Document Type

Technical Report

Publication Date



Green starvation, Saturated intersections, VISSIM, Preemption, Priority

Digital Object Identifier (DOI)


Traffic congestion is challenging to resolve at closely spaced oversaturated intersections. This condition leads to underutilization of green time at upstream intersections due to queue spill back from downstream traffic signals (green starvation). The research team developed a microsimulation model near Texas A&M University campus to simulate a network of traffic signals which included a pair of closely spaced signals that experience the green starvation frequently. The research team investigated two treatments to alleviate this condition when a queue spillback was detected: one, a low-level preemption at one or both intersections and two, a preemption at one or both intersections to call the phases to meter or service the saturated link to clear the queues. The research team analyzed these treatments with various combinations using the simulation model. Based on the study, the research team recommends the scenario with a treatment at both closely spaced intersection with a 250 second reservice setting for preemption as the best alternative for addressing the queueing problem.

Policy brief.docx (742 kB)
Policy brief