Given the inlet in Figure with h = 0.5 ft and W = 1.5 ft, determine what minimum length, L...

Given the inlet in Figure with h = 0.5 ft and W = 1.5 ft, determine what minimum length, L, of inlet (in whole-foot increments) is required for Q = 6 cfs, such that the depth of flow at the curb does not exceed 0.5 ft.

Figure

Standard curb inlet with gutter depression at a sag in a roadway.