Signing and Pavement Marking for Concurrent-Flow High-Occupancy-Vehicle Lanes: Summary of Current Practice

Abstract

Concurrent-flow lanes account for more than half of existing high-occupancy-vehicle (HOV) mileage in the United States. Traffic on this type of HOV lane operates in the same direction as the adjacent traffic, typically in the far-left lane. Limited national guidance for signing or pavement marking is available that specifically addresses concurrent-flow HOV lanes. Therefore, the 13 states now using this type of lane have independently developed their own designs and standards. As a result, different signing and marking practices are being applied throughout the nation. Some of the signing and marking treatments being used on concurrent-flow HOV lanes in several states are documented. A summary of the current state of the practice on several signing and marking issues is included, on the basis of reviews of available design guides and project plans. The current standard practice is investigated, and the input of designers and state personnel is examined to determine the reasoning behind specific signing and marking treatments. General conclusions include the need for more specific direction on signing and marking practices to encourage uniformity. This step is desirable as more states begin to implement HOV-lane strategies to deal with urban congestion. The standards should be based on a merging of current practices and should be incorporated as a new section of an updated Manual on Uniform Traffic Control Devices. In addition, recommendations for specific design elements are presented.