Estimation of extreme low flows for pumped storage reservoir design

Abstract

A method for estimating the probability of nonexceedance of low flows for a reservoir fed directly by one river with additional pumped inflow from a second river is described, The method is based on the joint probability distribution of an extreme value distribution and a truncated extreme value distribution. The estimates of the probabilities of given low flows are given by integrals. These are evaluated numerically for a range of low flows and maximum daily pumping rates. Details are given for the particular case of total inflow during a period of three consecutive months, but the method could be used for any duration.