TUESDAY EVENING UPDATE: WSSC Continues to Monitor Plume of a Substance in the Potomac River

Substance Remains Upriver, Potomac Plant Not Affected

| News Release



LAUREL, MD – November 29, 2016: WSSC and a number of regional agencies continue to monitor a sheen of lubricant-like substance that is floating in the Potomac River. The U.S. Environmental Protection Agency is taking the lead in investigating the source of the plume, as well as coordinating a regional response to the incident.
While early river flow models estimated that the plume would reach WSSC’s Potomac Water Filtration Plant intake at some point earlier today, the substance still remains several miles upriver. At this time, WSSC continues to meet customer demand, and has not experienced any adverse impact to its drinking water quality and the plant continues to operate at full capacity.
WSSC has taken the following steps to protect its source water in the event the substance moves down river:

  • WSSC continues to maintain our system at full capacity.
  • Crews placed a boom in the river to divert any floating substance away from the intake.
  • All maintenance activities that require flushing of pipes has been halted.
  • An enhanced monitoring plan is in place at the plant, including hourly tests of the water in the river near the intake and adding additional testing of the water as it comes into the plant and before water goes out into the distribution system.

The Potomac Water Filtration Plant produces approximately 70 percent of WSSC’s treated water each day for customers across Montgomery and Prince George’s counties. The Patuxent Water Filtration Plant supplies the remainder to WSSC’s customers.


For 100 years, WSSC has proudly served the citizens of Prince George’s and Montgomery counties – providing drinking water that has always met strict Safe Drinking Water Act standards and protecting the environment through vital water resource recovery services. Our vision is to be THE world-class water utility, where excellent products and services are always on tap.


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