An Optimization Model for a Water Distribution Network Design

Description

A Water distribution system connects consumers to sources of water, using hydraulic components, such as pipes, valves, and reservoirs. The engineer faced with the design of such a system, or of additions to an existing system, has to select the sizes of its components. Also he has to consider the way in which the operational components, pumps and valves, will be used to supply the required demands with adequate pressures. The network has to perform adequately under varying demand loads, hydraulic and operational conditions. Operational decisions for these loads are essentially part of the design process, since one cannot separate the so-called design decisions, i.e. the sizing of components, from the operational decisions; they are two inseparable parts of one problem. This work has therefore presented a method for optimizing the design of a water distribution network system using pipe diameter as decision variable under the required demand loading and hydraulic conditions. It has been established that increasing the minimum pressure will lead to the reduction in the required pipe diameter which will in turn reduce the cost of installation. The modelling approach developed can be used by engineers and planners to obtain economical pipe sizes for a network designed to serve newly planned layouts.