I know this blog is about the intersection of science, law and the environment, and it has largely adhered to typical topics that you expect to meet at that intersection. But today I’m excited about a different kind of intersection, specifically a study (long and the first of its kind) of protected bike lane intersections in five U.S. cities. (Cool segue, right?)

If you ride a bike, like I sometimes do, you know that the risky part of your ride is the intersection. Right hooks. Merging cars. Left turns. Left turns in traffic behind big cars that obscure you until it is (almost) too late – I had that experience this morning, but everyone was attentive and no one was hurt. Protected bike lanes, at least in my experience, don’t take away the conflict, but they can reduce it. And, significantly, they can improve comfort levels with bike riding, which, in turn, will encourage more people to ride, leading to improved safety, for both cyclists and pedestrians. It’s a fun relationship.

The study, completed in Austin, Chicago, Portland, San Francisco, and Washington D.C., involves the analysis of more than 150 hours of videos of intersections, capturing almost 17,000 bicyclists and almost 20,000 merging and turning vehicles, as well as surveys of intercepted (by the interviewers, I gather) bicyclists and nearby residents. It’s a treasure trove of information that will be digested by smart folks who study, talk, and write about multimodal uses (similar to this article), and, I hope, by civil engineers and traffic planners who design bike infrastructure. It arrives at some expected conclusions, like protected bike lanes increase ridership (significantly, among new riders), but I think its most important contribution to will be its conclusions about successful intersection design.

I love it because I love imagining watching hours of video of all kinds of cyclists, motorists and pedestrians, and how they come together to figure out how to keep everyone safe and moving through our cities; not just lycra-clad weekend warriors, but our children, our grandparents, and everyone in between.

Doug warned you. I like bikes.