More and more people are using bikes as their preferred mode of transportation. How do we make city streets safe for the growing number of bikes? CityLab reporter Laura Bliss is here to chat with us about results from a study of crash and street design from 12 cities.

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Show Notes:



Robert: (00:04) From GRIDSMART Technologies, this is POLICYSMART. I’m Robert Johnson. This episode we’re talking about the growing number of people who ride their bicycles to get around and how to make their trip on city streets safe. A new study of crash and street design data from a dozen American cities reveals the problems and points to some concrete solutions. The findings result from the review of 13 years of data compiled by Wesley Marshall and Nicholas Ferenchak from the University of Colorado Denver and the University of New Mexico. Our conversation about the research is with Laura Bliss, West Coast Bureau Chief of City Lab.

Laura: (00:44)This was an unusually comprehensive study. There’s been a lot of research into what kinds of health impacts do we find associated with bike lanes and different kinds of street design kind of formulation. Because if you look at the numbers overall over the last 10 years, we’ve really seen an uptick in the number of people who are dying on the road and that includes in cities and this is kind of where this idea of the Visions Zero movement comes from that this kind of reduced the number of people who are getting killed in traffic collisions or getting injured in traffic collisions to zero. A lot of cities have adopted. And so we basically, this study that Marshall led looked at crash data and street design data from 12 large American cities over the last 13 years. They were, in particular, looking at bike collisions and bike fatalities, not exclusively but, but kind with a of focus on that and kind of just ran a bunch of different tests to understand what it was that made some cities have much higher numbers of fatalities and injuries than others and they were basically testing three different hypotheses about what it is that might be driving those numbers and particularly as they relate to bikes.

Robert: (02:08) Can you tell us what those were?

Laura: (02:10) One is that safety in numbers that makes a city safer for people to bike. And that’s kind of this idea that when you have larger numbers, sort of larger volumes of people moving around on bikes, whether or not there’s a lane for them, simply the fact that there’s more of them makes it safer to actually do that activity because drivers become more aware there are cyclists on the road. You’re more visible. It’s just somehow sort of a safer feeling to do it when you’re in a pack. That’s one. Two is it differences in a city’s socioeconomic or demographic makeup that lower the risks of fatalities for cyclists? For example, you can imagine that if a city had fewer elderly people living in it for whatever reason, then you might imagine that, that that city would actually be less vulnerable to high rates of fatalities on the streets. Right? Because you have an older folk involved person involved in an accident, they might be more likely to, to succumb to injuries that someone who’s younger wouldn’t. Or lastly, is it all about the built environment? So how important are street design elements? Like having lots of intersections that kind of slowed cars down or protected bike lanes to kind of keep crashes from happening in the first place.

Robert: (03:37) The researchers weighed in on those three theories essentially by discounting two of them in the end, you want to walk through what they determined for each one and the same order that you’ve just outlined them.

Laura: (03:52) Yeah, sure. Absolutely. That there’s safety in numbers. So number one, right? Actually had very little, there was very little statistical evidence in their analysis of all these different cities ever over many, many years that the number of cyclists had very much to do with low rates of, of um, fatalities or injuries. And in fact, just the opposite. They actually found that higher rates of cyclists were actually associated with worse rates of severe injuries at least. And just to be clear, they didn’t try to explain their findings. Right? But so kind of take that, take that with a grain of salt, not, they’re not suggesting why that would be, but that is what they found in the data. Socioeconomic and demographic differences did actually seem to play a role. They found that cities with higher shares of white and affluent residents actually had lower rates of deaths and critical harm resulting from collision. And that is pretty consistent with a lot of research. It’s not that white or affluent people are, you know, in any way, naturally less susceptible. But rather there’s a lot of research that suggest neighborhoods that are lower income and dominantly made up of people of color tend to have much more dangerous types of street design, so less sidewalk access, certainly less bike lanes, higher speed limits. And, and these are all factors that we know can also increase the likelihood of really serious collisions occurring. So lastly, what they found, and the really big takeaway from this paper is that bike lanes, including above all these different street design components, they looked at bike lanes, were actually the strongest indicator of the cities that had lower fatality and injury rate. And they found among those handful of big cities, they studied 12 big cities, that were cycle tracks where the most abundant on a citywide basis, they saw fatal crash rates dropped by 44% compared to the average that the injury rates were halved. So that’s pretty significant for cyclist. Right? We know that and maybe not so surprising but it’s, that’s the other thing all by itself, but what they found beyond that was that they weren’t just looking at cyclist injuries and fatalities. They were also looking at other kinds of road users and they actually found that drivers too were getting into fewer serious collision when bicyclist also had these lanes.

Robert: (06:29) I suppose it’s not surprising to say if bikes and other non-motorized forms of transportation have their own lane, everything gets a little bit more orderly, a little safer. Did you expect when you opened this study to find a different conclusion or was it fairly common sense to you after you worked your way through it?

Laura: (06:56) I mean it’s hard to say what I expected. I think, I think I probably had read about the conclusion of the paper before I read it. It wasn’t totally surprising, but it is, it is new. It is certainly a significant finding for the community of people who care about road safety number one. And particularly in light of how, you know, what we, the kinds of battles over bike lanes that we see in cities all over the country and different parts of the world too, right? I mean it’s almost always contentious, right? A new proposal to take away a parking lane is what it usually is a parking lane to make way for bike users, right? Because people are really, really attached to their parking spaces in most places, um, and understandably right parking lanes that, you know, maybe I’ve been there a long time. People sort of tend to develop this, this belief that they’re there for them and, and sort of essential to business and other kinds of things.

Laura: (07:59) And there’s lots of reasons that kind of that and, and even that find, you know, oh actually bike lanes are good for business and they can actually increase traffic flow rather than, you know, continue to kind of clog up the streets by it, by adding more space for cars. It just kind of a whole other tangent we could go down into, but this is quite novel and actually finding not only are bike lanes safe for cyclists, which, which anyone you’ve ever used a bike, I think, could figure out implicitly. They’re also good for drivers. And you know, I think you can kind of think of reasons that might be the case, right? Um, when you have more separation in between a more vulnerable road user just on a bike versus someone who’s going around in a big steel box in their car, there’s going to be just a little bit more implicit safety built into that, that relationship. So I I think, I think it’s really interesting, you know, in terms of how this research might be used to kind of shape debates that are happening locally around what the value of bike lanes are. And it’ll be interesting to see if it changes any, any minds or any kind of perspectives on, on, on their value from the community of people who, who drive and who tend to be more attached to those parking spots that tend to give way for new bike lanes.

Robert: (09:21) Well, according to your reporting, not all street design elements are created equal. You had some folks quoted who had some thoughts about that. Shared lanes are useless, I think was one of the comments that you reported. I’m wondering, I am wondering about painted lanes though, where you know, there isn’t a, a physical barrier separating the bike lane from the vehicle lane, but it’s striped accordingly. Did you find any further on that, on that front that was beneficial or not so much of a help?

Laura: (09:54) Yeah. From the perspective of cyclist safety, it was essentially equally beneficial from the prespective of cyclists to have painted bike lane or a fully separated bike lane, which I think is what you’re talking about, right, with, with the sort of plastic cones or planters, but for drivers in terms of their rates of collision and you know, injury, a involved collision, those protected bike lanes is actually fully separated bike lanes with [inaudible] or planters or, or other kinds of physical fortifications were more protective.

Robert: (10:32) How about in terms of ranking cities in the country where this is happening or isn’t happening? Did you do any work in that area or have you looked at examples that the rest of the country should model?

Laura: (10:49) Yeah, I mean I think we’ve seen Davis, California is like consistently ranked as like the number one biking city in the country and that’s a university town that was built up from the ground up, um, in the 1960s and seventies from a very cyclists first perspective. So I think in sheer rate of protected bike lanes, I think, I think they’re number one. But yeah, a lot of cities are making big headway. Portland is another city that gets called out a lot for being really sort of bike friendly. New York City has added like hundreds of bike lane miles in the last 10 years. That’s become a really radically different place to bike than it used to be. You know, Washington DC is, is up there as well. San Francisco has a pretty high rate of protected bike lanes too. You know, these are all dense cities where there’s also a lot of car traffic. So you know, you know, and not in all cases are we seeing, you know, substantial reductions and, and fatalities and injuries. Although New York City, um, has seen a pretty, pretty good dip in pedestrian fatalities at least. And there are some, some observers who would connect that to some of the kind of like lane separation and, and, um, you know, traffic intersection redesigns that the city has done in, in support of bike lanes to an extent.

Robert: (12:18) Did the researchers, when you spoke to them indicate what their hope was for this finding? Did they say anything about what they were expecting planners to do with this information they’ve managed to pull together and present?

Laura: (12:34) No, I mean, you know, I think these are, these are academic researchers. So you know, I think even from a policy perspective, often academics are somewhat reticent to say that there’s an express purpose, right, to information, um, or, or you know, their, their research findings. But, you know, certainly this is evidence that you know, it is, it is one study. It’s certainly a more thorough and far-reaching study than, than we tend to see in terms of research into perceived benefits or drawbacks of bike lane, um, which often focused on, you know, one or two cities or, or just for a couple of years of data. This is much more substantial, right? It’s 12 cities over 13 years. All that, that is evidence to support planners and, and cities that are trying to make changes in how they orient their streets in support of safer streets. Right? And, and, and, and potentially in supportive their, you know, Vision Zero goals if they have them. Um, and just to, just to reiterate, right, that’s the sort of policy that a lot of cities have adopted that they, they want to bring their fatalities and injuries on the street down to zero within a certain timeframe. So, while I don’t know that the researches themselves have that explicit hope, I would say that just based on the story being up on City Lab, I can tell that a lot of planners and kind of city minded folk have been reading this story with some delight and we’ll see, we’ll see if it enters into a new conversation.

Robert: (14:06) So you’ve had some reaction from people who are actually out doing this work?

Laura: (14:10) It’s been a widely shared. There’s a lot of comments on the story. Yeah. I can’t say. I couldn’t tell you yet that the story itself or the findings or whatever has been out in public forum, you know around a new bike lane or what have you. But it’s certainly a live debate in a lot of different places.

Robert: (14:30) Good. You’ve, uh, you can tell that people are looking at the story which means they’re interested in the information. Maybe they’ll end up using that for justification when they go into propose a change to their plan or an addition to their plan. Reprogramming money or asking for new dollars. Everyone wants the street to be safe. I think motorists and cyclists alike would agree that you know, giving everybody their own space would just make life better for all users. That’s really what this story is about. What this research is about, isn’t it?

Laura: (15:05) Yeah, I think so. I think to our sort of pro-cyclist, pro-bike lane that is what this research is about and I think it’s, it’ll be interesting to see if it, if it changes any minds. If it gets, if it gets used in debates over bike lane, you know, where there’s active battles happening. You know, Baltimore is the one that was sort of called out in the story, which has had a lot of controversy over it’s cycling a lot of different angles. Right now they’re actually tearing out a couple of lanes that were only recently put in because there’s been so much backlash from people who miss their parking spots and, and, um, actually from the Fire Department who complained that the streets have now become too narrow for their trucks to pass through. A controversy there. But you know, I think, I think it will be interesting to see if this research comes up and say, you know, sort of say hey drivers, you know, you too are, are potentially benefiting from this kind of infrastructure. I think the sort of parking, parking spot versus bike lane debate tends to come from a very emotional place. I think for a lot of people. So I don’t know that kind of research finding is gonna rock the boat so substantially in another direction. But it’s certainly an interesting finding.

Robert: (16:24) Links to the study and Laura’s reporting on this and other transportation topics can be found in the show notes for this episode. That does it for this edition of POLICYSMART. If you like our show, be sure to share it with your colleagues. You can also leave us a rating and a review. Those are helpful and much appreciated. If you have a question or comment, email us at POLICYSMART is a podcast production of GRIDSMART Technologies. Until next time, I’m Robert Johnson. We’ll see you then.

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