A new Vice report analyzes transportation models ―conceived more than fifty years ago in the early days of national highway building― as the “broken algorithm that poisoned American transportation.”
By Chris McCahill The greater Cleveland area is coming to terms with the sometimes-messy impacts of repeated highway expansions. For decades, highway capacity investments have caused the area’s dwindling population to simply move around and …
As the transportation field gradually moves away from its singular focus on high motor vehicle speeds and its reliance on motorist behavior to set speed limits, NACTO has just released comprehensive guidance on speed limits on surface streets in metro areas.
By Eric Sundquist The longstanding tradition of setting speed limits at the 85th percentile of observed vehicle speeds is increasingly under scrutiny, with some agencies moving away from it. A new paper from Brian Taylor …
In working with transportation agencies across the U.S., our team often faces questions about the role of safety in accessibility analysis. While we know the safety and comfort of streets clearly impacts access for people on foot or bicycle, the effects of accessibility on overall safety haven’t been clear. Fortunately, leading experts in both accessibility and traffic safety recently teamed up to answer this question.
“Soft” transportation policy measures can influence a significant reduction in personal car use, according to a new research. Six psychological variables that can affect travel behavior: attitudes; emotions; habits; social, cultural, and moral norms; knowledge and awareness ; and capability and self-efficacy. The results show that interventions that focus on social, cultural, and moral norms have the most significant effect on travel behavior.
Because of the COVID-19 pandemic and subsequent shelter-in-place orders, more Americans are teleworking. This has drastically reduced VMT and air emissions. Policymakers may be tempted to try to encourage teleworking post-COVID-19 in order to keep the traffic down and the air clean. But as we’ve reported before, telework is probably not a great strategy for emissions reduction, due to several rebound effects. Teleworkers tend to live farther from job centers, in lower-density environments, leading to longer, more auto-dependent commutes when they do go into the office, as well as higher levels of non-work VMT.
A new study in the Journal of Planning Education and Research compares the 2017 VMT patterns of Millennials to the 2001 patterns of Generation X. Both groups were at a similar age at the time of the surveys. Previous commentary has proposed that Millennials’ driving patterns would approach those of the previous generation once they aged into child rearing and more fully recovered from the recession of 2008. This study concludes that Millennials are not as likely to drive, even as they reach these traditional milestones.
With overall traffic down due to the COVID-19 pandemic, one highway in Oregon is now moving higher traffic volumes at twice the typical speed, according to an analysis by Joe Cortright at City Observatory. This might seem counterintuitive, but it perfectly illustrates the benefits of managing traffic demand, based on simple traffic engineering principles.
The Oregon Transportation Commission last month approved a revised speed-limit guidance that abandons the long-standing-but-arbitrary 85th percentile rule in many cases. Instead of relying on drivers to set speeds by their behavior, the new guidance provides context-based safe speed ranges for urban and suburban roadways, ranging from 20-25 mph in urban cores to 25-35 mph in more suburban areas. The rule gives leeway for setting limits outside of those ranges. Rationales for exceptions do include observed motorist speeds, but they are based on the slower 50th percentile rather than the 85th.