Oil Sheen Being Monitored on Potomac River

McLEAN, VA -- An oily-looking sheen of unknown origin is making its way down the Potomac River. The sheen was reported by state and local officials Sunday and is being monitored as it heads downriver from the Sterling area, according to the Metropolitan Washington Council of Governments (MWCG).

A spokeswoman Tuesday said authorities have not yet identified the substance.

Officials are monitoring water quality and the time it takes the oily plume to reach drinking water intakes, MWCG said in a news release Tuesday. Authorities are evaluating any potential changes to downstream water quality and are making preparations to protect the region’s drinking water.

Water systems involved with the response include Fairfax Water, which provides water to 2 million customers in the Northern Virginia communities of Fairfax, Falls Church, Loudoun, Prince William and Alexandria depend on Fairfax Water for drinking water.

Fairfax Water, in an announcement about the sheen, said:

• There is no need for Fairfax Water customers to take any action or precautions at this time.
• Fairfax Water is using its submerged off‐shore intake which avoids the withdrawal of potentially contaminated surface water into the Corbalis water‐ treatment plant. We are also treating the water with activated carbon as precautionary measure.
• Fairfax Water is conducting ongoing water sampling and analysis to monitor water quality.

Others monitoring the sheen include Frederick County, the Town of Leesburg, the City of Rockville, the Washington Aqueduct and the Washington Suburban Sanitary Commission.

Officials believe the event is unlikely to disrupt water supplies in the metropolitan Washington region, MWCG said. Actions to protect the region's drinking water include increasing water quality testing in the river, closing and alternating intakes, adding activated carbon to boost drinking water treatment, and placing protective booms around intakes. Water systems and jurisdictions will provide updates about the response and notify residents if additional actions are needed. Customers can contact their drinking water provider or check the COG website for additional information.

The U.S. Environmental Protection Agency Region 3 is the lead response agency. Actions to protect the regional water supply and public health are being coordinated and implemented by water systems on the Potomac River, working closely with the U.S. EPA, Maryland Department of Environment (MDE), Virginia Department of Environmental Quality (VDEQ) & Department of Health (VDH), District Department of Energy and the Environment, Interstate Commission on the Potomac River Basin, COG, and the U.S. Coast Guard.

PHOTO: DC Department of Energy and Environment