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A boil-water advisory is out for nearly half of all Prince George's County residents after a massive water main break that shut down a portion of the Beltway.
The 54-inch main break pumped millions of gallons of water onto the Capital Beltway Monday morning before crews were able to close the water valves.
Officials say the break caused a loss of pressure in the county's water system and that could have allowed contamination. As a result, the Washington Suburban Sanitary Commission is issuing a boil-water order for nearly 500,000 customers.
They're advising people to boil water that's used for drinking, washing dishes, brushing teeth and food preparation -- also water used by pets.
Officials say they'll lift the ban when they can confirm water quality tests.