Transportation policy

“Can you name the truck with four-wheel drive, smells like a steak, and seats 35?” Back in 1998, “The Simpsons” joked about the Canyonero, an SUV so big that they were obviously kidding. At that time, it was preposterous to think anyone would drive something that was “12 yards long, two lanes wide, 65 tons of American Pride.” In 2024, that joke isn’t far from reality. And our reality is one where more pedestrians and bicyclists are getting killed on U.S. streets than at any time in the past 45 years – over 1,000 bicyclists and 7,500 pedestrians in 2022 alone. Vehicle size is a big part of this problem. A recent paper by urban economist Justin Tyndall found that increasing the front-end height of a vehicle by roughly 4 inches (10 centimeters) increases the chance of a pedestrian fatality by 22%. The risk increases by 31% for female pedestrians or those over 65 years, and by 81% for children. It’s hard to argue with physics...

The U.S. has a car-centric culture that is inseparable from the way its communities are built. One striking example is the presence of parking lots and garages. Across the country, parking takes up an estimated 30% of space in cities. Nationwide, there are eight parking spots for every car. 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? For decades, cities have required developers to provide a set number of parking spaces for their tenants or customers. And while many people still rely on parking, the amount required is typically far more than mos...

Less than two weeks after train cars filled with hazardous chemicals derailed in Ohio and caught fire, a truck carrying nitric acid crashed on a major highway outside Tucson, Arizona, killing the driver and releasing toxic chemicals into the air. The Arizona hazmat disaster shut down Interstate 10, a major cross-country highway, and forced evacuations in surrounding neighborhoods. But the highway crash didn’t draw national attention the way the train derailment did, or trigger a flood of calls for more trucking regulation like the U.S. is seeing for train regulation. Truck crashes tend to be local and less dramatic than a pile of derailed train cars on fire, even if they’re deadlier. In fact, federal data shows that rail has had far fewer incidents, deaths and damage when moving hazardous materials in the U.S. than trucks. After the train derailment and fire in East Palestine, Ohio, on Feb. 3, 2023, the U.S. EPA tested ove...

The race to decarbonize passenger cars and light-duty trucks in the U.S. is accelerating. Battery electric vehicles accounted for almost 6% of all new vehicle sales in 2022, up from close to 3% in 2021, and demand is outstripping supply, even as manufacturers roll out new models and designs. The Biden administration is spending billions of dollars to build out EV charging networks and providing incentives for purchasing new and used EVs. This shift offers big economic and environmental benefits, but they’re not spread equitably. People who bear the most burdens in our current transportation systems often receive the fewest benefits, and are least able to change their situations. I study the future of clean transportation and energy, and my research analyzes equity considerations in the design of these systems. As my colleagues and I see it, an equitable transition will require thinking broadly about all transportation users and their needs – especially those who are...

The Biden administration is using tax credits, regulations and federal investments to shift drivers toward electric vehicles. But drivers will make the switch only if they are confident they can find reliable charging when and where they need it. Over the past four years, the number of public charging ports across the U.S. has doubled. As of August 2024, the nation had 192,000 publicly available charging ports and was adding about 1,000 public chargers weekly. Infrastructure rarely expands at such a fast rate. Agencies are allocating billions of dollars authorized through the 2021 Bipartisan Infrastructure Law for building charging infrastructure. This expansion is making long-distance EV travel more practical. It also makes EV ownership more feasible for people who can’t charge at home, such as some apartment dwellers. Charging technology is also improving. Speeds are now reaching up to 350 kilowatts – fast enough to charge a standard electric car in less than 1...