AUSTIN (KXAN) — More than 100,000 gallons of wastewater flowed into a dry tributary bed of Bull Creek after there was a 21’’ main break and sanitary sewage overflow, according to Austin Water crews.

The overflow was discovered at 11:30 a.m. Sunday at 10801 Sierra Oaks. Austin Water says its crews were able to stop the leak by about 9:00 a.m. Monday and finished working on repairs, clean up and recovery by 5 p.m.

Austin Water managing Engineer Kevin Koeller says the wastewater never made it into Bull Creek, and crews are cleaning out what remains in the tributary bed.

“Any place that there’s wastewater ponded, we will pump that out and put it back into the wastewater collection system,” Koeller said.

The Texas Commission Environmental Quality has been notified, and the situation will not affect Austin’s drinking water. However, residents are advised to stay clear of the area in Great Hills Park.

Austin Water says it doesn’t have a timeline on when the park will reopen. Koeller says cleanup and repairs could take a week or longer.

Meanwhile, Koeller says Austin Water is working to make sure it doesn’t happen again.

“We actively look to repair pipes that have reached, before they’ve reached the end of their useful life,” Koeller said. “In this case, the pipe failed before that.”

Generally, the city’s concrete pipes have a life of about 50 years. The one that broke in this case was installed in the early 1980’s. It was only 37 years old. Engineers say a lot of the city’s sewage pipes were put in during the 1970’s and 1980’s, as growth in Austin boomed. Engineers run cameras through them regularly.

“We actively clean and televise our sewer system, and we look in these areas, we televise over 2,000,000 linear feeds a year,” Koeller said.

He says it’s rare that one busts so early, but now, crews are paying close attention to others that also may not seem old enough to break. 

 “We’re looking at similar pipes, similar age, in that area,” Koeller said.

On Sunday, Austin Water urged residents who use private drinking water supply wells located within half a mile of the overflow site to only use distilled or boiled water.

Austin Water said it does not believe there is any connection between this issue and a spill back in October that sent 25,000 gallons of raw sewage into Bull Creek near Old Spicewood Springs Road. In that case, the cause was a clogged line.