Signal Timing Optimization Methodologies and Challenges for the City of Baltimore, MD, USA, Central Business District and Gateways.

A major signal timing optimization project was recently completed in Baltimore, Maryland. This article discusses the challenges of this 425-signaloptimization project, as well as the methodologies used to overcome thesechallenges. The project involved 250 signals in a grid central business district (CBD) and 175 signals on gateway corridors leading to and from the CBD. Much of the success of the project can be attributed to a computertool for signal timing analysis and optimization. Using the traffic signal timing model, multiple users could code the network, perform independent signal timing evaluation and subsequently merge the files to a single working file. The associated microsimulation software allowed engineers to develop and visualize alternative offset and split solutions and corresponding progression plans. The project paid for itself in less than 3 monthsin terms of reduced delays, stops and emissions.