Applicable Bicycle Lane Design Criteria
Kansas cities have adopted an amended version of the 2017 Standard Traffic Ordinance for Kansas Cities, which states in Art 4, Sec 11 that all traffic control devices shall conform to the state manual and specifications. Kansas statute K.S.A. 8-2003 requires the Secretary of Transportation to adopt a manual for traffic control devices. Transportation Secretary Debra Miller adopted by letter dated December 16, 2011, the Federal Highway Administration (FHWA) 2009 edition of the Manual on Uniform Traffic Control Devices (MUTCD) for use in the State of Kansas, which is the current edition with revisions 1 and 2. Nationally, 23 CFR 655.603 adopts the MUTCD as the national standard for all traffic control devices installed on any street, highway, or bicycle trail open to public travel in accordance with 23 U.S.C. 109(d) and 402(a).
Many cities and the Kansas Department of Transportation (KDOT) currently do not have their own versions of a guide for bicycle facilities. KDOT uses the American Association of State Highway and Transportation Officials (AASHTO) Guide for the development of Bicycle Facilities, 2012 edition as their guide. The AASHTO guide was used in the development of the MUTCD, and the MUTCD supersedes any discrepancies between the two.
Bicycle Lane Purpose
The MUTCD defines “Bicycle Lane” as:
“A portion of a roadway that has been designated for preferential or exclusive use by bicyclists by pavement markings and, if used, signs.”
Similarly, the AASHTO Guide for the Development of Bicycle Facilities defines a Bicycle Lane as:
“A portion of roadway that has been designated for preferential or exclusive use by bicyclists by pavement markings and, if used, signs. It is intended for one-way travel, usually in the same direction as the adjacent traffic lane, unless designed as a contra-flow lane.”
Chapter 4.6 of the AASHTO Guide addresses the design of bicycle lanes. It states in the General Considerations:
“Bike lanes are used to delineate available road space for preferential use by bicyclists. Bike lanes enable bicyclists to ride at their preferred speed, even when adjacent traffic speeds up or slows down. Bike lanes also encourage bicyclists to ride on the roadway in a position where they are more likely to be seen by motorists entering or exiting the roadway than they would be if riding on sidewalks.”
Chapter 3 of the AASHTO design guide discusses common contributing circumstances for bicycle crashes. Among other circumstances, it describes the two most common scenarios of motorists failing to yield at intersections. The second being the “right-hook” crash involving a right-turning motorist who strikes a through bicyclist. AASHTO recommends measures that increase bicyclist conspicuity such as lights, reflectors, and/or high visibility clothing as well as geometric roadway modifications that limit vehicle turning speeds.
The current edition of the Kansas Driving Handbook, Nov 2016, adopted by Governor Sam Brownback, also addresses vehicle and bicycle safety in Section 9: Sharing the Road. It offers suggestions to both bicyclists and drivers to promote safe interactions. For drivers, it includes:
“When approaching or passing a bicyclist slow down and allow as much space as possible and consider a bicyclist’s speed when you pass. If you are about to make a right turn, you must not pass a bicyclist immediately before the turn. To avoid a collision, you should slow down and let the cyclist clear the intersection before making your turn. Be careful after you have passed a bicyclist. Do not slow down or stop quickly. A motor vehicle’s brakes are more powerful than a bicycle’s and you could cause a crash.“ additionally, “Never turn sharply in front of a bicyclist and do not force a bicyclist off the road.”
The AASHTO A Policy for Geometric Design of Highways and Streets (also known as “the Green Book”) is the adopted standard for roadways on the National Highway System. The Green Book utilizes a typical vehicle deceleration rate of 11.2 ft/s2 for the design of vehicle facilities. In comparison, the AASHTO Guide for bicycle facilities recommends a bicycle deceleration rate of 8-10 ft/s2 on dry level pavement for the design of bicycle facilities; 11-29% slower than a motor vehicle.
Bicycle Lane Design Criteria
Chapter 9 of the MUTCD addresses traffic control devices for bicycle facilities. It states that markings indicate the separation of the lanes for road users, assist the bicyclist by indicating assigned travel paths, indicate correct position for traffic control signal actuation, and provide advance information for turning and crossing maneuvers. Additionally, pavement markings designate that portion of the roadway for preferential use by bicyclists. Markings inform all road users of the restricted nature of the bicycle lane. Longitudinal pavement markings shall be used to define bicycle lanes.
Chapter 3 of the MUTCD addresses pavement markings for roadways. It states that longitudinal lines shall delineate:
A. The separation of traffic flows in the same direction, or
B. The right-hand edge of the roadway.
The MUTCD, section 3A.06, states that a solid line discourages or prohibits crossing (depending on the specific application). 3D.01 states that preferential lanes, such as a bicycle or bus-only lane, symbol & word markings and lane longitudinal markings shall be used. All preferential lane symbols shall be white and positioned laterally in the center of the preferential lane. Where bicycle lanes exist contiguous to a general-purpose lane that can be traversed by motor vehicles, the bicycle lane shall be marked with either the bicycle symbol or the work marking BIKE LANE. The MUTCD defines the width of a normal longitudinal line to be 4 to 6 inches.
Occasionally, you will see a painted green lane which is for the exclusive use of bicyclists.
For the conditions found at the study location, the AASHTO guide recommends that bicycle lanes be established at a minimum of five feet wide and, where possible, include a painted or physical buffer from vehicle traffic; however, in extremely constrained circumstances, bicycle lanes can be four feet wide. Where the roadway has adjacent curbs, this distance is measured from the center of the bike lane line to the vertical face of the curb.
In addition to pavement markings, Chapter 9 of the MUTCD addresses signage for bicycle lanes. The Bike Lane (R3-17) sign and the R3-17aP and R3-17bP plaques (see Figure 9B-2) shall be used only in conjunction with marked bicycle lanes as described in Section 9C.04. If used, Bike Lane signs and plaques should be used in advance of the upstream end of the bicycle lane, at the downstream end of the bicycle lane, and at periodic intervals along the bicycle lane as determined by engineering judgment based on prevailing speed of bicycle and other traffic, block length, distances from adjacent intersections, and other considerations.
When the “BIKE LANE” sign (R3-17) is placed along a roadway, the MUTCD states that a minimum size of 24” x 18” shall be used.
Section 1A.12.03 defines white & black signs as a “regulation”.
The MUTCD states that where a preferential or exclusive lane for bicyclists (Bike Lane) is provided, it shall be defined by a 4-6 inch wide white longitudinal lane line and symbol markings, and may be accompanied by bike lane signage. The AASHTO bicycle facility guide recommends that bike lanes be five feet wide.
Summary and Conclusion
It’s my take that the general public including motorists and cyclists are not sure what to do with bike lanes. Unfortunately, neither do UPS drivers. Ride on!
The author thanks Matthew Parker, Professional Engineer, for his assistance and guidance in preparing this article. Thanks also to Kathy West for the photo.