2.8.1. Estimation of Peak Flood Floods or flows in a stream depend upon several factors the influence of which on floods cannot be ascertained accurately. Therefore, the floods, like other hydrologic processes, cannot be modelled analytically.
The following alternative methods are used for estimation of the peak flood: (i) Rational method
(ii) Empirical method
(iii) Unit hydrograph method (iv) Flood—frequency method.
The choice of a method for estimation of the peak flood primarily depends upon the importance of the work and available data.
