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This bike lane might be useful for filtering when the circle becomes jammed with traffic, but otherwise it seems unnecessarily dangerous. If I understand this design, bicyclists would be safer using the general lane.

Cyclists in this curb lane will have to deal with vehicles coming and going unpredictably at every entrance/exit, pedestrians stepping off curbs without looking, etc. All to avoid sharing lanes with vehicles that shouldn't be going any faster than the bikes here anyway.

The bike lanes will presumably serve as traffic calming, which will make it more likely that motor vehicles are not going too fast there. They may also ease entry of cyclists (those who choose to use the lanes) into the circle, since merging into general travel lanes in a traffic circle can be difficult. I have never used a PBL in a traffic circle, but have found the conventional lanes at the traffic circle at the end of 34th street in South Fairlington pretty useful, and have found many other traffic circles quite stressful.


Do you really think my son would be safer biking in the general traffic lane?

It depends on your son, I suppose. I presume you consider the general traffic lane to be unsafe. But do you think your son will actually be safe using the PBL in this design?

Here is my hypothesis: for any bike lane design, there exists a certain critical cycling speed above which a person is safer riding in the general traffic lane and below which a person is safer riding in the PBL. Since that critical speed depends on road design / vehicle turn frequencies / etc., it will change from one location to the next. Just a wild guess, but I'd be surprised if the critical cycling speed for the design shown here were any higher than 5 MPH. There are too many turn opportunities; drivers eying road signs to identify their exit will often fail to notice curb-hugging cyclists. Both approaches to Crittenden are particularly egregious: PBL riders will be emerging from behind stopped buses.

Safe use of this PBL, even at low speed, will require an extremely aware and hyper-alert rider.


Four years ago I lived in Fairlington, two blocks away from that very circle. I always took the lane well in advance of the circle. During my time there, I did observe a few awkward interactions (potential right hooks) between drivers and riders who were using the circle's bike lanes. I have never heard of anyone being hit there, but I would not have been at all comfortable using the bike lanes around that circle.

I don't know what Fairlington was like before bike lanes, but I imagine their installation helped immensely for traffic calming. Which of course makes it easier to merge into traffic when necessary. Around the circles themselves though, I would have preferred a narrower roadway with sharrow markings.

"I would have preferred a narrower roadway with sharrow markings."

Assuming they didn't want to physically narrow the roadway (even if it can be done low cost, say with flexposts, it could introduce issues for emergency vehicles) that leaves paint. To say stripe a shoulder, and also stripe a sharrows, would do little for anyone, since many riders would rider the shoulder anyway, and most VCer don't need a sharrows to take a lane. I suppose some might consider it "teaching" less confident riders to take the lane, but I am skeptical that there is a significant effect there, and think drawing more critical mass with a striped bike lane (esp where there is no door zone conflict) is more valuable. I suppose one might think a sharrows also lets drivers know of the right of cyclists to take the lane, but my personal experience is that that does not work for many drivers, and I think a "bike may take full lane sign" would be just as effective.

Regarding safe speed I agree that is key (though not only average speed, but willingness to slow further or stop at bad visibility intersections, or all intersections) It will depend a lot on visibility - I have not studied the plan above to see how well daylighted the intersections.

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