The transportation modeling used to predict higher travel speeds after an expansion or widening is often unreliable or inaccurate and fails to account for a well-known rebound effect called induced demand.

This is where people drive more (or more at peak times) when extra capacity is added to a roadway. USDOT recognized this idea in its rulemaking on fuel efficiency standards, assuming people will drive more if they are buying less gas. But they do not acknowledge or provide guidance on how to measure induced demand for roadway widening. In fact, USDOT allows for the increased driving and congestion to be disregarded so that project sponsors can make the time savings benefits (again, largely for drivers coming from distant suburbs) look better while ignoring the increased traffic, congestion and pollution that will be generated by the project.

There is ample evidence indicating that expanding highways induces more driving and ultimately more congestion and emissions, but the current modeling fails to account for this truism. This is why after decades of highway building, congestion has only gotten worse. It has gotten worse in areas with growing populations and shrinking populations. It has gotten worse even as homes, often owned by Black and Brown people, are demolished to make room for new lanes.

The focus on providing the driver the ability to move faster, many jurisdictions and transportation agencies require a buffer area on the side of the road called a “clear zone” so that when a driver loses control and runs off the road there is space to accommodate them.

But engineers will make deliberate decisions to put people walking in this so-called clear zone. In the exact same area where (an often substandard) sidewalk exists for people to walk, road design standards emphasize setting buildings back from the road and designing utility poles and stop signs that shear off or give way in a crash so that people in vehicles will be less likely to be harmed. Instead of slowing vehicle traffic to eliminate the need for this clear zone, jurisdictions and agencies redirect the risk away from drivers and toward all of the people outside of a car.

The nonsensical way we set speed limits also favors the perceived convenience of those inside a vehicle and leads to hostility for travelers outside of a vehicle. Agencies design roads to accommodate driver error (eg, wider lanes so that a driver can go fast comfortably), which usually sends the message to drivers that they are supposed to drive faster. Then agencies observe the speed that drivers choose and set the speed limit at the 85th percentile, the point at which most people would drive at or below the limit. The faster people go, the higher the speed limit.

Transportation agencies are primed by existing policies as well as political pressures to respond to congestion primarily by widening and building new roads. These pressures also create disincentives to put anything in place for non- drivers, especially if that infrastructure creates a perception of problems for drivers.

The approach turns city, town, and village roadways into highways. And in doing so, those streets do a poor job of serving local homes and businesses, supporting people moving outside of a car, or reducing fatalities. We are left with a system that favors people traveling through a community over the needs of the people who are living, moving, and working in that community.

This cycle comes with heavy costs.

It leads to unsustainable increases in infrastructure spending from all levels of government, and it raises household expenses through increased transportation costs. It also forces communities already disadvantaged by past highway projects to once again face the social and economic burden of highway expansions in their neighborhoods. All of this means that, by design, many of the accepted transportation policies, standards, manuals, and procedures help create new inequities and perpetuate existing ones.