Reference no: EM13343784

Question 1: The variation of (2S/dt + Q) with Q, of a basin is given by Q = 0.0015(2S/dt + Q)2 + 0.195(2S/dt + Q) - 0.3833. The outlet structure is a weir with crest length L = 1.5 m set at elevation Y = 30.5 m and discharge coefficient kw = 0.4. The storage of the basin increases linearly from 0 at Y = 30.5 m to 16,980 m3 at Y = 35 m and the initial water level is at Y = 30.9 m.

(i) Determine the peak outflow rate when the following inflow hydrograph is routed through this basin. 

(min)     0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160

Q(m3/s) 0 1.4 2.8 4.3 5.7 7.1 8.5 7.6 6.8 5.9 5.1 4.3 3.4 2.6 1.7 0.8 0

(ii) What is the design storage and water surface elevation at the peak outflow rate.