Potential Impact of Exempt Vehicles on HOV Lanes
This study was sponsored by the Federal Highway Administration (FHWA) to examine the potential impact of certain exempt vehicles on the operation of HOV facilities. This report is provided for use by state departments of transportation and other agencies in considering HOV exemption policies, as well as monitoring and evaluating the use of HOV lanes by exempt vehicles.
This report presents information on defining high-occupancy vehicle (HOV) lane capacity, options for using available HOV lane capacity, and analyzing HOV exemption policies. The use of HOV lanes by environmentally friendly vehicles, and law enforcement, emergency services, and public transportation vehicles is described, along with issues that may need to be considered when allowing these vehicles to access HOV lanes.
Chapter One presents the objectives of the study and provides background information regarding traffic congestion and the goals of HOV facilities in addressing congestion, mobility and air quality issues. The chapter outlines the activities conducted as part of the study, including research of federal and state legislation relating to HOV facilities and potential exempt vehicles.
Chapter Two defines the various types of HOV facilities and HOV lane capacity. The chapter presents options for using available HOV lane capacity, outlines the circumstances under which federal action is required to initiate changes in the operation of an HOV facility, and describes the federal review process and requirements based on FHWA Program Guidance on HOV Operations. The potential impacts of HOV exemption policies on traffic flow are explored.
Chapter Three examines possible HOV exemptions for environmentally friendly vehicles. Federal and state legislation and policies relating to HOV exemptions for these types of vehicles are described and the use of HOV lanes in California, Virginia, and other states by these vehicles is discussed. Potential issues to consider in enforcing HOV lane use by environmentally friendly vehicles are presented.
Chapter Four examines the potential effects of providing HOV exemptions for law enforcement, emergency services, and designated public transportation vehicles. Potential issues to consider in enforcing HOV use by law enforcement, emergency services, and designated public transportation vehicles are discussed.
Chapter Five provides a summary of the main points examined in the study and possible areas for further research. Topics for additional research focus on obtaining a better understanding of the potential impact of allowing exempt vehicles to use HOV facilities.