Question

The following four hydrological features have to be estimated or taken as inputs before one can compute the flood hydrograph at any catchment outlet:

The correct order in which they have to be employed in the computations is

• A. 1, 2, 3, 4
• B. 2, 1, 4, 3
• C. 2, 3, 1, 4
• D. 4, 1, 3, 2

Answer 1

The correct option is C 2, 3, 1, 4

First determine the rainfall hydrograph and then infiltration index. The effective rainfall can be determined from the rainfall hydrograph and infiltration index. Now multiply the ordinates of unit hydrograph by effective rainfall. This will give direct runoff hydrograph (DRH). Finally add base flow to the DRH and flood hydrograph can be obtained.