Houston’s boil-water notice, issued Feb. 17, is expected to last through at least Feb. 22, Mayor Sylvester Turner told reporters Feb. 19.

Water pressure citywide is between 32 and 34 pounds per square inch, Public Works Director Carol Haddock said. A boil-water notice is mandatory when the city’s pressure drops below 20 psi and cannot be called off until pressure is maintained above 35 psi citywide and tested for bacteria, Haddock said.

“We’re making really good progress, but we’re still down to 20 psi in certain areas of town. ... We’re between 32 and 34 [psi] citywide. Those pockets of low pressure are coming up as well,” she said.

Calling off the boil-water notice also requires approval from the Texas Commission on Environmental Quality.

The city’s water pressure fell early in the week due to frozen generators and large numbers of residents dripping taps or experiencing burst pipes. As of Feb. 18, there had been nearly 5,000 calls to 311 reporting burst pipes, although the actual total number is likely much higher, Turner said.

To use water safely, residents must boil it for two minutes before drinking it or using it for cooking, according to the Houston Health Department. It can be used for brief showers; however, those with compromised immune systems are encouraged to limit bathing with it, Haddock said.

The city and Harris County are in the process of establishing a relief fund for residents struggling to afford food, water and repairs in the wake of the week’s winter storm damage, Turner said.