Water Conservation: The Broken River, Part 1

by Paul Robbins
Can Fixing Austin’s Leaking Water Pipes Replace Water Treatment Plants?
​
In This Story…
​
• Leaks in Austin’s 3,900 miles of water pipelines resulted in the loss of over 9 billion gallons per year in 2024, about 17% of total water supply.  This is enough water to fill Lady Bird Lake twice a year.

• Almost 80% of these leaks came from old Polybutylene service lines and Cast Iron pipe.  The overnight cost to replace this would be about $1.7 billion (in 2025 dollars).

• Despite considerable expense of water leaks, the City of Austin only replaces about 1/5 of 1% of its water pipe system per year.

In 2010, the City of Austin exercised stupendously poor judgment in building a fourth treatment facility at the edge of Lake Travis, now known as Handcox Water Treatment Plant.  The cost was $529 million plus interest ($871 million in 2025 dollars).  And in the tradition of bureaucracies stuck in archaic business models, the City recently commissioned a doubling of Handcox capacity, from 50 Million Gallons Per Day (MGD) to 100 MGD, to be completed by 2031.

When completed, Austin will own 385 MGD of capacity.  This is 69% more capacity than it has ever used since the launch of comprehensive water conservation actions implemented in 2007.  The most recent cost estimate is $145 million plus interest (2025 dollars).

Ironically, while Austin is treating all of this water, it has a gigantic leak problem.  In 2025, Austin Water operated 3,917 linear miles of pipelines delivering water over a service area of 548 square miles.  These ranged from small service lines to individual homes 2 inches or less in diameter all the way up to large service mains 7 feet wide.  And this infrastructure leaked about 17% of the water it transported, about 9.3 billion gallons, in 2024.  This is enough to fill Lady Bird Lake twice a year.

Over time, the leaks have actually gotten worse, from 13 gallons per person per day in 2007 to as high as 23 gallons in 2024.  Most of these leaks are not the streams and occasional geysers seen on Austin streets.  Rather, they are hidden below ground.  

Water leaks are common in a municipal water system as old as Austin’s.  However, this huge volume of lost water in a water-scarce area is alarming and unacceptable.

This leads to the question: can fixing Austin’s underground pipes economically compete with new water treatment plants and new water supply sources?

The Mirage of a Dependable Water Supply

In 1999, Austin paid the Lower Colorado River Authority (LCRA) $100 million to guarantee a future water supply of 350,000 acre-feet a year until the year 2050.  This is about double the volume that the city currently uses.  This seems like a huge amount, but it only exists on paper.  In a serious drought, this supply cannot be depended on.
  
A recently published story on future water supply shortages in Central Texas explained that drought, exacerbated with global warming, sediment that is filling the Highland Lakes, increased population, and stagnating water conservation efforts can cause acute water shortages in as little as 15 years.

The Worst Materials and the Cost of Replacement
About 80% of Austin’s leaks are found in two legacy pipe materials whose installations ceased decades ago: Polybutylene (PB) and Cast Iron (CI).

About 22% of Austin’s water leak volume occur in PB pipes.  Austin Water used this material beginning in the late 1950s, though its use greatly diminished by 1990.  By then, PB had become widely recognized for advanced deterioration when exposed to chemicals in water treatment such as chlorine and fluoride.  Expensive lawsuits against manufacturers ensued, and water utilities discontinued its use.  But the legacy…and the leaks, remain.  The overnight cost to replace PB service lines would be about $134 million.  

About 3/4ths of remaining leak volume is found in about 860 miles of older CI pipe, even though Cast Iron material makes up less than a quarter of the network.  Given CI’s reputation as an inferior material, almost none has been installed in Austin since 1992.

It would seem like a simple matter to replace old Cast Iron.  But digging up streets and installing modern materials can cost about $1.8 million per mile. The overnight cost of replacing the City’s Cast Iron pipes would be almost $1.7 billion in 2025 dollars. 

As a point of comparison, the entire 2025 Austin Water budget, including debt payment, treatment plant operation, electric consumption, and salaries, was about $395 million.

A Repair System That Can’t Keep Up

It is not fair to say that Austin Water has completely neglected its troubled system.  In 2024, it spent almost $21.6 million to replace 7.5 miles (out of 3,917 miles) of water pipes.  Another $2.7 million in 2024 was used to replace failing PB service lines to buildings.  And another $12.5 million was expensed on above-ground “same day” water leak repair that year.

Despite this attention, its old system apparently cannot be fixed fast enough.  As the saying goes, “rust never sleeps.”  
​
In the case of Cast Iron pipe, you can take this literally.

PLEASE TAKE  5 minutes to send a message to the Water and Wastewater Commission and the Water Forward Task Force asking them to urge City Leaders to prioritize repairing Austin’s aging infrastructure and stop wasting billions of gallons of our precious water each year. Add a short, personal note if you can because real people sharing their concerns are what move decisions.

Speak Up for Smarter Water Management TODAY

Paul Robbins is an environmental activist and consumer advocate living in Austin.  He has been Editor of the Austin Environmental Directory, a sourcebook of green issues, products, services, and organizations, since 1995.