HOV Facilities Primer
High-occupancy vehicle (HOV) lanes are a strategy that local governments have employed to reduce traffic congestion. The idea is simple. Single-occupant vehicle (SOV) travel is wasteful, particularly at peak travel times. Restricting certain highway lanes to exclusive use by multi-occupant vehicles encourages carpooling, vanpooling, and transit bus ridership. The result is a familiar sight - congested traffic in the general-purpose highway lanes while vehicles travel near the speed limit in the parallel HOV lanes.
HOV lanes were introduced in the late 1960s. Major growth in the establishment of these facilities occurred in the mid-to-late 1980s and 1990s. With concerns about popullation effectively eliminating new highway construction in many metropolitan areas, some transportation agencies now view HOV lanes as the only way of adding highway capacity without compromising air quality. The U.S. Department of Transportation promotes HOV construction, providing financial assistance through federal-aid highway programs
History of HOV Facilities
(By Dr. Katherine F. Turnbull, Associate Director, Texas Transportation Institute)
High-occupancy vehicle (HOV) facilities have been part of the urban transportation landscape for the past 30 years. During this time, HOV lanes have had their share of proponents and critics. Recently some groups have argued that HOV lanes are outdated and no longer benefit the transportation system. Others continue to promote HOV facilities as one way to deal with increasing levels of traffic congestion in major metropolitan areas.
What have we learned about HOV facilities in the past three decades? Recent studies sponsored by the National Cooperative Highway Research Program (NCHRP), the Transit Cooperative Research Program (TCRP), and the Federal Highway Administration (FHWA) - as well as ongoing state and local monitoring and evaluation efforts - provide insight into what works and what does not work with HOV facilities, and what future trends might develop.
Most HOV projects are intended to improve the people-moving capacity rather than the vehicle-moving capacity of congested freeway corridors. As a result, common objectives for HOV facilities are to
•Increase the average number of persons per vehicle;
•Preserve the people-moving capacity of a freeway;
•Improve bus operations;
•Enhance mobility options for travelers
The travel time savings and improved trip reliability of HOV facilities provide incentives for individuals to change from driving alone to carpooling, vanpooling, or riding the bus.
HOV facilities come in all shapes and sizes, and no "one size fits all." Many of the early HOV lanes developed in response to specific issues and opportunities in congested freeway corridors. The opening of the bus-only lane on Shirley Highway (I-395) in Northern Virginia outside Washington, D.C., in 1969 and the contraflow bus lane on the approach to New York - New Jersey's Lincoln Tunnel in 1970 represent the first freeway HOV applications in the country. Both of these projects still serve significant volumes of commuters.
The development of HOV lanes in North America progressed slowly during the 1970s and early 1980s. Major growth occurred from the mid-1980s to the late 1990s. Currently, there are 96 HOV projects on freeways and in separate rights-of-way in 30 metropolitan areas in North America. These facilities account for approximately 2,000 centerline miles of HOV lanes. Major HOV systems operate in Houston and Dallas, Texas; Seattle, Washington; the Los Angeles and Orange County area and the San Francisco Bay region in California; the Newark, New Jersey, and New York City area; and the Northern Virginia, Washington, D.C., and Maryland region. Other facilities are in various stages of planning, design, and construction.