Curb of Death

December 27, 2016    

What an exciting year it’s been for bike infrastructure. One thing seen about town was an experimental raised bike lane with several different curb treatments including; gradual slope, steeper slope, and a vertical curb.

The SFMTA chose the vertical curb option, in part because it was preferred by people who answered an online survey. The full report here.

“we recommend a bikeway design that’s level with the sidewalk (similar to that in option C), has a vertical curb (as used in option D) and includes buffer areas between both the traffic lane and the sidewalk”

Unfortunately, here’s option D in action:

As anyone who has ever walked downtown has seen, even a tall curb is no barrier for a truck, but even a short curb is dangerous for cyclists. Lest we forget, advocacy by the SFBC is the reason those big metal road construction plates get sloping asphalt patches around them, and they’re only two inches high.

So what do we end up with when option D is implemented on a busy bike corridor? I’m worried that it looks a lot like riding on the sidewalk. That’s not safe for pedestrians or bicyclists.

Imagine what will happen when a pack of 20mph bike commuters comes up behind a group of tourists on rental bikes or a truck that was able to climb the curb and park in the bike lane.

Half the commuters go to the left, and somebody falls off the non mountable curb into the street. The other half pass on the right, and because the bike path is level with the sidewalk, they spread out onto it, mixing with pedestrians. Then the ones who haven’t crashed yet get right hooked at the intersection because you can’t merge with traffic before getting to the intersection if there’s a curb in the way.

It’s a radical idea, but maybe, just maybe, the answer isn’t separated bike facilities everywhere, all the time, even if it is the most popular choice on internet surveys. Maybe the answer is to slow motor vehicle traffic down to bicycle speeds (which, incidentally are also sub fatal for everyone), so that bikes and cars can coexist.