Lessons from the 2013 Minneapolis Bicycle Crash Report

The Minneapolis Department of Public Works released a new report this week, an in depth analysis of the city's bicycle crash reports from the last ten years. The results are interesting and useful, offering some more insight into why and where accidents happen and offering some suggestions on how to begin increasing bicycle safety. In some ways, this is nothing new. Safety has been the #1 concern of bicycle planners and advocates for at least 40 years, and cities are continually struggling with the same kinds of questions. Often they revolve around proper design treatments, and the old 70s debates over on- v. off-street bicycling paths are a good example of what these arguments might look like. But these days, cities have largely moved past those kinds of petty arguments. These days, issue is rarely one of a lack of knowledge about how to build good bicycle infrastructure. Rather, the issue is generating the right kind of political and institutional consensus.

That's where reports like this come in handy. The Minneapolis report is as good a study of crash data as you're ever likely to see in this country, and the city should be commended for doing such a thorough job. Not only did they collect and analyze an entire decade of bicycle accidents, they went 'in depth' with a few years of data, moving beyond the often vague police accident reports to include things like "dooring" (which don't have a proper code). They geo-coded all the information into a few fabulous maps, and they placed the whole study into a larger context of the history of accident statistics. Finally, the report comes with a few key suggestions that don't rely on blaming any particular group of people. It's tremendous work that should be the envy of public works departments across the country.

While a lot of the study seems a bit predictable (e.g. that bicyclists and drivers are both at fault in crashes), there were a few things that jumped out at me as I reading through the 30-page .pdf the other day.

Here are my highlights:

#1 Stats will always be inadequate

A friend of mine was bicycling along Riverside Avenue a year or so ago, and was in a terrible crash with a turning truck that didn't see her. The truck completely destroyed her bicycle, and she narrowly missed having her legs crushed. After the incident, the driver stopped and offered to buy her a new bicycle. She didn't go to the hospital, and got a new bike out of the deal, but was absolutely terrified and easily could have been killed. The key thing about the crash: there wasn't an accident report

The Minneapolis study rightly points out that accurate information on bicycle crashes is impossible to come by. The report links to a few studies that suggest that around half of all bicycle accidents go unreported. In fact, it's really difficult to figure out exactly how many accidents might or might not be unreported. (Would it be one of Rumsfeld's "known unknowns," or would it be an "unknown unknown"?) Often, bicyclists won't go to the hospital, or the driver and bicyclist will settle the matter on the spot, without calling the police.

I'd go so far as to say that many more than half of bicycle accidents or incidents are unreported. For every crash in this study, there is likely one crash that resulted in injuries, and two to four incidents that resulted in terrifying the living crap out of someone on a bicycle.


#2 Hit and runs are common

The study points out that 21% of the crashes in the study were hit-and-runs, where the car driver didn't stop. I'd be willing to extend the logic from Point #1 (above), that many close shave incidents also involve people who didn't stop.

The point here is that bicyclists often have to deal with these dangerous conditions completely on their own, and that they're vulnerable in a few different ways. Which brings me to...


#3 Bicyclists suffer all the injuries

Probably the single most one-sided part of the bicyclist-driver relationship is that bicyclists are the ones that suffer all the injuries. In fact, check out this snippet from the study:

Detailed analysis of 800 crash reports from 2006-2008 found that when an injury was sustained, it was always the bicyclist. Motorists sustained injuries in no crashes.

Often, when talking about urban bicycling, arguments devolve into "bike vs. car" diatribes, with each group pointing out the other's supposed misdeeds.  That might be some validity to this kind of balanced framing, but it's worth remembering that only one side of this equation has any physical vulnerability. Only one side is paying the physical cost. It's the exact opposite of an equal relationship.


#4 There's safety in numbers

It's long been a truism in nonmotorized transportation planning that safety improves dramatically as the overall number of bicyclists and pedestrians rise. Well, this seems to hold true for Minneapolis over the last decade, and is one of the most hope-inspiring pieces of the bicycling puzzle. This report includes a nice chart which outlines the relationship:

What this suggests to me is that bicycle advocates should focus their efforts on increasing the total number of cyclists. In a way, safety issues will take care of themselves once we begin to increase the overall awareness and frequency of bicycling in the Twin Cities.


#5 The city's antiquated one-way street pairings are very dangerous

That said, certain streets are very dangerous and should be addressed immediately. Probably the most useful part of this study is the map of the city's trouble spots. (See the top of this post.) The report shows shows the most dangerous places, and much of the information isn't that surprising. (See below.) The worst places are intersections, and particularly intersections of the 4-lane arterial roads running through the city.

But the city went beyond this simple quantitative analysis, and correlated the accident count with their model of average daily bicycle traffic. (Note: most cities don't even have a model of average daily bicycle traffic, nevermind interesting spatial math.) These results show that certain road designs are far more dangerous than others. Certain designs have low overall bicycle traffic counts, but high rates of accidents.

Here's the chart:

As you can see, the city's old one-way street pairings (26th and 28th Streets in South Minneapolis) have a terrible rate of crashes per cyclist mile traveled. (I'd wager that this information could serve as a proxy for pedestrian accidents, as well.) If the city wanted to increase safety overnight, they'd begin converting these street parings (as well as 35th and 36th, University and SE 4th) into proper two-way streets right away. This is something I've suggested before. High-speed one-way streets simply should not be running through dense residential urban areas.


#6 Franklin Avenue desperately needs traffic calming and bike lanes

The final takeaway is something that shouldn't surprise anyone who's ridden a bicycle in South Minneapolis. Franklin Avenue is the #1 problem street in the city, and needs to be fixed right away. Franklin "wins" four of the top ten spots on the coveted "top crash intersection" list. (I'd like to thank the academy... I couldn't have done it without all the distracted drivers who have been speeding for years through one of our city's poorest neighborhoods...)

Luckily, the Minneapolis Bicycle Coalition is working on the problem. Hennepin County has plans for doing something, but I still haven't heard what the final decision is likely to be. Hopefully, this report can push them in the right direction.

[Two suggestions for how to more safely re-design Franklin Avenue. Neither one is perfect.]