Answer Happy

15.1.5 Determine the pipe diameters for the storm sewer system for the Calder Alley watershed in Prob. 15.1.1 using the rational method and the intensity-duration- frequency relationship in Prob. 15.1.4. Use the FAA method to determine time of concentration. Manning's n is 0.014. Consider a minimum cover depth of 6.0 ft. The length, slope, and ground elevation are given below: 2-1 Pipe Length (ft) 6-5 5-4 4-3 3-2 1732 1400 1480 1440 906 6 5 4 3 2 1 Inlet Ground Elevation (ft) 1183 1157 1141 1118.5 1089 E D₂ G 10000 Scale FIGURE 15.P.1 6 () 2000 f C₂ C₁ O 3 1060 B₂ B₁ Legend Manhole 2
TABLE 15.P.1 Data for Calder Alley Basin Area Sub- Principal land use area (acres) A Detached 12.1 B₁ 14.0 8.0 17.9 6.1 19.0 4.9 47.6 52.6 45.0 227.2 Small business Multifamily residential Commercial Commercial Commercial Commercial Residential and small business Residential and small business Residential G and small business Total Source: Kibler, 1982. B2 multifamily residential C₂ F Impervious Impervious percent acres 4 0.5 45 6.3 77 6.2 75 13.4 100 6.1 95 18.1 100 4.9 40 19.0 20 10.5 32 14.4 99.4 Average surface slope (%) 3.3 4.5 1.2 3.4 1.5 3.4 1.5 3.5 3.0 3.5 Runoff coefficient с 0.33 0.66 0.70 0.82 0.95 0.90 0.95 0.60 0.42 0.52 0.59 Inlet number 2 5 5 Distance to inlet 800 850 900 1300 1600 1800 1600
15.1.5 for pipe 6-5, 5-4, and 4-3