Instrumentation of Water Distribution Systems

Much of the day‐to‐day operation of a large water distribution system is performed from a central location. Instrumentation allows operators in the control center to monitor flow rates, pressures, levels, and other important information from all parts of the distribution network. In many modern utilities, instrument readings are fed to one or more computers, which evaluate distribution system needs and adjust controls as necessary. Most systems continue to maintain simpler, on‐site instrumentation at remote sites, for testing purposes and as a backup to the main system. Some small utilities depend on similar direct‐acting equipment for daily operations. This article discusses the components and functions of instruments commonly used in a modern distribution system. Control equipment, which is used to operate pumps and valves automatically or from a remote location, is not covered. This is part one of a two‐part article on instrumentation and is adapted from the AWWA publication, Introduction to Water Distribution, Module 9, Instrumentation and Control. Part two appears in the May 1985 issue of OpFlow.