AUSTIN, Texas — A new study has found that burying all of Austin Energy’s overhead power lines would cost $50 billion and require decades of work.
In February 2023, an ice storm knocked out power for hundreds of thousands of Austin Energy customers, largely as a result of weakened tree limbs falling on lines across the city. A month after the storm, the city council approved a resolution to look into what it would take to bury some overhead power lines.
At the time, then-Austin Energy General Manager Jackie Sargent said burying power lines might not be feasible.
“Many have asked why all of our distribution system isn’t underground, only some of it. We’ve always responded that varying our distribution lines would be prohibitively expensive and very disruptive,” Sargent said after the storm. “We as a utility know this intuitively, but the community may not. And we don’t have a feasibility study that illustrates the extent of what this would take.”
In August 2023, the city council approved $1 million for a study to analyze where Austin Energy could potentially bury more power lines. At the time, 57% of Austin Energy’s power lines were unground and the study was set to look at the existing 5,000 miles of line above ground to see where it might be economically and environmentally safe to bury them.
Now Austin Energy says it’s working to incorporate the results of that study, as well as another focused on “hardening” overhead lines in vulnerable areas.
For the “Underground Feasibility Study,” Austin Energy partnered with the engineering firm 1898 & Co. to study both the feasibility and cost of burying overhead power lines.
1898 & Co. concluded that it does not recommend a systemwide conversion from overhead to underground power lines. The firm also said that roughly 120 miles of Austin Energy’s lines may have benefits that exceed the costs, but other project solutions may be better than undergrounding.
The study also noted a variety of challenges to undergrounding, including:
- Environmentally sensitive or protected areas
- Limited space within underground easements
- Acquiring permits
- Telecommunication line relocation
- Rocky soils
- Traffic disruption
“[1898 & Co.] recommend[s] Austin Energy develop a highly strategic approach to undergrounding,” the study says. “Include study results and data in a larger strategy for reliability and resilience.”
In total, the study estimated that burying all of Austin Energy’s overhead lines would take decades and would cost $50 billion – approximately 25 times Austin Energy’s entire Fiscal Year 2025 budget.
What is Austin Energy doing to improve reliability?
Austin Energy said the two distribution system studies – the Underground Feasibility Study and the ‘hardening” study, expected to conclude in May – will bolster its ongoing reliability initiatives.
Those include supporting underground service design for new developments, wildfire mitigation by vegetation management efforts and the Pano AI wildfire detection system, “hardening” infrastructure to make electronic components and circuits resistant to damage or malfunction, and adding “smart” equipment to reduce outage durations.
“While all these efforts have historically been separate initiatives, we now see the need to bring these together with lessons learned together into one Comprehensive Distribution Resiliency Plan later this year,” said Bob Kahn, Austin Energy’s general manager. “This long-range, ongoing plan will outline Austin Energy’s strategies to make our grid more reliable and resilient for decades to come.”