Austin's most famous trail is on track to get a $25 million upgrade. A new boardwalk is planned for the south shore of Lady Bird Lake, replacing a cramped section of the Ann and Roy Butler Hike and Bike Trail between South First Street and Congress Avenue.
The Texas Department of Transportation (TxDOT) is paying for the boardwalk as compensation for taking several slices of parkland around Lady Bird Lake to make space for the expansion of I-35 through Central Austin.
The payments are required under a federal law that compels transportation agencies to replace or improve public parkland when it's used for highway projects.
Some of the parkland use is temporary, and TxDOT said it is paying the city based on the appraised value of the land. Other acquisitions are permanent, including about 1.3 acres of Waller Beach Park.
TxDOT will write the city of Austin a $25 million check and said the money can only be used for the boardwalk. Exactly when the money will be handed over is unclear as are some key details about the boardwalk, including when it will actually get built.
But a preliminary cost estimate prepared for the Austin Parks Department in June, obtained by KUT News through the Texas Public Information Act, paints the clearest picture yet of what the trail could look like.
The document describes a 760-foot-long boardwalk that would match the design and materials of the existing boardwalk. The path would be 14-feet wide with LED strip lighting along both sides. Three custom shade structures, estimated to cost $250,000 each, would be installed, according to the preliminary estimate.
The boardwalk could include nine benches, three trash cans and a dog waste station. The existing trail would be restored to natural vegetation.
The document pegs the total cost of construction at $14.3 million. That's almost $11 million less than TxDOT's promised funding, but the estimate does not include the cost of designing the boardwalk. The city has so far not explained how the remaining money would be used.
A nearby private development already under construction has imagined how the area might change. Marketing materials for One Lady Bird Lake, a 17 story mixed-use residential building, include renderings that show a boardwalk-style walkway extending in front of the Hyatt Regency next door.
TxDOT has been working with the city on the boardwalk since at least 2023, according to the state's in-depth environmental analysis of the I-35 expansion. Mayor Kirk Watson first revealed the $25 million price tag in a 2023 letter to opponents of the I-35 expansion.
The city declined an interview about the project.
The Trail Conservancy, a nonprofit that manages the trail and helped build the existing section of boardwalk in 2014 for $28 million, said the process was so early that a project lead hadn't been chosen yet.
"We'll still working on those details with the Parks Department and with TxDOT," Charlotte Tonsor, The Trail Conservancy's Executive Projects Director, told KUT News at a TxDOT open house last month. "We hope we can share those soon."
Tonsor confirmed the boardwalk is estimated to cost $25 million.
The Trail Conservancy has long wanted to upgrade this heavily used section of the Butler Trail. A 2021 report by the nonprofit said "slow zone strategies" should be employed until a boardwalk could replace the trail.
"This section, I find to be a little bit dated," said Lorraine Choy, who was out walking this week with her friend Miriam Helfgott.
"It's pretty narrow and now it's really congested," Helfgott said. "By the weekend, it's probably more than double the traffic, so we need a wider trail."
