Water Conservation and Capacity Expansion

Abstract

AS water becomes relatively more scarce and as the cost of developing new sources of water increases, projects designed to reduce the quantities of water consumed (i.e, demand management projects) become more attractive alternatives to supply augmentation projects. A framework is presented that allows planners of water supply systems to make efficient use of water resources by explicitly considering the management of the demand for water as a supplement to traditional supply augmentation projects. The framework includes a dynamic programming algorithm to determine the optimal combination of supply augmentation and demand management projects. Two optimization criteria are considered: (1) Minimization of the present value of the cost of implementing the projects; and (2) minimization of the expected value of the costs to cope with emergencies in the supply of water. The tradeoffs between the two objectives are examined through the development of the set of noninferior solutions using the Non‐Inferior Set Estimation method. The applicability of the framework is illustrated in a case study involving the Santa Clara Valley Water District in Santa Clara County, California.