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HomeMy WebLinkAboutSW3170303_Design Calculations_20240701 SITEWORK CALCULATIONS ALLEN STORAGE (ALLEN STORAGE RD, MIDLAND, NC) Prepared by: JONES CIVIL DESIGN Civil Engineering I Land Solutions "From Conception to Completion" **VETERAN-OWNED** (704)412-8523 www.io nesCivilDesignco :Ito% CiaRr�,,i' 'i+i+ +laioaarri, ```` NCA Ri''. .� ,� O ,� .� ,� • •JONES CIVIL; = : Q 1 ' ▪ DESIGN, P.C. : z = = • ,' ' AL rn : C-3859 o : 34936 • • , �Yk- • , EM'', OF A • '', 1A TT H ;%`%-�..,/• ''irra1!WO ?irrarrat%tot' f ALLEN STORAGE SEDIMENT (SKIMMER / TRAP) DESIGN "RISER" (SEDIMENT) BASIN WORKSHEET DESCRIPTION: ALLEN STORAGE (PHASE 2) RISER(SEDIMENT) BASIN #1 Drainage Area to Basin (A) = 20.00 ac. Disturbed Area to Basin (Ad) = 12.00 ac. Weighted Runoff Coefficient (c) = 0.61 Required Basin Volume = 21600.00 ft3 =Ad x 1,800 Provided Volume (at 514.50)ft= 118372.25 ft3 (see table, below) ELEVATION AREA INC. VOLUME ACC. VOLUME 512 43,026 ft2 0.00 ft3 0.00 sq. ft. 513 46,325 ft2 44675.50 ft3 44675.50 sq. ft. 514 49,681 ft2 48003.00 ft3 92678.50 sq. ft. 515 53,094 ft2 51387.50 ft3 144066.00 sq. ft. 516 56,563 ft2 54828.50 ft3 198894.50 sq. ft. SPILLWAY ANALYSIS 10-yr Flow Into Basin (Q10) = 83.69 cfs = (c*I*A); Where"I"=6.86 in/hr Proposed Spillway Elevation = 514.50 ft Proposed Spillway Width (W) = 30.00 ft Flow Height Over Spillway(h) = 0.95 ft = [Q10/ (3 *W)]213 TRAPPING EFFICIENCY (75% Trapping Efficiency Per the Barfield and Clar Equation) Surface Area Required at Design Flow=435 * Q10 = 36406.02 ft2 Surface Area Provided at Design Flow (see table) = 51387.50 ft2 SKIMMER SIZING Volume = 21600.00 ft3 (Released Over 5.0 days) Table 6.64a(NCDENR) Flow (Qd) = (21600.00 ft3/ 5 days) =4320 ft3/day Skimmer Size Head Chosen Skimmer Size = 2.50 in Thus, Head (H) = 0.208 ft 1.5 in 0.125 ft Desired Orifice Diameter = [Qd/(2300 * (H)112)]112 = 2.03 in 2 in 0.167 ft Therefore, Use 2.0 in. Orifice 2.5 in 0.208 ft 3 in 0.250 ft 4 in 0.292 ft 5 in 0.333 ft 6 in 0.417 ft 8 in 0.500 ft ALLEN STORAGE STORM DRAIN (PIPE SIZING a rn o ca s _ _ Ul _ _ _ cn , J r CO CO CO 0 CO r Co W 000 V co C n N _ Q V Co O I� Co r O - C7 00 O O O O a Lfl O )- LO Co LO LO LNf) LNf) LO LO LO LO O N LO LO LO LO LO E O o o O LO o V O O O (T 6) O N N • O. 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I- 0 CO O O V CO N CO CO O C) (A O CM •- C C (0 0 O LO 00 N.: r V V 4 CO V Ns: Loci CL) J 4) — LO C3 CO CO 0 I� CO CO N N V CO O 7 ›- -I O 0 0 0 O 0 LO LO 0 LO 0 LO 0 LO LO 0 �� d C 0) LO O I� CO O CO N CO CM O CO CO a N 00 LO LO CO V LO 0) O LO (Li N.: N- (LiO O C LO LO LO LO LO LO LO LO LN LO LO LO LO LO LNf) Cl) Q C t+ O co O co O O LO LO co LO co LO co o O D O a_ N LO LOLO (0 LO O C) N O 00 CO O (0 N 0 - o-i O O O O N CO OCC C N N N - LO LO LO LO LO LO LO LO LC) LO LO LO LO LO LO 0) To y co Co co Co co co co co CO co CO co Co Co co 0 2' O O 0 O 0 0 O 0 O 0 O 0 O O 0 C - o 0 0 0 0 0 0 0 0 0 0 (a 0 0 0 0 rn C O. U U U U U U U U U U U U U U U + J H Cl) E i C N E N N N N co Co 00 - - OM coam N a0 Lo co — Q) NCo O o N o r O O O in M 00 N W CO O O N N N O cci Q CO N N 66 6 66 N N 66 66 N N - II V/ }� C 0 o. Q f2 Q 0_ 0_ Q Q Q Q Q Q Q Q 0-J - d d d d d d d a a a a a a a a LLL...LLL •� 0 c al N a) c 11 c) cO L Co N Co LO CO r o O O NCO 4 LO O I- 0 0 J Z d 7 ALLEN STORAGE SWALE (OPEN CHANNEL) ANALYSIS OPEN-CHANNEL FLOW WORKSHEET PROJECT: ALLEN STORAGE (PHASE 2) Description: DIVERSION TD-1 FACTORS USED: TIME OF CONCENTRATION (Tc): 5 min. DESIGN STORM EVENT FREQUENCY: 10-yr RAINFALL INTENSITY("I"): 7.38 in/hr DRAINAGE AREA ("A"): 2.75 ac RUNOFF COEFFICIENT("c"): 0.60 FLOW FROM DRAINAGE AREA (Q=c*I*A): 12.18 cfs ADDITIONAL FLOW(or user-defined flow): CHANNEL CHARACTERISTICS: CHANNEL LENGTH: 429.00 ft CHANNEL BOTTOM WIDTH: 0.50 ft CHANNEL SLOPE: 0.015 ft/ft CHANNEL SIDE SLOPES: 3 :1 CHANNEL LINING MATERIAL: Unvegetated Permanent Liner(P300) MANNING'S n-VALUE: 0.027 ANALYSIS OF CHANNEL BOTTOM: VEGETATIVE GROWTH FORM= BUNCH Total Depth of Area of Wetted Hydraulic Calculated Allowable Velocity , Flow Rate Flow Flow Perimeter Radius V Shear Shear (Q) (D) (Af) ( Pw) ( R ) ( ) Stress Stress 12.18 cfs 0.92' 2.97 sq. ft. 6.29' 0.47 ft 4.10 fps 0.86 psf 2.00 psf ALLOWABLE SHEAR STRESS IS GREATER THAN THE CALCULATED SHEAR STRESS;THEREFORE, CHANNEL BOTTOM WILL BE STABLE Effective shear stress and permissible shear stresses were computed as described in the Hydraulic Engineering Circular No.15,Third Edition,Design of Roadside Channels with Flexible Linings,September 2005 as produced by the U.S.Department of Transportation,Federal Highway Administration,National Highway Institute OPEN-CHANNEL FLOW WORKSHEET PROJECT: ALLEN STORAGE (PHASE 2) Description: DIVERSION TD-2 FACTORS USED: TIME OF CONCENTRATION (Tc): 5 min. DESIGN STORM EVENT FREQUENCY: 10-yr RAINFALL INTENSITY("I"): 7.38 in/hr DRAINAGE AREA ("A"): 1.98 ac RUNOFF COEFFICIENT("c"): 0.60 FLOW FROM DRAINAGE AREA (Q=c*I*A): 8.77 cfs ADDITIONAL FLOW(or user-defined flow): CHANNEL CHARACTERISTICS: CHANNEL LENGTH: 238.00 ft CHANNEL BOTTOM WIDTH: 0.50 ft CHANNEL SLOPE: 0.015 ft/ft CHANNEL SIDE SLOPES: 3 :1 CHANNEL LINING MATERIAL: Unvegetated Permanent Liner(P300) MANNING'S n-VALUE: 0.027 ANALYSIS OF CHANNEL BOTTOM: VEGETATIVE GROWTH FORM= BUNCH Total Depth of Area of Wetted Hydraulic Calculated Allowable Velocity , Flow Rate Flow Flow Perimeter Radius V Shear Shear (Q) (D) (Af) ( Pw) ( R ) ( ) Stress Stress 8.77 cfs 0.80' 2.33 sq. ft. 5.57' 0.42 ft 3.76 fps 0.75 psf 2.00 psf ALLOWABLE SHEAR STRESS IS GREATER THAN THE CALCULATED SHEAR STRESS;THEREFORE, CHANNEL BOTTOM WILL BE STABLE Effective shear stress and permissible shear stresses were computed as described in the Hydraulic Engineering Circular No.15,Third Edition,Design of Roadside Channels with Flexible Linings,September 2005 as produced by the U.S.Department of Transportation,Federal Highway Administration,National Highway Institute OPEN-CHANNEL FLOW WORKSHEET PROJECT: ALLEN STORAGE (PHASE 2) Description: SWALE "S1" FACTORS USED: TIME OF CONCENTRATION (Tc): 5 min. DESIGN STORM EVENT FREQUENCY: 10-yr RAINFALL INTENSITY("I"): 7.38 in/hr DRAINAGE AREA ("A"): 6.20 ac RUNOFF COEFFICIENT("c"): 0.45 FLOW FROM DRAINAGE AREA (Q=c*I*A): 20.59 cfs ADDITIONAL FLOW(or user-defined flow): CHANNEL CHARACTERISTICS: CHANNEL LENGTH: 118.00 ft CHANNEL BOTTOM WIDTH: 1.00 ft CHANNEL SLOPE: 0.015 ft/ft CHANNEL SIDE SLOPES: 3 :1 CHANNEL LINING MATERIAL: Fully Vegetated Perm. Liner(P300) MANNING'S n-VALUE: 0.027 ANALYSIS OF CHANNEL BOTTOM: VEGETATIVE GROWTH FORM= BUNCH Total Depth of Area of Wetted Hydraulic Calculated Allowable Velocity , Flow Rate Flow Flow Perimeter Radius V Shear Shear (Q) (D) (Af) ( Pw) ( R ) ( ) Stress Stress 20.59 cfs 1.05' 4.38 sq. ft. 7.66' 0.57 ft 4.70 fps 0.99 psf 8.00 psf ALLOWABLE SHEAR STRESS IS GREATER THAN THE CALCULATED SHEAR STRESS;THEREFORE, CHANNEL BOTTOM WILL BE STABLE Effective shear stress and permissible shear stresses were computed as described in the Hydraulic Engineering Circular No.15,Third Edition,Design of Roadside Channels with Flexible Linings,September 2005 as produced by the U.S.Department of Transportation,Federal Highway Administration,National Highway Institute OPEN-CHANNEL FLOW WORKSHEET PROJECT: ALLEN STORAGE (PHASE 2) Description: SWALE "S2" FACTORS USED: TIME OF CONCENTRATION (Tc): 5 min. DESIGN STORM EVENT FREQUENCY: 10-yr RAINFALL INTENSITY("I"): 7.38 in/hr DRAINAGE AREA ("A"): 3.41 ac RUNOFF COEFFICIENT("c"): 0.50 FLOW FROM DRAINAGE AREA (Q=C*I*A): 12.58 cfs ADDITIONAL FLOW(or user-defined flow): CHANNEL CHARACTERISTICS: CHANNEL LENGTH: 329.00 ft CHANNEL BOTTOM WIDTH: 1.00 ft CHANNEL SLOPE: 0.045 ft/ft CHANNEL SIDE SLOPES: 3 :1 CHANNEL LINING MATERIAL: Fully Vegetated Perm. Liner(P300) MANNING'S n-VALUE: 0.027 ANALYSIS OF CHANNEL BOTTOM: VEGETATIVE GROWTH FORM= BUNCH Total Depth of Area of Wetted Hydraulic Calculated Allowable Velocity , Flow Rate Flow Flow Perimeter Radius V Shear Shear (Q) (D) (Af) ( Pw) ( R ) ( ) Stress Stress 12.58 cfs 0.67' 2.02 sq. ft. 5.24' 0.39 ft 6.23 fps 1.88 psf 8.00 psf ALLOWABLE SHEAR STRESS IS GREATER THAN THE CALCULATED SHEAR STRESS;THEREFORE, CHANNEL BOTTOM WILL BE STABLE Effective shear stress and permissible shear stresses were computed as described in the Hydraulic Engineering Circular No.15,Third Edition,Design of Roadside Channels with Flexible Linings,September 2005 as produced by the U.S.Department of Transportation,Federal Highway Administration,National Highway Institute OPEN-CHANNEL FLOW WORKSHEET PROJECT: ALLEN STORAGE (PHASE 2) Description: SWALE "S3" FACTORS USED: TIME OF CONCENTRATION (Tc): 5 min. DESIGN STORM EVENT FREQUENCY: 10-yr RAINFALL INTENSITY("I"): 7.38 in/hr DRAINAGE AREA ("A"): 1.03 ac RUNOFF COEFFICIENT("c"): 0.50 FLOW FROM DRAINAGE AREA (Q=c*I*A): 3.80 cfs ADDITIONAL FLOW(or user-defined flow): CHANNEL CHARACTERISTICS: CHANNEL LENGTH: 549.00 ft CHANNEL BOTTOM WIDTH: 0.50 ft CHANNEL SLOPE: 0.015 ft/ft CHANNEL SIDE SLOPES: 3 :1 CHANNEL LINING MATERIAL: Unvegetated Permanent Liner(P300) MANNING'S n-VALUE: 0.027 ANALYSIS OF CHANNEL BOTTOM: VEGETATIVE GROWTH FORM= BUNCH Total Depth of Area of Wetted Hydraulic Calculated Allowable Velocity , Flow Rate Flow Flow Perimeter Radius V Shear Shear (Q) (D) (Af) ( Pw) ( R ) ( ) Stress Stress 3.80 cfs 0.56' 1.23 sq. ft. 4.06' 0.30 ft 3.08 fps 0.53 psf 2.00 psf ALLOWABLE SHEAR STRESS IS GREATER THAN THE CALCULATED SHEAR STRESS;THEREFORE, CHANNEL BOTTOM WILL BE STABLE Effective shear stress and permissible shear stresses were computed as described in the Hydraulic Engineering Circular No.15,Third Edition,Design of Roadside Channels with Flexible Linings,September 2005 as produced by the U.S.Department of Transportation,Federal Highway Administration,National Highway Institute OPEN-CHANNEL FLOW WORKSHEET PROJECT: ALLEN STORAGE (PHASE 2) Description: SWALE "S4" FACTORS USED: TIME OF CONCENTRATION (Tc): 5 min. DESIGN STORM EVENT FREQUENCY: 10-yr RAINFALL INTENSITY("I"): 7.38 in/hr DRAINAGE AREA ("A"): 3.45 ac RUNOFF COEFFICIENT("c"): 0.50 FLOW FROM DRAINAGE AREA (Q=c*I*A): 12.73 cfs ADDITIONAL FLOW(or user-defined flow): CHANNEL CHARACTERISTICS: CHANNEL LENGTH: 464.00 ft CHANNEL BOTTOM WIDTH: 2.00 ft CHANNEL SLOPE: 0.010 ft/ft CHANNEL SIDE SLOPES: 3 :1 CHANNEL LINING MATERIAL: Unvegetated Permanent Liner(P300) MANNING'S n-VALUE: 0.027 ANALYSIS OF CHANNEL BOTTOM: VEGETATIVE GROWTH FORM= BUNCH Total Depth of Area of Wetted Hydraulic Calculated Allowable Velocity , Flow Rate Flow Flow Perimeter Radius V Shear Shear (Q) (D) (Af) ( Pw) ( R ) ( ) Stress Stress 12.73 cfs 0.82' 3.63 sq. ft. 7.17' 0.51 ft 3.50 fps 0.51 psf 2.00 psf ALLOWABLE SHEAR STRESS IS GREATER THAN THE CALCULATED SHEAR STRESS;THEREFORE, CHANNEL BOTTOM WILL BE STABLE Effective shear stress and permissible shear stresses were computed as described in the Hydraulic Engineering Circular No.15,Third Edition,Design of Roadside Channels with Flexible Linings,September 2005 as produced by the U.S.Department of Transportation,Federal Highway Administration,National Highway Institute OPEN-CHANNEL FLOW WORKSHEET PROJECT: ALLEN STORAGE (PHASE 2) Description: SWALE "B2" FACTORS USED: TIME OF CONCENTRATION (Tc): 21 min. DESIGN STORM EVENT FREQUENCY: 10-yr RAINFALL INTENSITY("I"): 4.29 in/hr DRAINAGE AREA ("A"): 8.16 ac RUNOFF COEFFICIENT("c"): 0.40 FLOW FROM DRAINAGE AREA (Q=c*I*A): 14.00 cfs ADDITIONAL FLOW(or user-defined flow): CHANNEL CHARACTERISTICS: CHANNEL LENGTH: 80.00 ft CHANNEL BOTTOM WIDTH: 2.00 ft CHANNEL SLOPE: 0.015 ft/ft CHANNEL SIDE SLOPES: 3 :1 CHANNEL LINING MATERIAL: Unvegetated Permanent Liner(P300) MANNING'S n-VALUE: 0.027 ANALYSIS OF CHANNEL BOTTOM: VEGETATIVE GROWTH FORM= BUNCH Total Depth of Area of Wetted Hydraulic Calculated Allowable Velocity , Flow Rate Flow Flow Perimeter Radius V Shear Shear (Q) (D) (Af) ( Pw) ( R ) ( ) Stress Stress 14.00 cfs 0.78' 3.36 sq. ft. 6.91' 0.49 ft 4.17 fps 0.73 psf 2.00 psf ALLOWABLE SHEAR STRESS IS GREATER THAN THE CALCULATED SHEAR STRESS;THEREFORE, CHANNEL BOTTOM WILL BE STABLE Effective shear stress and permissible shear stresses were computed as described in the Hydraulic Engineering Circular No.15,Third Edition,Design of Roadside Channels with Flexible Linings,September 2005 as produced by the U.S.Department of Transportation,Federal Highway Administration,National Highway Institute OPEN-CHANNEL FLOW WORKSHEET PROJECT: ALLEN STORAGE (PHASE 2) Description: SWALE "S5" FACTORS USED: TIME OF CONCENTRATION (Tc): 5 min. DESIGN STORM EVENT FREQUENCY: 10-yr RAINFALL INTENSITY("I"): 7.38 in/hr DRAINAGE AREA ("A"): 0.08 ac RUNOFF COEFFICIENT("c"): 0.60 FLOW FROM DRAINAGE AREA (Q=c*I*A): 0.35 cfs ADDITIONAL FLOW(or user-defined flow): CHANNEL CHARACTERISTICS: CHANNEL LENGTH: 238.00 ft CHANNEL BOTTOM WIDTH: 0.50 ft CHANNEL SLOPE: 0.015 ft/ft CHANNEL SIDE SLOPES: 3 :1 CHANNEL LINING MATERIAL: Unvegetated Permanent Liner(P300) MANNING'S n-VALUE: 0.034 ANALYSIS OF CHANNEL BOTTOM: VEGETATIVE GROWTH FORM= BUNCH Total Depth of Area of Wetted Hydraulic Calculated Allowable Velocity , Flow Rate Flow Flow Perimeter Radius V Shear Shear (Q) (D) (Af) ( Pw) ( R ) ( ) Stress Stress 0.35 cfs 0.22' 0.25 sq. ft. 1.88' 0.13 ft 1.40 fps 0.20 psf 2.00 psf ALLOWABLE SHEAR STRESS IS GREATER THAN THE CALCULATED SHEAR STRESS;THEREFORE, CHANNEL BOTTOM WILL BE STABLE Effective shear stress and permissible shear stresses were computed as described in the Hydraulic Engineering Circular No.15,Third Edition,Design of Roadside Channels with Flexible Linings,September 2005 as produced by the U.S.Department of Transportation,Federal Highway Administration,National Highway Institute ALLEN STORAGE STORM WATER BASIN DESIGN WET POND WORKSHEET ALLEN STORAGE I SCM #2 (Wet Pond) April 29,2024 Total Drainage Area (AD) = 20.31 ac. Total Impervious Area (Ai) = 8.69 ac. Impervious Fraction (IA) = 0.43 =Impervious Area (Ai) / Total Drainage Area (A) Runoff Coefficient (Rv) = 0.44 =0.05+0.9*l,, [Per NC DEQ Stormwater Manual] DESIGN VOLUME (DV) TO BE TREATED (per NC DEQ Stormwater Manual, Section B) Volume (V)to be controlled = (3630* RD* Rv*AD) Where: RD = Design Storm Depth = 1 inch AD = Watershed Area = 20.31 Ac Thus, the Design Volume (DV) = 32,439.13 ft3 WET POND MAIN POOL SIZING (per NC DEQ Stormwater Manual, Section C-3) The Minimum Required Main Pool Volume (VMP) = 0.87 * (HRT/Ts) * DV, where: Where: DV= Design Volume = 32,439.13 ft3 HRT = Hydraulic Residence Time = 14 days Ts =Avg. Time Between Storms = 5 days 0.87 = Factor to Adjust for the Volume in the Forebay Thus, Min. VMP = [0.87 * (14/5) * 32,439.13 ft3] = 79,021.73 ft3 Volume provided at Elev. =514.23 ft (See the Wet Pond"Main Pool"Table,below) The lowest primary outlet will begin at 516.00 ft Thus, the Permanent Pool elevation will be maintained at 516.00 ft WET POND "MAIN POOL" (VOLUME) BELOW PERMANENT POOL ELEVATION INCREMENTAL AREA INCREMENTAL VOLUME BASIN CUMULATIVE VOLUME 512.00 ft 33120 ft2 0 ft3 0 ft3 513.00 ft 35098 ft2 34109 ft3 34109 ft3 514.00 ft 37090 ft2 _ 36094 ft3 70203 ft3 515.00 ft 39107 ft2 38099 ft3 108302 ft3 516.00 ft 43217 ft2 41162 ft3 149464 ft3 517.00 ft 47961 ft2 45589 ft3 195053 ft3 AVERAGE DEPTH CALCULATION (per NC DEQ Stormwater Manual, Section C-3, MDC 2) The "Average Depth" (DAVG) of the Main Pool shall be 3'to 8' below permanent pool. (Perm. Pool=516.00 ft) DAvG is computed by: (VPP/APP), where: VPP = Volume of Permanent Pool; APP =Area of Permanent Pool Since VPP = 149,463.50 ft3 &since APP = 47,961 ft2 Then, DAvG = 3.12 ft Above the Permanent Pool, the DV (32,439.13 ft3) is provided at Elevation =516.71 ft (See the"Stage-Storage"Table,below) Therefore, the "secondary"outlet will begin at 516.75 ft SA/ DA RATIO CALCULATION (per NC DEQ Stormwater Manual, Section C-3, MDC 2) Percent Impervious Cover=43.0% Per NC DEQ Table 1 (MDC C-3),the SA/DA Ratio= 1.594 Permanent Pool Average Depth = 3.1 ft Thus,the required Surface Area = 14,102 ft2 For this pond, the proposed Surface Area =47,961 ft2 WET POND STAGE-STORAGE (VOLUME) ABOVE PERMANENT POOL ELEVATION SURFACE AREA INCREMENTAL VOLUME BASIN CUMULATIVE VOLUME 516.00 ft 43217 ft2 O ft3 _ O ft3 517.00 ft 47961 ft2 45589 ft3 45589 ft3 518.00 ft 63772 ft2 55867 ft3 101456 ft3 519.00 ft 67425 ft2 65599 ft3 167054 ft3 520.00 ft 71134 ft2 69280 ft3 236334 ft3 521.00 ft 74900 ft2 73017 ft3 309351 ft3 `Proposed Basin"Top of Dam"=520.50 ft FOREBAY SIZING (BELOW PERMANENT POOL ELEVATION) ELEVATION SURFACE AREA INCREMENTAL VOLUME FOREBAY CUMULATIVE VOLUME 513.00 ft 5022 ft2 0 ft3 0 ft3 514.00 ft 6222 ft2 5622 ft3 5622 ft3 515.00 ft i 7440 ft2 6831 ft3 12453 ft3 516.00 ft 8896 ft2 8168 ft3 20621 ft3 517.00 ft 10479 ft2 9688 ft3 30309 ft3 521.00 ft *Forebay is 15.54% of the main pool volume RELEASE RATE & ORIFICE-SIZING ("DRAWDOWN") CALCULATIONS The Design Volume (DV) shall be released over a total time period of 48 hours Based on this release-rate, size the max. orifice diameter using the orifice equation: Q = c*A* (2*g*h)0.5 Where: Q = Flow Through Orifice (in "cfs") = 0.188 cfs (32,439.13 ft3 released over 48 hrs) c = Orifice Coefficient = 0.6 A = Cross-Sectional Area of Orifice Opening (in ft2) = Tr* R2 Tr= 3.14159 R = Radius of Orifice Opening (in "ft") = D/2 D = Diameter of Orifice Opening (in "ft") g = Gravitational Constant = 32.2 ft/sec2 h =Average Height of Water Above Orifice (in "ft") Algebraically, the orifice flow equation can be rearranged to solve for diameter(D)=[4Q/(Tr* c* (2gh)(15))0.5 So (for DV), the Max. Orifice (D) = 0.29 ft = 3.46 in. POND ROUTING RESULTS (using Hydra flow Hydrographs®) EVENT Pre-Dev.Runoff Total Post-Dev Peak Stage Comments: Discharge (within Basin/Pond) 2-yr 8.554 cfs 4.106 cfs 517.19 ft POST Discharge < PRE Discharge _ 10-yr 25.83 cfs 15.750 cfs 517.91 ft POST Discharge < PRE Discharge 25-yr 38.17 cfs 17.450 cfs 518.42 ft Peak stage is 2.08 ft below Top of Dam 100-yr 59.88 cfs 42.880 cfs 519.02 ft Peak stage is 1.48 ft below Top of Dam ALLEN STORAGE STORM WATER (HYDROGRAPHS) ROUTING Hydraflow Table of Contents Hydro-22018.gpw Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Watershed Model Schematic 1 Hydrograph Return Period Recap 2 2 - Year Summary Report 3 Hydrograph Reports 4 Hydrograph No. 1, SCS Runoff, Developed Area 2 4 TR-55 Tc Worksheet 5 Hydrograph No. 2, Reservoir, Basin 2 6 Pond Report - Basin 2 7 Hydrograph No. 3, SCS Runoff, Pre-West 8 TR-55 Tc Worksheet 9 Hydrograph No. 4, SCS Runoff, Pre-East 10 TR-55 Tc Worksheet 11 Hydrograph No. 5, SCS Runoff, Bypass 2 12 Hydrograph No. 6, Combine, POST-East 13 Hydrograph No. 7, SCS Runoff, Developed Area 1 14 Hydrograph No. 8, Reservoir, Basin 1 15 Pond Report - Basin 1 16 Hydrograph No. 9, SCS Runoff, Bypass 1 17 TR-55 Tc Worksheet 18 Hydrograph No. 10, Combine, POST-West 19 10 - Year Summary Report 20 Hydrograph Reports 21 Hydrograph No. 1, SCS Runoff, Developed Area 2 21 Hydrograph No. 2, Reservoir, Basin 2 22 Hydrograph No. 3, SCS Runoff, Pre-West 23 Hydrograph No. 4, SCS Runoff, Pre-East 24 Hydrograph No. 5, SCS Runoff, Bypass 2 25 Hydrograph No. 6, Combine, POST-East 26 Hydrograph No. 7, SCS Runoff, Developed Area 1 27 Hydrograph No. 8, Reservoir, Basin 1 28 Hydrograph No. 9, SCS Runoff, Bypass 1 29 Hydrograph No. 10, Combine, POST-West 30 25 - Year Summary Report 31 Hydrograph Reports 32 Hydrograph No. 1, SCS Runoff, Developed Area 2 32 Hydrograph No. 2, Reservoir, Basin 2 33 Hydrograph No. 3, SCS Runoff, Pre-West 34 Hydrograph No. 4, SCS Runoff, Pre-East 35 Hydrograph No. 5, SCS Runoff, Bypass 2 36 Hydrograph No. 6, Combine, POST-East 37 Hydrograph No. 7, SCS Runoff, Developed Area 1 38 Contents continued... Hydro-22018.gpw Hydrograph No. 8, Reservoir, Basin 1 39 Hydrograph No. 9, SCS Runoff, Bypass 1 40 Hydrograph No. 10, Combine, POST-West 41 100 - Year Summary Report 42 Hydrograph Reports 43 Hydrograph No. 1, SCS Runoff, Developed Area 2 43 Hydrograph No. 2, Reservoir, Basin 2 44 Hydrograph No. 3, SCS Runoff, Pre-West 45 Hydrograph No. 4, SCS Runoff, Pre-East 46 Hydrograph No. 5, SCS Runoff, Bypass 2 47 Hydrograph No. 6, Combine, POST-East 48 Hydrograph No. 7, SCS Runoff, Developed Area 1 49 Hydrograph No. 8, Reservoir, Basin 1 50 Hydrograph No. 9, SCS Runoff, Bypass 1 51 Hydrograph No. 10, Combine, POST-West 52 IDF Report 53 1 Watershed Model Schematic Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 ass 1 II,ePOST-West Developed Area 1 fp Pre-West asin 1 ■ POST-East lirasin ypass 2 Pre-East CD De4loped •eitit Legend Hyd. Origin Description 1 SCS Runoff Developed Area 2 2 Reservoir Basin 2 3 SCS Runoff Pre-West 4 SCS Runoff Pre-East 5 SCS Runoff Bypass 2 6 Combine POST-East 7 SCS Runoff Developed Area 1 8 Reservoir Basin 1 9 SCS Runoff Bypass 1 10 Combine POST-West Project: Hydro-22018.gpw Monday, 04/29/2024 2 Hydrograph Return Period Recap Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Hyd. Hydrograph Inflow Peak Outflow(cfs) Hydrograph No. type hyd(s) Description (origin) 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr 1 SCS Runoff 29.71 56.81 74.03 102.32 Developed Area 2 2 Reservoir I 1 3.830 16.53 17.85 41.11 I Basin 2 3 SCS Runoff 35.73 93.94 134.15 204.15 Pre-West 4 SCS Runoff 8.554 25.83 38.17 59.88 I Pre-East 5 SCS Runoff 3.424 9.151 13.11 19.99 Bypass 2 6 Combine 2, 5 4.106 17.41 19.10 42.96 POST-East 7 SCS Runoff 45.00 81.45 104.17 141.08 Developed Area 1 8 Reservoir 7 0.397 5.237 13.03 36.93 Basin 1 9 SCS Runoff 15.82 47.66 70.33 110.21 Bypass 1 10 Combine 8,9 15.82 49.58 83.05 146.46 POST-West Proj. file: Hydro-22018.gpw Monday, 04/29/2024 3 Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 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 29.71 2 730 111,424 Developed Area 2 2 Reservoir 3.830 2 780 104,692 1 517.19 55,955 Basin 2 3 SCS Runoff 35.73 2 728 149,150 Pre-West 4 SCS Runoff 8.554 2 732 42,305 Pre-East 5 SCS Runoff 3.424 2 718 7,564 Bypass 2 6 Combine 4.106 2 776 112,256 2,5 POST-East 7 SCS Runoff 45.00 2 718 90,660 Developed Area 1 8 Reservoir 0.397 2 1442 35,682 7 516.06 77,502 Basin 1 9 SCS Runoff 15.82 2 730 73,135 Bypass 1 10 Combine 15.82 2 730 108,817 8,9 POST-West Hydro-22018.gpw Return Period: 2 Year Monday, 04/29/2024 4 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 1 Developed Area 2 Hydrograph type = SCS Runoff Peak discharge = 29.71 cfs Storm frequency = 2 yrs Time to peak = 730 min Time interval = 2 min Hyd. volume = 111,424 cuft Drainage area = 20.310 ac Curve number = 77* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 24.80 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(8.690 x 98)+(11.620 x 61)]/20.310 Developed Area 2 Q (cfs) Hyd. No. 1 -- 2 Year Q (cfs) 30.00 30.00 25.00 25.00 20.00 20.00 15.00 15.00 10.00 10.00 5.00 5.00 0.00 — 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 1 Time (min) 5 TR55 Tc Worksheet Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Hyd. No. 1 Developed Area 2 Description A B C Totals Sheet Flow Manning's n-value = 0.240 0.011 0.011 Flow length (ft) = 150.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.64 0.00 0.00 Land slope (%) = 1.40 0.00 0.00 Travel Time (min) = 21.34 + 0.00 + 0.00 = 21.34 Shallow Concentrated Flow Flow length (ft) = 600.00 0.00 0.00 Watercourse slope (%) = 3.20 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) =2.89 0.00 0.00 Travel Time (min) = 3.46 + 0.00 + 0.00 = 3.46 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 0.0 Travel Time (min) = 0.00 + 0.00 + 0.00 = 0.00 Total Travel Time, Tc 24.80 min 6 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 2 Basin 2 Hydrograph type = Reservoir Peak discharge = 3.830 cfs Storm frequency = 2 yrs Time to peak = 780 min Time interval = 2 min Hyd. volume = 104,692 cuft Inflow hyd. No. = 1 - Developed Area 2 Max. Elevation = 517.19 ft Reservoir name = Basin 2 Max. Storage = 55,955 cuft Storage Indication method used. Basin 2 Q (cfs) Hyd. No. 2 -- 2 Year Q (cfs) 30.00 I _ 30.00 25.00 25.00 20.00 20.00 15.00 15.00 10.00 10.00 5.00 5.00 0.00 — 0.00 0 600 1200 1800 2400 3000 3600 4200 4800 5400 6000 Time (min) Hyd No. 2 Hyd No. 1 111111111 Total storage used = 55,955 cuft Pond Report 7 Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Pond No. 1 - Basin 2 Pond Data Contours-User-defined contour areas.Conic method used for volume calculation.Begining Elevation=516.00 ft Stage/Storage Table Stage(ft) Elevation(ft) Contour area(sqft) Incr.Storage(cuft) Total storage(cuft) 0.00 516.00 43,217 0 0 1.00 517.00 47,961 45,564 45,564 2.00 518.00 63,772 55,674 101,237 3.00 519.00 67,425 65,584 166,821 4.00 520.00 71,134 69,264 236,085 5.00 521.00 74,900 73,002 309,087 Culvert/Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise(in) = 18.00 3.00 0.00 0.00 Crest Len(ft) = 4.00 16.00 20.00 0.00 Span(in) = 18.00 3.00 0.00 0.00 Crest El.(ft) = 516.75 517.50 518.50 0.00 No.Barrels = 1 1 0 0 Weir Coeff. = 3.10 3.10 3.10 3.33 Invert El.(ft) = 513.20 516.00 0.00 0.00 Weir Type = Broad Broad Broad --- Length(ft) = 57.00 0.00 0.00 0.00 Multi-Stage = Yes Yes No No Slope(%) = 0.71 0.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000(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 Elev(ft) 5.00 521.00 4.00 520.00 3.00 519.00 2.00 518.00 1.00 517.00 0.00 516.00 0.0 30.0 60.0 90.0 120.0 150.0 180.0 210.0 240.0 270.0 Total Q Discharge(cfs) 8 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 3 Pre-West Hydrograph type = SCS Runoff Peak discharge = 35.73 cfs Storm frequency = 2 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 149,150 cuft Drainage area = 51.950 ac Curve number = 64* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.20 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(4.530 x 98)+(47.420 x 61)]/51.950 Pre-West Q (cfs) Hyd. No. 3 -- 2 Year Q (cfs) 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 — 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Time (min) — Hyd No. 3 9 TR55 Tc Worksheet Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Hyd. No. 3 Pre-West Description A B C Totals Sheet Flow Manning's n-value = 0.240 0.011 0.011 Flow length (ft) = 150.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.64 0.00 0.00 Land slope (%) = 2.00 0.00 0.00 Travel Time (min) = 18.51 + 0.00 + 0.00 = 18.51 Shallow Concentrated Flow Flow length (ft) = 628.00 0.00 0.00 Watercourse slope (%) = 5.70 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) =3.85 0.00 0.00 Travel Time (min) = 2.72 + 0.00 + 0.00 = 2.72 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 0.0 Travel Time (min) = 0.00 + 0.00 + 0.00 = 0.00 Total Travel Time, Tc 21.20 min 10 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 4 Pre-East Hydrograph type = SCS Runoff Peak discharge = 8.554 cfs Storm frequency = 2 yrs Time to peak = 732 min Time interval = 2 min Hyd. volume = 42,305 cuft Drainage area = 18.590 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 26.50 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Pre-East Q (cfs) Hyd. No. 4 -- 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 1111111111i , 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 4 Time (min) 11 TR55 Tc Worksheet Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Hyd. No. 4 Pre-East Description A B C Totals Sheet Flow Manning's n-value = 0.240 0.011 0.011 Flow length (ft) = 150.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.64 0.00 0.00 Land slope (%) = 1.40 0.00 0.00 Travel Time (min) = 21.34 + 0.00 + 0.00 = 21.34 Shallow Concentrated Flow Flow length (ft) = 798.00 0.00 0.00 Watercourse slope (%) = 2.60 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) =2.60 0.00 0.00 Travel Time (min) = 5.11 + 0.00 + 0.00 = 5.11 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 0.0 Travel Time (min) = 0.00 + 0.00 + 0.00 = 0.00 Total Travel Time, Tc 26.50 min 12 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 5 Bypass 2 Hydrograph type = SCS Runoff Peak discharge = 3.424 cfs Storm frequency = 2 yrs Time to peak = 718 min Time interval = 2 min Hyd. volume = 7,564 cuft Drainage area = 3.490 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Bypass 2 Q (cfs) Hyd. No. 5 -- 2 Year Q (cfs) 4.00 - 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 — 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Time (min) — Hyd No. 5 13 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 6 POST-East Hydrograph type = Combine Peak discharge = 4.106 cfs Storm frequency = 2 yrs Time to peak = 776 min Time interval = 2 min Hyd. volume = 112,256 cuft Inflow hyds. = 2, 5 Contrib. drain. area = 3.490 ac POST-East Q (cfs) Hyd. No. 6 -- 2 Year Q (cfs) 5.00 5.00 4.00 4.00 3.00 3.00 2.00 2.00 1.00 1.00 0.00 - 0.00 0 600 1200 1800 2400 3000 3600 4200 4800 5400 6000 Time (min) Hyd No. 6 Hyd No. 2 Hyd No. 5 14 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 7 Developed Area 1 Hydrograph type = SCS Runoff Peak discharge = 45.00 cfs Storm frequency = 2 yrs Time to peak = 718 min Time interval = 2 min Hyd. volume = 90,660 cuft Drainage area = 15.900 ac Curve number = 79* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(7.560 x 98)+(8.340 x 61)]/15.900 Developed Area 1 Q (cfs) Hyd. No. 7 -- 2 Year Q (cfs) 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 1 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 7 Time (min) 15 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 8 Basin 1 Hydrograph type = Reservoir Peak discharge = 0.397 cfs Storm frequency = 2 yrs Time to peak = 1442 min Time interval = 2 min Hyd. volume = 35,682 cuft Inflow hyd. No. = 7 - Developed Area 1 Max. Elevation = 516.06 ft Reservoir name = Basin 1 Max. Storage = 77,502 cuft Storage Indication method used. Basin 1 Q (cfs) Hyd. No. 8 -- 2 Year Q (cfs) 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 0.00 0 600 1200 1800 2400 3000 3600 4200 4800 5400 6000 Time (min) Hyd No. 8 Hyd No. 7 111111111 Total storage used = 77,502 cuft Pond Report 16 Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Pond No. 2 - Basin 1 Pond Data Contours-User-defined contour areas.Conic method used for volume calculation.Begining Elevation=511.00 ft Stage/Storage Table Stage(ft) Elevation(ft) Contour area(sqft) Incr.Storage(cuft) Total storage(cuft) 0.00 511.00 10,514 0 0 1.00 512.00 11,872 11,185 11,185 2.00 513.00 13,256 12,556 23,741 3.00 514.00 14,665 13,953 37,695 4.00 515.00 19,042 16,804 54,499 5.00 516.00 24,039 21,490 75,989 6.00 517.00 26,435 25,225 101,214 7.00 518.00 28,887 27,649 128,863 8.00 519.00 31,396 30,130 158,993 9.00 520.00 33,962 32,667 191,660 Culvert/Orifice Structures Weir Structures [A] [B] [C] [PrfRsr] [A] [B] [C] [D] Rise(in) = 24.00 4.00 6.00 0.00 Crest Len(ft) = 16.00 20.00 0.00 0.00 Span(in) = 24.00 4.00 48.00 0.00 Crest El.(ft) = 517.25 518.50 0.00 0.00 No.Barrels = 1 1 1 0 Weir Coeff. = 3.33 2.60 3.33 3.33 Invert El.(ft) = 511.00 515.00 516.25 0.00 Weir Type = Broad Broad --- --- Length(ft) = 110.00 0.00 0.00 0.00 Multi-Stage = Yes No No No Slope(%) = 0.50 0.00 0.00 n/a N-Value = .013 .013 .013 n/a Orifice Coeff. = 0.60 0.60 0.60 0.60 Exfil.(in/hr) = 0.000(by Wet area) Multi-Stage = n/a Yes Yes 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 Elev(ft) 10.00 521.00 8.00 519.00 6.00 517.00 4.00 515.00 2.00 513.00 0.00 511.00 0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 110.0 120.0 130.0 140.0 Total Q Discharge(cfs) 17 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 9 Bypass 1 Hydrograph type = SCS Runoff Peak discharge = 15.82 cfs Storm frequency = 2 yrs Time to peak = 730 min Time interval = 2 min Hyd. volume = 73,135 cuft Drainage area = 31.080 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.20 min Total precip. = 3.64 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Bypass 1 Q (cfs) Hyd. No. 9-- 2 Year Q (cfs) 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 ::: 3.00 - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 9 Time (min) 18 TR55 Tc Worksheet Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Hyd. No. 9 Bypass 1 Description A B C Totals Sheet Flow Manning's n-value = 0.240 0.011 0.011 Flow length (ft) = 150.0 0.0 0.0 Two-year 24-hr precip. (in) = 3.64 0.00 0.00 Land slope (%) = 2.00 0.00 0.00 Travel Time (min) = 18.51 + 0.00 + 0.00 = 18.51 Shallow Concentrated Flow Flow length (ft) = 628.00 0.00 0.00 Watercourse slope (%) = 5.70 0.00 0.00 Surface description = Unpaved Paved Paved Average velocity (ft/s) =3.85 0.00 0.00 Travel Time (min) = 2.72 + 0.00 + 0.00 = 2.72 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 0.0 Travel Time (min) = 0.00 + 0.00 + 0.00 = 0.00 Total Travel Time, Tc 21.20 min 19 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 10 POST-West Hydrograph type = Combine Peak discharge = 15.82 cfs Storm frequency = 2 yrs Time to peak = 730 min Time interval = 2 min Hyd. volume = 108,817 cuft Inflow hyds. = 8, 9 Contrib. drain. area = 31.080 ac POST-West Q (cfs) Hyd. No. 10 -- 2 Year Q (cfs) 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 3.00 3.00 0.00 R ! 0.00 0 240 480 720 960 1200 1440 1680 1920 2160 2400 2640 Time (min) Hyd No. 10 Hyd No. 8 Hyd No. 9 20 Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 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 56.81 2 728 208,713 Developed Area 2 2 Reservoir 16.53 2 752 201,850 1 517.88 94,539 Basin 2 3 SCS Runoff 93.94 2 728 341,401 Pre-West 4 SCS Runoff 25.83 2 730 103,141 Pre-East 5 SCS Runoff 9.151 2 718 18,441 Bypass 2 6 Combine 17.41 2 748 220,291 2,5 POST-East 7 SCS Runoff 81.45 2 716 165,662 Developed Area 1 8 Reservoir 5.237 2 760 110,600 7 516.75 94,946 Basin 1 9 SCS Runoff 47.66 2 728 178,303 Bypass 1 10 Combine 49.58 2 728 288,902 8,9 POST-West Hydro-22018.gpw Return Period: 10 Year Monday, 04/29/2024 21 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 1 Developed Area 2 Hydrograph type = SCS Runoff Peak discharge = 56.81 cfs Storm frequency = 10 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 208,713 cuft Drainage area = 20.310 ac Curve number = 77* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 24.80 min Total precip. = 5.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(8.690 x 98)+(11.620 x 61)]/20.310 Developed Area 2 Q (cfs) Hyd. No. 1 -- 10 Year Q (cfs) 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 - - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 1 Time (min) 22 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 2 Basin 2 Hydrograph type = Reservoir Peak discharge = 16.53 cfs Storm frequency = 10 yrs Time to peak = 752 min Time interval = 2 min Hyd. volume = 201,850 cuft Inflow hyd. No. = 1 - Developed Area 2 Max. Elevation = 517.88 ft Reservoir name = Basin 2 Max. Storage = 94,539 cuft Storage Indication method used. Basin 2 Q (cfs) Hyd. No. 2 -- 10 Year Q (cfs) 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 1 '- 0.00 0 240 480 720 960 1200 1440 1680 1920 2160 2400 Time (min) Hyd No. 2 Hyd No. 1 111111111 Total storage used = 94,539 cuft 23 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 3 Pre-West Hydrograph type = SCS Runoff Peak discharge = 93.94 cfs Storm frequency = 10 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 341,401 cuft Drainage area = 51.950 ac Curve number = 64* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.20 min Total precip. = 5.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(4.530 x 98)+(47.420 x 61)]/51.950 Pre-West Q (cfs) Hyd. No. 3 -- 10 Year Q (cfs) 100.00 100.00 90.00 90.00 80.00 80.00 70.00 70.00 60.00 60.00 50.00 - 50.00 40.00 - 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 3 Time (min) 24 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 4 Pre-East Hydrograph type = SCS Runoff Peak discharge = 25.83 cfs Storm frequency = 10 yrs Time to peak = 730 min Time interval = 2 min Hyd. volume = 103,141 cuft Drainage area = 18.590 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 26.50 min Total precip. = 5.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Pre-East Q (cfs) Hyd. No. 4 -- 10 Year Q (cfs) 28.00 28.00 24.00 i 24.00 20.00 20.00 16.00 16.00 12.00 12.00 8.00 8.00 4.00 4.00 0.00 - J 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 4 Time (min) 25 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 5 Bypass 2 Hydrograph type = SCS Runoff Peak discharge = 9.151 cfs Storm frequency = 10 yrs Time to peak = 718 min Time interval = 2 min Hyd. volume = 18,441 cuft Drainage area = 3.490 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 5.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Bypass 2 Q (cfs) Hyd. No. 5-- 10 Year Q (cfs) 10.00 - 10.00 8.00 8.00 6.00 - 6.00 4.00 - 4.00 2.00 — — 2.00 1 _ 0.00 A ,- 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 5 Time (min) 26 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 6 POST-East Hydrograph type = Combine Peak discharge = 17.41 cfs Storm frequency = 10 yrs Time to peak = 748 min Time interval = 2 min Hyd. volume = 220,291 cuft Inflow hyds. = 2, 5 Contrib. drain. area = 3.490 ac POST-East Q (cfs) Hyd. No. 6 -- 10 Year Q (cfs) 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 ,\ 3.00 3.00 0.00 - ' 0.00 0 240 480 720 960 1200 1440 1680 1920 2160 Time (min) Hyd No. 6 Hyd No. 2 Hyd No. 5 27 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 7 Developed Area 1 Hydrograph type = SCS Runoff Peak discharge = 81.45 cfs Storm frequency = 10 yrs Time to peak = 716 min Time interval = 2 min Hyd. volume = 165,662 cuft Drainage area = 15.900 ac Curve number = 79* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 5.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Composite(Area/CN)=[(7.560 x 98)+(8.340 x 61)]/15.900 Developed Area 1 Q (cfs) Hyd. No. 7 -- 10 Year Q (cfs) 90.00 90.00 —80.00 80.00 70.00 70.00 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 - ' 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 Hyd No. 7 Time (min) 28 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 8 Basin 1 Hydrograph type = Reservoir Peak discharge = 5.237 cfs Storm frequency = 10 yrs Time to peak = 760 min Time interval = 2 min Hyd. volume = 110,600 cuft Inflow hyd. No. = 7 - Developed Area 1 Max. Elevation = 516.75 ft Reservoir name = Basin 1 Max. Storage = 94,946 cuft Storage Indication method used. Basin 1 Q (cfs) Hyd. No. 8 -- 10 Year Q (cfs) 90.00 90.00 80.00 80.00 70.00 70.00 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 - 0.00 0 360 720 1080 1440 1800 2160 2520 2880 3240 3600 Time (min) Hyd No. 8 Hyd No. 7 111111111 Total storage used = 94,946 cuft 29 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 9 Bypass 1 Hydrograph type = SCS Runoff Peak discharge = 47.66 cfs Storm frequency = 10 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 178,303 cuft Drainage area = 31.080 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.20 min Total precip. = 5.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Bypass 1 Q (cfs) Hyd. No. 9-- 10 Year Q (cfs) 50.00 50.00 i_ 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 j LI 0.00 — 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 9 Time (min) 30 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 10 POST-West Hydrograph type = Combine Peak discharge = 49.58 cfs Storm frequency = 10 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 288,902 cuft Inflow hyds. = 8, 9 Contrib. drain. area = 31.080 ac POST-West Q (cfs) Hyd. No. 10 -- 10 Year Q (cfs) 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 U l 10.00 10.00 IIII 0.00 — . 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Time (min) Hyd No. 10 Hyd No. 8 Hyd No. 9 31 Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 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 74.03 2 728 271,595 Developed Area 2 2 Reservoir 17.85 2 754 264,685 1 518.38 126,085 Basin 2 3 SCS Runoff 134.15 2 728 475,966 Pre-West 4 SCS Runoff 38.17 2 730 146,728 Pre-East 5 SCS Runoff 13.11 2 718 26,234 Bypass 2 6 Combine 19.10 2 744 290,919 2,5 POST-East 7 SCS Runoff 104.17 2 716 213,662 Developed Area 1 8 Reservoir 13.03 2 734 158,595 7 517.40 112,393 Basin 1 9 SCS Runoff 70.33 2 728 253,654 I Bypass 1 10 Combine 83.05 2 728 412,248 8,9 POST-West Hydro-22018.gpw Return Period: 25 Year Monday, 04/29/2024 32 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 1 Developed Area 2 Hydrograph type = SCS Runoff Peak discharge = 74.03 cfs Storm frequency = 25 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 271,595 cuft Drainage area = 20.310 ac Curve number = 77* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 24.80 min Total precip. = 6.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(8.690 x 98)+(11.620 x 61)]/20.310 Developed Area 2 Q (cfs) Hyd. No. 1 -- 25 Year Q (cfs) 80.00 80.00 70.00 I I 70.00 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 - - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 1 Time (min) 33 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 2 Basin 2 Hydrograph type = Reservoir Peak discharge = 17.85 cfs Storm frequency = 25 yrs Time to peak = 754 min Time interval = 2 min Hyd. volume = 264,685 cuft Inflow hyd. No. = 1 - Developed Area 2 Max. Elevation = 518.38 ft Reservoir name = Basin 2 Max. Storage = 126,085 cuft Storage Indication method used. Basin 2 Q (cfs) Hyd. No. 2 -- 25 Year Q (cfs) 80.00 80.00 70.00 70.00 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 '- 0.00 0 240 480 720 960 1200 1440 1680 1920 2160 Time (min) Hyd No. 2 Hyd No. 1 111111111 Total storage used = 126,085 cuft 34 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 3 Pre-West Hydrograph type = SCS Runoff Peak discharge = 134.15 cfs Storm frequency = 25 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 475,966 cuft Drainage area = 51.950 ac Curve number = 64* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.20 min Total precip. = 6.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(4.530 x 98)+(47.420 x 61)]/51.950 Pre-West Q (cfs) Hyd. No. 3 -- 25 Year Q (cfs) 140.00 140.00 120.00 120.00 100.00 100.00 80.00 80.00 60.00 60.00 40.00 40.00 20.00 20.00 � I 0.00 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 3 Time (min) 35 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 4 Pre-East Hydrograph type = SCS Runoff Peak discharge = 38.17 cfs Storm frequency = 25 yrs Time to peak = 730 min Time interval = 2 min Hyd. volume = 146,728 cuft Drainage area = 18.590 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 26.50 min Total precip. = 6.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Pre-East Q (cfs) Hyd. No. 4 -- 25 Year Q (cfs) 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 _ , I I 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Time (min) — Hyd No. 4 36 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 5 Bypass 2 Hydrograph type = SCS Runoff Peak discharge = 13.11 cfs Storm frequency = 25 yrs Time to peak = 718 min Time interval = 2 min Hyd. volume = 26,234 cuft Drainage area = 3.490 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 6.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Bypass 2 Q (cfs) Hyd. No. 5-- 25 Year Q (cfs) 14.00 - 14.00 12.00 - 12.00 10.00 10.00 8.00 1 8.00 6.00 — — 6.00 4.00 4.00 2.00 - 2.00 0.00 - - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 5 Time (min) 37 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 6 POST-East Hydrograph type = Combine Peak discharge = 19.10 cfs Storm frequency = 25 yrs Time to peak = 744 min Time interval = 2 min Hyd. volume = 290,919 cuft Inflow hyds. = 2, 5 Contrib. drain. area = 3.490 ac POST-East Q (cfs) Hyd. No. 6 -- 25 Year Q (cfs) 21.00 21.00 18.00 18.00 15.00 15.00 12.00 12.00 9.00 9.00 6.00 6.00 3.00 3.00 0.00 - • ' 0.00 0 240 480 720 960 1200 1440 1680 1920 Time (min) Hyd No. 6 Hyd No. 2 Hyd No. 5 38 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 7 Developed Area 1 Hydrograph type = SCS Runoff Peak discharge = 104.17 cfs Storm frequency = 25 yrs Time to peak = 716 min Time interval = 2 min Hyd. volume = 213,662 cuft Drainage area = 15.900 ac Curve number = 79* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 6.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(7.560 x 98)+(8.340 x 61)]/15.900 Developed Area 1 Q (cfs) Hyd. No. 7 -- 25 Year Q (cfs) 120.00 120.00 100.00 100.00 80.00 l 80.00 60.00 60.00 40.00 40.00 20.00 20.00 0.00 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 Hyd No. 7 Time (min) 39 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 8 Basin 1 Hydrograph type = Reservoir Peak discharge = 13.03 cfs Storm frequency = 25 yrs Time to peak = 734 min Time interval = 2 min Hyd. volume = 158,595 cuft Inflow hyd. No. = 7 - Developed Area 1 Max. Elevation = 517.40 ft Reservoir name = Basin 1 Max. Storage = 112,393 cuft Storage Indication method used. Basin 1 Q (cfs) Hyd. No. 8 -- 25 Year Q (cfs) 120.00 120.00 100.00 100.00 80.00 80.00 60.00 60.00 40.00 40.00 20.00 20.00 0.00 '— — 0.00 0 240 480 720 960 1200 1440 1680 1920 2160 2400 2640 2880 Time (min) Hyd No. 8 Hyd No. 7 111111111 Total storage used = 112,393 cuft 40 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 9 Bypass 1 Hydrograph type = SCS Runoff Peak discharge = 70.33 cfs Storm frequency = 25 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 253,654 cuft Drainage area = 31.080 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.20 min Total precip. = 6.30 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Bypass 1 Q (cfs) Hyd. No. 9-- 25 Year Q (cfs) 80.00 i 80.00 70.00 70.00 60.00 60.00 50.00 50.00 40.00 40.00 1 30.00 I 30.00 20.00 20.00 10.00 10.00 ."_..........._ 0.00 - ‘ - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 9 Time (min) 41 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 10 POST-West Hydrograph type = Combine Peak discharge = 83.05 cfs Storm frequency = 25 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 412,248 cuft Inflow hyds. = 8, 9 Contrib. drain. area = 31.080 ac POST-West Q (cfs) Hyd. No. 10 --25 Year Q (cfs) 90.00 90.00 80.00 80.00 70.00 I 70.00 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 - �‘lo - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Time (min) Hyd No. 10 Hyd No. 8 Hyd No. 9 42 Hydrograph Summary Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 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 102.32 2 728 376,791 Developed Area 2 2 Reservoir 41.11 2 748 369,817 1 519.00 166,947 Basin 2 3 SCS Runoff 204.15 2 726 712,043 Pre-West 4 SCS Runoff 59.88 2 730 224,272 Pre-East 5 SCS Runoff 19.99 2 718 40,099 Bypass 2 6 Combine 42.96 2 746 409,916 2,5 POST-East 7 SCS Runoff 141.08 2 716 293,500 Developed Area 1 8 Reservoir 36.93 2 724 238,427 7 518.53 144,766 Basin 1 9 SCS Runoff 110.21 2 728 387,707 Bypass 1 10 Combine 146.46 2 726 626,135 8,9 POST-West Hydro-22018.gpw Return Period: 100 Year Monday, 04/29/2024 43 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 1 Developed Area 2 Hydrograph type = SCS Runoff Peak discharge = 102.32 cfs Storm frequency = 100 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 376,791 cuft Drainage area = 20.310 ac Curve number = 77* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 24.80 min Total precip. = 7.91 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(8.690 x 98)+(11.620 x 61)]/20.310 Developed Area 2 Q (cfs) Hyd. No. 1 -- 100 Year Q (cfs) 120.00 - - 120.00 100.00 100.00 80.00 80.00 60.00 60.00 40.00 40.00 20.00 20.00 0.00 - - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 1 Time (min) 44 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 2 Basin 2 Hydrograph type = Reservoir Peak discharge = 41 .11 cfs Storm frequency = 100 yrs Time to peak = 748 min Time interval = 2 min Hyd. volume = 369,817 cuft Inflow hyd. No. = 1 - Developed Area 2 Max. Elevation = 519.00 ft Reservoir name = Basin 2 Max. Storage = 166,947 cuft Storage Indication method used. Basin 2 Q (cfs) Hyd. No. 2 -- 100 Year Q (cfs) 120.00 - - 120.00 100.00 100.00 80.00 80.00 60.00 60.00 IId 40.00 40.00 20.00 20.00 0.00 - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 1680 Time (min) — Hyd No. 2 Hyd No. 1 TTTTTT II Total storage used = 166,947 cuft 45 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 3 Pre-West Hydrograph type = SCS Runoff Peak discharge = 204.15 cfs Storm frequency = 100 yrs Time to peak = 726 min Time interval = 2 min Hyd. volume = 712,043 cuft Drainage area = 51.950 ac Curve number = 64* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.20 min Total precip. = 7.91 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 *Composite(Area/CN)=[(4.530 x 98)+(47.420 x 61)]/51.950 Pre-West Q (cfs) Hyd. No. 3 -- 100 Year Q (cfs) 210.00 210.00 180.00 180.00 150.00 150.00 120.00 120.00 90.00 90.00 60.00 60.00 30.00 30.00 1 L 0.00 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 3 Time (min) 46 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 4 Pre-East Hydrograph type = SCS Runoff Peak discharge = 59.88 cfs Storm frequency = 100 yrs Time to peak = 730 min Time interval = 2 min Hyd. volume = 224,272 cuft Drainage area = 18.590 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 26.50 min Total precip. = 7.91 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Pre-East Q (cfs) Hyd. No. 4 -- 100 Year Q (cfs) 60.00 60.00 50.00 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 — 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 4 Time (min) 47 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 5 Bypass 2 Hydrograph type = SCS Runoff Peak discharge = 19.99 cfs Storm frequency = 100 yrs Time to peak = 718 min Time interval = 2 min Hyd. volume = 40,099 cuft Drainage area = 3.490 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 7.91 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Bypass 2 Q (cfs) Hyd. No. 5 -- 100 Year Q (cfs) 21.00 I 21.00 18.00 18.00 15.00 15.00 12.00 1 12.00 9.00 9.00 6.00 6.00 3.00 3.00 0.00 S — 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 5 Time (min) 48 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 6 POST-East Hydrograph type = Combine Peak discharge = 42.96 cfs Storm frequency = 100 yrs Time to peak = 746 min Time interval = 2 min Hyd. volume = 409,916 cuft Inflow hyds. = 2, 5 Contrib. drain. area = 3.490 ac POST-East Q (cfs) Hyd. No. 6 -- 100 Year Q (cfs) 50.00 - 50.00 40.00 40.00 30.00 30.00 20.00 20.00 10.00 10.00 0.00 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 1680 Time (min) — Hyd No. 6 Hyd No. 2 Hyd No. 5 49 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 7 Developed Area 1 Hydrograph type = SCS Runoff Peak discharge = 141.08 cfs Storm frequency = 100 yrs Time to peak = 716 min Time interval = 2 min Hyd. volume = 293,500 cuft Drainage area = 15.900 ac Curve number = 79* Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = User Time of conc. (Tc) = 5.00 min Total precip. = 7.91 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Composite(Area/CN)=[(7.560 x 98)+(8.340 x 61)]/15.900 Developed Area 1 Q (cfs) Hyd. No. 7 -- 100 Year Q (cfs) 160.00 160.00 140.00 140.00 120.00 120.00 100.00 100.00 80.00 80.00 60.00 60.00 40.00 40.00 20.00 20.00 0.00 — 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 Hyd No. 7 Time (min) 50 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 8 Basin 1 Hydrograph type = Reservoir Peak discharge = 36.93 cfs Storm frequency = 100 yrs Time to peak = 724 min Time interval = 2 min Hyd. volume = 238,427 cuft Inflow hyd. No. = 7 - Developed Area 1 Max. Elevation = 518.53 ft Reservoir name = Basin 1 Max. Storage = 144,766 cuft Storage Indication method used. Basin 1 Q (cfs) Hyd. No. 8 -- 100 Year Q (cfs) 160.00 160.00 140.00 140.00 120.00 120.00 100.00 100.00 80.00 80.00 60.00 60.00 40.00 40.00 20.00 20.00 0.00 - 0.00 0 240 480 720 960 1200 1440 1680 1920 Time (min) Hyd No. 8 Hyd No. 7 111111111 Total storage used = 144,766 cuft 51 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 9 Bypass 1 Hydrograph type = SCS Runoff Peak discharge = 110.21 cfs Storm frequency = 100 yrs Time to peak = 728 min Time interval = 2 min Hyd. volume = 387,707 cuft Drainage area = 31.080 ac Curve number = 61 Basin Slope = 0.0 % Hydraulic length = 0 ft Tc method = TR55 Time of conc. (Tc) = 21.20 min Total precip. = 7.91 in Distribution = Type II Storm duration = 24 hrs Shape factor = 484 Bypass 1 Q (cfs) Hyd. No. 9 -- 100 Year Q (cfs) 120.00 120.00 100.00 100.00 80.00 80.00 60.00 60.00 40.00 • 40.00 20.00 20.00 0.00 - — 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Hyd No. 9 Time (min) 52 Hydrograph Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Hyd. No. 10 POST-West Hydrograph type = Combine Peak discharge = 146.46 cfs Storm frequency = 100 yrs Time to peak = 726 min Time interval = 2 min Hyd. volume = 626,135 cuft Inflow hyds. = 8, 9 Contrib. drain. area = 31.080 ac POST-West Q (cfs) Hyd. No. 10 -- 100 Year Q (cfs) 160.00 160.00 140.00 1 140.00 120.00 120.00 100.00 I 100.00 80.00 80.00 I 60.00 60.00 40.00 40.00 20.00 20.00 0.00 - 0.00 0 120 240 360 480 600 720 840 960 1080 1200 1320 1440 1560 Time (min) Hyd No. 10 Hyd No. 8 Hyd No. 9 53 Hydraflow Rainfall Report Hydraflow Hydrographs Extension for Autodesk®Civil 3D®by Autodesk, Inc.v2024 Monday,04/29/2024 Return Intensity-Duration-Frequency Equation Coefficients(FHA) Period (Yrs) B D E (N/A) 1 61.0947 12.4000 0.8835 2 69.0305 12.5000 0.8674 3 0.0000 0.0000 0.0000 5 71.0689 12.4000 0.8258 10 68.8066 11.9000 0.7899 25 66.7543 11.5000 0.7522 50 55.6315 9.9000 0.6907 100 50.1117 8.9000 0.6500 File name:Albemarle.IDF Intensity= B/(Tc+ D)^E Return Intensity Values(in/hr) Period (Yrs) 5 min 10 15 20 25 30 35 40 45 50 55 60 1 4.90 3.92 3.28 2.83 2.49 2.23 2.02 1.85 1.71 1.59 1.48 1.39 2 5.76 4.64 3.89 3.37 2.98 2.67 2.42 2.22 2.05 1.91 1.79 1.68 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 5 6.72 5.45 4.62 4.02 3.57 3.22 2.94 2.70 2.51 2.34 2.20 2.07 10 7.38 6.01 5.11 4.47 3.98 3.60 3.29 3.04 2.83 2.65 2.49 2.35 25 8.10 6.64 5.68 4.98 4.46 4.05 3.72 3.44 3.21 3.01 2.84 2.69 50 8.61 7.05 6.04 5.32 4.78 4.36 4.02 3.74 3.50 3.29 3.12 2.96 100 9.06 7.42 6.37 5.63 5.07 4.64 4.29 4.00 3.75 3.54 3.36 3.20 Tc=time in minutes.Values may exceed 60. Precip.file name:T:\HYDRAFLOW\NC\Albemarle.pcp Rainfall Precipitation Table (in) Storm Distribution 1-yr 2-yr 3-yr 5-yr 10-yr 25-yr 50-yr 100-yr SCS 24-hour 1.00 3.64 0.00 4.58 5.30 6.30 7.09 7.91 SCS 6-Hr 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-1st 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-2nd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-3rd 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-4th 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Huff-Indy 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 Custom 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 ALLEN STORAGE DRAINAGE AREA MAP(S) SEE THE FULL-SIZED PLAN SHEETS (C6.1, C6.2, & C6.3)