A supply based reliability measure for water distribution systems

The purpose of a water distribution system is to supply user's demands with adequate pressure head under a range of demand and system conditions. From a consumer's perspective, meeting demand and pressure head requirements are the measures of acceptability. A nonlinear optimization problem can be posed to determine the supply at each node which can be withdrawn while maintaining adequate pressure for a given system. A measure, either a simple ratio or a more complex entropy term, can then be used to define the reliability-availability of the system. This paper will present an application of these concepts to determine the reliability of an existing system and present a formulation for extending the term to include time dependency and incorporating it in an optimal design procedure. (Authors)