Answer Happy

Q4. (a) Figure Q4 shows two catchments, A and B that are being facilitated by a drainage system which consist of two inlets and two pipes. Catchment A has an area of 1 ha and is 50% impervious; catchment B has an area of 2 ha and is 10% impervious. The runoff coefficient, C; length of overland flow, L; average flow velocity, V; are given in Table Q4. Calculate the peak flow to be handled the both pipes based on 10-years IDF equation, In(i) = a + b ln(t) + c (ln(t))² + d (In(t))", where a, b, c, and d are 4.490, 0.997,-0.328 and 0.021, respectively. Table Q4a: Characteristics of the catchment Catchment A B Surface pervious impervious pervious impervious C 0.2 0.9 0.2 0.9 L (m) 80 60 140 65 V (m/s) 0.029 0.091 0.033 0.090