WSSC Water announced Tuesday evening that power has been fully restored to its Potomac Water Filtration Plant and the facility is operating at full production following an electrical failure earlier in the day.
According to the latest update, shared on Tuesday night, drinking water remains safe to drink and use, and there is currently no boil water advisory in effect for Montgomery or Prince George’s counties. WSSC Water also said there are no indications that the outage was caused by a cyberattack or other bad actor.
Despite the restoration, WSSC Water continues to strongly urge all 1.9 million customers in Montgomery and Prince George’s counties to use water only for essential purposes while the distribution system recovers. Customers are being asked to avoid outdoor water use, limit toilet flushing and avoid or limit the use of washing machines and dishwashers.
According to WSSC Water, commercial power has been restored to both electrical feeders serving the Potomac plant. A temporary internal workaround is currently in place, allowing the facility to operate at full production while crews continue working on permanent repairs.
Water storage throughout the system was significantly depleted during the outage and has now begun to recover. WSSC Water expects storage levels to continue refilling overnight and into Wednesday, when customer demand is typically at its lowest. The utility plans to reevaluate the system Wednesday morning to determine whether the essential-water-use-only request can be lifted.
The outage began at approximately 4:30am Tuesday when an electrical feed providing power to the plant failed. The Potomac facility normally has two electrical feeds and can operate fully using either one, but the other feed had been taken out of service in mid-September for routine Pepco maintenance intended to improve reliability and resiliency.
Pepco mobilized to restore the feed that had been undergoing maintenance, and power was restored to it at approximately noon. However, additional internal electrical issues at the plant prevented the facility from immediately restarting.
Crews were eventually able to resolve the issue and return the facility to normal operations at approximately 3:45pm. WSSC Water said the failed component on the second electrical feeder has also been identified and replaced. That feeder will return to service in coordination with Pepco once the system has stabilized. Electrical teams remain on site to monitor the temporary workaround and complete permanent repairs.
The Potomac Water Filtration Plant draws water directly from the Potomac River and is the larger of WSSC Water’s two filtration plants, supplying approximately 70% to 75% of the drinking water used by WSSC Water customers.
Although the immediate threat of a boil water advisory has passed, WSSC Water emphasized that continued conservation remains critical while storage levels recover.
