Ramp Metering and High Occupancy Vehicle Facilities: A Synthesis Study

Abstract

High Occupancy Vehicle (HOV) lanes and ramp metering have been implemented at several places in the country to improve traffic conditions on freeways. This report presents a comprehensive study of the state of the art and state of the practice of these facilities in the U.S. and their effectiveness in improving traffic conditions on the freeway. The various types of HOV facilities have been discussed along with other system components such as park-and-ride facilities, ridership programs, enforcement areas and policies, ingress/egress facilities. The cost of several HOV facilities in the country has been presented and a set of guidelines have been prepared that may be followed for the implementation of a HOV Lane Facility. A comprehensive review of the various ramp metering facilities in the country has been presented. The components of the ramp metering system, the physical infrastructure and the various classifications of the ramp metering algorithms have been discussed. The results of a feasibility study for the implementation of these facilities on I-70 in Indianapolis, between I-65 and I-465 have also been presented.