This comes after decades of steady decline, causing many to wonder: What the hell is going on?

Brian Potter of Construction Physics recently tried to answer this question, here. Perhaps the two most common theories are that (1) bigger cars have become more popular (and bigger cars are more deadly to pedestrians), and (2) people are increasingly distracted by smartphones.

In his view, the SUV theory is maybe supportable, but the evidence is mixed. Pedestrian deaths involving smaller cars like Honda Civics are also up substantially. So it doesn’t seem to be just that.

As for the smartphone theory, Potter cites data showing that traffic accidents rarely report “distracted” driving. I call bullshit. I suspect it's because drivers don’t want to admit they were scrolling through TikTok; but even then, it doesn’t appear to be the clear cause. Smartphones are global, and yet this surge in pedestrian deaths is a uniquely American problem (based on other data from Potter).

So what is it?

My view — and this isn’t mentioned in the article — is that built form must be a factor. Much of it comes down to how we design our cities. Intuitively, this makes sense to me. But there’s also data to support it. First, if we look at pedestrian deaths per capita, there’s a clear bias toward the South and West, both of which tend to have more car-oriented urban patterns compared to the older cities in the North.

Second, if you drill down into specific urban environments — including those adopting strong Vision Zero policies — you’ll see that local trends don’t always match what we’re seeing nationally or even at the state level. For example, in recent years, cities like New York have become much safer for pedestrians:

New York City continues to defy national trends around pedestrian deaths, which are currently at a four-decade high nationwide. Traffic fatalities were down in four of the five major travel modes the DOT tracks. Compared to 2013—the last year before implementation of Vision Zero—New York City traffic deaths have dropped by 14.7%, from 299 that year. Pedestrian deaths have decreased by 35.9% compared to 2013 figures. Cyclist fatalities were also down for the third straight year (17 in 2022, down from a 20-year high of 28 in 2019), declining even as bicycle ridership has soared in recent years.

So my simple theory is this: Human-scaled spaces that are designed around pedestrians, rather than cars, are less likely to kill pedestrians.

At the same time, I do think we’ll see pedestrian deaths naturally come down in the US as autonomous vehicles become more widespread. AVs are already better — or at least safer — drivers than humans, and that will help. None of us should be driving cars anymore if you're just looking at the safety data. But I don’t see that as a good reason not to create more human-scaled spaces. They offer us much more than just safety.

Diagrams: Construction Physics

This comes after decades of steady decline, causing many to wonder: What the hell is going on?

Brian Potter of Construction Physics recently tried to answer this question, here. Perhaps the two most common theories are that (1) bigger cars have become more popular (and bigger cars are more deadly to pedestrians), and (2) people are increasingly distracted by smartphones.

In his view, the SUV theory is maybe supportable, but the evidence is mixed. Pedestrian deaths involving smaller cars like Honda Civics are also up substantially. So it doesn’t seem to be just that.

As for the smartphone theory, Potter cites data showing that traffic accidents rarely report “distracted” driving. I call bullshit. I suspect it's because drivers don’t want to admit they were scrolling through TikTok; but even then, it doesn’t appear to be the clear cause. Smartphones are global, and yet this surge in pedestrian deaths is a uniquely American problem (based on other data from Potter).

So what is it?

My view — and this isn’t mentioned in the article — is that built form must be a factor. Much of it comes down to how we design our cities. Intuitively, this makes sense to me. But there’s also data to support it. First, if we look at pedestrian deaths per capita, there’s a clear bias toward the South and West, both of which tend to have more car-oriented urban patterns compared to the older cities in the North.

Second, if you drill down into specific urban environments — including those adopting strong Vision Zero policies — you’ll see that local trends don’t always match what we’re seeing nationally or even at the state level. For example, in recent years, cities like New York have become much safer for pedestrians:

New York City continues to defy national trends around pedestrian deaths, which are currently at a four-decade high nationwide. Traffic fatalities were down in four of the five major travel modes the DOT tracks. Compared to 2013—the last year before implementation of Vision Zero—New York City traffic deaths have dropped by 14.7%, from 299 that year. Pedestrian deaths have decreased by 35.9% compared to 2013 figures. Cyclist fatalities were also down for the third straight year (17 in 2022, down from a 20-year high of 28 in 2019), declining even as bicycle ridership has soared in recent years.

So my simple theory is this: Human-scaled spaces that are designed around pedestrians, rather than cars, are less likely to kill pedestrians.

At the same time, I do think we’ll see pedestrian deaths naturally come down in the US as autonomous vehicles become more widespread. AVs are already better — or at least safer — drivers than humans, and that will help. None of us should be driving cars anymore if you're just looking at the safety data. But I don’t see that as a good reason not to create more human-scaled spaces. They offer us much more than just safety.

Diagrams: Construction Physics

According to Potter, there are, perhaps not surprisingly, three main drivers of demand: beaches, lakes, and ski resorts. This is why if you drill down into Florida — which has the highest absolute number of vacation homes in the US at over 800k — you'll see that these homes are not evenly distributed across the state. They're on the coasts, and to a lesser extent inland near places like Disney World.

Also noteworthy is the fact that these census tracts tend to match up nicely with the location of ski resorts. Here's the same map of the US but with ski resorts overlaid:

And here's a close up of Salt Lake City and Park City, because, I love Park City:

As of Q1-2025, the US had over 147 million homes, and somewhere around 4.3 million of these were seasonal or vacation homes. If you'd like to better understand where these are and the trends surrounding them, I recommend you check out Potter's post.

Maps via Construction Physics; cover photo by Joe Ol on Unsplash

At least two things can be readily gleaned from the data in his post. Number one, US Interstates tend to be pretty good. More than 80% of the mileage is classified as "good" or "very good." Non-interstate roads are, on the other hand, much poorer. And in every single case, urban roads are worse than rural roads, presumably because of their higher traffic volumes. Number two, there doesn't seem to be much of a correlation between climate and road quality. Intuitively, one would think that freeze-thaw cycles and road salt would give cold cities the worst roads, but that is not actually the case.

Los Angeles sucks the most.

Cover photo by Thaddaeus Lim on Unsplash

According to Potter, there are, perhaps not surprisingly, three main drivers of demand: beaches, lakes, and ski resorts. This is why if you drill down into Florida — which has the highest absolute number of vacation homes in the US at over 800k — you'll see that these homes are not evenly distributed across the state. They're on the coasts, and to a lesser extent inland near places like Disney World.

Also noteworthy is the fact that these census tracts tend to match up nicely with the location of ski resorts. Here's the same map of the US but with ski resorts overlaid:

And here's a close up of Salt Lake City and Park City, because, I love Park City:

As of Q1-2025, the US had over 147 million homes, and somewhere around 4.3 million of these were seasonal or vacation homes. If you'd like to better understand where these are and the trends surrounding them, I recommend you check out Potter's post.

Maps via Construction Physics; cover photo by Joe Ol on Unsplash

At least two things can be readily gleaned from the data in his post. Number one, US Interstates tend to be pretty good. More than 80% of the mileage is classified as "good" or "very good." Non-interstate roads are, on the other hand, much poorer. And in every single case, urban roads are worse than rural roads, presumably because of their higher traffic volumes. Number two, there doesn't seem to be much of a correlation between climate and road quality. Intuitively, one would think that freeze-thaw cycles and road salt would give cold cities the worst roads, but that is not actually the case.

Los Angeles sucks the most.

Cover photo by Thaddaeus Lim on Unsplash

Share Dialog

Share Dialog