If the peak discharge of a storm water drain (S.W. Drain) is expected to exceed 150 cumecs, the free board to be provided, is_________________?

Skimming tanks are__________________?

The formula which accepts the value of rugosity coefficient n = 0.012 to be used in Manning’s formula, is given by______________________?

The sewer which resists sulphide corrosion, is____________________?

The rainfall at any place may be determined by__________________?