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40 CHAPTER FOUR CONCLUSIONS AND FURTHER RESEARCH Bus use of shoulder operations have been working success- to provide a detailed record of the policy and analytical fully for more than a decade in several locations. They have processes. Implementation of these new projects will prove been implemented in a variety of forms for a variety of pur- useful at providing a more quantitative understanding of poses, but they appear to have a number of common traits. Bus BBS. bypass shoulder (BBS) applications minimize congestion- related schedule reliability problems, improve the competi- A cooperative or partnership approach involving transit tive travel times for buses versus cars, are low cost and easy operations, departments of transportation, police, and metro- to implement, do not require new rights-of-way, and are not politan planning organizations appears to be crucial in plan- visually obtrusive. The early BBS projects appear to have ning, implementing, and operating BBS projects. been implemented without rigorous analysis and their success is reflected in the absence of post-project evaluation reviews Of the study objectives of this synthesis report, data on and also by the expanding list of BBS projects. If accidents many of the issues were either not readily available or not had proven to be a problem, safety evaluations would likely available at all. Better information would be useful to com- have been conducted and some BBS projects might have been munities considering implementation of BBS and those abandoned. The few very short segments of BBS that have interested in improving current BBS projects. It might also be been abandoned are understood to have been upgraded to full valuable for "New Starts" project alternative definitions and bus lane operations. Indeed, the BBS practice is expanding, evaluations. Information on early BBS projects is primarily particularly in communities that have established BBS expe- limited to what can be observed on the highways. Little history rience. Georgia has recently joined the list of states with BBS exists on the institutional, legal project development process, operations, California has implemented a pilot project, and costs, and performance of these early BBS projects. This Florida is scheduled to begin limited BBS operations. BBS's important information is becoming available for the more context-sensitive design features (low visual impact), low recent and the planned projects (i.e., Georgia 400, planned cost, ease of implementation, and support of more efficient MiamiDade BBS, and San Diego BBS). and attractive transit services are features that resonate with numerous public policies. What is clear is that the an increasing number of commu- nities are pursuing shoulder use projects and that an imple- The BBS concept also appears to be popular with bus pas- mentation checklist and a TCRP document similar to that sengers, who enjoy the feeling of preference as their bus moves prepared for TCRP Report 90: Bus Rapid Transit, might be past stop-and-go traffic in the general purpose traffic lanes. It is useful. not uncommon for passengers to suggest to bus drivers that they move onto the shoulder when traffic begins to slow. Their Key issues warranting further research are: perceived travel time benefits are generally greater than actual, but because perception is a key factor in affecting travel choices What are the market and patronage benefits associated and increasing transit market share it is very important. with BBS and how can project design maximize these benefits? Surveys might be useful to better understand Although the bus use of shoulders is not an ideal highway/ passenger perceptions as well as the perceptions of traffic operations concept, its 10-year-plus operations history motorists using the adjacent general purpose lanes. in the Minneapolis metropolitan area indicates that it can Understanding the perceptions of these groups might be implemented relatively effectively and safely. The Twin help to design better BBS projects as well as provide Cities BBS application is a very low-cost effort with respect guidance to marketing efforts. Quantification of before to pavement markings and signage, yet this low level signage and after patronage in corridors is also needed. and markings operation has proven to be safe. What are the bus running time and reliability benefits resulting from BBS operations? Tracking bus service Actual data on operations and patronage benefits is performance using global positioning systems could sketchy for established BBS operations, as are the processes help to quantify operational benefits. A survey of bus used to implement the shoulder use projects. Newer BBS drivers could complement the global positioning sys- project implementations are tending to be more rigorous and tem monitoring program and provide added insights

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41 into program benefits and opportunities to enhance the for BBS transitions and interchange ramp weave areas? BBS concept. What is the minimum pavement strength required? How What is the safety history of BBS operations and how important are modifications to drainage inlets? What might the design of BBS applications minimize safety are the desired and maximum drainage cross slopes for risks? From a review of accident data and discussions BBS shoulders? What lighting improvements, if any, are with enforcement and driver training and bus safety desired for the BBS segments? What minimums can be staff, key safety concerns and myths might be described. accepted, particularly for interim applications? Most of the BBS projects that have been implemented What signage and striping guidelines and standards are employed a multi-agency team planning, design, and im- recommended and could these be included in the next plementation approach. More information is required on update of the Manual on Uniform and Traffic Control these multi-agency partnership efforts, as well as legal Devices? aspects of project implementation. How might variable or changeable message signs and What geometric improvements are needed and what are ITS technologies be used to improve BBS safety? their guidelines for costs? The minimum widths need What speeds are safe for BBS operations and how do further definition. Should shoulders be wider on bridges bus volumes and shoulder width dimensions influence and underpasses and other segments with horizontal ob- safe speeds? structions nearby? Is there a maximum distance that min- What are the advantages and disadvantages of speed- imum width shoulders are tolerable? Should shoulders limited BBS operations versus Ottawa's higher speed be wider at sharp curves? What are desired geometrics operations?