Tuesday, November 6

Thoughts on Sharing the Road

On my way home from work today, I snapped this shot of some new "sharrows" that have been painted on Third street here in Missoula. The intent of sharrows is both to help motorists be more aware of the presence of bicycles, and to help cyclists position themselves in the safest part of the street. The Christian Science Monitor ran a helpful story on the U.S. origin of sharrows in Colorado and some of the controversies surrounding them. Today's Missoulian reported on the new sharrows on Third street. Hopefully, they'll work.

It's not hard to pick up on some tension lately between cyclists and motorists around here. Columnist Bob Wire vented on his experience with irresponsible bicycle riders in an article entitled, "Get your Bike of the Sidewalk, Moron." The article unleashed a flood of comments on the New West site as if dangerously high levels of pent-up road rage were finally given a forum for expression. Ah, the blogging catharsis. Everyone has a story about how they were wronged in some way or another.

Considering that two very different vehicles with very different infrastructure needs share the same roads, it's no wonder that these interests clash. Add to that tension whatever cultural symbols and ethical assumptions may be attached to bicyclists and, say, SUV drivers. Then throw in the fact that commuters are naturally ornery, and you've got a perfect storm.

Sure. Everyone should respect each other, follow the law, and so on, but we have to remember that this bike/car balance is hardly symmetrical. Cars can (and do) kill cyclists, while bicycles can (and do) only dent cars. I ride in traffic, but just one aggressive and impatient driver can make the sidewalk look like an attractive alternative.

Also, since automobiles are currently the dominant form of transportation, roadways and traffic laws are understandably designed around their purposes. Traffic engineers have long been aware that good laws need to be consonant with natural human behavior. For example, the 85th percentile rule dictates that speed limits are most effective when they are set at the speed in which 85% of the drivers will naturally drive. Overly stringent regulations have been shown to be ultimately ineffective because they have such low compliance levels. Take this principle into the design of city street laws, and it makes sense that cyclists will be disproportionately inclined to fudge on some laws. I know plenty of residential stop signs that beg bicyclists to cautiously coast through. The calculations that led to those sign placements were based on the safety of automobiles. I'm not saying cyclists should break the law, but I understand why we do.

Like many people, I'm both a driver and a cyclist. Of course, I want to be respectful and careful in both of these roles, but I recognize the special onus of responsibility that goes with the power I possess when I'm behind the wheel.


Jonathan said...

It seems to me that the 85% rule would be most effective if combined with narrower streets and traffic calming devices. That means 85% of the people would be going at speeds that would allow safe interaction with cyclists.

Daniel Nairn said...

I agree. Even subtle visual obstacles seem to have some effect in helping people to slow down and be more attentive. Roundabouts are the big debate in Missoula. I bike through a few almost everyday, and they really do at least make me feel safer.