Lead contamination in Washington, D.C., drinking water
While performing research into premature pipe corrosion for the District of Columbia Water and Sewer Authority (WASA) in 2001, Marc Edwards, an expert in plumbing corrosion, discovered lead levels in the drinking water of Washington, D.C., at least 83 times higher than the accepted safe limit. He found that the decision to change from chlorine to chloramine as a treatment chemical had caused the spike in lead levels. The contamination has left thousands of children with lifelong health risks and led to a re-evaluation of the use of monochloramine in public drinking-water systems
WASA lead service replacement notice | |
| Date | 2001 |
|---|---|
| Duration | Ongoing |
| Location | Washington, D.C., United States |
| Coordinates | 38°54′17″N 77°00′59″W |
| Type |
|
| Cause | water treatment change |
| First reporter | 2002 Washington City Paper, 2004 Washington Post |
| Outcome | 23,000 WASA customers lead service line replacement 15,000 homes in the Washington, D.C., area might still have water supplies with dangerous levels of lead |
After the Washington Post ran a series of front-page articles about Edwards's findings, resulting in widespread public concern, the United States House of Representatives conducted an investigation. The House found that the U.S. Centers for Disease Control and Prevention (CDC) had made "scientifically indefensible" claims in a report that had indicated there was no risk from the high lead levels. The Post investigation uncovered evidence of widespread misreporting of lead levels at water agencies across the United States, leading to regulatory crackdowns and changes in Environmental Protection Agency policies.
The problem was addressed in 2004 by adding additional treatments to the water, preventing the chloramine from dissolving lead in the water mains, solder joints, and plumbing fixtures.
In 2010, the CDC reported that 15,000 homes in the Washington, D.C., area might still have water supplies with dangerous levels of lead.