The Environmental Protection Agency (EPA) estimates that the nation must invest $390 billion over the next 20 years to replace existing systems and build new ones to meet the increasing demands of chemical and microbial contaminants entering distribution systems. As part of the EPA’s effort to promote an increased supply of safe drinking water, the agency has established the Drinking Water Distribution Systems Corrosion Research Program. The program has helped the EPA to develop an enhanced understanding of the corrosion of distribution systems and its related reactions so that clean, fresh drinking water can be delivered to the public consistently.
The EPA’s drinking water studies are based on the multi-barrier concept that consists of selecting the best available water source and protecting it from contamination, as well as preventing water quality deterioration in distribution systems. In addition to the corrosion research program, the EPA has also established the Environmental Technology Verification Program, which develops testing protocols and verifies the performance of innovative technologies that have the potential to improve the protection of the public’s drinking water. More information on these programs and others can be found on the EPA’s website.
To quantify the impact of distribution systems on drinking water quality and to begin to diagnose potential issues, Michele Prévost, PhD, a specialist in water treatment and distribution, suggested field investigations of low and negative pressure to monitor the water quality in the system, investigate the relationship between positive coliform samples and distribution system operations, document specific contamination sources and events, and monitor actual intrusion at the worst potential sites. Dr. Prévost is a professor in the department of civil, geological, and mining engineering at Polytechnique Montréal in Québec.