Evaluation Method of Water Supply and Water Demand Potential

Abstract

Use of a river water is controlled by the lowest discharge which gives a stable water supply through a year at least, because a river discharge unstably fluctuates depending on the water balance of the basin.To expand a use of a river water, therefore, it is necessary to regulate a fluctuation of a river discharge and to increase the lowest discharge by a storage capacity such as a dam.In this paper, the evaluation theory of the relation between the lowest discharge (Q) and a storage capacity in a river basin (V), which is named as “the critical water balance method”, is newly proposed.
The relation between Q and V is investigated, and then it is confirmed to be represented by a parabolic curve.And also by using coefficients of the parabolic curve, it is clear to be able to evaluate a watersupplying capacity from a river basin and a potential water demand for a basin. The Q-V relation from this method will play an important role to discuss a comparative analysis between river basins, and an evaluation of natural and artificial storage capacity in a same dimension, an appropriate use and development of water resources in a river basin.