Bicycle Safety Guide and Countermeasure Selection System

 

Example of a raised separated bike lane. http://www.pedbikeimages.org/ - Carl Sundstrom


 

 

 

Separated Bike Lanes

Separated bike lanes (also known as cycle tracks) are bicycle facilities that run alongside a roadway separated from automobile traffic by a physical barrier, such as parked cars, bollards, a landscaped buffer, or a curb. A separated bike lane is for bicycle use only and distinct from a sidewalk. Separated bike lanes may be one-way or two-way and can be raised or at street-level. One benefit of separated bike lanes is that many bicyclists feel more comfortable being physically separated from car traffic, potentially attracting new riders. Separated bike lane may also reduce cyclist collisions involving parked cars; they can prevent "doorings" by creating a 3+ foot gap between parked cars and the bicycle travel lane, and also keep cars from parking in a bike lane.

When selecting streets for the installation of a separated bike lane, consider locations with high bicycle traffic; high bicycle stress from high motor vehicle speeds or motor vehicle volumes; or high rates of parking turnover. Two-way separated bike lanes should be considered for locations where they would reduce potential wrong-way riding due to out of direction travel, where there is a high concentration of destinations on one side of the street, or other reasons. Also consider the impact on network traffic operations when retrofitting a separated bike lane as the installation typically results in the loss of a motor vehicle travel lane.

One of the greatest concerns for separated bike lanes is at intersections and driveways, which should be clearly marked through a variety of intersection markings. Separated bike lanes are most effective in locations where there are fewer intersection and driveway conflicts as well as minimal loading/unloading activity. At signalized intersections, experimental bike boxes and bicycle signal heads can also be considered, particularly with two-way cycle tracks.

Purpose

Separated bike lanes can provide an attractive bicycle facility for people with a range of riding abilities through the physical separation from motor vehicle traffic.

Considerations

  • At intersections and driveways, make full use of signing and marking to improve awareness and guidance of the facility through these conflict zones.
  • Ensure good visibility and sight lines at intersections and driveways through the use of no-parking zones and non-intrusive landscaping.
  • Consider bicycle signal heads at signalized intersections to provide Leading Bicycle Intervals or contra-flow phasing.
  • Ensure that the intersection has appropriate detection for bicyclists.
  • The minimum desired width of a separated bike lane is five feet with a minimum buffer width of three feet.
  • Consider maintenance of the separated bike lane in the design; the width should be sufficient for street sweeping and snow removal equipment.

Estimated Cost

Costs will vary depending on the treatment. Interim treatments with paint, planters and vertical delineators are inexpensive; however, costs rise rapidly with more permanent installations that could include vertical curbs, landscaping, green pavement markings, bicycle signals, and other features.

Safety Effects

A summary of studies that have looked at the safety effects of separated bike lane can be found here.

References

To view references for this countermeasure group click here.

Case Studies

Washington, District of Columbia
New York City, New York