AUSTIN (KXAN) — Work will soon begin on the Texas Department of Transportation’s Interstate 35 Capital Express Central Project, and project documents are giving a closer look into just much money each phase of the project will cost.
TxDOT has estimated a $4.5 billion sticker price for the eight-mile-long overhaul, with the project corridor running along I-35 from U.S. Highway 290 East to State Highway 71 and Ben White Boulevard. TxDOT officials have said the project will be divvied up into six phases of work, with construction to begin this fall with the reconstruction of the Martin Luther King Jr. Boulevard Bridge. The six phases include:
- MLK Bridge
- Lady Bird Lake
- Drainage tunnel under I-35 at Cesar Chavez Street
- CapMetro and Red Line bridges at Airport Boulevard and Fourth Street
- The University of Texas at Austin area
- Downtown
Martin Luther King Jr. Boulevard Bridge
That first round of construction work on the MLK Bridge is estimated to cost $34.4 million, with funding coming from both TxDOT and the Capital Area Metropolitan Planning Organization (CAMPO). That work begins this month and is expected to wrap in early 2026, depending on the weather.
This project includes reconstructing and widening the bridge to enhance connectivity and safety, per project documents. It’ll also include the addition of sidewalks, shade structures and a safety barrier along the bridge in addition to reconstruction entrance and exit ramps to and from I-35.
Lady Bird Lake segment
The next project to be tackled is the Lady Bird Lake segment, running from Holly Street to SH 71 and Ben White Boulevard. This segment of the project is projected to kick off work in late 2024 or early 2025. That construction is estimated to run through 2031 and will 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
A TxDOT spokesperson told KXAN Tuesday the project has gone out for bid and the state agency should have an actual cost soon, but added funding is coming from both TxDOT and CAMPO.
Drainage tunnel and pump station
TxDOT is installing two drainage tunnels along with a pump station to elevate stormwater management work along the corridor. Officials estimate the project will cost roughly $748 million with funding coming from TxDOT and CAMPO.
This phase of construction is expected to begin in the middle of 2025 and run through 2028, dependent on weather.
CapMetro and Red Line bridges
In this phase, TxDOT will build an elevated bridge for CapMetro’s Red Line to cross south of Airport Boulevard as well as add pedestrian and cycling paths. It will also involve reconstructing the Red Line crossing at Fourth Street, with a planned crossing to be built at Riverside Drive for Project Connect.
Costs are estimated around $228 million, with funding provided by TxDOT and CAMPO. Construction is expected to begin in early 2026 before wrapping in 2029.
University segment
From U.S. 290 East to Martin Luther King Jr. Boulevard, TxDOT will add two high-occupancy-vehicle-managed lanes in both directions along I-35. This phase will also include reconstructed east-west crossings planned at Manor Road, Dean Keeton Street, 32nd Street, 38 1/2 Street and Wilshire Boulevard. The state agency will also tackle reconstructing the Airport Boulevard intersection as well as adding a pedestrian-only bridge at the capital plaza.
This phase of construction is anticipated to cost around $1.6 billion courtesy TxDOT and CAMPO funds. Construction is expected to start in the middle of 2027 and run through 2032.
Downtown segment
Running from Martin Luther King Jr. Boulevard to Holly Street, TxDOT will add two high-occupancy-vehicle managed lanes in both directions along I-35. This segment will also feature the construction of a new frontage road boulevard running through downtown, reconstructed east-west crossings at Cesar Chavez, Fourth, Fifth, Sixth, Seventh, 11th, 12th and 15th streets, as well as the creation of pedestrian-only bridges at Third, Fourth and 15th streets.
This phase is set to cost around $1.5 billion and is using TxDOT and CAMPO dollars. Construction is anticipated at this time to start in late 2027 and wrap in 2032.
Other project features
TxDOT’s project will incorporate more than 19 miles of new shared-use paths as well as vehicle bypass lanes in an effort to minimize traffic at 28 intersections. It will also feature 13 connections to both the urban trail and bicycle networks.
The I-35 main lanes will be lowered and the upper decks removed as part of this project. New bicycle-pedestrian crossings are planned at Fourth and 51st streets, Lady Bird Lake and the Red Line at Airport Boulevard. Added bicycle-pedestrian crossings are planned at Third, 15th and 41st streets.