The Way We Design Our Streets Invites Driver Aggression

Last week, as I was going through customs to enter Canada through Toronto, I received a frantic call from my youngest daughter.

“Dad, someone hit our car.”

This is one of the worst possible phone calls to receive, especially when I was so far away without any ability to help. I peppered her with questions—was everyone okay, was the person who hit her injured, did she need assistance—and the story that unfolded was, thankfully, not the worst-case scenario my dad brain had immediately constructed.

My oldest was leaving the dance studio, driving with the younger one in the passenger seat. They left the studio and drove the short route to the highway intersection. There, they sat and waited a considerable time for the fast-moving traffic to present a sufficient gap so as to enter the traffic stream safely. Chloe said “two minutes,” and Stella suggested it was a long time. I’ve been there and am sure it’s true that they were sitting there for a while.

While they were waiting, a motorcycle pulled in behind them. At some point, the driver decided to go around them on the driver’s side of their stationary car. He pounded on the car (“someone hit our car” meant literally his fist or handlebars struck the car), putting a long scratch in it. He then screamed at the girls through the window and, according to them, made gestures that were scary and threatening.

A gap opened up and Chloe pulled out into traffic. The motorcyclist followed them briefly but then used the next intersection to turn and head in the opposite direction, something he was prevented from doing at the right-in, right-out controlled intersection where the incident occurred. Stella snapped a photo and then called me. 

I’m grateful they’re both okay, and, given my initial assumptions, I’m also glad there isn’t a motorcyclist lying dead on the side of the road, having struck their car at high speed while they turned onto the highway. The anxiety and trauma they suffered was real, but small in comparison to the horrific range of outcomes that particular intersection presents. 

I will confess that, after speaking to both girls separately and getting what I confidently believe is an accurate accounting of the events, my first reaction was to want to track down this biker and, ironically, put him in a ditch. That was a bad reaction from me—let’s call it a dad reaction—and I’ve now had time to cool off and let a calmer, more empathetic, reaction develop. 

I’m struck with this question: What set of conditions caused this guy to lose his cool with my daughters? I obviously don’t know what is going on in his life, the personal anxieties that may have put him in a foul or impatient mood that day, and I’m not going to excuse his aggressive and dangerous actions, but I can also observe the very obvious ways the design of this stretch of stroad creates high levels of tension for most everyone that travels it.

Following the trip my daughters took, they pulled out of the dance studio and headed toward the highway. The studio sits on the end of a cul-de-sac and so there is very rarely any traffic conflict. As they head to the highway, everything about the road they are on communicates ease of mobility: excessively wide lanes due to an implausible design assumption of heavy commercial traffic, combined with on-street parking. (This is in an environment where off-street parking is mandated.) The end result is a drag strip. 

The design communicates to all drivers that this is an area where sufficient spacing and buffering provides a huge margin of safety. In other words: We have your back, drivers, so go ahead and drive worry free. There are no stop signs and no impediments to cars quickly flowing at high speeds to the highway intersection 1,200 feet away.

Of course, in communicating this way to drivers, we put everyone at tremendous risk. Not only are there multiple business entrances along this stretch, providing traffic conflicts at random intervals, there is also a major intersection with the frontage road that causes all kinds of dangerous confusion.

The confusion comes from the unclear signals given to drivers. The danger comes from the high speeds this design induces. 

Drivers approaching this intersection from the frontage road are prompted to stop by a sign. Many of these drivers assume, incorrectly, that this intersection is a four-way stop and that all cross traffic will be forced to stop as they have been. Of course, the sign is not a four-way stop, but drivers are humans and humans rarely rely on mere signage to tell them what to do. The human mind looks for clues in the environment and quickly assimilates them into an understanding of the space.

The geometry of this intersection is balanced; there is nothing to signal to drivers waiting on the frontage road that they are on the subservient traffic route. The intersection is wide open, with huge lanes, excessive recovery areas, and curb radii designed for high volumes of heavy commercial traffic. This openness and balance gives the impression that this is a four-way stop. It’s not. 

I’ve personally had many interactions where drivers pull their car out in front of me, expecting me to stop, and I don’t have a stop sign. As Chloe was learning to drive, I’ve talked about this specific intersection with her many times because she drives through it twice when she goes to and from dance. 

You’re going to feel like you can drive fast. Resist that feeling. You’re going to assume that the traffic at this intersection will stay where they are and wait for you. You can’t assume that. 

I’ve primed her to be very cautious, especially at this particular intersection, but it’s not the greatest danger here. After getting past the frontage road, the next step is to approach the highway and merge into traffic.

The intersection here is really simple, giving the driver only one choice: Turn onto the highway. That simplicity belies the complexity, because merging into traffic requires drivers to do something difficult. The driver has to determine the speed of the traffic coming at them, along with their own ability and comfort with acceleration, and then calculate whether there is a sufficient gap for them to enter the traffic stream.

In this location, the judgment is made more difficult by the highway speeds and, particularly at the time of day dance typically takes place, the heavy volume of traffic. The only thing more dangerous than this merging maneuver is the left-hand turn across traffic. 

These kinds of intersections are death traps. Younger drivers often overestimate their own acceleration capacity and misjudge the gap, forcing drivers now behind them to react in ways that create traumatic crashes. Older drivers tend to have difficulty judging speed and distance and underestimate how quickly the traffic will be upon them as they turn out, with the same effect. 

Traffic engineers hate putting in intersections like this, because these are the exact places where the bulk of our fatal and traumatic collisions occur. In deference to those who push the kind of low-value economic development opportunities found at this kind of intersection, traffic engineers have developed an entire body of work that purports to build these intersections safely. This body of work is institutionalized malpractice.

It is impossible to design a safe intersection when safety relies on imperfect humans exercising imperfect decision-making capacity when misjudgment means a high-speed collision. Engineers who pretend this is possible should lose their license, and those who go along with the notion that “driver error” causes crashes are lying to themselves. 

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If a private corporation designed intersections like this for private users, government watchdogs would force them to put warning labels on them: This intersection is known to be a hazard, dangerous to your safety. Repeated use of this intersection will likely result in death or serious injury.

But, because it is in the public realm, we get the low expectations of public policy, trading an acceptable rate of death and attrition for pathetic levels of economic development, all with the veneer of inevitability provided by the blessing of licensed, technical experts.

Again, I’ve talked to my daughter over and over about the need to be abundantly cautious at intersections like this, and this intersection in particular. That caution is a big part of what caused the frustration of the motorcyclist who lost his cool.

What also likely added to his frustration was his expectations based on experience. An aggressive driver —and if we know one thing about this dude, he was aggressive—has their aggression licensed by this design. The wide lanes, recovery areas, and forgiving curves all support, as the default, an aggressive form of driving. Sure, you can consciously dial it back, but you don’t need to. The people who designed this road compensated for that aggression.

And in compensating for aggression, they invite it. The guy on his motorcycle came up behind my daughters having felt the rush of the wind on his face, the clear and open road, a high-performance bike on a high-performance roadway. And then he ran into a cautious little girl, a ninny more committed to prudence than using this gift of engineering to its fullest. 

That rapid shift of expectations made him mad, and he took it out on my kids. We can say that he was wrong (he was), that he’s probably a repressed jerk (probably is), and that he did something that should be socially and morally unacceptable in any society. 

I’m disgusted, but I also recognize how he came by his sense of entitlement. Other than entitlement, what is being communicated to him by this design? Safety? Caution? Prudence? No, we’ll save those messages for a Vision Zero-funded magazine ad or billboard. 

When it comes to road design, we license human aggression. The surprising thing is that we don’t get more of it.

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