Ditch Calculations

SUGAR CREEK GREENWAY
MEK-20000

5. DRAINAGE DITCH CALCULATIONS

DITCH HYDROLOGY
Maximum Area
[Date]
I. SCS CURVE NUMBERS
HSG Right of Way Commercial Industrial Residential (1 acre)Open Space
A 98 89 81 51 39
B 98 92 88 68 61
C 98 94 91 79 74
D 98 95 93 84 80
Assume:HSG 'A' =0.0%
HSG 'B' =0.0%
HSG 'C' =0.0%
HSG 'D' =100.0%
Cover Condition SCS CN
Right of Way 98
Commercial 95
Industrial 93
Residential 84
Open Space 80
II. POST-DEVELOPMENT
Watershed Land Use Breakdown
Contributing Area SCS CN Area [sf]Area [acres]
Right of Way 98 0 0.00
Commercial 95 0 0.00
Industrial 93 0 0.00
Residential 84 150,000 3.44
Open Space 80 0 0.00
Total area =3.44 acres Largest Ditch Area
150,000 sf
Composite SCS CN =84
% Impervious =0.0%
C. Time of Concentration Information (Kirpich Equation)
Longest Hydraulic Flow Length (ft) =700
Surface slope (ft/ft) =0.05
Time of Concentration (min) =5
Comments
-
-
Assume good condition
Assume 1 acre
Assume good condition
-
Assume 1 acre
Comments
-
-
-
Subsection: Master Network Summary
Catchments Summary
Peak Flow
(ft³/s)
Time to Peak
(min)
Hydrograph
Volume
(ac-ft)
Return
Event
(years)
ScenarioLabel
7.35198.00.22510Post 10-YearSUB 1
Node Summary
Peak Flow
(ft³/s)
Time to Peak
(min)
Hydrograph
Volume
(ac-ft)
Return
Event
(years)
ScenarioLabel
7.35198.00.22510Post 10-YearPOI
7/1/2022Ditch.ppc
Bokar Diaby,EIAiken SCETV
Max Flow Ditch Calculation
Project Description
Manning
FormulaFriction Method
Normal DepthSolve For
Input Data
0.030Roughness Coefficient
ft/ft0.010Channel Slope
H:V3.000Left Side Slope
H:V3.000Right Side Slope
cfs7.35Discharge
Results
in11.2Normal Depth
ft²2.6Flow Area
ft5.9Wetted Perimeter
in5.3Hydraulic Radius
ft5.58Top Width
in9.9Critical Depth
ft/ft0.019Critical Slope
ft/s2.83Velocity
ft0.12Velocity Head
ft1.06Specific Energy
0.731Froude Number
SubcriticalFlow Type
GVF Input Data
in0.0Downstream Depth
ft0.0Length
0Number Of Steps
GVF Output Data
in0.0Upstream Depth
N/AProfile Description
ft0.00Profile Headloss
ft/s0.00Downstream Velocity
ft/s0.00Upstream Velocity
in11.2Normal Depth
in9.9Critical Depth
ft/ft0.010Channel Slope
ft/ft0.019Critical Slope
Page 1 of 127 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA [phone]
7/1/2022
FlowMaster
[10.03.00.03]
Bentley Systems, Inc. Haestad Methods Solution
CenterDitch Flow Master.fm8