Bus Use of Shoulders (2006)

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3BACKGROUND In many urban areas, traffic congestion regularly delays bus services and adversely affects schedule reliability. Many com- munities have adopted measures such as bus priority lanes, bus signal priorities, or improved fare collection policies to im- prove speed and reliability. Some communities have adopted policies and regulations that permit buses to use arterial or freeway shoulders to bypass congestion either as interim or long-term treatments. At the outset of the study, Maryland, Minnesota, Virginia, Washington, British Columbia, and Ontario were among the jurisdictions that had implemented or were considering implementing bus use of shoulder programs. However, because little information was available about travel time, reliability, patronage benefits, and safety impacts result- ing from allowed use of shoulders, many jurisdictions have been reluctant to embrace bus use of shoulders. Buses bypassing traffic congestion on shoulder lanes can help make bus use more attractive. Travel time reliability and travel time competitiveness are both key factors that attract “choice riders” to bus transportation. These are basic advan- tages that rail and bus systems operating on exclusive rights- of-way provide, and they help to explain why these systems are more successful than conventional bus services operating in mixed-use traffic. The marketing and psychological mes- sage of buses passing motorists stuck in traffic congestion tends to be powerful. In essence, bus bypass shoulder (BBS) use operations reduce passenger travel times and help improve travel time reliability. BBS is used by a number of agencies to describe bus use of shoulders. This acronym was adopted for use in this report and is suggested for use in subsequent technical reports. Along many congested freeway corridors, widening to provide a bus-only lane is not a viable option because of right- of-way constraints, environmental concerns, and/or high cost. In these restricted corridors the use of outside shoulders by buses to bypass congestion provides a means to increase the person carrying capacity of the corridor without expanding rights-of-way. The shoulder use concept is less disruptive than widening projects to implement, is relatively low cost, and can be put into practice relatively quickly. Visually, the BBS concept is less obtrusive than large highway ramps con- structed to allow buses direct access into center median high- occupancy vehicle (HOV) lanes. A potential application for BBS is to support “station stop- ping” bus operation along highways with center median HOV lanes. Station stopping buses follow bus routes that make many passenger stops at interchanges along a corridor. This mode of bus operation is similar to the operation of most light rail systems, which make station stops approximately every mile along major travel corridors. Use of median HOV lanes for station stopping bus routes tends to be very challenging, particularly where freeway buses stop at each interchange or every other interchange. These short station distances make bus weaving to and from the median HOV lanes problematic. Significant time is lost, disruption is increased to the HOV traffic flow and intervening travel lanes, and safety concerns arise with these short distance bus weaves. To contend with these issues a number of agencies have constructed expensive direct access ramps to the HOV lanes. Another potential application is that of a “queue jumper,” allowing buses to bypass congestion at a traffic bottleneck. These applications tend to be short and to involve no or only minimum ramp weaving conflicts. The short lengths of these queue jumper applications often require minimal shoulder upgrade cost and can provide significant travel time and reliability benefits. Permitting buses to use shoulder lanes to bypass conges- tion, however, raises potential conflicts with the intended purpose of shoulder facilities. Highway shoulders generally provide space for disabled vehicles, emergency services, and enforcement efforts. They also provide a safety buffer and re- covery area between the general travel lanes and lateral obstructions. In snow climate areas they can be used for tem- porary snow removal. They are not intended to be used for debris storage, but sometimes serve this function. Allowing buses to use the shoulder lanes therefore compromises these basic shoulder functions. The extent of these compromises varies by corridor and is difficult to quantify. Another important issue is that most shoulders are not con- structed to the full structural requirement as general traffic lanes and most are narrower than conventional traffic lanes. Design requirements for shoulder facilities vary by state and have included upgrades over the years. Older highways tend to have the narrowest and least accommodating design standards. AASHTO’s A Policy on Geometric Designs of Highways and Streets (1) currently recommends a minimum 10-ft-wide right shoulder for highways with modest volumes CHAPTER ONE INTRODUCTION

of trucks (fewer than 250 trucks per hour) and 12 ft wide for highways with high truck volumes. Shoulder cross slopes for drainage purposes are typically 2% to 6%. Some shoulders also have storm drain catch basins and electrical junction boxes located within their right-of-way. The cost and right- of-way implications on adjacent lane widths may therefore become a problem in converting the shoulder facilities to accommodate heavy buses. Safety is always an important issue. In addition to concerns raised about compromising the intended functions for freeway shoulders, concerns exist regarding increased accident risk. Most motorists do not expect traffic in the shoulder “lane” and therefore the potential for accidents increases for basic on- and off-ramp traffic maneuvers as well as for motorists moving onto the shoulder when their vehicle becomes disabled. A number of communities allow general traffic to use shoulder lanes during peak commute times. This TCRP synthesis report focuses only on shoulder use applications restricted to buses. SCOPE The two purposes of this synthesis are to: 1. Identify and obtain information and experiences about jurisdictions that allow bus use of shoulders, and 2. Identify and obtain information about which jurisdic- tions have considered but have not implemented these treatments and the reasons why. The transit and highway perspectives on bus shoulder op- erations are reviewed, recognizing that both must be partners in expanding promising applications for increasing patron- age and improving operating efficiency. The following types of information were sought: • Institutional setting; • Planning, design, and implementation process; • Legal aspects (liability, legal requirements, and vehicle codes, etc.); • Operating guidelines (operating speeds, hours of use, driver operating instructions, etc.); • Design standards and/or required physical improve- ments, including traffic markings and signage, lane widths, pavement depths, drainage, etc.; • Maintenance and roadway performance; • Enforcement and violation experience; • Bus and passenger volumes; • Impact on highway operations; • Safety experience; 4 • Eligibility requirements (who may use the shoulder); • Benefits and impacts (travel time savings, reliability im- provements, affordability, ease of implementation, etc.); • Driver and passenger attitudes; • Costs (construction, maintenance, bus operations, etc.); and • Use of emerging technologies. A review of the relevant literature was combined with sur- veys of selected transit agencies and roadway jurisdictions to define the current state of the practice. Based on the survey results, in-depth case studies were developed to profile inno- vative and successful practices, as well as lessons learned, including where and why implementation did not occur. Gaps in the desired information were substantial. DEFINITIONS AND ACRONYMS BBS (bus bypass shoulder)—used in this report to describe bus use of highway shoulder lanes to bypass congestion. It does not include shoulders used for general traffic or on-ramp bypasses. MUTCD—Manual of Uniform Traffic Control Devices for Streets and Highways (2), published by FHWA. Station stopping—a mode of bus operations on freeways where buses on a route make stops at all or most inter- changes along the corridor. Queue jumper—physical facility that allows eligible traffic to bypass localized congestion. HOV (high-occupancy vehicle)—generally defined as ei- ther two or more or three or more persons per vehicle. Direct HOV access ramps—most HOV lanes are located in the median of freeways and require carpoolers and buses to weave across general traffic lanes to enter and exit the freeway using ramps located on the right side of the free- ways. Direct access ramps eliminate the weaving for buses and HOVs by providing entry and exit access ramps directly to the center median HOV lanes. These direct ramps are costly, need additional rights-of-way, and add to the visual impact of freeway interchanges. REPORT ORGANIZATION Following the introductory chapter, the synthesis provides an overview of findings (chapter two), which is followed by case studies (chapter three) and the conclusions and sug- gested areas for further research (chapter four). Case study descriptions were prepared for the Minneapolis–St. Paul Twin Cities Area; Falls Church, Virginia; Miami, Florida; San Diego, California; Toronto, Canada; and Dublin, Ireland. Survey questionnaire tools and respondents are iden- tified in the appendixes.