Bottleneck Merge Control Strategies for Work Zones: Available Options and Current Practices

Abstract

Maintenance and rehabilitation projects of interstate facilities typically mandate lane closures. Lane closures require merging maneuvers that often result in reduced speeds and traffic bottlenecks. Conventionally, bottleneck merge control plans are developed to address bottlenecks impacts. However, there is a need to better understand the various merge control options and their potential impacts on traffic operations and safety. This study reviewed available options and current practices of bottleneck merge control strategies at work zones, and summarized transportation agencies’ considerations to mitigate adverse impacts. An extensive literature review was performed and a questionnaire survey was developed and used to gather relevant information. Input was solicited from all US State Departments of Transportation. Responses from 27 States revealed that transportation agencies currently rely on experience when selecting a bottleneck merge control strategy and often do not consider influence on construction activities. Thus, a gap was identified between bottleneck merge control and construction plans. Another gap was identified regarding the lack of formal criteria or guidelines for selecting a bottleneck merge control strategy. These gaps need to be addressed through investigating the influence of bottleneck merge control strategies on construction activities, and the development of formal criteria for effective selection of such strategies.