Austin pipes leaked enough drinking water in 2022 to fill Lady Bird Lake nearly 3 times

AUSTIN (KXAN) – From service-line drips to main-line cascades, Austin Water’s pipes leaked more than enough treated water to fill an Olympic-size swimming pool every hour of every day last year.

In total, city pipes lost over 6.9 billion gallons of drinkable water in 2022. That’s enough to fill Lady Bird Lake nearly three times, and it’s an increase of more than 400 million gallons compared to the year before, according to water loss audit data obtained from the Texas Water Development Board.

While 6.9 billion gallons may seem like a staggering amount of treated water, it’s less than the city’s all-time high of 7.3 billion gallons leaked in 2020. Last year’s leaks were also within a satisfactory range, according to an industry measurement called the “infrastructure leakage index,” which takes into account a utility’s total connections, miles of pipes and water pressure, the city said.

Austin Water Utility said some lost water is unavoidable in a system of Austin’s size. Each year the number and size of leaks varies, and the year-to-year increase in leaks last year was “part of that normal variation,” an Austin Water spokesperson said in a statement.

Austin Water said it has a “rigorous water loss control program” that includes a 90% response rate within three hours of a reported leak, as well as pipe renewal programs and smart meter installations.

“We are also constantly striving to reduce our losses,” the utility said in a statement.

Austin Water serves more than 1 million retail customers, has over 250,000 retail connections and more than 4,000 miles of main lines, according to audit data.

Real vs. apparent

The 6.9 billion gallons of lost water are categorized as “real water” losses, meaning physical water lost from the system. Those real gallons don’t include "apparent losses,” which are accounting losses, such as water that was used but not billed for. Apparent losses can happen due to inaccurate meters, billing errors and unauthorized consumption, according to TWDB.

The city tallied 1.5 billion gallons of apparent losses last year, according to audit data. The total cost of the real and apparent losses exceeded $12 million last year, according to TWDB’s data.

Austin Water said its My ATX Water project is in the process of swapping more than a quarter million analog meters with smart meters that provide more accurate digital readings and reduce apparent losses. The project will also expand the utility’s leak detection network and pressure sensors and provide more leak alerts.

“Since the project launched in 2021, it has estimated 226.8 million gallons in leak savings for our customers,” the utility said.

In Texas, retail public water systems that have at least 3,300 connections, or financial obligations with TWDB, are required to file annual water loss audits.

“Completing the Water Loss Audit will help a utility understand where and how much water is being lost from the distribution system and will provide a baseline to track and improve water loss control,” according to TWDB’s website.

Each water loss audit includes the infrastructure leakage index grade, “an excellent performance indicator for comparing performance among water utilities,” according to TWDB.

Leakage index

The closer the index number gets to zero, the lower the utility is keeping its leaks. The index is calculated with a formula that incorporates water pressure and the number and density of connections, according to the International Water Association.

Austin received an infrastructure leakage index grade of 4.09, its second highest yearly grade since 2008.

“Our Infrastructure Leakage Index has fluctuated over the last decade but remains within industry recommended range,” the city said. “According to the American Water Works Association and the Texas Water Development Board, a utility experiencing moderate water supply constraints like those at Austin Water should target an Infrastructure Leakage Index of between 3 and 5. Austin Water’s goal is to have an ILI below 3 within the next few years.”

According to TWDB guidelines, different water systems may strive for different leakage index targets depending on the availability and cost of water, and the system’s operating capacity. In a location with limited and costly water, a water supplier may want a leakage index between 1 and 3. In an area where water is “plentiful, reliable and easily extracted,” a water system may shoot for an index of 5 to 8. But an index above 8 is “not an effective use of water as a resource,” according to a TWDB guide.

Austin water says it needs to keep its leakage index under 5. The system is currently succeeding although it's had an upward trend over the past decade.

Austin compared to other water utilities

How does Austin stack up against the largest suppliers in Texas? According to statewide data, Austin’s leakage index is in the middle of the pack, compared to Texas’ other largest utility systems.

The chart above shows a comparison of leakage indexes versus the length of water mains in the 30 largest Texas water utility systems. The size of the dots relates to the number of retail connections in the system.