WASHINGTON (AP) – A do-not-drink order remains in effect for tap water in part of northwest Washington due to contamination from a petroleum product that remains in the system.

D.C. Water expanded the restriction area slightly on Thursday night, extending it east to New Jersey Avenue. More than 350 customers in the Shaw neighborhood were ordered not to drink their water after people noticed a petroleum smell Wednesday.

Three schools in the area were closed Thursday and Friday due to the water restriction. The schools are Cleveland, Garrison and Seaton elementary schools.

D.C. Water crews have been working to flush the system for a second time to remove contaminants from the water. The system was flushed early Thursday, but tests indicated the water was still contaminated.

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