Austin council weighs smaller 160‑foot I‑35 lid as cost‑saving alternative to larger caps

Mayor Kirk Watson opened a council work session May 26 to revisit the city’s I‑35 “cap and stitch” program ahead of an advance funding deadline with TxDOT.

Watson said he proposed a revised option intended to deliver a visible, shorter term benefit to taxpayers while reducing near‑term costs. “Dollars 41,000,000,” he said when describing the mayor’s 160‑foot proposal—an amount staff said could be supplemented to future‑proof nearby 11th and 12th Streets.

The nut graf: Councilmembers debated whether smaller, earlier‑deliverable land bridges provide meaningful mobility, economic or community benefits compared with larger caps and long‑range future‑proofing the council previously approved. The discussion touched technical feasibility, sound mitigation, construction schedules and how to pay for later phases.

Several public speakers urged the council not to reduce prior commitments. “I hope you don't claw back,” said Andrew Clements, a remote speaker who urged the council to preserve funding so future caps remain buildable. Tom Wald, executive director of the Red Line Parkway Initiative, argued the earlier $104,000,000 commitment should be kept. “I encourage you all to support… all the initial investments,” he told the council, citing expected ridership and redevelopment potential around transit stations.

Staff and TxDOT described the tradeoffs. Assistant City Manager Sam Rogers told the council the 160‑foot option could be built with funds already committed if the city slightly adjusts scope and that the smaller lid could tie into Waterloo Greenway. Tucker Ferguson, Austin district engineer for TxDOT, said lowering the roadway itself will reduce noise and that a 160‑foot lid would provide additional sound mitigation. “By virtue of lowering the entire highway through the downtown core, we'll achieve some sound mitigation throughout,” he said, adding that lids under 800 feet typically avoid jet‑fan ventilation requirements that add cost and complexity.

Councilmembers questioned whether the smaller stitch would deliver long‑term economic returns. One member cited prior ROI work showing the Cesar Chavez segment’s outcome depended heavily on a now‑lost federal grant; another emphasized that parks and public spaces often return community benefits that do not show up in fiscal ROI calculations. City consultant Mark Gilbert described examples of small lid projects elsewhere where retail and food‑and‑beverage tenants helped activate the space.

Finance staff briefed council on funding options: combination use of a SIB loan and certificates of obligation covered some earlier commitments, but later phases likely will need voter‑approved bonds, philanthropic partners or private fundraising. Staff said the Downtown Austin Alliance and other partners are in preliminary discussions about fundraising and partnerships.

TxDOT stressed the schedule constraint: designers are finalizing packages now and the project’s larger construction packages are timed to bid in 2028–29. Ferguson said design changes can still be incorporated at this stage but that the window for future adjustments is closing.

The council did not take a vote during the work session. Mayor Watson closed the discussion by reiterating the time sensitivity and thanking TxDOT and staff for their work; staff were directed to continue coordination and provide materials ahead of the council’s formal agenda meeting.

Next steps: the council will consider the item at its formal agenda meeting later in the week and must decide whether to authorize or modify the advance funding agreement that triggers design commitments with TxDOT.