Study warns of potentially corrosive groundwater in watershed states

Untreated groundwater across the Chesapeake Bay watershed has a high potential of being corrosive, according to a recent study from the U.S. Geological Survey. Left untreated, corrosive groundwater could leach lead and other metals from pipes and plumbing fixtures, potentially contaminating private drinking water supplies.

Public water supplies across the country are regulated by the U.S. Environmental Protection Agency (EPA). But private water supplies must be tested and maintained by homeowners. Approximately 44 million people in the U.S. get their drinking water from private wells—including 1.7 million in Virginia and 3 million in Pennsylvania. The study, which assessed 20,000 wells across the country from 1991 to 2015, shows groundwater in Maryland, Delaware and the District of Columbia has a ‘very high’ risk of being corrosive, while groundwater in Pennsylvania, New York, Virginia and West Virginia has a ‘high’ risk.

“This study is a good reminder that prudent, routine testing of the water, including its interaction with the water supply system, is an essential first step so homeowners and their families can confidently drink water from their faucets,” said Stephen Moulton II, assistant chief of operations for the USGS National Water-Quality Assessment Program, in a release.

Corrosive water is not dangerous to drink on its own, and potentially corrosive groundwater does not indicate the presence of lead or other metals in tap water. But corrosive water may react with pipes and other plumbing fixtures, leaching metals such as lead or copper into the water and potentially cause health-related problems. Signs of leaching caused by corrosive water may include bluish-green stains, small leaks in plumbing fixtures or a metallic taste to the water.

The report, “Assessing the Potential Corrosivity of U.S. Groundwater,” can be found online.