What Actually Makes Bike Lanes Safer?

Episode Transcript

Mollie (Host)
Welcome to {Brief}ly Speaking, the SEH podcast that cuts straight to the chase. We tackle big topics in architecture, engineering and construction with quick expert insights. No fluff, just the essentials. Let's dive in. Bike lanes are everywhere right now. Painted lines, buffers, bollards, concrete barriers, you name it. Cities are investing real money into them with the goal of improving safety and getting more people comfortable on their bikes. But not all bike lanes are created equal. Some change behavior and reduce risk. Others mostly check a box. So today we're digging into what actually makes bike lanes safer. What works, what doesn't, and where communities might be spending money without getting the results they expect. Joining me today is Ken Brubaker, a project engineer who spent his career working on transportation systems for both public and private clients. He's led bicycle and pedestrian efforts at the state level and brings a practical on-the-ground perspective to how these systems actually function. So Ken, welcome to {Brief}ly Speaking.

Ken (Guest)
Yeah, thanks for having me.

Mollie (Host)
So when most people think of a bike lane, I think they picture kind of just the painted line on the road. From a safety standpoint, what does that actually accomplish? And on the flip side, what does it not?

Ken (Guest)
Yeah, I think when we think of a traditional bike lane, what it does is it delineates space on the roadway that's meant for cyclists. So it increases awareness that cyclists might be present and then again, kind of gives them their own allotted space to operate within. But what it doesn't do is provide any sort of physical protection, right? So there's nothing stopping anyone from moving their vehicle into a bike lane. So while it increases awareness and provides like an allocated spot on the road, it doesn't provide you any kind of physical protection.

Mollie (Host)
Got it. So these painted lines are probably the easiest and cheapest option. Why do so many communities default to them even when, as you just said, safety can kind of be limited?

Ken (Guest)
Sure. I mean, the easy answer for that is it's probably the easiest thing to do. It's often the low-hanging fruit. It's fairly easy often to kind of re-stripe a roadway, rearrange the line configuration, pavement marking configuration, and create some space that cyclists might operate within. So probably the short answer is it's the easiest thing to accomplish generally.

Mollie (Host)
Makes sense. So then let's step it up one. Talk about buffered bike lanes. On paper, they create more space between the bike and vehicles. But in practice, does that actually improve the safety?

Ken (Guest)
Yeah, it does improve the safety, although it's, I guess maybe you'd say marginal. But any lateral separation or shy distance, any additional distance you can provide, provides kind of an extra level of safety. It creates a little bit more room for error, right, if someone starts to drift out of their travel lane. if you're with a, say, your minimum bike lane of five feet versus a buffered bike lane, you might gain a couple extra feet for that driver to kind of correct their mistake before they potentially hit a cyclist or something like that. So it is safer, but maybe not order of magnitude type of safer. Does that make sense?

Mollie (Host)
Yeah. So Is there a risk that these bike lanes could kind of give a false sense of security then for, I guess, both the bicyclists and the drivers?

Ken (Guest)
Yeah, I don't know about false sense of security. If you've ridden in one of those buffered bike lanes, right, you do feel a little bit safer because every foot you're further away from moving traffic, you're going to kind of feel an additional level of safety, right? So they definitely help. But again, there's no physical protection there generally. If we're talking just a buffered bike lane with pavement markings, right, there's no vertical or physical elements to really slow or stop people from moving into your space. So again, it provides additional comfort and probably a little bit more safety. And everything's based on context of the road, but it's probably not the gold standard of safest bike facility.

Mollie (Host)
Sure, that makes sense. Okay, now we are going to the gold standard of bike facilities here. We're going to talk about protected bike lanes. They're physically separated. They're more expensive. and more complex. So what makes them fundamentally different in terms of safety?

Ken (Guest)
The fundamental difference is what we've been hinting at, right? So when you get to a separated bike lane or protected bike lane, or some people would refer to them as cycle tracks, you get some sort of vertical or physical separation from moving traffic, right? And that can come in a number of different ways. It can be kind of at the lower level, some flexible posts. or something's anchored to pavement that sticks up vertically that people wouldn't necessarily want to drive over, all the way to physical concrete, whether it's barrier or curb or planters, but something that would physically separate you from vehicle traffic. When you get to that level, then you're kind of at the gold standard of quote unquote safest bicycle facilities.

Mollie (Host)
So we kind of ran the spectrum of bike lane options there. I mean, I'm sure there are a couple of other offshoots of those, right? But those are the big three. So when looking at crash data or user behavior, how big is the gap between protected bike lanes and everything else?

Ken (Guest)
We know that protected bike lanes make the road safer for everybody. So they make the road safer for cyclists, obviously, but they also have this odd effect where they make the road safer for motor vehicles as well as pedestrians. I think anytime you can add maybe a sense of order to the roadway and how it should function, that inherently makes things a little bit safer. I do think that hard data on physically separated bike lanes is a little bit difficult to come by at this point just because there aren't that many physically separated bike lanes around the country. As far as widespread data goes, it's five times safer or three times safer. I think a lot depends on the context of the road, the speed of the road, and how well the separated bike lane has been designed and constructed.

Mollie (Host)
Okay, so when communities are looking at these options, I would assume that not every street can or should have a fully protected bike lane, right? Like we don't always need that gold star like you talked about. Where is the right balance between cost and safety? And then how do communities avoid over building in lower risk areas or under building where protection actually matters?

Ken (Guest)
Separated bike lanes are probably the safest and most desirable place for cyclists to ride, especially when you're talking that 8 to 80 group or if you're trying to accommodate children. Separated bike lanes, again, are probably the most desired option, but they're expensive. It's obviously a lot more expensive to construct some sort of physically separated infrastructure versus paint a couple of lines or something on an existing rd. So the cost always comes into play. They also take up more space, generally speaking, so you can get into issues where you have constrained rights of way. It can become difficult to physically fit them into the existing right of way. And so when you start talking about, okay, maybe we need to acquire additional right of way or something, that can also add quite a bit of cost. So when you're deciding where to put these in, I think it's important to look at the context of the roadway. And a couple things jump out immediately that you should be looking at. And one is the surrounding context and like where are you? Maybe everywhere it doesn't make sense to have separated bikeways and I'm thinking rural highways, right? Maybe that is not a situation where it makes sense to have a separated bikeway. And then a couple other things are roadway speed. What speed is the traffic flowing at on that roadway. And so when you start to look at the context and the speed and the size of the road, you can start to determine, okay, maybe if it's a large arterial roadway with five lanes, that's a different story and kind of a neighborhood street that maybe has two lanes and lower traffic and lower speeds, right? So those are some of the things that you would kind of take into consideration when you're trying to decide where should you allocate your resources to have the greatest effect.

Mollie (Host)
And I would imagine that sitting down with someone like you, could help them figure out the puzzle pieces on the paths that they wanted to have their seeing bicyclists take and then what should fit where. Is that how that kind of works? Or walk me through those kind of kickoff meetings processes.

Ken (Guest)
Our team, we often do a lot of that type of planning work to help communities decide what roadways would it make the most sense to have, say, separated bike lanes versus, okay, maybe on a different type of roadway, you could get away with regular bike lanes or even bike boulevards. kind of more shared spaces. And so we'll look at some of those things that we just talked about, right? Like traffic speed, roadway types, land use, and try and do some overlays to say, okay, these are there. And then you can also look existing safety. So your historical crash data and kind of overlay all those things and say, okay, here's the roadways that are really kind of popping where, yeah, you need that higher level facility with more protection that's a little bit safer.

Mollie (Host)
And then in those kind of conversations, Are you trying to help cities or communities avoid any mistakes that are common? What are some of those that you see repeat offenders will say for mistakes where cities or municipalities are trying to just check the bike lane box and get it added because that's what the people are asking for without fully thinking through the safety, the planning, those kind of aspects?

Ken (Guest)
Sometimes communities go with this all or nothing approach. So in other words, if we can't build a Cadillac, we don't want to build anything. And sometimes you don't need a Cadillac, right? Sometimes you can get around just fine in a Toyota Corolla and you can get a lot more Corollas than for the same price you can get a Cadillac, right? So some communities say, well, if we can't build this protected bike lane that is 5 feet wide in each direction and all that kind of stuff, then we're not going to do it. And that's a shame because you can still maybe build a good facility for that roadway type, but it's just not the protected bike lane. I guess the other mistake that we have seen is some communities kind of do the opposite then. They go out and stripe every road with a bike lane when it's completely inappropriate. And so you'll see sometimes 5 or 6 lane arterials that have bike lanes. strike on the outside of them and no one will ride there because they just don't feel safe, right? No one feels safe riding on a road that has 40,000 vehicles a day or something on it. So it's great that they were making an effort, but people are not going to ride if they don't feel safe. So those are the two biggest mistakes I see. Going the all-in approach where we have to have the best for everything we put down and then sometimes, well, no, we're just going to fit in whatever we can, wherever we can.

Mollie (Host)
Yeah, I love that it's not a one-size-fits-all solution. and that you guys can really help define those problem areas so that they get the higher safety there and then maintain costs and have them do the lower safety options in areas where it's just slower speeds not as needed. So I think that's great. Ken, the last question I have for you here is if you could give one piece of advice to a city planning its next bike project, what would it be?

Ken (Guest)
if it's a specific project is maybe hard, but if they're coming up with a bicycle type plan or how do you approach this bike lane question of where to put them, I guess I would say try to build a cohesive network, right? Another mistake we'll see is that cities will build out a really fragmented network for whatever reason, because maybe that's where the opportunities were, those were the streets that got reconstructed. But if you don't have kind of this complete network that people can use to drive around or ride around in this case, it's not super useful, right? You're not going to see the number of cyclists that you want to see or that you hope you would see for your investment. So you got to kind of look at it from a network perspective to help people get from A to B, not just part of the way from A to B. That would be one thing that we would try to encourage too, is like, does this fit into the network? Is this making the most sense? Taking a look at that. And then obviously we have lots of design experience too, so I'm sure there's very specific project level things that we could come up with. Those are more unique to each project.

Mollie (Host)
No, I love that. And I think the network piece that you talked about there makes total sense. And I would imagine the destinations, like where are people going? What are they wanting to get to and then connecting those all plays a part in it. So I think that's great advice. All right, well, as we heard today, Bike lanes aren't a one-size-fits-all situation and not all designs deliver the same level of safety. So the difference between a painted line and true protection isn't just design preference, it's real-world impact on behavior, on comfort, and ultimately on whether people feel safe enough to actually use the infrastructure. Ken, thank you for helping us cut through what works and what doesn't and where the investments can be made and make a real difference. And to everyone listening, if you found this helpful, be sure to follow or subscribe to {Brief}ly Speaking so you won't miss what's next. Thank you.