Basic Information

Corrosion is the degradation of metal. In water distribution pipelines, valves, and fixtures, it can cause the degradation of the quality our drinking water.

Corrosion—a big problem for our drinking water distribution systems—is caused by oxidation or chemical action. EPA has estimated that $138 billion will be needed over the next 20 years to maintain and replace existing drinking water systems and that $77 billion of this will be dedicated to repairing and rehabilitating pipelines. Many water distribution systems in the United States are approaching 100 years old; an estimated 26 percent of distribution system pipeline is unlined cast iron and steel and is in poor condition.

Furthermore, contamination entering our distribution systems is responsible for a significant percentage of the waterborne disease outbreaks reported in recent years. EPA’s research into corrosion and its related reactions leads to using safer materials in the production of plumbing fixtures and helps ensure that corrosion control treatments are optimized.

Corrosion by-products that form on the surface of pipes and fixtures affect the solubility of lead, copper, and iron, and ultimately their levels at the consumer’s tap. Other types of scales (hard mineral coatings) can form diffusion barriers on metal pipe surfaces, which can reduce the release of metal into distribution systems water.

In addition, corrosion by-products and other solids that accumulate in a distribution system can adsorb trace contaminants, such as arsenic. However, the contaminants are then subject to potential release back into the water, causing elevated levels at the consumer’s tap.

Darren Lytle
(513) 569-7432

Michael Schock
(513) 569-7412

Michelle Latham
(513) 569-7601

See Also:

About Drinking Water Distribution Systems

Distribution System Simulators (DSS) Research

Test and Evaluation Facility

List of Drinking Water Contaminants and MCLs