| Austin American-Statesman
On a normal day, Ullrich Water Treatment Plant produces roughly half of Austin’s drinkable water and is crucial to keeping the city’s water system functioning.
State regulations require the plant to either have access to a backup power source or a substantial amount of water reserves in case the plant sees an unexpected shutdown. Ullrich has both.
So when a tree limb fell on an electric line leading to a substation that powered Austin’s largest water treatment plant on Feb. 17, backups should have snapped into place to keep power running and water production churning.
But there was a problem: Nobody on site knew how to operate a 52-year-old gear switch that would have restored power to the plant.
And so Ullrich Water Treatment Plant went dark for three hours in the middle of the worst winter storm to strike Central Texas in decades. It cut off roughly half of the city’s potable water production and deepened the winter weather crisis that at that moment had thousands shivering without electricity in their homes.
The outage resulted in the plant operating below capacity for more than 10 hours, according to Austin Water. During that time, water drained rapidly from the city’s water reserves, bled by thousands of burst pipes and dozens of broken water mains.
The failure of dual redundancies at Ullrich helped trigger a citywide boil water notice and contributed to widespread loss of water pressure that included forcing the evacuation of many patients from St. David’s South Austin Medical Center.
In the weeklong winter storm, the loss of power at Ullrich represents an inflection point when the city’s power crisis became a water supply crisis.
Ullrich had a second emergency power source and enough water storage to provide 100 gallons to each customer in case of a power outage. Yet the icy conditions revealed that Ullrich Water Treatment Plant’s dual redundancies — backup power and backup water storage — were unreliable when faced with weather conditions during the winter storm.
It was “literally a perfect storm,” Austin Water’s assistant director of operations, Rick Coronado, said in an interview with the American-Statesman.
Broken water mains and pipes rapidly began depleting the Austin’s reserve water stored in massive reservoirs even before the outage. So when the power went out, there was little water left in reserve to keep the system pressurized enough to push water out of faucets, bathtubs and spigots.
“The outage compounded an already difficult situation of keeping up with leaks and system demand that ultimately depressurized the water system,” Coronado said.
It is still unclear the level of impact the power outage at Ullrich Water Treatment Plant had on the overall water system. The city has not yet conducted an after-action report, and hearings have only just begun on what actually…