Millions of Houston residents are expected to remain under a boil water notice until Tuesday. At least four area school districts are closed Monday in response.

After a power outage at the East Water Purification Plant on Sunday, the nation’s fourth largest city told water customers to boil water for at least two minutes before food preparation, drinking, bathing or brushing teeth. Customers were also told avoid using water from refrigerators or ice makers. Those who cannot boil water are advised to use bottled water. According toย Houston Public Works, its water system serves 2.2 million customers.

All Houston school district campuses, offices and facilitiesย are closed due to the notice. The nearbyย Aldine,ย Pasadenaย andย Spring Branchย school districts also canceled Monday classes, the Houston Chronicleย reported.

The boil water notice is expected to be lifted Tuesday morning, after the Texas Commission on Environmental Quality reviews the city’s water samples, according to Houston Public Works spokesperson Erin Jones. Workers were expected toย begin collecting samples Mondayย after the TCEQ approved the city’s water sampling plan.

During the power outage at 10:30 a.m. Sunday, water pressure at the plant brieflyย dropped below required minimum levels. Water pressure in the entire system is currently back above minimum levels for safety, Jones said Sunday.

Low pressure hurts water quality and can be a threat to public health. A reduction or loss of pressure in a water distribution system can result in backflow, when water flows in the wrong direction, allowing contaminants to enter drinking water.

Houston Mayor Sylvester Turner’s officeย tweetedย overnight that city officials believe the water is safe. A boil water notice was issued out of an abundance of caution and to comply with regulatory standards, according to Houston Water Director Yvonne Williams Forrest.

“Our system maintained pressure. We never lost pressure fully,” Forrestย told KHOU. “So there was never an opportunity for anything to enter our system. They just fell below the regulatory requirements.”

Gov.ย Greg Abbottย directed state emergency resources to the city to help, and said he has been in contact with Mayor Sylvester Turner.

“Weโ€™re currently working to fulfill the cityโ€™s request for help with rapid turnaround of water sample results,โ€ Abbottย said in a statement.

This article was written by ย SNEHA DEY ofย The Texas Tribune. ย The Texas Tribune is a nonpartisan, nonprofit media organization that informs Texans โ€” and engages with them โ€“ about public policy, politics, government and statewide issues. ย This article originally appeared at:https://www.texastribune.org/2022/11/27/houston-boil-water/