=653.00 ft Stage/Storage Table Stage(ft) Elevation(ft) Contour area(sqft) Incr.Storage(cuft) Total storage(cuft) 0.00 653.00 3,278 0 0 1.00 654.00 4,488 3,867 3,867 2.00 655.00 7,276 5,826 9,692 2.60 655.60 8,257 4,656 14,349 Culvert/Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise(in) = 24.00 18.00 0.00 0.00 Crest Len(ft) = 5.00 10.00 0.00 0.00 Span(in) = 24.00 18.00 0.00 0.00 Crest El.(ft) = 653.80 654.50 0.00 0.00 No.Barrels = 1 1 0 0 Weir Coeff. = 2.60 2.60 3.33 3.33 Invert El.(ft) = 648.00 653.00 0.00 0.00 Weir Type = Broad Broad Length(ft) = 78.00 7.20 0.00 0.00 Multi-Stage = Yes No No No Slope(%) = 18.21 0.00 0.00 n/a N-Value = .012 .012 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 1.000(by Contour) Multi-Stage = n/a Yes No No TW Elev.(ft) = 0.00 Note:Culvert/Orifice outflows are analyzed under inlet(ic)and outlet(oc)control. Weir risers checked for orifice conditions(ic)and submergence(s). Stage(ft) Stage/Discharge 3.00 Elev(ft) 656.00 2.00 - 655.00 1.00 654.00 0.00 0.00 7.00 14.00 21.00 28.00 35.00 42.00 49.00 56.00 63.00 70.00653.00 Total Q Discharge(cfs) 9 Hydrograph Summary Report Hydraflow Hydrographs by Intelisolve v9.2 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval peak volume hyd(s) elevation strge used description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 1.366 1 20 2,188 ---- Drive Range PRE 2 Rational 8.413 1 5 3,369 ---- Drive Range POST 3 Reservoir 2.084 1 11 3,064 2 653.66 2,540 BioFilter Pond TCSanholdWAHSoptb.gpw Return Period: 2 Year Monday, Jun 24, 2013 Hydrograph Report 10 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 1 Drive Range PRE Hydrograph type = Rational Peak discharge = 1.366 cfs Storm frequency = 2 yrs Time to peak = 20 min Time interval = 1 min Hyd. volume = 2,188 cuft Drainage area = 1.800 ac Runoff coeff. = 0.25 Intensity = 3.035 in/hr Tc by FAA IDF Curve = Albmrle.IDF y = 20.00 min Asc/Rec limb fact = 1/1.67 Q (cfs) Drive Range PRE Hyd. No. 1 --2 Year Q (cfs) 2.00 2.00 1.00 1.00 0.00 — 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 0.00 • Hyd No. 1 Time (min) • Hydrograph Report 11 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 2 Drive Range POST Hydrograph type = Rational Peak discharge = 8.413 cfs Storm frequency = 2 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 3,369 cuft Drainage area = 1.800 ac Runoff coeff. = 0.9 Intensity = 5.193 in/hr Tc by FAA IDF Curve = Albmrle.IDF y = 5.00 min Asc/Rec limb fact = 1/1.67 Q (cfs) Drive Range POST Hyd. No. 2--2 Year Q (cfs) 10.00 10.00 8.00 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 0 0.00 1 2 3 4 5 6 7 8 9 10 11 12 13 Hyd No. 2 Time(min) 12 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 3 BioFilter Pond Hydrograph type = Reservoir Peak discharge = 2.084 cfs Storm frequency = 2 yrs Time to peak = 11 min Time interval = 1 min Hyd. volume = 3,064 cuft Inflow hyd. No. = 2 - Drive Range POST Max. Elevation = 653.66 ft Reservoir name = BioFilter Pond Max. Storage = 2,540 cuft Storage Indication method used. Exfiltration extracted from Outflow. BioFilter Pond Q (cfs) Q (cfs) Hyd. No. 3--2 Year ) 10.00 10.00 8.00 . 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 - 0.00 0 20 40 60 80 100 120 140 160 180 200 Time (min) Hyd No. 3 Hyd No. 2 Total storage used = 2,540 cuft Hydrograph Summary Report 13 Hydraflow Hydrographs by Intelisolve v9.2 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total No. type flow interval peak volume hyd(s) elevation strge used H (origin) (cfs) (min) (min) (cuft) g deescription drogtaph (ft) (tuft) 1 Rational 1.788 1 20 2,865 --- Drive Range PRE 2 Rational 10.85 1 5 4,344 --- Drive Range POST 3 Reservoir 3.089 1 11 3,988 2 653.82 3,142 BioFilter Pond TCSanholdWAHSoptb.gpw Return Period: 10 Year Monday, Jun 24, 2013 Hydrograph Report 14 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 1 Drive Range PRE Hydrograph type = Rational Peak discharge = 1.788 cfs Storm frequency = 10 yrs Time to peak = 20 min Time interval = 1 min Hyd. volume = 2,865 cuft Drainage area = 1.800 ac Runoff coeff. = 0.25 Intensity = 3.974 in/hr Tc by FAA = 20.00 min IDF Curve = Albmrle.IDF Asc/Rec limb fact = 1/1.67 Drive Range PRE Q (cfs) Q cfs Hyd. No. 1 -- 10 Year ( ) 2.00 2.00 1.00 1.00 0.00 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 Hyd No. 1 Time(min) . Hydrograph Report 15 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 2 Drive Range POST Hydrograph type = Rational Peak discharge = 10.85 cfs Storm frequency = 10 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 4,344 cuft Drainage area = 1.800 ac Runoff coeff. = 0.9 Intensity = 6.695 in/hr Tc by FAA = 5.00 min IDF Curve = Albmrle.IDF Asc/Rec limb fact = 1/1.67 Drive Range POST Q (cfs) Q cfs Hyd. No. 2-- 10 Year ( ) 12.00 12.00 10.00 10.00 8.00 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 - 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Hyd No. 2 Time (min) 16 Hydrograph Report Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 3 BioFilter Pond Hydrograph type = Reservoir Peak discharge = 3.089 cfs Storm frequency = 10 yrs Time to peak = 11 min Time interval = 1 min Hyd. volume = 3,988 cuft Inflow hyd. No. = 2 - Drive Range POST Max. Elevation = 653.82 ft Reservoir name = BioFilter Pond Max. Storage = 3,142 cuft Storage Indication method used. Exfiltration extracted from Outflow. BioFilter Pond Q (cfs) cfs Q Hyd. No. 3-- 10 Year (cfs) 12.00 12.00 10.00 10.00 8.00 8.00 6.00 6.00 4.00 4.00 2.00 2.00 0.00 1 - 0.00 0 20 40 60 80 100 120 140 160 180 Time (min) Hyd No. 3 Hyd No. 2 BEM I Total storage used = 3,142 cuft 17 • Hydrograph Summary Report Hydraflow Hydrographs by Intelisolve v9.2 Hyd. Hydrograph Peak Time Time to Hyd. Inflow Maximum Total Hydrograph No. type flow interval peak volume hyd(s) elevation strge used description (origin) (cfs) (min) (min) (cuft) (ft) (cuft) 1 Rational 2.391 1 20 3,831 ---- Drive Range PRE 2 Rational 14.24 1 5 5,702 ---- Drive Range POST 3 Reservoir 5.310 1 10 5,288 2 653.99 3,831 BioFilter Pond TCSanholdWAHSoptb.gpw Return Period: 100 Year Monday, Jun 24, 2013 Hydrograph Report 18 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 1 Drive Range PRE Hydrograph type = Rational Peak discharge = 2.391 cfs Storm frequency = 100 yrs Time to peak = 20 min Time interval = 1 min Hyd. volume = 3,831 cuft Drainage area = 1.800 ac Runoff coeff. = 0.25 Intensity = 5.314 in/hr Tc by FAA = 20.00 min IDF Curve = Albmrle.IDF Asc/Rec limb fact = 1/1.67 Drive Range PRE Q (cfs) Hyd. No. 1 -- 100 Year Q (cfs) 3.00 3.00 2.00 2.00 1.00 1.00 0.00 0.00 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 Hyd No. 1 Time(min) Hydrograph Report 19 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 2 Drive Range POST Hydrograph type = Rational Peak discharge = 14.24 cfs Storm frequency = 100 yrs Time to peak = 5 min Time interval = 1 min Hyd. volume = 5,702 cuft Drainage area = 1.800 ac Runoff coeff. = 0.9 Intensity = 8.788 in/hr Tc by FAA = 5.00 min IDF Curve = Albmrle.IDF Asc/Rec limb fact = 1/1.67 Drive Range POST Q (cfs) Q (cfs) Hyd. No. 2-- 100 Year ) 15.00 15.00 12.00 . 12.00 9.00 9.00 6.00 6.00 3.00 - 3.00 0.00 - - - 0.00 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Time (min) - Hyd No. 2 Hydrograph Report 20 Hydraflow Hydrographs by Intelisolve v9.2 Monday,Jun 24,2013 Hyd. No. 3 BioFilter Pond Hydrograph type = Reservoir Peak discharge = 5.310 cfs Storm frequency = 100 yrs Time to peak = 10 min Time interval = 1 min Hyd. volume = 5,288 cuft Inflow hyd. No. = 2 - Drive Range POST Max. Elevation = 653.99 ft Reservoir name = BioFilter Pond Max. Storage = 3,831 cuft Storage Indication method used. Exfiltration extracted from Outflow. BioFilter Pond Q (cfs) Q cfs Hyd. No. 3 -- 100 Year (cfs) 15.00 15.00 12.00 . 12.00 9.00 - 9.00 6.00 j 6.00 ...:11. . 3.00 3.00 0.00 0.00 0 10 20 30 40 50 60 70 80 90 100 110 120 Time (min) Hyd No. 3 Hyd No. 2 Total storage used = 3,831 cuft