Urban highways are preventing us from meeting our neighbors and building community, according to a landmark new study. Luca Aiello, professor of data science at the IT University of Copenhagen, shares his research into the impact of freeways on social networks. The findings are important not just for our right to pursue happiness, but also for our pocketbooks.

https://www.pnas.org/doi/10.1073/pnas.2408937122

In a lean budget year, California has shrunk the size of its climate investments while still spending hundreds of millions of dollars on freeway expansions. Carter Rubin, director of state transportation advocacy at the Natural Resources Defense Council, joins the podcast to talk about his research into the state's mixed priorities in transportation spending.

Research on HOV/toll lanes: https://ww2.arb.ca.gov/sites/default/files/2021-04/18RD022.pdf

Traffic is a huge problem in Tijuana and San Diego. If you drive around during the day, you will most certainly be caught in a traffic jam. So should we build more roads to ease traffic congestion? In this crossover episode with Port of Entry, KPBS' border podcast, we explore what is keeping residents of Tijuana from a better quality of life. The answer took us by surprise.

If you enjoyed this episode of Port of Entry, check out their current season on Visionaries and Shapers of the Borderlands. You can check out their catalog for older episodes here or wherever you get your podcasts!

City Limits, a new book from journalist Megan Kimble, chronicles the emergence of a modern wave of freeway revolts in Texas. As the Texas Department of Transportation seizes more and more land to widen its highways, people who had never considered themselves urbanists or activists are joining the movement. This time they're not just fighting displacement, pollution and segregation — they're also fighting climate catastrophe.

The California legislature is starting a conversation about how to reunite communities that were divided by freeways. For Assemblymember David Alvarez, the issue is personal. Alvarez grew up in San Diego's Barrio Logan, one of the most polluted communities in California. He's now chair of a special committee dedicated to correcting the kind of racial and environmental injustices his family has faced for decades.

Former Caltrans executive Jeanie Ward-Waller shares her story of getting fired after speaking out against a freeway project near Sacramento. She says Caltrans is driven by a "mindless impulse to add more freeway lanes," and that reform-minded people at the agency are often sidelined and dismissed.

Gustavo Dallarda, director of Caltrans District 11, explains some of the engineering behind freeways and makes the case that they provide an efficient means of travel compared to surface roads. He acknowledges the need to reduce vehicle travel, but says infrastructure doesn't get built overnight and that our transition away from cars and freeways has to be slow and gradual.

Our methods for measuring the economic impact of freeways are rooted in 1950s logic. A new report, "Divided by Design" from Smart Growth America, uncovers just how much they leave out. Co-author Beth Osborne says we tend to overestimate how much time and money we'll save on freeways. And we ignore the ways in which freeways can sometimes make trips longer. Divided by Design: https://smartgrowthamerica.org/program/divided-by-design/

Explainer on the value of time: https://www.youtube.com/watch?v=7_KLleAqjBs

Chuck Marohn, the founder of Strong Towns, has a bone to pick with the field of engineering: Too often, it uses freeway design standards on local streets. Marohn spoke with Andrew as he was promoting his book "Confessions of a Recovering Engineer." He argues engineers need to stop prioritizing speed over safety, and that cities need to stop trying to “solve” congestion.

As the CEO of San Diego County's transportation planning agency, SANDAG, Hasan Ikhrata has done more than anyone else to shake up the conversation around our freeways. Ikhrata has pushed his own board of directors to let go of long standing plans to widen certain freeways. And he's jump-started a debate over charging drivers by the mile to fund a more sustainable system.