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CHAPTER 1 Introduction 1.1 Why These Guidelines? Major metropolitan regions across the United States today face various mobility challenges such as deteriorating travel reliability due to increased peak-period congestion, lengthening dura- tions of peak travel periods, and underutilization of existing capacity during off-peak periods. There is growing national momentum within government transportation agencies to use con- gestion pricing--a strategy that combines both physical and operational improvements--as a tool to address these challenges and also generate new revenue sources which can be used to fund transportation improve- ments. In late 2010, there were 11 operating high-occupancy Key Definitions toll (HOT) lane facilities in the United States and a much Congestion Pricing--the application of variable larger number in different stages of development, including fees or tolls on roadways to manage available extensive regional networks in some cases. In addition, a small capacity and user demand number of toll authorities have introduced variable pricing on Performance Measure or Metric--used inter- existing toll facilities, while some new facilities have begun changeably, a quantitative or qualitative operations featuring time-of-day pricing. Finally, two major characterization of a facility or scheme's opera- metropolitan areas are considering or have considered the tional properties; performance measures inform possible implementation of cordon or area pricing schemes. a performance evaluation These schemes require motorists to pay a fee to enter a desig- Performance Monitoring--the ongoing, struc- nated urban zone, typically a city center, during congested peak tured process of compiling performance measure periods. Similar systems are currently operating in Singapore, data; performance monitoring results can be London, and Stockholm. reported and/or retained for historical purposes; The use of congestion pricing and congestion management performance monitoring is also required to techniques has received further attention with the passage of undertake a performance evaluation the Safe, Accountable, Flexible, Efficient Transportation Equity Performance Evaluation--an assessment of a Act: A Legacy for Users (SAFETEA-LU) in 2005. This legisla- facility or scheme's operation relative to expecta- tion provides state departments of transportation (DOTs) the tion or a set of prescribed parameters; a per- flexibility to convert existing high-occupancy vehicle (HOV) formance evaluation can be used to make set lanes to HOT operation and also encourages the use of other adjustments to a facility or scheme's operation congestion pricing strategies. Subsequently, the United States (e.g. based on an established algorithm) or used Department of Transportation (US DOT) established two to make operational adjustments based on judg- one-time initiatives--the Urban Partnership Agreement ment and the weighing of present factors (e.g. (UPA) and Congestion Reduction Demonstration (CRD) costs, benefits, or risks) programs--to demonstrate how a variety of pricing concepts Note: Because performance monitoring data is a direct can be used together with other strategies to reduce conges- input to a performance evaluation, the two terms are occasionally interchanged tion and tap into new sources of revenue. These programs are funding projects combining different forms of congestion 3

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4 Evaluation and Performance Measurement of Congestion Pricing Projects pricing with transit enhancements, parking strategies, telecommuting, intelligent transportation system (ITS) applications, and operational improvements as tools to reduce congestion. Together they represent a Federal investment of over $700 million. With widespread interest in using congestion pricing to manage congestion and generate new revenue streams, there is a need to document the performance of existing priced facilities. This is particularly important because congestion pricing strategies often face considerable political and public pressures and are not widely known or appreciated by the public at large. Moreover, with a relatively small number of congestion pricing facilities operating in the United States, there is a lack of comprehensive information for developing overall performance evaluation pro- An Early Glut of HOV Performance Data Followed by a Dearth When HOV lanes were first being introduced in selected cities, often under the auspices of demonstration proj- ect status, considerable scrutiny was given to the performance of each project. There was keen interest in whether a dedicated lane would successfully induce mode and spatial shifts and meet stated goals. Accord- ingly, data was often collected on users, traffic demand on the corridor and parallel routes, travel times, crash and violation rates, before and after trip characteristics, and a wide range of other factors. Some locales issued initial status reports on a weekly or monthly basis. This investment left practitioners with a rich set of resources from which to later understand what worked and what didn't. While most demonstrations tracked these mea- sures rigorously, follow-on projects also tracked performance-related safety, air quality, modal shifts, public attitudes, and, in some cases, even land use values in the respective corridor. As these projects proved themselves and became accepted by sponsoring agencies and users, there was less need evidenced in most places to invest as rigorously in performance monitoring. With some regional excep- tions, as findings from performance monitoring informed best practices in designing and operating preferen- tial lanes, standards of practice and guidance emerged. These became accepted at corridor, regional/state, and national levels on such topics as buffer separation width, hours of operation, enforcement area treatment, access and occupancy restrictions, to name a few. Many areas have held to these standards of practice since they are understood by local motorists and participating agencies, and have, by most anecdotal accounts, worked satisfactorily. Accepted HOV practices have inadvertently led to less and less investment in performance monitoring and reporting by respective sponsoring agencies. While many areas continue to monitor basic information related to the number and operation of such HOV projects within their jurisdiction, few have budget resources to reg- ularly track and report on such measures as safety and enforcement, performance by mode, design efficacy, or constituent attitudes. So they are often ill-prepared for sudden inquiries that question whether the lanes are continuing to respond to their stated goals and objectives. Exceptions arise when extraordinary events or pub- lic or political scrutiny require responses to specific questions or changes in operation. In these instances data is collected and evaluated to respond specifically to the issue of an inquiry or design/operational change. In sum- mary, if the HOV lanes are working satisfactorily, only monitoring of a few measures is typically conducted on a regular basis. The advent of pricing on HOV lanes has renewed interest in performance monitoring on at least the first projects in each locale, primarily to gain an understanding of how this new tool works. If history is any indication, lessons learned from these early pricing projects will also set forth commonly accepted practices, which may in turn, result in lessening interest and investment in performance monitoring. Conversely, having a customer/business proposition that requires continuing and real-time management oversight and a revenue stream that can be used to underwrite monitoring activities offers the opportunity to ensure an ongoing commitment to this needed resource.