Cycle Tracks: What About the Intersections?Posted by Nick in Advocate's Toolbox, Infrastructure, Thoughts on September 17th, 2013 – 4 Comments
The following post is about cycle track design, featuring information and details pulled from the NACTO Urban Bikeway Design Guide, Dutch CROW Design Manual for Bicycle Traffic, Ireland’s National Cycling Manual and David Hembrow’s blog A View From the Cycle Path. The ideas expressed here are my own do not reflect an endorsement by AROW, AROW members, nor my employer.
Bad cycle tracks are bad, but great cycle tracks can be amazing. One place cycle tracks fail the most? Intersections. Concern about intersection safety is one of the most common reasons for cycle track opposition from people who ride bikes today. The following post aims to show that a cycle track can be designed so that people are just as visible as in a bike lane.
No Parking Cycle Tracks
This isn’t a specific treatment for intersections as much as it is a type of cycle track. On streets without parking, a cycle track is as visible as would be a curbside bike lane. Riders are protected by the raised curb, but nothing gets in the way of clear visibility. Stretches of the Cully Blvd cycle track are configured without parking.
The Bend In
The principle is simple: move people riding toward the center of the roadway to the location they would be if they were in a bike lane. Do this early enough before an intersection to ensure visibility by drivers.
This design is disliked by bicyclists if it is configured at every intersection in an area with short blocks because it causes excessive weaving back and forth. The cycle track on Cully Blvd uses this design, and I have heard many comments expressing dislike for the treatment.
The Bend Out
A less intuitive solution, this “bend out” design is the opposite design from a “bend in.” This design shifts the cycle track away from the main roadway in order to separate conflicts into an area outside of the main intersection. Car drivers first turn right around the corner, then they stop for bicyclists in an space large enough to be outside of the flow of traffic.
Dutch design manual recommend this on high-speed roads in less developed areas, where more space may be available. This is less likely to be an appropriate solution in the middle of a city.
The Clear Zone
It is also possible to overcome visibility issues by prohibiting parking in advance of the intersection or driveway, and ensuring the area is clear of other obstacles. This may be done with paint, or with curb extensions.
Also key to this concept is to design the turn for slow speeds. The slower the turning speed, the more time bicyclists are visible and the more time everyone has to react.
The Mixing Zone
Seen on the NE Multnomah St Cycle Track, a mixing zone requires right turning cars to enter the cycle track space to make their turn. Car drivers must wait to merge, and the shared lane is designed to be too narrow for side-by-side riding.
This design is criticized for being a stressful condition in an otherwise low-stress route, but sometimes is the only way to retain a right turn only lane in constrained spaces.
The Raised Crossing
Raised bikeway crossings give a clear message that bicyclists have priority at driveways and intersections. Legally, cars turning right must yield to a bicyclist going straight through (the same rules as if there were a bike lane) and this design reinforces the law with physical infrastructure.
Maintain the cycle track and sidewalk raised as they pass through the intersection. Cars will need to mount over the cycle track and sidewalk, similar to entering a driveway. When designed correctly, drivers will be going very slow when turning.
Traffic signals can also be used to manage conflicts. Right turning cars can have a red light, while bicyclists going straight receive a green light. A configuration like this is installed at NE Broadway & Williams, where a bike lane conflicts with right turn lanes.
What do you think?
Are these designs worth consideration? Do they help overcome some concerns about cycle tracks? Post your comments, questions and suggestions below. If cycle tracks are our future, lets make sure we get them right.