Austin’s $4.5B I-35 Overhaul Reaches Two-Year Construction Milestone
The eight-mile Capital Express Central program is advancing through separate bridge, roadway and drainage packages, with major work continuing toward 2033.
Austin’s I-35 Capital Express Central reconstruction has reached the two-year point since construction began in October 2024. The milestone concerns a long-running corridor program, not a newly awarded $4.5 billion contract.
The work extends roughly eight miles through central Austin. Its separate construction segments allow bridge replacement, drainage installation and roadway reconstruction to progress on different schedules while traffic continues using the corridor.
Project at a Glance
- Program:
- Approximately $4.5 billion
- Corridor:
- US 290 East to SH 71 / Ben White Boulevard
- Length:
- Approximately eight miles
- Drainage package:
- Two tunnels and a pump station
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Explore insights →A corridor rebuilt in packages
TxDOT’s program includes removing the existing upper decks, lowering mainlanes and adding two non-tolled managed lanes in each direction. It also includes changes to cross-street connections and facilities for people walking and cycling.
The segment structure matters. The Martin Luther King Jr. Boulevard work, Lady Bird Lake works, drainage infrastructure, University segment and Downtown segment are not interchangeable measures of progress. Completion of one part does not establish that the whole corridor is ready.
Drainage is a major construction workstream
TxDOT describes the drainage segment as two tunnels, a pump station and access shafts. The shafts provide maintenance and operational access to infrastructure that will remain largely below ground.
The agency lists a mid-2025 construction start and anticipated completion in 2029, weather permitting. That schedule belongs to the drainage package. It should not be substituted for the completion date of the entire Central project.
Lowering a roadway makes stormwater management integral to the permanent design. The drainage works therefore support the future highway configuration rather than functioning as a separate cosmetic improvement. Underground progress may be less visible than a bridge demolition, but it remains a significant part of the delivery sequence.
Why the work continues toward 2033
The Lady Bird Lake segment is scheduled across 2025–2033, illustrating the longer horizon for major corridor works. TxDOT’s published schedules identify different windows for different segments, rather than a single uninterrupted construction operation.
For nearby businesses and travelers, the relevant information is the current segment notice and traffic arrangement. A program anniversary is useful context, but it does not replace location-specific closure information or establish that a particular bridge or access road has reopened.
What comes next
The useful construction indicators are progress on tunnel and pump-station installation, bridge works, roadway staging and changes between traffic phases. Future reports should identify the package, location and date of each milestone.
The next steps also need to be distinguished from new procurement. Work already under contract can advance significantly without generating a fresh award. Confirmed drainage-team details are available to members below; no unverified appointments have been added.