Impact of Truck Lane Restrictions on Traffic Operations

This paper describes how, beginning in 1997, the State of Virginia began restricting large trucks from the left lane of rural interstates with more than 3 lanes by direction. The goal of these restrictions was to try reducing the interactions between passenger vehicles and trucks, hopefully improving safety and mobility. In 2000 and 2004, these restrictions have subsequently been extended to other portions of Virginia’s interstate system. Despite the presence of the restrictions, Virginia has never analyzed their effectiveness in improving flow or safety. This paper describes an analysis of the operational impact of truck lane restrictions on Virginia’s interstates. Vehicle speed, headway, and classification data were collected on interstates throughout the state using a mobile video detection system. The effect of truck lane restrictions on compliance, level of impedance, and traffic flow were also analyzed. The results showed that truck lane restrictions produce some positive traffic flow benefits, although there were issues with compliance with the law at some of the sites.