Southwest Austin - Dripping Springs Edition | March 2022


The most recent boil-water notice, which lasted Feb. 5-8, was caused by human error during the water treatment process shown below.


Plant from Lake Austin. 1


Chemicals are added to the water to disinfect it, soften it, and encourage the minerals and other particles to clump together.

Austin Water pumps water into the Ullrich Water Treatment

Water enters the center mixing well of the basin and is mixed with solids, making particles stick together and sink.





As water leaves the clarier, A treated water moves around the skirt and up while B the solids sink to the bottom for disposal.

plants ramped up. By 8 p.m., the city was under its third boil-water notice since 2018. Austin Water placed the three over- night operators who were on duty during the incident on leave, where they remain pending further disci- pline. Meszaros resigned Feb. 11. Austin Water identied operator error at Ullrich as the root cause of the turbidity spike Feb. 4-5. Prelimi- nary reports on the incident said that alarms triggered by increased turbidity were working and did go o as Ullrich’s water grew cloudier Feb. 5. “There was not a call for help. … I don’t entirely know why,” Meszaros said. While no sign of any problem organ- isms was found in the compromised water, Ullrich’s water systems feed into Austin’s entire supply, and federal regulations require a boil notice to be issued if high turbidity is detected. “I made the decision. I said, ‘Let’s do a citywide boil-water notice.’ That’s the most protective of the whole city,” Meszaros said. Notices stackup Unlike the 2018 boil notice stemming from local ooding and the 2021 notice brought on by the eects of Winter Storm Uri, blame for the 2022 situation appears to lie with Austin Water opera- tors and response policies. In October 2018, historic ooding in the area kicked up sediments and overwhelmed Austin’s water ltra- tion, leading to Austin’s rst ever city-wide boil-water notice. Meszaros and local experts said then that the ooding fallout was beyond Austin’s system capabilities, especially after drought conditions that worsened the sediment issue. All of Austin once again faced a his- toric natural disaster in February 2021 with Uri disabling water and power systems statewide. Austin Water, like many other Texas water provid- ers, entered boil-water conditions for



residents after more than a century without experiencing similar issues. Austin Water is currently searching for new leadership, completing its own review of the February break- down and anticipating an external audit of its practices. While in the process of improving its systems, Austin Water is also con- tending with a continued loss of its most experienced personnel—includ- ing Greg Meszaros, its director of 15 years. The utility is faced with ensur- ing it is resilient enough to supply an ever-growing city. “This was really about our opera- tions of the plant. How we communi- cate, how we make decisions, how we respond to alarms, how we escalate. Those are all within our control, and ... ultimately preventable,” Meszaros said Feb. 15. “I’m just profoundly sorry that Located just west of the Colorado River and Tom Miller Dam, the Ull- rich Water Treatment Plant is Austin Water’s largest and most central treat- ment plant responsible for the daily production of around half of the drink- ing water in Austin. Late Feb. 4, one of Ullrich’s seven treatment basins startedup as usual but saw rising turbidity levels by early Feb. 5, according to preliminary reviews. Measuring water turbidity, or clarity, is a key piece of treatment monitoring as higher readings can signal potentially harmful microorganisms in water. By 6 a.m. conditions in Basin 6 were completely out of control. At that point, Meszaros said heavy water clogged up the system and spilled into the clean water supply. The contamination was ocially logged around 8 a.m. Feb. 5, after which Ullrich’s citywide pumping shut down, and water production at Aus- tin Water’s remaining two treatment we had this event.” Monitoringmissteps

NTU stands for nephelometric turbidity units. Higher turbidity, or cloudiness, signals more particles in the water. The normal range is up to 10 NTU at this point. Ullrich Basin 6 was started

Feb. 4, 10 p.m.

Feb. 5, 2 a.m.

Feb. 5, 6 a.m.

Breakdown of what went wrong

The February boil-water notice took place as a treatment basin, or clarier, was brought online. Solids are added during that start-up process to help separate particles in the water. Too many solids were added, causing high turbidity leaving the basin, overwhelming the lters and aecting the drinking water supply.

8.7 NTU

21 NTU

145 NTU: Austin Water Director Greg Meszaros described this as “totally out of control.”


Settled water is treated to lower the pH and stop further mineral build-up.

7 Finished water is collected in a clearwell, or holding tank, before it is distributed through the city’s 3,000 miles of pipes.


The water passes through a line of lters. Remaining particles are captured.

around one week due to system fail- ures and infrastructure damage that caused low pressure across the city. The city has experienced several small-scale and localized boil inci- dents over the years as well with causes ranging fromcontaminant con- cerns to low pressure. Austin Water is typically on the lookout for such issues, and the Texas Commission on Environmental Quality outlines several reasons a utility may have to issue a boil-water notice, including decreased pressure—as in the case of Uri—or the detection of E. coli. Desmond F. Lawler, a University of Texas engineering professor with water treatment expertise, said he does not see the three recent citywide boil-water notices as a trend or reason for widespread concern about the sys- tem. However, he said the human error in February stands alone.

“When a boil-water notice happens because … of the oods four years ago or when they happen because of mas- sive power losses all over the city as happened 13 months ago, it’s easily chalked up to so-called acts of God— extraordinary circumstances that overwhelm an engineering system,” Lawler said. “When something hap- pens because of human error … it’s a little bit more dicult to excuse.” Strengtheningsystems Following a series of City Council hearings, ocials unanimously voted Feb. 17 to launch an external audit of Austin Water and its activities in recent years. The wide-ranging consultant report could cost between $200,000 and $1 million, and it will focus on areas such as the utility’s management of boil-water events, its best practices, and future planning around Austin’s



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