A boil water advisory was issued Wednesday night for the entire District of Columbia and neighboring Arlington County due to an increase in algae blooms in the Potomac River, officials said.
The District of Columbia Water and Sewer Authority said the warning, which it called “precautionary,” also included the Pentagon, Arlington National Cemetery and Reagan National Airport.
“We have no information that the water is contaminated from this incident, but we are issuing this warning as a precaution while we test the water,” the agency said.
The Washington Aqueduct originates from the Potomac River and serves as a public water supply for nearly one million people in the DC area, Arlington County and other parts of Northern Virginia.
The U.S. Army Corps of Engineers said in a news release that the advisory stemmed from “elevated levels of turbidity in the water supply caused by increased algal blooms on the Potomac River.”
Turbidity is a measure of water clarity and cloudiness.
“Customers may notice that their water appears cloudy or cloudy,” Arlington County said in a news release.
The Washington Aqueduct has two water treatment plants. The Army Corps of Engineers responded to the high turbidity by temporarily transferring all water treatment operations from the Dalecarlia plant to the McMillan plant, DC Water said.
The Environmental Protection Agency also authorized the addition of additional copper sulfate and sodium permanganate to the aqueduct tanks to combat algae, the Army Corps of Engineers said.
Residents were advised to bring drinking water to a boil for one minute before allowing it to cool. Water should be stored in a covered container.
The advisory will remain in effect until further testing finds the water safe to drink.
