What you need to know about Houston's boil water notice

A boil water notice was issued in Houston on Sunday night, eight hours after a power outage knocked off service from the East Water Purification Plant.

Driving the news: The city is testing water samples and will send the results to the Texas Commission on Environmental Quality no earlier than 3am Tuesday to see if the water has been contaminated or if it's safe to use.

• The boil water notice will remain for Houston's 2.2 million residents until the city gets the green light from TCEQ, said Erin Jones, Houston Public Works spokesperson.
• Bellaire also announced a water boil notice in response to the Houston water pressure issue.

What they're saying: The city said the boil water notice is a precautionary measure and states that there is no evidence that the water has been contaminated.

• "There was no alarm. Even now, my notion is the water is safe," Mayor Sylvester Turner said at a press conference Monday morning. "We are optimistic the results will come back clean."

How to consume water: Boil water for at least two minutes and let it cool before drinking, washing your face, brushing your teeth or bathing.

• Do not use ice from automatic ice machines or chilled water from refrigerators.
• Use bottled water if you're unable to boil.

What's happening: Several school districts and colleges were closed Monday, including Houston ISD and Houston Community College. Houston, Aldine, Spring Branch, Channelview and Galena Park independent school districts; HCC; and several Lone Star College campuses said they would be closed Tuesday as well.

• Residents rushed to grocery stores on Monday to stock up on bottled water. Kroger says it is limiting water to two cases or gallons per customer as it is restocking its supply, per KHOU.
• Memorial Hermann saw a few minor delays in elective surgeries on Monday morning. Aside from that, the hospital activated its boil water notice procedures and is operational.
• George Bush Intercontinental Airport and Hobby Airport shut off their water fountains and are supplying free bottled water to travelers.

Flashback: The last time Houston was under a boil water advisory was during the 2021 deadly winter storm.

• The time before that was in February 2020 when a 96-inch water pipe burst, flooding a freeway and some neighborhoods on a sunny day.

Delay in communication

The first water pressure alarm rang just before 11am Sunday, but city officials issued the boil water notice at about 6:40pm.

Why it matters: It is still unclear whether any water consumed by Houstonians between those hours is cause for concern.

• Turner has twice said the city's water is safe despite the notice, which he said was issued out of an "abundance of caution."

What happened: Both the primary and backup transformers funneling power to the city's East Water Purification Plant failed for an unknown reason Sunday morning.

• The outage caused a dip in the city's water pressure for more than four hours.
• 14 of the city's 21 water pressure sensors reported critically low pressure for two minutes, while two others reported critically low pressure for a half-hour.

Only around 6:40pm, after consulting with the TCEQ, did the city issue the alert.

• Turner said it was initially unclear whether the drop in pressure rose to a level that triggers a boil water notice.
• The city at first relied heavily on social media and news outlets to get the word out but eventually sent a text alert hours later.

Be smart: To sign up for the city's text and email alerts in the future, visit AlertHouston.

This story was updated to include details from the mayor's press conference.