HomeMy WebLinkAboutSW6230806_Design Calculations_20240131 (2) Permanent Diversion Swale Design Date
Dec.,2023
r Project Name Project No.
By
Brookwood Subdivision-Phase 4 TSB-18.01
-� Location TDB
Moore County,North Carolina Checked By
PAP
Rainfall Intensity(in/hr) Storm Design Used
2 year 10 year 25 year 100 year EIMIE 8.83
6.28 8.00 8.83 9.91
*based on 5 min.ToC
Calculating Run-off Coefficients('C')
Surface Type Percentages
Swale Unimp. Asphalt Concrete Brick Roof Roof Sandy Soils Heavy Soils Wooded
Areas Area Area Area inclined Flat <2% 2-7% >7% <2% 2-7% >7% Areas
Values 0.35 0.95 0.95 0.85 1.00 0.90 0.10 0.15 0.20 0.15 0.20 0.30 0.15
EXAMPLE 40% 15% MT 33% M MI 12%
PH4-SW-11 11.1. 40% 27% 33%
PH4-SW-12 20% 20% 60%
PH4-SW-13 10% 80% 10%
PH4-SW-14 40% 27% 33%
PH4-SW-15 15% 70% 15%
PH4-SW-16 50% 40% 10%
PH4-SW-17 10% 80% 10%
Design Check
Drain. Drain. Calculated Use Q n Side Depth Bottom Design/ Channel
Swale Area Area Cc Cc (cfs) Slope Width Trial cfs Slope
EXAMPLE 43,560 sf 1.00 ac. 0.57 0.57 5.06 0.030 3:1 0.78 ft 0.00 ft Increase 1.00%
PH4-SW-11 7,412 sf 0.17 ac. 0.49 0.49 0.73 _ 0.030 3:1 0.32 ft 0.00 ft OK 3.39%
PH4-SW-12 33,625 sf 0.77 ac. 0.34 0.34 2.32 _ 0.030 3:1 0.48 ft 0.00 ft OK 3.39%
PH4-SW-13 58,027 sf 1.33 ac. 0.24 0.30 3.53 0.030 3:1 0.61 ft 0.00 ft OK 2.22%
PH4-SW-14 65,812 sf 1.51 ac. 0.49 0.49 6.49 0.030 3:1 0.64 ft 0.00 ft OK 5.59%
PH4-SW-15 186,035 sf 4.27 ac. 0.28 0.30 11.31 0.030 3:1 0.96 ft 0.00 ft OK 2.00%
PH4-SW-16 105,849 sf 2.43 ac. 0.56 0.56 11.91 0.030 3:1 0.90 ft 0.00 ft OK 3.19%
PH4-SW-17 24,673 sf 0.57 ac. 0.24 0.30 1.50 0.030 3:1 0.51 ft 0.00 ft OK 1.00%
Calculating Swale Size I- Lining Types
X-section Wetted Hydraulic Trial Trial Top Width Shear Calculated Straw Straw w/Tack Coat
Area of Perimeter Radius Discharge Velocity of Channel Stress Lining S75 Straw S75 Straw with Net
Swale Flow(sf) Flow(ft) (ft) (cfs) (fps) (ft) (Ib/sf) Type P300 P300 Polypropylene
EXAMPLE 1.83 sf 4.93 ft 0.37 ft 4.67 cfs 2.56 ft/sec 4.68 ft 0.49 lb/sf S75 Straw P550 P500 Polypropylene
PH4-SW-11 0.31 sf 2.02 ft 0.15 ft 0.80 cfs 2.60 ft/sec 1.92 ft 0.68 lb/sf S75 Straw Riprap A Class A Riprap
PH4-SW-12 0.69 sf 3.04 ft 0.23 ft 2.36 cfs 3.41 ft/sec 2.88 ft 1.02 lb/sf S75 Straw Riprap B Class B Riprap
PH4-SW-13 1.12 sf 3.86 ft 0.29 ft 3.61 cfs 3.24 ft/sec 3.66 ft 0.85 lb/sf S75 Straw Riprap 1 Class 1 Riprap
PH4-SW-14 1.23 sf 4.05 ft 0.30 ft 6.52 cfs 5.30 ft/sec 3.84 ft 2.23 lb/sf RR-A or P300
PH4-SW-15 2.76 sf 6.07 ft 0.46 ft 11.49 cfs 4.16 ft/sec 5.76 ft 1.20 lb/sf S75 Straw
PH4-SW-16 2.43 sf 5.69 ft 0.43 ft 12.22 cfs 5.03 ft/sec 5.40 ft 1.79 lb/sf RR-A or P300
PH4-SW-17 0.78 sf 3.23 ft 0.24 ft 1.50 cfs 1.93 ft/sec 3.06 ft 0.32 lb/sf S75 Straw
Construction Schedule
Minimum Bottom Side Top Channel Channel
Depth Width Slope Width Slope Lining
Swale (ft) (ft) (ft)
PH4-SW-11 0.33 ft 0.00 ft 3:1 1.98 ft 3.39% S75 Straw
PH4-SW-12 0.50 ft 0.00 ft 3:1 3.00 ft 3.39% S75 Straw
PH4-SW-13 0.58 ft 0.00 ft 3:1 3.48 ft 2.22% S75 Straw
PH4-SW-14 0.58 ft 0.00 ft 3:1 3.48 ft 5.59% RR-A or P300
PH4-SW-15 1.00 ft 0.00 ft 3:1 6.00 ft 2.00% S75 Straw
PH4-SW-16 1.00 ft 0.00 ft 3:1 6.00 ft 3.19% RR-A or P300
PH4-SW-17 0.58 ft 0.00 ft 3:1 3.48 ft 1.00% S75 Straw
Intensity information tab should be updated per local requirements,current setting is from NOAA website for the project area.
indicates example user inputted data,do not delete.
indicates user provided data,all else is calculated.