City looks for silver lining in TxDOT’s I-35 expansion

With the Texas Department of Transportation circling in on finalized plans for Interstate 35, city staffers are racing to seize opportunity of a number of cap-and-stitch projects that could come to be a silver lining in the largely unpopular interstate expansion.

In a biannual update Jan. 19, Corridor Program Office Director Mike Trimble caught City Council’s interim Mobility Committee up to speed on Our Future 35’s cap-and-stitch program, poised to kick into gear once TxDOT officially settles on a design this summer. For now, the team has shared preliminary concepts for TxDOT’s Preferred Alternative 3, featuring civic spaces above large swaths of downtown and UT campus among its most ambitious projects.

The design would add two high occupancy vehicle lanes and depress the highway about 25 feet below ground level to accommodate green space and east-west connections overhead. Right now, the bulk of these new structures would stretch over the interstate from Cesar Chavez to Eighth Street and 15th Street to Dean Keeton, though staff are also eyeing a project near the Red Line crossing at Airport Boulevard.

Trimble noted the specifics will remain vague until deciding what will be placed up top, as the caps’ engineering will depend largely on the necessary load-bearing. Anticipating a supporting capacity of one- to two-story structures, staff are looking to projects like Dallas’ Klyde Warren Park for inspiration, though constraints on building intensity are yet to be determined by a TxDOT geotechnical analysis. When that’s complete, the challenge will be executing a coherent vision in step with TxDOT’s “aggressive” timeline, which has construction beginning as early as 2024.

Also on the table are a number of stitches, or widened crossings, across intersections at Woodland, Holly, 11th, 12th, 32nd, 38th½, and 41st streets, as well as near Capital Plaza just south of U.S. Highway 290 E. With TxDOT already planning to widen bridges by 20 feet across, Trimble says there are a host of opportunities for multimodal enhancements like sidewalks, bike lanes, landscaping, public art, and other pedestrian amenities.

While TxDOT has agreed to accommodate the cap-and-stitch projects in its design, the looming question is how the city plans to scrape up nearly $800 million in funding for their construction, not to mention ongoing maintenance costs. Staff members are currently working on an emerging projects agreement with USDOT’s Build America Bureau, which they hope will lead to some federal grant and loan opportunities. Still, the price tag will likely require some kind of public-private partnership ($50 million of Dallas’ $90 million in funding for Klyde Warren Park came from private investment and donations).

Council Member Chito Vela, who represents the stretch of I-35 from 51st Street to Highway 290, also noted a lack of investment toward the project’s northern borders. With the bulk of cap projects concentrated in downtown and the UT campus, Vela sees a lost opportunity to lay groundwork for the economic development of more underserved neighborhoods like Windsor Park, pointing to the growth surrounding Boston’s Rose Kennedy Greenway as an example.

“From a property tax and real estate point of view, those areas of Boston around Rose Kennedy Greenway just blew up in value … from warehouses to a residential and commercial district that is one of the most vibrant in the city,” Vela said. “I think it’s a great idea in the downtown area, I think it’s a great idea at UT, I just think it’s a great idea through the entire stretch of the freeway. We only have one chance to do this, and I just really want to get it right to get the maximum public benefit for the citizens of Austin.”

Rendering courtesy of the Urban Land Institute.

The Austin Monitor’s work is made possible by donations from the community. Though our reporting covers donors from time to time, we are careful to keep business and editorial efforts separate while maintaining transparency. A complete list of donors is available here, and our code of ethics is explained here.