Chapter 3
Recommended Countermeasures for Certain Problems Situations Associated with Bike Lanes & Wide Curb Lanes

Problem Situations

The parent study showed several factors to be consistently related to the occurrence of bicycle-motor vehicle conflicts: (1) presence of parked motor vehicles (either entering or exiting a legal parking space or illegal parking or stopping) in the BL or WCL, (2) presence of driveways or intersecting streets, and (3) provision of additional (usually turn) lanes at intersections that typically (but not always) resulted in a narrowing of the BL or WCL. A discussion of recommended countermeasures for these problem situations follows.

Parked Motor Vehicles

Motor vehicle parking conditions vary widely, and there can be large differences between all day parking with low turnover and high turnover parking that typically serves retail stores. High turnover from on-street parking was one of the situations that led to conflicts with bicycles in this study. The other problem situation was illegal parking or stopping in the bicycle facility. Many communities in the United States allow motor vehicles to park in bicycle facilities (particularly BLs) during some portions of the day, generally when bicycle traffic is low. In other words, there is no bicycle facility when motor vehicles are allowed to park. This practice can only function effectively if police enforcement keeps the motor vehicles out of the facility during the time parking is prohibited. However, this kind of enforcement is difficult to maintain, and violations of these parking provisions are apparent even in bicycle-friendly communities. Eliminating parking altogether in the bicycle facility is a much stronger statement. If bicycling is to be a truly integrated and useful form of transportation, then bicyclists should have facilities available throughout the day.

In like fashion, motor vehicles do not hesitate to pull into BLs to allow passengers to enter or exit. In areas of busy bicycle traffic, this can lead to many conflicts. At the least, standard "no parking in bike lane" signs (figure 15) should be used liberally. More often than not, however, this is an enforcement issue.

Besides enforcement, good design policy can help to eliminate some of the conflicts. If motor vehicle parking is an intended part of a BL (i.e., a combination BL with parking), then a double-striped 1.5- m BL that positions the right most BL stripe at least 0.9 m from parked vehicles is recommended to provide the best channelization of bicyclists (figure 16). At least 2.4 m should be allowed for parking. When available right-of-way does not allow the double striped BL described above, then a combination lane, intended for both motor vehicle parking and bicycle use, is an alternative. Such a lane should be at least 3.7 m wide, with 4.3 m being preferable, and contain parking T's (sometimes referred to as tick marks) to denote the parking spaces (figure 17).

Bicyclist education about correct position when riding on streets with on-street parking is also highly recommended. Bicyclists should be at least 0.9 m from parked vehicles, and riding should be in a straight line. Such recommendations can be easily highlighted on a community bicycle map.

Driveways and Intersecting Streets

Driveways and intersecting streets in either the midblock or intersection area can lead to bike/motor vehicle conflicts. Driveways or alleys in commercial areas are normally the culprits because more motor vehicle traffic is present. Sometimes the problem is the motorist driving out of a driveway or alley and failing to stop before crossing a sidewalk or an implied sidewalk area that has bicycle travel (figure 18). Clear sight lines should be provided for the motorist if possible. If the sidewalk ends at the driveway cut, a crosswalk could be painted (with optional advance stop bar), or the sidewalk could be extended across the driveway cut. A "WATCH FOR BICYCLISTS" sign could also be installed.

Treatments can also be developed for the bicyclist riding on the sidewalk. First and foremost, education should be provided about the dangers of sidewalk riding, and

especially wrong-way riding that places the bicyclist out of the normal viewing pattern for a motorist exiting from a commercial driveway or alley. Bicyclists should also be cautioned to ride slowly in these areas that are primarily designed for walking speeds. Painting "USE CAUTION" on the sidewalk at hazardous driveways is also recommended (figure 18).

Most of the problems noted at the high conflict rate sites in this project involved bicyclists riding in the street, however, and not on the sidewalk. From anecdotal observation, it would seem as though motorists are not hesitant to use a BL as a buffer when they exit from a commercial driveway or alley into the street. A remedy is to provide a stop bar for the motorist prior to the BL. "YIELD TO BICYCLISTS" signs may also be helpful (figure 19). Dashing the BL stripe at busy driveways is also recommended, not only to alert a motorist that a bicyclist may be approaching because of the presence of the BL but also to alert a bicyclist that a motorist may be emerging from the driveway adjacent to the dashed stripe.

Equally important is the problem of motorist overtaking where a right turn is made into the driveway soon after the overtaking is completed. The presence of the dashed BL stripe may also help to eliminate some of the serious conflicts and crashes that result from this maneuver. Bicyclist education about the danger of driveways is warranted, with the message focusing not only on motorist-drive-out but also on motorist-overtaking situations. Motorist education relating to the overtaking situation above is also needed.

Additional Lanes at Intersections There are several problems with additional lanes at intersections. One has to do with the loss of space to the BL or WCL when additional turn lanes are provided with the same width of cross section. It is common practice now to use narrower lanes

for turning movements or to calm traffic. Using narrower widths may retain the full width of the bike facility at the intersection.

Another practice involves terminating either the BL or WCL and splitting the approaching traffic into two through lanes just prior to the intersection stop bar area (figure 20). When this occurs, the two lanes often become one again on the far side of the intersection. The idea is to use the extra lane to get traffic through the intersection faster, but along with the notion comes problems for the bicyclist. First is the loss of space. Second is the weaving among the motorists as they jockey for position through the intersection and beyond as they must merge again.

Right turn lanes present another problem for bicyclists. There may be weaving between bicycles and motor vehicles in the approach to the right turn in a designated BL if there is a high volume of right turning motor vehicle traffic. Use ofa dashed stripe should be beneficial because the stripe gives notice that weaving will take place (figure 21). Bicyclists may also have a tendency to overtake or stop on the right of stopped or slow moving motor vehicles turning right. Education on the hazards associated with this maneuver is recommended.

Whether or not right turn lanes are present, right turning motor vehicles at intersections pose a problem for bicyclists. Similar to the driveway conflict mentioned above, in the intersection area a motor vehicle may also turn right to another street soon after overtaking a bicyclist. One treatment made popular in Europe that helps to counter this problem is the use of an advanced stop bar or bike box (the term now frequently used to refer to this treatment in the United States). In Europe, a bike box is typically placed at the end of a BL (figure 22) so that bicyclists may proceed easily to the head of the traffic queue and thus get through the intersection ahead of right turning motor vehicle traffic. The bike box is gaining some popularity in the United States, and different versions of the technique are being tried or considered, such as placing a bike box at a WCL intersection, or using the bike box at a BL location to get left turning bicyclists to the head of the queue. The bike box appears to be well accepted in Europe. However, evaluations of such applications in the United States need to be made to determine if the applications are understood and accepted.

Recent Countermeasure Research Findings from Other Countries

There is quite a bit if research available from other countries indicating that the use of symbols, color, and other devices reduce conflicts and crashes at intersections. Almost all of these studies pertain to BLs. It is likely that the use of the markings and color alerts other road users to the presence of bicycle traffic. Brief summaries are provided below:

In a study in Denmark, Jensen et al., (1997) found that the marking of bicycle travel paths with blue paint and/or raised pavement at signalized intersections resulted in 36 percent fewer bicycle-motor vehicle crashes and 57 percent fewer bicyclists who were killed or severely injured.

At five intersections in Montreal, colored bicycle crossings were installed, with the pavement colored blue at bicycle path crossing points. After the markings were painted, bicyclists were more likely to obey stop signs and to stay on designated cycle path crossings. Improved bicyclist behavior led to a decline in the level of conflict between cyclists and motorists (Pronovost and Lusginan, 1996).

A raised and painted bicycle path (crossing) introduced at 44 intersections in Gothenburg, Sweden, reduced motor vehicle speeds (by 35 to 40 percent for right-turning motor vehicles) and increased cyclist speeds (by 10 to 15 percent). The safety improvement was estimated by using a quantitative model and by surveying bicyclists and experts. The model estimated the combined effect of lower motorist speeds and higher bicyclist speeds to be a 10 percent reduction in the number of bicycle-motor vehicle crashes. Bicyclists perceived a 20 percent improvement in safety after the bicycle path was raised and painted. Experts estimated a 30 percent improvement in safety. However, the authors suggested that the total numbers of crashes should be expected to increase due to a 50 percent increase in bicyclists using the improved crossings (Leden, 1997). A follow-on paper using a Bayesian approach for combining the results of the model and surveys estimated a risk reduction of approximately 30 percent attributable to the raised and painted crossing (Gårder, Leden, and Pulkkinen, 1998).

A variety of other countermeasures, such as traffic signal heads that specifically control bicycle traffic, are mentioned in the FHWA Study Tour for Pedestrian and Bicyclist Safety in England, Germany, and The Netherlands (Zegeer et al., 1994).

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