General Guidelines for Active Traffic Management Deployment

Project Description

While popular in Europe, only a handful of U.S. states have deployed an active traffic management (ATM) strategy. This report provides guidelines on ATM strategies for transportation agencies to implement. ATM?including shoulder use, speed harmonization, queue warning, dynamic merge control, dynamic rerouting, and dynamic truck restrictions?increase capacity and safety on motorways without having to widen them.

Shoulder use for all vehicles allows all drivers to use the designated shoulder when open, as indicated by traffic control devices. Transit-only shoulder use allows only transit vehicles to use the designated shoulder under specific conditions. Speed harmonization is an operational strategy where agencies monitor data coming from field-deployed sensors on a roadway and proactively and automatically adjust speed limits when congestion thresholds are exceeded and congestion and queue formation are imminent.

Based on dynamic traffic detection, queue warning informs travelers of the presence of upstream queues, using warning signs and flashing lights. Dynamic merge control closes specific lanes upstream of the interchange to manage access based on traffic demand. Dynamic rerouting and traveler information consist of redirecting traffic to avoid unequal levels of service on parallel routes, providing users with viable route alternatives and helping reduce the impact of noncurrent congestion. Dynamic truck restrictions require all truck traffic to use designated lanes during peak periods. The intent is to increase the homogeneity of speed on each lane and to minimize the disruption in traffic flow caused by heavy vehicles.

For More Information