The debate over whether BLs or WCLs are preferable has been heated for many years. While both BLs and WCLs are acceptable facilities in many locations, the debate has sometimes forced decision makers to choose which facility type they prefer, to the exclusion of the other. More bicycle facilities might be in place in this country except for this long-standing division of opinion.

This comparative analysis of BL versus WCL sites utilized an extensive data base to examine many factors related to the operations and safety of these facilities. Forty-eight sites from three cities were videotaped in the study, and these produced 369 total conflicts, 276 of which were bike/motor vehicle conflicts. In reality this is relatively few conflicts, which is an encouraging outcome. On the other hand, approximately 6 percent of the bicyclists had a conflict with a motor vehicle, which is not a trivial amount. Many more sites would have been necessary to produce a wholesale increase in the number of conflicts available for analysis.

Across the board these facilities work well, with the vast majority of identified conflicts in this study being minor in nature. Both behavioral actions and geometric characteristics were identified as problems in the study of these bicycle facilities, and there are remedies for these. However, in most cases the noted problems at the higher conflict rate sites could not be labeled as particular BL or WCL deficiencies. The destination patterns of bicyclists traveling

through the project sites led to maneuvers and conflicts that in many cases would have occurred whether the bicycle facility present was either a BL or WCL.

This is an important point that planners and engineers should heed. With their relative freedom of movement (i.e., not being as confined to a traffic lane as a motor vehicle), bicyclists will use a variety of ways to get through an intersection and on toward their destination. The chosen methods usually reflect perceived time savings/efficiency or improved safety. As an example, difficulties in making left turns because of heavy motor vehicle flows will likely lead to advance crossovers or other alternate maneuvers. Even though standard design templates for bicycle facilities should be applied wherever possible to promote consistency in understanding and proper movements through intersections, it is apparent that such templates cannot be used across the board to achieve standard or desired bicyclist movements. Some tailoring will be necessary to take into account desired or frequent movements by bicyclists, just as is done for locations with high motor vehicle movements and/or crash rates.

The overall conclusion of this research is that both BL and WCL facilities can and should be used to improve riding conditions for bicyclists, and this should be viewed as a positive finding for the bicycling community. The identified differences in operations and conflicts were related to the specific destination patterns of bicyclists riding through the intersection areas studied. Given the stated preferences of bicyclists for BLs in prior surveys (e.g., Rodale Press, 1992) along with increased comfort level on BLs found in developing the Bicycle Compatibility Index (Harkey et al., 1998), use of this facility is recommended where there is adequate width, in that BLs are more likely to increase the amount of bicycling than WCLs. Increased bicycling is important because in the United States there are but a few communities that have a significant share of trips made by this mode. Overall, we have not yet reached the critical mass necessary to make motorists and pedestrians aware of the regular presence of the bicycle. When this critical level of bicycling is reached, gains in a "share the road" mentality will come much more quickly than at present. Certainly not all the problems will disappear, but the ability to develop and implement solutions will be greatly enhanced.

[Table of Contents] [Chapter 1] [Chapter 2] [Chapter 3] [Chapter 4]