Answer Happy

c) An IDF relationship is given below. Answer the following questions. Find the intensity for the basin with characteristics given in Table 2. 56.42 70-242 (d + 0.138)0.53 Where i is the intensity of rainfall in mm/h, T is the return period (i.e. ARI) in years and d is the storm duration. Use an overland flow time equation as: 103n 1/3 to 51/5 1 Where t, is the overland flow time, L is the overland flow distance, and n is the Horton's surface roughness and is the average overland slope. Table 2 Characteristics Values Design return period 10 Distance of overland flow (m) 70 Distance of flow in channelised drain (m) 250 Velocity of channelised drain flow (m/s) 1.5 Horton's roughness 0.035 Average surface slope (%) 2