TxDOT to kick off I-35 Central project Wednesday with groundbreaking ceremony

AUSTIN (KXAN) — The Texas Department of Transportation will commemorate the start of construction on the Interstate 35 expansion near downtown Austin with a groundbreaking ceremony Wednesday afternoon.

The event will begin at 2 p.m. Wednesday on the rooftop of the East Campus Garage, located at 1200 E. Martin Luther King Jr. Blvd.

The I-35 Capital Express Central project is an eight-mile, $4.5 billion expansion and overhaul of the interstate between U.S. Highway 290 East and State Highway 71 and Ben White Boulevard. It comes as part of TxDOT's overarching MyMobility35 program, with two local projects already underway to address the north and south portions of I-35 in Austin.

The I-35 Central project plans include removing the upper decks along the corridor, expanding the highway and adding two non-tolled high-occupancy vehicle (HOV) lanes in both directions. The main lanes will be lowered between Airport Boulevard and Lady Bird Lake, and TxDOT crews will construct "boulevard-style segments" along downtown and improve pedestrian and bicycle amenities.

TxDOT officials said last month the state agency would tackle the project in six phases, beginning with the reconstruction of the Martin Luther King Jr. Bridge. That portion comes with an estimated cost of $34.4 million and is expected to finish work in early 2026, a TxDOT spokesperson told KXAN in mid-September.

Next up is the Lady Bird Lake segment, running from Holly Street to SH 71 and Ben White Boulevard. Work on this section is expected to begin late this year or early next year and wrap in 2031. This phase's enhancements include:

• The reconstruction of the Lady Bird Lake bridge
• The addition of two high-occupancy-vehicle managed lanes in each direction
• The construction of a single-point urban interchange (SPUI) at Riverside Drive for access for CapMetro’s future light rail routes
• Creation of a pedestrian-only bridge at Woodland Avenue
• Addition of enhanced bicycle and pedestrian paths

That portion's cost is yet-to-be-determined, officials said, as the project has gone out for bid and is awaiting a final dollar amount.

TxDOT will begin constructing two drainage tunnels and a pump station in mid-2025, with construction anticipated to complete sometime in 2028. That phase of work will cost roughly $748 million.

The state agency will also construct an elevated bridge for CapMetro's Red Line to cross south of Airport Boulevard, as well as build pedestrian and cycling paths. This phase of work also incorporates reconstructing the Red Line crossing at Fourth Street and a planned crossing for Project Connect at Riverside Drive.

Work is estimated to cost approximately $228 million, with a construction start eyed in early 2026 before culminating in 2029.

In a few years, TxDOT will construct the two HOV lanes in each direction from U.S. Hwy. 290 East to Martin Luther King Jr. Boulevard alongside reconstructed east-west crossings at Manor Road, Dean Keeton Street, 32nd Street, 38 1/2 Street and Wilshire Boulevard. Work on this segment is anticipated to run around $1.6 billion, with a possible start date in mid-2027 and completion in 2032.

In the downtown corridor, there will be two added HOV lanes in each direction between Martin Luther King Jr. Boulevard and Holly Street alongside the addition of a new frontage road boulevard running through downtown. TxDOT crews will also reconstruct east-west crossings at Cesar Chavez, Fourth, Fifth, Sixth, Seventh, 11th, 12th and 15th streets, along with building pedestrian-only bridges at Third, Fourth and 15th streets.

Work will cost around $1.5 billion, with construction poised to begin in late 2027 before an expected 2032 completion.

More details on the I-35 Capital Express Central program are available online.