On Tuesday Arlington County activated a bike-only signal in the Rosslyn area of the Custis Trail at the corner of N. Oak Street and Lee Highway.

This is one of the several intersections on the trail’s “Rosslyn Hill” section, which is definitely the most dangerous section of the Custis Trail.  Numerous cyclists and drivers have collided at some of the section’s crossings in the past.

Bike signal at N. Oak Street looking west along Lee Highway.

This crossing already had a walk/don’t-walk pedestrian signal, which would inform cyclists about the status of the cross-traffic. Since right turns are prohibited on red, cars waiting on Oak Street will not create a conflict when the bike signal is green and the pedestrian signal is in the walk mode.

Cyclists need to watch for right-turning traffic from Lee Highway onto Oak. Although these cars are supposed to yield to bikes and pedestrian in the crosswalk, cyclists should double-check.

The above photo shows the bike signal still green while the pedestrian signal is flashing “don’t walk” with 3 seconds left. Since bikes can cross much faster than pedestrians, this makes sense. There is a brief yellow bike signal that illuminates for 2-3 seconds before changing to red.

I did not observe bicycle behavior at this intersection with the new signal. The signal is green for much more of the time than it is red, probably 75% of the time. Most of the time cyclists will be able to proceed through this intersection without pause. It will be interesting to see how cyclists behave with this new signal: if they will treat it like a car would treat a traffic signal or more like an “Idaho stop.”

It’s great that Arlington continues to work to improve the cycling environment. Hopefully this new signal will increase safety and awareness.

Steve Offutt has been working at the confluence of business and environment for almost 20 years, with experience in climate change solutions, green building, business-government partnerships, transportation demand management, and more. He lives in Arlington with his wife and two children and is a cyclist, pedestrian, transit rider and driver.