Boil water advisories for Washington, DC, and Arlington County, Virginia, have been lifted

CNN — Precautionary boil water advisories for Washington, DC, and Arlington County were lifted Thursday morning, after local authorities announced water quality never deviated from safety standards.

The advisory was issued Wednesday by the District of Columbia Water and Sewer Authority and Arlington County due to an increase in algae blooms in the Potomac River, as the nation’s capital prepared for its annual Fourth of July celebrations.

Affected areas included Washington, DC, Arlington County, the Pentagon, Arlington National Cemetery and Reagan National Airport.

Residents – who were told to consume only boiled or bottled water under the advisory – can now use tap water for all purposes “after it was confirmed that drinking water provided by the Washington Aqueduct never deviated from U.S. EPA established water quality standards as had been anticipated,” DC Water said.

The warnings were lifted as the area readied for an influx of visitors for the Fourth of July, including the annual fireworks display on the National Mall.

The Army Corps of Engineers said the advisory was prompted by elevated cloudiness in the water supply caused by increases in algae blooms in the Potomac River.

“Upon observing the increase in algae and resulting turbidity today, Washington Aqueduct staff implemented additional mechanical and chemical treatment solutions to help meet system water supply demands and (Environmental Protection Agency) standards,” the Army Corps said in a statement.

Turbidity is a measure of cloudiness in water the EPA says can be used to assess water quality and filtration effectiveness to indicate whether disease-causing organisms could be present.

Turbidity can indicate the presence of organisms including bacteria, viruses and parasites that can cause nausea, cramps, diarrhea and headaches. Infants, young children, older adults and people with compromised immune systems may be at greater risk, DC Water said.

Atlanta was under a state of emergency last month, after disruptions to its water service left a large swath of the city under boil-water advisories. Some summer school programs and hospital operations in the area were paused as a result. Atlanta officials cited aging pipes and crumbling infrastructure when addressing the issue.

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