WSSC Water has lifted its essential-water-use-only request for residents in Montgomery and Prince George’s counties, according to an update from the utility company on Wednesday evening. 

For nearly two days, the water utility had requested its customers to only use water for essential purposes due to a power outage that occurred Tuesday morning at its filtration plant in Potomac. Though power to the plant was restored on Tuesday, the utility still experienced internal electrical issues at the plant that interrupted water production. 

“WSSC Water’s Potomac Water Filtration Plant continues to produce water to meet customer demand,” the utility said Wednesday evening. “The water distribution system is replenished to normal levels and power delivery to the plant remains stable and adequate.” 

During a virtual media briefing Wednesday afternoon with Montgomery County Executive Marc Elrich (D), WSSC General Manager and CEO Kishia Powell said one of the two electrical feeds at the Potomac plant was offline for scheduled maintenance early Tuesday when the facility experienced what she called a “power blip” from the other feed. 

“Fortunately, because we do planning and emergency preparedness before we undertake these operations, the system was full,” Powell said.  

Those preparedness measures, combined with WSSC customers heeding the utility’s warnings about limiting their water use, helped buy time for electrical workers to route around “what may be the troubled area,” Powell added. 

The plant is operating with a “temporary electrical configuration” as crews work to determine the source of the power issue and implement a permanent solution, according to WSSC. The temporary configuration is “stable and adequate,” WSSC said in a Wednesday evening news release. 

“WSSC Water appreciates the cooperation, partnership, and patience of customers,” the utility said in the release. “Their efforts to limit water use helped preserve water in the system, avoid a potential Boil Water Advisory and ensure adequate fire protection across both counties.” 

The essential water use advisory was in effect for the regional water utility’s 1.9 million customers across Montgomery and Prince George’s counties. Customers of WSSC also include residents in Takoma Park and Gaithersburg. 

On Tuesday morning, WSSC Water issued an advisory that its Potomac Water Filtration Plant was experiencing a power outage and urged customers to use water only for essential purposes. The plant supplies drinking water to roughly 75% of WSSC’s customers – nearly 1.43 million people. 

In a statement Tuesday to Bethesda Today, Pepco said the company had determined that after restoring power to the plant, the issue was due to WSSC equipment. 

There was a risk of a boil water advisory on Tuesday; however, that did not occur.  

On Wednesday morning, WSSC said in an update that crews had made progress overnight and the situation had “stabilized from a water production standpoint.” Throughout the day, critical electrical work at the plant was still ongoing. 

Pepco helped to restored the electrical feed that had been out of service for maintenance, with restoration at approximately noon on Tuesday. 

“While the external power feed was restored, internal electrical issues inside the plant prevented the facility from restarting. Crews at the plant conducted a heroic effort to solve the problem and restored power to the facility at approximately 3:45 p.m. yesterday,” WSSC Water said Wednesday evening. 

According to WSSC, the Potomac filtration plant draws water from the Potomac River and is the utility’s largest water filtration plant. The plant treats and supplies drinking water to up to 75% of WSSC Water customers. 

WSSC Water’s other water filtration plant, on the Patuxent River, cannot produce enough drinking water to meet the daily demand for roughly 170 million gallons of water, according to WSSC. The Patuxent plant provides roughly 90 to 95 million gallons per day. 

According to a social media post by the City of Rockville on Tuesday, the city’s water supply was not affected by the issues at WSSC’s plant. The city said that it provides water and sewage to 70% of its roughly 13,000 customers and the remainder are served through WSSC. 

Bethesda Today reporters Ceoli Jacoby and Ashlyn Campbell contributed to this article.