How reliable are traffic forecasts?

As reliant on traffic forecasts as transportation agencies are to plan and design road projects, those forecasts are rarely evaluated to see how well they held up after project implementation. A massive new study, outlined in a recent NCHRP report, fills that gap. It compares traffic forecasts from 1,291 projects that opened since 1970 to actual traffic counts. Only 10 percent of the projects opened before 2003.

How might travelers behave with privately-owned AVs?

In many ways, we can only speculate about a future with autonomous vehicles on the road. The effects on vehicle miles traveled are expected to be very different if AVs are privately owned versus shared. A recent post on Jalopnick reviews a study published in 2018, that focuses on the question of individual ownership. The results point to a potential worst-case-scenario; a catastrophic increase in VMT that could occur with the introduction of privately-owned AVs.

Transit-oriented development, VMT, and induced gentrification

Many cities are pursuing transit-oriented development as a strategy to decrease regional vehicle miles traveled. But as TOD has become popular with higher-income residents, low-income residents can be pushed out, complicating that goal. A recent study in California looked at travel patterns of both the new residents of transit-oriented neighborhoods, as well as the households displaced due to gentrification.

Growth near transit is key to connecting smaller cities, SSTI finds

A new study by SSTI and the Traffic Operations and Safety Lab at UW-Madison provides a partial roadmap to the future for transit in smaller cities. The study gave Eau Claire, Wisconsin—a city nearing 70,000 people—a look into emerging transit technologies and insight on their residents’ perspectives toward transit. SSTI also laid out a dozen future scenarios, evaluating each one using accessibility metrics.

More highways, more congestion

In pursuit of congestion relief, the United States added 63 percent more urban freeway lane-miles between 1990 and 2017. That rate far outstripped the 46 percent growth in urban population. It didn’t work. As widely reported last month, the Texas Transportation Institute’s Urban Mobility Report has returned after a five-year hiatus.

New mindset needed to address congestion, says MassDOT

A new report from the Massachusetts DOT dives into the state’s growing traffic congestion to understand the causes and potential solutions. It points to the rapid outward growth around Boston as one of the main causes, and suggests the current situation calls for bold new solutions aimed at connecting people and places while managing demand, rather than simply keeping roads moving.

Use of multimodal accessibility metrics in project prioritization and investment

The Accessibility Observatory at the University of Minnesota recently released a one-of-a-kind report that ranks the country’s 50 largest metropolitan areas (by population) according to accessibility to jobs via bicycle. The report is a product of a multi-year study, where the researchers analyzed land use and transportation systems to measure accessibility to destinations via different modes. The researchers also incorporated traffic stress and bicycle comfort in measuring accessibility.

A new technique to identify deteriorating infrastructure using satellite data

With budgets that tend to favor new construction, many DOTs are finding it necessary to prioritize the most urgent repairs. But infrastructure decay is not always easily visible. And deferred or inadequate maintenance may occasionally have catastrophic consequences for U.S. bridges, 40 percent of which are at least 50 years old, and 9.1 percent of which are considered structurally deficient. A new remote sensing methodology may make the job of decay detection easier, and possibly more accurate.

Spending smarter: lessons and opportunities for state DOTs

Two states that are changing how transportation investments are prioritized were featured recently on an SSTI webinar. Virginia just funded a third round of projects under its Smart Scale program, while Hawaii piloted its own SmartTRAC program with help from SSTI and Smart Growth America. SSTI will soon be launching a new project to learn from these past experiences and guide future programs, and we invite interested agencies to reach out.