Traffic Signal Upgrades

Traffic Signal Upgrades

updated on 8/2/2021

New timings deployed at five Central Avenue and Durham Road traffic lights

Traffic engineers deployed new signal timings on Monday, Aug. 2, along the congested stretch of Central Avenue/Durham Road and seek driver feedback about the timing changes.

The five intersections on Central Avenue/Durham Road, which includes the Exit 7 interchange of the Spaulding Turnpike, is the first signal system to receive new traffic signal timings. New timings will be deployed to traffic signals systems at Weeks Crossing, north Central Avenue (Morin Street to Oak Street), and Silver Street (Central Avenue to Arch Street) in the coming months.

Once deployed, Sebago Technics engineers will monitor traffic flow and adjust timings based on traffic flow data and public feedback. For the Central Avenue/Durham Road corridor, engineers plan further adjustments when the new school year begins. 

Engineers request drivers to note any changes they see on Central Avenue/Durham Road beginning Monday, Aug. 2, and provide feedback at Feedback can be as simple as, “It seems better,” or, “I experienced less delay this morning while exiting Mill Street.”

Engineers had planned to deploy signal timings changes this spring but were delayed when it was determined a new fiber optic line needed to be installed to the city’s central traffic server.

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About the project

In partnership with the Federal Highway Administration (FHWA) and the New Hampshire Department of Transportation (DOT), the City of Dover has installed innovative technologies at 17 intersections within the Central Avenue corridor to coordinate traffic signals and improve traffic flow.

The $811,875 project is made possible from $649,500 in grants from the FHWA’s Accelerated Innovation Deployment (AID) Demonstration Grants Program administered by the DOT and a 20 percent match from the City of Dover, totaling $162,375. The FHWA grants were approved by Governor and Executive Council, DOT and Dover City Council. FHWA’s AID Demonstration Program provides funding to accelerate the implementation and adoption of innovation in highway transportation.

See a video of the project here:

Traffic signals at 17 intersections within Dover’s Central Avenue corridor are now connected wirelessly to the City’s central traffic server that consistently monitors traffic flow within the system and notifies staff when an issue arises along the corridor. The new technology also provides the ability to make real-time traffic signal programming changes within the system based on current conditions.

“We’re excited about these new technologies,” said City of Dover’s Deputy Community Services Director Bill Boulanger, who is managing the project. “It’s going to allow us to improve traffic flow, reduce congestion, and make on-the-fly changes to respond to whatever is happening on our roads. We think it’s going to be a success, and drivers will see a noticeable difference.”

The City of Dover worked with its traffic engineer partner, Sebago Technics of South Portland, Maine, and DOT, to secure the grant. The City of Dover has also contracted with Sebago Technics to deploy the new traffic technologies, assist with data collection, and optimize signalization throughout the corridor. The Automated Traffic Signal Performance Measures (ATSPM’s) will be the first deployed in the state and within Northern New England.

At several intersections, old-fashioned “loop sensors” were replaced with bell cameras and other optical sensing devices. The loop sensors could only detect the presence of perhaps a single vehicle, but the advanced optical sensors will now be able to determine how far back cars are stacking up at an intersection. Part of the project’s goal is to implement proven innovative strategies and methodologies for reducing the labor involved in managing the City’s traffic signals on the north-south Central Avenue artery through automation. Traditional traffic signal timing optimization involves counting traffic volume over a few days and using that data to create the appropriate timings. The process is labor-intensive, expensive, and the deployed signal timing is stagnant and can quickly lose its effectiveness as traffic volumes change. The new system will allow for continuous monitoring and adjusting.

The newly deployed technology includes new traffic signal controllers, vehicle and pedestrian detection equipment, travel time recording devices and communication upgrades. It will allow the City to accurately count vehicles, including a breakdown of cars and trucks, how long vehicles are stopped at traffic lights, and travel times through the corridor. Part of the enhancements also includes integrating the City’s central traffic management system with the DOT’s. That will allow the DOT to deploy emergency signal changes to aid traffic flow along the corridor in the event of a significant traffic accident on the Spaulding Turnpike.

The 17 intersections are part of four subsystems within the Central Avenue corridor: Week’s Crossing with four signals; five signals along northern Central Avenue from Morin Street to Oak Road; three signals along the Silver Street subsystem; and five signals at the Central Avenue/Durham Road subsystem, which Boulanger called the City’s most complex with 28,000 cars passing through the quarter-mile subsystem that includes two Spaulding Turnpike off-ramps, an emergency room and multiple schools within a short distance from it.

Over the next year, staff from the City of Dover and Sebago Technics will monitor traffic data and implement new traffic signal coordination programming throughout 17 signalized intersections along the Central Avenue corridor. As part of the ongoing implementation, drivers who use the corridor are asked to provide feedback about how these efforts are improving traffic flow.