Hydraulic Engineering, College of Engineering, Guindy, Madras.
The instantaneous unit hydrograph concept is explained. The basin system is assumed linear. The rainfall excess is treated as a series of impulses. Surface run-off and instantaneous unit hydrograph are treated as sampled data. Using Z-transform, a method is developed for the derivation oj instantaneous unit hydrograph ordinates. The possible difficulties that may be met with in the application of the method to actual storms are also stated.
