HOUSTON, Texas (KTRK) -- Water treatment experts break down what is being done to ensure Houston's water is safe, while city leaders spent Monday explaining why it took hours to notify the public.
Testing is currently happening with Houston's water supply to remove the boil water notice. City leaders said two transformers failed, and the generators didn't start immediately.
That caused the water pressure in the lines to fall. Experts say pressure keeps water moving, preventing other water sources from potentially getting inside leaks or cracks and causing health issues.
The water pressure levels dropped around 11 a.m. Sunday and it took more than six hours to decide on the boil water notice.
Mayor Sylvester Turner gave an explanation why.
"One of the reasons why it took that long is because 14 of the 16 sensors, remained below 20 PSI for less than two minutes, and for two sensors they remained below 20 PSI for 30. There were questions about whether a boil water notice needed to be issued," Turner explained.
The city issued the notice after talking to state environmental leaders. To remove the notice, testing needs to take place.
Experts said these tests can reveal specific indicators that the water is safe, but not all.
To make sure the water is safe, they need to let a water sample sit for 18 hours. That should be around 3 a.m. Tuesday morning.
If it clears, the notice could be lifted by the state. Sam Houston State University associate professor Ross Guida studies water treatment. ABC13 asked him what he would do when the boil water notice is lifted.
"By giving it this amount of time, I would say it should be flushed out of the system," Guida said. "They're not going to lift that boil water unless they're pretty confident the water is OK to drink. If it was me, myself, as soon as the notice is lifted, I would treat the water like we do too often for granted that it's perfectly fine."
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