Houston Boil Notice: How much longer will residents be under a boil water notice?

More than 2 million people across Houston have to boil water before using it because yesterday morning a transformer failed at the East Water Purification Plant causing a backup transformer to kick on. Then that one failed too.

"I will say stuff does happen. It’s unfortunate," says Houston Mayor Sylvester Turner. "A lot of people were impacted and are impacted. I certainly apologize for that."

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When two transformers quit working at 10:30 Sunday morning at the East Water Purification Plant "The electrical contractor (Saber Power) and Centerpoint Energy were onsite to investigate how not one transformer faulted, but the redundant transformer also failed," the mayor adds. 

Almost immediately 16 sensors showed water pressure levels below 20 PSI, pounds per square inch. 

"That was at 11:00 a.m. 16 of the 21 sites dropped below the emergency regulatory level of 20 PSI. Pressure rebounded above 20 PSI in less than 2 minutes at 14 of the 16 locations," Mayor Turner explains, and he says the other two sensors sat below emergency mandated levels for 30 minutes and full water pressure at 35 PSI was restored by 3:30 Sunday afternoon.

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So why wasn't the boil water notice issued until 6:40 p.m. Sunday with some residents receiving the alert at 10:30 p.m.? 

"We went through the process of calibrating the pressure reads and working with TCEQ over the course of the afternoon, and it really was at the end of the day that we said you know out of an abundance of caution and the fact that we did dip below that 20 PSI that the issuance needed to happen," says Carol Haddock Director of Houston Public Works. "There were questions throughout the course of the day whether or not we had actually tripped enough triggers to require it because they rebounded so quickly but we worked with them (TCEQ) on the data we did the back calibration and they (TCEQ) confirmed reviewing the data. They agreed and instructed us to move forward with the boil water notice."

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The Public Works Director says when pressure falls that low the water has trouble being pushed through the purification process, leaving the potential for bacteria and other contaminants to infiltrate the water.

At this point, preliminarily, nothing dangerous has been detected, but dozens of water samples have been taken. "The samples will then sit and incubate for at least 18 hours per state regulations...I have instructed public works to do an overall review of our system, a diagnostic review to see how we prevent this from happening again," the mayor explains, and he says he’s reviewing how to better spread the message to residents in a future emergency.

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The mayor says sample reading results to determine if the water is free from contamination are expected back at 3:00 a.m. and will be sent to TCEQ. Then it will be decided when the boil water notice can be dropped. 

This affects all of Houston except Kingwood and those serviced by Clear Lake Water Authority.