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The nation's capital is waking up on this Fourth of July to word that their water might not be safe to drink. Officials are telling everyone in D.C, including countless visitors, to boil their tap water. NPR's Adam Bearne reports.
ADAM BEARNE, BYLINE: The boil-water advisory came just hours before hundreds of thousands of visitors were expected to head into D.C. for the music and fireworks that celebrate Independence Day. Add them to the city's nearly 700,000 residents, and you've got a huge number of people without easy access to clean drinking water.
JOHN LISLE: It's terrible timing since it's the Fourth of July, and, obviously, folks plan to be celebrating.
BEARNE: That's John Lisle with DC Water. He says those plans shouldn't include using filtered water from the fridge or ice made after 9:00 p.m. on Wednesday.
LISLE: We tell our customers that home filtering devices don't take the place of boiled or bottled water, so we still recommend that they boil it.
BEARNE: The problem's being caused by an increase in algae blooms on the Potomac River. It's making the water at the Washington Aqueduct, which supplies the city's drinking water, cloudier than normal. That, in turn, makes the water treatment process less effective. Lisle says it's not clear how long the problem will last.
LISLE: It depends on the conditions on the river. And that depends a lot on how much rainfall we get and then the aqueduct's ability to manage this issue and get back to a normal supply of drinking water that they provide for us. And I think, at this point, it's too early to say how long it's going to be.
BEARNE: That's something DC Water isn't used to facing.
LISLE: When we issue boil-water advisories, it's usually because we've lost pressure in the system. And once that pressure's restored, you do a couple rounds of tests. It takes a couple days. And if both of those rounds of tests are clear, then you can lift it. We're not in that type of situation here.
BEARNE: It's not just D.C. that's affected. The alert extends to the neighboring county of Arlington, Va., which also gets its water from the Washington Aqueduct, along with the Pentagon and Reagan National Airport.
LISLE: A lot of businesses, restaurants, hospitals, etc., are going to be impacted by this. There's no doubt there is some impact, and people are going to have to modify or sort of adjust to that.
BEARNE: Lisle can't say how the issue might affect Independence Day celebrations on the National Mall. NPR has asked the National Park Service about their plans but hasn't heard back.
Adam Bearne, NPR News, Washington.
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