The Texas Department of Transportation (TxDOT) has committed $25 million to replace a popular Austin trail segment that would be affected by the expansion of Interstate 35. Trail users can expect some disruptions and detours in the near term, but agency leaders say the path will remain intact and ultimately be enhanced.
The I-35 Capital Express Central Project covers an 8-mile stretch of I-35 between U.S. 290 East and State Highway 71/Ben White Boulevard in Austin. Construction began in October 2024 with an estimated cost of $5.6 billion. Initial funding was set at $4.9 billion in 2020. The work includes adding two non-tolled managed vehicle lanes in each direction, lowering portions of the main lanes, removing upper decks, improving east-west crossings, enhancing bike and pedestrian infrastructure and reintegrating connectivity between East and West Austin. The Lady Bird Lake shoreline is one of the zones impacted as the project advances.
To mitigate trail loss from the highway expansion, new funding will support a boardwalk extension along the south shore of Lady Bird Lake. The existing deck is composed of precast concrete planks laid over a galvanized steel support system and concrete piers. The replacement is planned to match this material and design.
A preliminary cost estimate prepared for the city’s parks department describes a 760-foot-long, 14-foot-wide boardwalk with LED strip lighting on both sides, three custom shade structures, benches, trash receptacles and a dog waste station. The estimate places construction at about $14.3 million, with the remainder of the $25 million commitment covering design, engineering and related costs.
Coordination between TxDOT and Austin’s Parks and Recreation Department will be important, since the highway and boardwalk projects overlap in timing and geography. While no official start date has been announced for the boardwalk, the interstate project’s impacts in the lakeside zone are expected to continue into the early 2030s, with staging areas and detours already mapped through 2033.
Photo by Stuart Seeger, CC BY 2.0 https://creativecommons.org/licenses/by/2.0, from Wikimedia Commons




