AUSTIN (KXAN) — In the past four years, Austin residents have experienced three boil water notices and other water quality concerns, and Austin Mayor Pro-Tem Alison Alter wants to find out why.

“This is a pattern that is problematic, and one that we need to be looking at, you know, in a different way,” said Alter, referring to issues with zebra mussels, as well.

At least five members of Austin City Council are backing Alter’s call for an external audit of Austin Water after a citywide boil water notice was issued this past weekend — one of whom is council member Vanessa Fuentes (District 2), who’s also the chair of the Austin Water Oversight Council Committee.

“My biggest question is what exactly happened and could it have been prevented, and if so — why wasn’t it?” she said. “Austinites are rightfully frustrated.”

Austin Water issued the boil water notice Saturday night, estimating it will be in effect for at least a few days. The city said then the Ullrich Water Treatment Plant was out of service due to an “internal treatment process issue that resulted in high turbidity within the plant.”

On Sunday, Austin Water Director Greg Meszaros revealed the issue at the Ullrich Plant stemmed from a mistake made by operational staff.

Alter, who represents District 10, said she’s asking the city manager for an external audit of the water utility to dig into what happened over the weekend and to address water quality challenges the city has experienced in recent years.

“Bring in expertise from the water field who can help us to navigate what’s the technical part, with the operational part, with the investments that need to be made,” Alter told KXAN. “We have had several after action reports, and … we need to to make sure that we’re not looking at only, you know, individual recommendations and can see the forest of what’s going on.”

She also said there will be an internal investigation into this water incident, as well as hearings in the Austin Water Oversight Committee. The next meeting for the oversight committee is Feb. 23.

Austin residents will remember other times leaders have issued a citywide boil water notice: once in October 2018 and again last February during the winter storm.

“Austinites are resilient,” Alter said. “But resilience doesn’t mean that you shouldn’t expect and deserve to have basic services. And we need to do better.”

“I share in the frustration that many in the public have expressed about the most recent boil water notice and the frequency of these events,” Alter wrote on a council message board Monday afternoon. “While I appreciate the efforts our staff are making to restore water and distribute assistance, our community expects and deserves better.”

Alter said she is preparing a resolution calling for the audit to “examine our most recent incidents and identify appropriate protocol, operational, investment and other changes and actions.” Council members Kathie Tovo (District 9), Leslie Pool (District 7), Paige Ellis (District 8) and Mackenzie Kelly (District 6) are also joining Alter and Fuentes to co-sponsor the resolution, according to the message board.

During the council’s next meeting on Feb. 17, members will vote on whether to approve the audit.