Applying Emerging Technologies for Approaching Smarter Traffic Signal Optimization Processes Resulted in a Benefit-Cost Ratio of 14:1 in Maryland.
Signal Timing Optimization Focused on the Eight-Intersection Riva Road Corridor in Annapolis.
Annapolis
Applying Emerging Technologies for Smarter Traffic Signal Optimization Processes
Summary Information
Traffic signal retiming and optimization typically occurs every three to five years, often triggered by public complaints or the natural life cycle of the timings. One of the biggest limitations in the traditional signal optimization process is the limited data from one traffic count and a few field observations that may or may not reflect true conditions. Anne Arundel County, Maryland, aimed to revamp the traditional process, with the goal of integrating ITS technology, executing the process remotely, adhering to a limited budget, and reducing the implementation timeline. For this project, Anne Arundel County incorporated Automated Traffic Signal Performance Measures (ATSPMs) into the signal optimization process for multiple corridors, including Riva Road.
METHODOLOGY
ATSPMs add high-resolution data-logging capability to existing traffic signal infrastructure and data analysis techniques.
- Clustering analysis and data fusion filtered out anomalies and identified the most common patterns for timing plans and incorporated different data sources.
- ITS technologies including ATSPMs, object-based detection analytics, Bluetooth/Wi-Fi readers, communication via fiber, and closed-circuit televisions allowed the County to complete the project remotely.
FINDINGS
- The benefit-cost ratio for the project was 14:1; the costs included one year of signal performance measures for all intersections and one year of continuous counts for three major intersections.
- Overall, the Riva Road corridor experienced a decrease in median travel time and an improvement in travel time reliability in both the AM and PM peaks.
- Split failures decreased at the three major intersections along the corridor. Split failures occur when a signal does not provide enough green time to serve all the vehicles waiting on a particular movement.
- Harry S. Truman Parkway – reduction of 50 percent eastbound, 37 percent westbound.
- Admiral Cochrane Drive – reduction of 7 percent eastbound, 8 percent westbound.
- MD 665 – reduction of 14 percent eastbound left turn, 34 percent westbound left turn.
- Estimated corridor savings for a one-year timeframe included user cost savings of $324,000 (17,200 hours of delay) and fuel cost savings of $48,000 (15,000 gallons).
