Know the steps that can be taken to reduce the negative impact of corrosion on water system piping.

Corrosion is a process that attacks buried metallic water distribution and transmission piping often resulting in unexplained water loss, service disruptions, and increased maintenance and operating costs. A recent study indicated the annual cost of corrosion of water systems in the United States alone exceeds $22 billion and is expected to grow. The goal of this material is to identify the corrosion process and proven measures that can be employed to reduce corrosion's negative impact on metallic piping and associated fittings. Eliminating or reducing corrosion will not only help conserve water, but also reduce leaks and extend the life of water piping systems. Topics to be reviewed and discussed will include stray electrical currents, aggressive soils, bimetallic coupling, coatings, cathodic protection, corrosion coupons and polyethylene encasement. Several municipal case histories will also be discussed.