Modern state DOTs and their engineers are grappling with a different set of challenges than they did in the 20th century. Some are shifting to managing travel demand and limiting vehicle-miles traveled (VMT) to make their systems operate more efficiently. But engineering education programs may not be properly preparing engineers for these new challenges, sometimes leaving them to learn on the job in environments that can be mired in old ways of thinking.
TDM
Transportation disrupted: People adapt to rising prices
Most traffic models and transportation plans assume people’s travel behavior is largely predictable and unchanging. Usually, this means more and more driving year after year, and investments aimed at meeting that rising demand. But the most recent spike in gas prices shows just how quickly people adapt their behavior to even small price cues.
Roads less traveled: the safety surprises of big cities
The most effective way to stay safe on city streets is remarkably simple: drive less. A new report from StreetLight Data suggests that the vehicle miles traveled (VMT) is the single most important factor in determining how safe a city’s streets are for everyone. Risk is not solely caused by bad drivers; daily driving habits and city layouts play a significant role as well. With U.S. crashes resulting in 2.4 million injuries or deaths in 2023, one of the best safety strategies for planners and engineers is to help people spend less time behind the wheel of a car by making walking, biking, and transit easier to use.
Bus lanes make busy roads work better
In almost every urban area, congestion has been rising for years despite expensive efforts to widen roads and add lanes for private vehicles. But a new study shows that when demand is high, repurposing the road space already available can boost system performance without any expansion. Creating dedicated lanes for buses and bikes can optimize space – and failing to do so can start a vicious cycle of congestion.
Caltrans review finds outdated and misunderstood models hinder project analysis
In California, where travel demand models often guide project-level decisions and analysis, a new report finds many are outdated, poorly documented, and ill-suited to the purposes agencies sometimes use them for. Transportation agencies rely on models to forecast traffic and guide billions of dollars in infrastructure investment. Without updates, these tools risk locking in old assumptions about growth and travel behavior rather than helping agencies plan for a more sustainable and efficient future.
California will let agencies pay for housing to offset increased driving
A new California law gives transportation agencies the option to pay into an affordable housing fund to offset the increased travel demand associated with major road projects. The approach could achieve several goals at once: mitigating emissions from highway expansions, creating a new funding stream for affordable housing, and helping more people live in accessible neighborhoods, reducing their transportation costs.
Congestion pricing could be the only path to managing gridlock
Transportation agencies in the U.S. spend billions of dollars each year expanding highways to ease gridlock. Yet commute times have increased 20% over the last 50 years and traffic congestion is still worsening, according to a several reports. New research confirms congestion pricing may be the best path toward any kind of relief. New York’s program, which launched in January amid plenty of controversy, looks like a promising example.
Advanced models can’t replace sound judgment
The investments made by transportation agencies are often guided by increasingly sophisticated models and forecasts, which strive to account for more factors and become more accurate in predicting travel patterns. These improvements, while promising for the future, also highlight the many ways that most agencies’ existing models miss the mark. Values-based decision-making can help agencies achieve the outcomes they have set out in their long-range plans more effectively than relying on models alone.
To reclaim downtowns from traffic, require developers to offer strategies for cutting car use
The dominance of parking has devastated once-vibrant downtowns by turning large areas into uninviting paved spaces that contribute to urban heating and stormwater runoff. It has driven up housing costs, since developers pass on the cost of providing parking to tenants and homebuyers. And it has perpetuated people’s reliance on driving by making walking, biking and public transit far less attractive, even for the shortest trips. Why, then, does the U.S. have so much of it?
Researchers warn traffic studies could face more legal scrutiny
Local governments often rely on traffic impact analyses to review and approve projects, charge impact fees, and ask developers to go above and beyond the basic requirements. These traffic studies, however, are often based on “junk science,” and may not hold up in courts much longer, according to a new Viewpoint article published in the Journal of the American Planning Association.