Approximately 2.3 million Houston residents have been told to boil their water after a power outage impacted the city’s water purification plant.

Per The New York Times, residents were told that the power outage caused water pressure to drop, and as a result, public schools have been closed on Monday. “Everyone should boil the water before drinking, cooking, bathing, and brushing their teeth,” the city cautioned, citing regulatory requirements to issue a mandatory boil water notice.

In a pair of tweets, the Houston mayor’s office said that it is believed the water is “safe,” but the Texas Commission on Environmental Quality must give approval before the notice is suspended. “The city is submitting its plan to TCEQ for approval tonight,” the tweets from Sunday evening read. “Water samples will subsequently follow and hopefully we will get the all clear from TCEQ. The city has to wait 24 hours from that point before the boil water notice is suspended. The earliest would be tomorrow night or very early Tuesday morning.”

In a statement, Texas Gov. Greg Abbott said the state is “immediately responding and deploying support to Houston” in an effort to get safe water supplies back. “We urge those that the boil-water notice affects to continue heeding the guidance of local officials and take adequate precautions,” he added. "Together, we will ensure our fellow Texans are supported while the city's water supply returns."

A boil water notice was issued by the Houston Public Works during the winter storms of February, 2021. Earlier this year, “errors” at a treatment plant in Austin forced over one million residents to boil their water.