PLANNING A DISTRIBUTION-SYSTEM FLUSHING PROGRAM

The main objective of flushing distribution systems is to improve water quality and service. Flushing programs preserve and improve water quality and control bacterial growth. An effective flushing program anticipates and prevents water quality problems and customer complaints. The fundamental mechanics of flushing are well defined, but little has been known about how to evaluate or optimize the effectiveness of flushing programs. More than half the utilities surveyed for this article have flushing programs and use customer complaints to locate problems in die distribution system. A spreadsheet was used to order areas within a distribution system by flushing priority on the basis of complaint data. Each area could be flushed in anticipation of the peak of complaints. A general planning method or protocol was developed to assist with program organization and analysis. A review of a flushing program conducted by the Philadelphia Suburban Water Company is included.