Interstate 35 Expansion, Austin, Texas

Interstate 35 on its route through the heart of Austin is notoriously congested, and its traffic is a constant topic of complaints and news coverage. Commuters are desperate for a fix. But a proposal to add miles of new lanes will likely only exacerbate the problems that led to congestion in the first place.

Map credit: Map tiles by Stamen Design, under CC BY 3.0. Data by OpenStreetMap, under ODbL.


Status: Study and review
Originally reported cost: $8.1 billion

Current status update:

As of July 2022, I-35 widening through Austin is in study and review.

Update from Highway Boondoggles 7: I-35 widening through Austin continues to get pushback

Highway Boondoggles 4, in 2018, covered a plan to expand a section of Interstate 35 (I-35) through downtown Austin, Texas. The multi-billion dollar four-lane expansion of the interstate would run counter to the city’s mobility goals, which include expanding access to walking, biking and transit infrastructure, and would add to the state’s already enormous transportation debt. In 2018, the plan was on hold because of disagreement over whether the new lanes would be tolled, but the Texas Department of Transportation (TxDOT) is moving ahead with non-tolled lanes and is in the late stages of planning and study for the project, which would cause I-35 to become 20 lanes wide in some sections. Some of TxDOT’s proposed designs would displace up to 140 households and 70 commercial properties.

After loud and consistent criticism from Austin residents and local community groups, TxDOT proposed a modified alternative design in early 2022 that would lower the highway, combine frontage roads on one side, and allow green space to be built on top of the highway through the downtown section. That plan, however, would make the city and its residents pay the $600 million to $800 million cost of the highway “caps.” In March 2022, it was revealed that TxDOT’s original plans and proposals had used outdated maps and data, and that the agency’s designs could require the demolition of a 70-unit affordable housing community that was supported by both city and federal funds and which only opened in 2019. Although some of the alternative designs proposed by TxDOT would avoid that development and some of the other properties that could be seized by eminent domain, TxDOT has not endorsed any one of the designs.

In the spring of 2022, Austin’s city leaders expressed to TxDOT their concerns with the process and the proposals the agency has put forward. Citing climate change, the futility of highway expansion due to induced demand, the city’s goals around transit and active transportation, the need for safety, and the damage that I-35 has done to surrounding communities, they asked for design alternatives and a planning process that take their priorities into account.

Though one city councilmember said that the construction of I-35 created a “wall that reinforced segregation” and the mayor has argued that the expansion won’t even help the congestion problem, the city does not have the power to stop the project. Furthermore, though the parks that would cover the highway in one of the alternative designs are unfunded as of spring 2022, the influx of money from the federal Infrastructure bill passed in 2021 – much of which is earmarked for highways – means Texas has the money to push ahead, despite objections. TxDOT anticipates beginning construction on the northern and southern sections of the project in 2022, picking a final design for the central section by 2023 and beginning construction of that piece in 2025.

A further major issue with TxDOT’s I-35 plans has been highlighted in a lawsuit filed against the agency in June 2022 by TexPIRG, Environment Texas and the Rethink35 campaign. The lawsuit claims that by splitting its overall I-35 expansion project into three separate sub-projects – the I-35 Capital Express North (SH-45 N to US-290 E), South (SH-71/Ben White Blvd to SH-45 SE), and Central (US-290 E to SH-71/Ben White Blvd) projects – TxDOT is falsely claiming that these three stretches of roadway are “independent utilities” in order to avoid having to submit the project as a whole to the more rigorous environmental review and public participation required by law for a single larger project. Splitting the I-35 project into separate parts in this way, the lawsuit argues, is a clear violation of the law on TxDOT’s part, the size of the overall project such that it should be submitted to full environmental review and proper public scrutiny.

Original story from Highway Boondoggles 4, 2018:

Interstate 35 on its route through the heart of Austin is notoriously congested, and its traffic is a constant topic of complaints and news coverage. Commuters are desperate for a fix. But a proposal to add miles of new lanes will likely only exacerbate the problems that led to congestion in the first place.

The proposal being put forth by Texas officials would add four new lanes (two in each direction) along approximately 33 miles of I-35 traveling north-south through Austin. The project is the largest piece of a massive $8.1 billion collection of projects up and down I-35 in the Austin area.

Just as road expansions elsewhere in Texas have failed at reducing congestion – like Houston’s Katy Freeway expansion – any congestion benefits from widening I-35 will likely be short-lived. Austin’s suburbs of Georgetown, north of the city, and San Marcos, south of it, both saw population grow by more than 35 percent from 2010 to 2016. If those cities continue to see population growth as in recent years – which seems likely if encouraged by a wider highway connecting them to Austin – I-35 will quickly fill up with cars once again.

An I-35 expansion would also drain money from other pressing transportation needs. In 2012 Austin adopted a city vision for limiting sprawl, expanding transportation choices, and creating more compact, connected communities. Achieving that vision will require a variety of projects. These include building better bike and pedestrian infrastructure downtown, like the improvements proposed for the Guadalupe Street Corridor that would cost $33.7 million. Various proposals have called for creating new light rail routes through the heart of Austin, at a cost of $400 million to $1.4 billion.

Texas’ enormous appetite for new roads – including the addition of 12,000 new lane-miles from 2000 to 2016 – have already drained money from the budget and forced the state to make difficult financial decisions. Texas has shifted billions of dollars to pay for roads and road debt from elsewhere in its budget, as the result of both Proposition 1 in 2014 and Proposition 7 in 2015. As of 2015, Texas owed $29.1 billion in highway debt, second-most in the country, and 30 times more than it owed in 2000. In 2014, Texas paid $4.8 billion just to service its debt, 90 times more than in 2000.

As of February 2018, the I-35 highway plan is on hold, because the Texas Transportation Commission decided not to support any roads with tolled elements. However, local officials are still pushing to move the project forward.




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