City trying to keep operating water plant submerged by Harvey

People and rescue boats line Tidwell at the east Sam Houston Tollway as rescues continue from flooding following Hurricane Harvey Monday, Aug. 28, 2017, in Houston. People and rescue boats line Tidwell at the east Sam Houston Tollway as rescues continue from flooding following Hurricane Harvey Monday, Aug. 28, 2017, in Houston. Photo: Melissa Phillip, Houston Chronicle Photo: Melissa Phillip, Houston Chronicle Image 1 of / 116 Caption Close City trying to keep operating water plant submerged by Harvey 1 / 116 Back to Gallery

If a horrific storm and thousands of rescue missions were not enough to occupy city officials, Houston now is scrambling to keep one of its three key drinking water plants online.

Rising levels in nearby Lake Houston submerged the city's Northeast Water Purification Plant about 6 p.m. Sunday, Mayor Sylvester Turner said.

"What that means is that we're trying to pump it out ... so that it doesn't cause the northeast water plant to go down," Turner said. "If we can't get it out, it will have an impact in our system."

Sources with knowledge of the situation said they expect the plant to go offline Friday, and said they were surprised it had not shut down earlier. If that occurs, residents in north Houston may receive orders to boil their water before using it.

That is because areas close to the northeast plant may have to pull water from distant sources, dropping the pressure in the lines and making it more likely the untreated groundwater or floodwaters could force its way into the pipes.

City spokesman Michael Walter said he could not confirm concerns about the plant's viability and said officials now are focusing on working with area chemical plants to obtain the pumps those facilities use in such incidents.

"We are waiting to hear about the status of the operation and then if there's any action that needs to be taken we'll announce that to the community," he said.

Shortly after 2 p.m., public works sent out an alert saying that "while (the northeast plant) remains operational, we are asking people to minimize water use at this time."

Howard Hilliard, chief administrative officer for the Department of Public Works and Engineering, said a key challenge is successfully pumping flood water far enough away from the facility that it does not simply flow back in.

"The plant is underwater and they can't get to the equipment, the filters, the pumps and such, to be able to do any adjustments or any maintenance on those pieces of equipment," he said. "We are continuing to come up with potential solutions to pump that water out."

Texas Commission on Environmental Quality spokeswoman Andrea Morrow said the plant was "functioning with good pressure and effective treatment" as of 3:30 p.m. and that city officials were communicating frequently with the TCEQ about the facility.

"The operators have taken protective measures against flooding and are working with the state for continued safe operation of the facility," she said.

Wayne Klotz, a Houston civil engineer, said it is not guaranteed that Houstonians will need to boil their water if the plant goes down. The plant has been shuttered before, he added, when floods upstream made the Lake Houston water cloudy with sediment and difficult to treat.

"They have plenty of capacity at their other two water plants, they have water wells across the city they can operate on for a period of time," he said. "The average citizen would never know it changed. They've got so many ways to feed that system I'd be shocked if they had pressure issues at this point."