Case Study
City of Madison Adaptive Signal Control Deployment
The Challenge | The Solution | Results | Conclusion
Executive Summary
The City of Madison, Wisconsin—one of the fastest growing regions in the state—faced increasing congestion and safety challenges along key arterial corridors experiencing steady population growth and major reconstruction related detours. To proactively manage rising traffic volumes and improve corridor reliability, the City of Madison and the Wisconsin Department of Transportation (WisDOT) deployed the Centracs® Adaptive signal control system along the McKee Road/Fish Hatchery Road corridor, a primary alternate route during the multi year Verona Road (US 18/151) reconstruction project.
Leveraging a mix of advanced vehicle detection technologies, Centracs Adaptive enabled real time optimization of signal timing to reduce congestion, improve safety, and mitigate the impacts of significant bypass traffic. The deployment delivered immediate and measurable improvements, including substantial reductions in travel time, stops, and incident related delays.
The Challenge
Madison is a growing metropolitan area with a strong economic base, a major university, and a steady influx of new residents. These are actors that placed increasing pressure on the region’s roadway network. Since the 1970s, Madison has sustained an annual growth rate of approximately one percent, with projections indicating continued expansion. Seasonal and event driven fluctuations caused by the University of Wisconsin–Madison further strain the transportation system.
This challenge intensified with the launch of the Verona Road (US 18/151) Reconstruction Project, a two phase modernization effort designed to improve safety, reduce crashes, and enhance long term mobility. During construction, traffic needed to be diverted to the parallel McKee Road/Fish Hatchery Road corridor, a four mile stretch already operating near capacity.
Planners anticipated a 20 percent increase in traffic volume during peak construction periods. Historical crash data also showed that many collisions occurred at Verona Road intersections—highlighting the need for better, more responsive signal operations on nearby bypass routes.
To prevent severe delays and to maintain reliable travel for commuters, freight movement, and local traffic, the City and WisDOT required a solution that could adapt in real time to rapidly changing conditions.
The Solution
To prepare for the expected surge in traffic, Madison and WisDOT selected the Centracs Adaptive signal control system, a proven real time traffic optimization technology. Working alongside Strand Associates and Traffic Control Corporation (TCC), the project team carried out a staged deployment strategy:
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System Deployment Approach
- Initial corridor re-timing for 13 signalized intersections to maximize baseline efficiency prior to adaptive activation.
- Deployment of Centracs Edaptive across the McKee/Fish Hatchery corridor.
- Integration of a diverse mix of detection technologies, including:
- Inductive loops for advance detection
- Autoscope® video detection systems for stop bar and, in select locations, advance/departure detection
- Radar detection sensors to enhance reliability during weather and low light conditions
By blending multiple detection types, Madison created a robust data input environment capable of providing the precise volumes, occupancies, and flow characteristics required for optimal adaptive control.
Centracs Edaptive continuously analyzed real time conditions and automatically adjusted signal timing to optimize progression, reduce stops, and minimize delay even during dramatic shifts in corridor demand.
Results
The deployment delivered immediate operational improvements, validating the effectiveness of adaptive control in a complex, high-volume environment with significant construction detours.
Performance Improvements
- Up to 22% reduction in travel time along the corridor
- 65% reduction in stops, resulting in smoother and more predictable traffic flow
- Reliable signal performance across various weather and lighting conditions due to diversified detection technologies
These results, which are unusually high for a corridor that had recently undergone timing updates, demonstrate the value of real-time adaptive responsiveness in managing variable traffic patterns.
Incident Response Performance
A major test occurred shortly after deployment when the Beltline Highway was closed from 8:00–9:15 a.m. during peak travel. As a result, traffic volume increased by 40 percent on the McKee/Fish Hatchery corridor within minutes.
Centracs Edaptive immediately responded by adjusting timing parameters to accommodate the spike, allowing the corridor to maintain mobility and avoid gridlock. Travel times returned to normal within 30 minutes. This was an outcome that would have been unlikely under traditional fixed time operations.
Conclusion
The City of Madison’s deployment of Centracs Edaptive proved instrumental in maintaining reliable mobility during one of the region’s most impactful roadway reconstruction efforts. By leveraging advanced detection and real time optimization, Madison and WisDOT improved travel time, reduced stops, and enhanced the corridor’s resiliency during both planned and unplanned traffic surges.
This project demonstrates the effectiveness of adaptive signal control as a scalable, data driven solution for modern traffic management, particularly in fast growing communities facing fluctuating travel patterns and evolving operational challenges.