Texas A&M Transportation Institute

Transportation Policy Research

Bicycle Lanes

Congestion

Introduction

Bicycle lanes mark a safe space on the road for bicyclists to ride. The American Association of State Highway and Transportation Officials (AASHTO) says that bicycle lanes “…are the appropriate and preferred bicycle facility for thoroughfares in both urban and suburban areas.”1

Bicycle lanes improve safety by:

  • Increasing the number of bicyclists riding in the correct direction.
  • Making bicyclist positioning in the lane more predictable for motorists.
  • Decreasing the number of motorists swerving into other lanes to get around the bicyclist.

Bicycle lanes also increase the street’s efficiency by providing space for both bicycles and vehicles. The bicycle lane encourages more bicycling, allowing the street to move more people.

Bicycle lanes let bicyclists ride at their own speed near moving vehicles. Markings show bicyclists and motorists where their operating space is on the roadway. Bicyclists are allowed to leave the bicycle lane to pass other bicyclists, make right or left turns, pass stopped vehicles, or avoid objects. 

Executive Summary

info box_bikelanes copy

Bicycle lanes can be as simple as adding a symbol on an existing shoulder—or as elaborate as meeting the full design criteria and including signs and pavement markings. Conventional bicycle lane markings include a 4- to 6-inch solid white line, the bicycle symbol, an arrow showing direction of travel, and a black BIKE LANE sign.

The Manual on Uniform Traffic Control Devices (MUTCD) also allows several variations.2 In addition to conventional bicycle lanes, transportation agencies can use:

  • Striped buffers to add separation between bicycles and vehicles.
  • Pavement coloring to show conflict points with vehicles.
  • Contra-flow bicycle lanes to allow two-way bicycle access on a one-way street.2

Target Market

Bicycle lanes can be effective anywhere bicyclists and motorists can come into conflict but are most effective in the following locations:

  • Urban, mixed-use areas or on paralleling congested roadways. Bicycle lanes can reduce congestion in these areas.
  • Arterial and collector streets with moderate vehicle speeds that connect residential areas to employment and shopping centers.

Bicycle lanes are particularly helpful on roadways with more than 3,000 vehicles per day or with moderate vehicle speeds.3 Population density likely affects how much bicycle lanes reduce vehicle congestion.4

How Will This Help?

  • Reduces vehicle congestion. Bicycle lanes provide an alternative for shorter trips and increase the efficiency of the street for vehicles and bicycles.5 The bicycle lane separates automobiles from slower bicycle traffic and allows bicyclists to bypass vehicle congestion.6
  • Improves air quality. Fewer vehicles on the road mean reduced combustion engine use and better air quality. A bicycle lane separated from vehicles produces better air quality for bicyclists and pedestrians.7
  • Reduces bicyclist and vehicle crashes. Bicycle lanes improve safety by separating traffic, reducing vehicle encroachments into other lanes, and highlighting conflict points.8

Implementation Examples

Application Techniques and Principles

Based on previous guidance from AASHTO, Texas and other states often include wide curb lanes along with bicycle lanes.8 Studies spanning more than 30 years found bicycle lanes to be a safer facility than having bicycles share the outside lane with automobile traffic.10 The bicycle lane is the current standard bicycle accommodation that AASHTO recommends.1

In 2013, the Federal Highway Administration (FHWA) recognized two documents in addition to the MUTCD:

  • The Institute of Transportation Engineers (ITE) Designing Urban Walkable Thoroughfares.12
  • The National Association of City Transportation Officials (NACTO) Urban Bikeway Design Guide.3

With these two documents, FHWA recognizes the importance of a flexible approach to bicycle and pedestrian facility design. Each guide provides information on optimal bicycle lane planning and design, suitable for many different situations.

ITE Guide
Bicycle lanes can be used in many contexts and applications. ITE’s guide recommends a 6-foot bicycle lane (5 feet minimum) for its thoroughfare standards; thoroughfares range from residential streets to six-lane boulevards.13 The ITE guide reports bicycle lanes as desirable “…on major thoroughfares with target speeds of 30 mph or more and on streets with high traffic volumes and speeds less than 30 mph.” ITE also recommends using bicycle lanes as a way to visually narrow streets to calm traffic, after assessing traffic operations and other needs of the street.12

The guide also discusses potential conflicts between the bicycle lane and parking. Bicyclists can be hurt by motorists opening vehicle doors that jut into their lane. Figure 2 shows that a conventional bicycle lane provides enough space for the bicycle to pass the parked vehicle, but additional separation such as a striped buffer zone could be even more helpful.

NACTO Guide
Among the new features in the NACTO guide, green pavement markings improve the visibility of a bicycle lane. Green pavement markings can also extend a bicycle lane into an intersection. FHWA has given interim approval for this use under the MUTCD.14

Issues

Constrained Right of Way
In some areas, it may be difficult to make room for bicycle lanes. AASHTO recommends several options to retrofit bicycle facilities without widening the road:1

  • Reduce or reallocate the width used by travel lanes.
  • Reduce the number of travel lanes.
  • Reconfigure or reduce on-street parking.

Reducing the Number of Travel Lanes
FHWA says that roadways with average daily traffic of 20,000 or fewer vehicles per day may be good candidates for road diets.7 Road diets reduce the number of vehicle travel lanes and provide an option to add bicycle lanes.1

AASHTO reports that conversion of a four-lane (two-way) roadway to a three-lane roadway with a two-way left-turn lane has several operational benefits:1

  • “…virtually eliminates the likelihood of ‘multiple threat’ crashes where a driver in one lane stops to yield, but the driver in the adjacent lane continues at speed for pedestrians and left-turning motorists and bicyclists.”
  • “…provide a place for motorists and bicycles to wait to make a left turn, reducing the incidence of left-turn, rear-end crashes.”
  • “Sideswipe crashes are reduced since motorists no longer need to change lanes to pass a vehicle waiting to turn left from the leftmost through lane.”
  • “Less traffic noise (due to reduced speeds) and greater separation from traffic for pedestrians, residents, and businesses.”

FHWA reports crashes on road diet conversions have been reduced by 29 percent for all users.7

Reducing or Reallocating the Width Used by Travel Lanes
AASHTO’s A Policy on Geometric Design of Highways and Streets contains criteria for lane widths and allows narrow vehicle lanes (10 feet) in many situations. Four-lane arterials with turning lanes can be re-striped during routine maintenance to also include bicycle lanes.

Reconfiguring or Reducing On-Street Parking
Reducing on-street parking can make space for bicycle lanes and can have both positive and negative effects for users and neighbors. In many cases, bicycle lanes can be added by removing parking from one side of the street and narrowing vehicle lanes (if necessary), while retaining some parking for residences and businesses.1 Diagonal parking can be converted to parallel parking to provide additional space.

Traffic Signalization
Adding a bicycle lane may also mean improving traffic signalization. The Arizona Department of Transportation’s Statewide Bicycle and Pedestrian Plan says signal detectors for bicycles should be considered for signalized intersections. A stenciled marking tells bicyclists where to stop in order to be detected (though many new detection methods detect bicycles without being in a specified location).

Maintenance
Maintenance needs for bicycle lanes are similar to those for vehicle lanes. Maintenance includes:

  • Keeping lane lines and stencil markings clear and legible.
  • Keeping the lanes free of potholes and debris.
  • Backfilling trenching or utility cuts to the same degree of smoothness as the original surface.9

Who Is Responsible?

Transportation agencies that design and manage roadways are responsible for implementing bicycle facilities. Cities often work with state departments of transportation on these projects, particularly when crossing state right of way, to provide a continuous facility for all road users. Public involvement helps address details such as changes to on-street parking.

Project Time Frame

Assuming funding is available, individual bicycle lane projects can take between two months to over a year for planning and public involvement, design, and construction. However, if a community has a well-vetted plan identifying system configuration and project feasibility, bicycle lane projects can be performed during resurfacing projects on an ongoing basis.

Cost

Installing bicycle lanes is most cost efficient during the original construction, street resurfacing, or reconstruction. Adding bicycle lanes can cost as little as $5,000 per mile. The condition of the pavement, the need to remove and repaint lane lines, traffic signal adjustments, and other factors can drive up costs to $50,000 per mile.8

Data Needs

  • Bicycle and vehicle traffic counts taken before and after bicycle lane installation help evaluate traffic throughput.
  • Crash records can help planners determine how important bicycle lanes are for safety. An analysis of the causes of crashes can help planners optimize the design features for safety.

Bicycle Lane Best Practices

Type of location: Streets with either moderate to high speeds or traffic volumes. Greater demand is likely in urban, mixed-use areas.
Agency practices: Review updated design guidance and compare it to existing agency practices. Include experienced designers to expand staff knowledge of new facilities.
Frequency of reanalysis: Annual review of volumes and crash data to support accurate performance measurement and control for seasonality.
Supporting policies or actions needed: Modernize planning and design guidance to reflect recent standards and research. Provide training for transportation agencies to implement bicycle lanes effectively and with minimal cost.
Complementary strategies: Bicycle sharing, bicycle/pedestrian education and encouragement, cycle tracks, active demand management, and trip reduction ordinances.

For More Information

Torbic, D. J., K. M. Bauer, C. A. Fees, D. W. Harwood, R. Van Houten, J. LaPlante, and N. Roseberry. NCHRP 766 Recommended Bicycle Lane Widths for Various Roadway Characteristics. Transportation Research Board, Washington, D.C., 2014.
USDOT/FHWA: Bicycle and Pedestrian Facility Design Flexibility.
U.S. Federal Highway Administration. “Road Diet” (Roadway Configuration) Proven Safety Countermeasures, # FHWA-SA-12-013. Washington, D.C., 2013.
North American City Transportation Officials: Conventional Bike Lanes.
Transit Cooperative Research Program. Transit Capacity and Quality of Service Manual, Second Edition. Washington, D.C., 2003.

References

  1. American Association of State Highway and Transportation Officials. Guide for the Development of Bicycle Facilities. American Association of State Highway and Transportation Officials, Washington, D.C., 2012.
  2. U.S. Federal Highway Administration. Bicycle Facilities and the Manual on Uniform Traffic Control Devices. http://www.fhwa.dot.gov/environment/bicycle_pedestrian/guidance/design_guidance/mutcd_bike.cfm
  3. National Association of City Transportation Officials. NACTO Urban Bikeway Design Guide. Island Press, Washington, DC, 2014.
  4. Furth, P. Bicycling Infrastructure for Mass Cycling: A Transatlantic Comparison. In City Cycling (J. Pucher and R. Buehler, eds.), MIT Press, Cambridge, MA, pp. 105–139.
  5. Krizek, K. J., and et al. NCHRP Report 552 Guidelines for Analysis of Investments in Bicycle Facilities. 2006.
  6. Hunter, W. W., L. Thomas, and J. C. Stutts. Chapter 5 – Countermeasures. In BIKESAFE: Bicycle Countermeasure Selection System, U.S. Department of Transportation Federal Highway Administration, Washington, D.C.
  7. Kendrick, C. M., A. Moore, A. Haire, A. Bigazzi, M. Figliozzi, C. M. Monsere, and L. George. Impact of Bicycle Lane Characteristics on Exposure of Bicyclists to Traffic-Related Particulate Matter. Transportation Research Record: Journal of the Transportation Research Board, Vol. 2247, Dec. 2011, pp. 24–32.
  8. Lusk, A. C., P. Morency, L. F. Miranda-Moreno, W. C. Willett, and J. T. Dennerlein. Bicycle Guidelines and Crash Rates on Cycle Tracks in the United States. American journal of public health, Vol. 103, No. 7, May 2013.
  9. Austin Transportation Department. Redesigning the Street: A report on right-sizing projects in Austin TX 1999-2014. Austin, TX, 2015.
  10. Henao, A., D. Piatkowski, K. S. Luckey, K. Nordback, W. E. Marshall, and K. J. Krizek. Sustainable transportation infrastructure investments and mode share changes: A 20-year background of Boulder, Colorado. Transport Policy, Vol. 37, No. 2015, 2015, pp. 64–71.
  11. Pratt, R. H., J. E. (Jay) Evans, H. S. Levinson, S. M. Turner, C. Y. (C. Y. . Jeng, J. E. Jay Evans, and D. Nabors. Pedestrian and Bicycle Facilities. In TCRP Report 95, Traveler Response to Transportation System Changes, Transportation Research Board, Washington, D.C.
  12. Institute of Transportation Engineers. Designing walkable urban thoroughfares: a context sensitive approach. Institute of Transportation Engineers, 2010.
  13. Barton, J. A. Guidelines Emphasizing Bicycle and Pedestrian Accommodations.
  14. U.S. Federal Highway Administration. Interim Approval for Optional Use of Green Colored Pavement for Bike Lanes (IA-14).