Skip to main content

City of Seattle implements SCOOT adaptive traffic management

Seattle Department of Transportation (SDOT) has implemented a new adaptive traffic control system at 32 intersections along Mercer Street between 3rd Ave W and I-5, which has been one of the city’s most congested corridors for over 40 years. Developed by the UK’s Transport Research Laboratory, the SCOOT (Split Cycle Offset Optimisation Technique) system coordinates the operation of the traffic signals in and around the corridor to help vehicles move more efficiently. SCOOT works in real-time to reduce delay
May 2, 2017 Read time: 2 mins
Seattle Department of Transportation (SDOT) has implemented a new adaptive traffic control system at 32 intersections along Mercer Street between 3rd Ave W and I-5, which has been one of the city’s most congested corridors for over 40 years.


Developed by the UK’s Transport Research Laboratory, the SCOOT (Split Cycle Offset Optimisation Technique) system coordinates the operation of the traffic signals in and around the corridor to help vehicles move more efficiently.

SCOOT works in real-time to reduce delays and adapt to changing traffic volumes, such as congestion caused by nearby sport or concert events. The system detects cars in each lane at every intersection. It determines traffic levels, predicts the flow of traffic and adjusts the amount of time available to each movement through the intersection. The result is more effective and responsive signal operations. SCOOT provides significant benefits:

• Quicker, more reliable travel times through the network
• Enhanced transit operations
• Reduced overall emissions and fuel consumption
• Effective management of traffic fluctuations due to special events

To assess the how well SCOOT is working, vehicle data is being collected daily and compared to historical averages. Reporting periods include the three-hour morning and evening peak travel times in both the eastbound and westbound directions during the five-day working week. From the data received to date, drivers travelling east during peak times are experiencing a six per cent increase in morning travel time reliability and 38 per cent in the evenings.

“This new system will adjust signal timing based on traffic in and around Mercer in real time. We know Mercer is the busiest corridor in the city,” said SDOT Director Scott Kubly. “SCOOT will help reduce the traffic backups we’ve seen along Mercer and help keep people moving.”

Related Content

  • Veolia Transdev and IBM collaborate to improve urban transport in cities
    June 27, 2012
    Veolia Transdev and IBM today announced that together they are developing a smarter mobility solution designed to help cities alleviate road congestion, optimise transportation infrastructures and improve the urban traveller experience. The first application of the smarter mobility solution is being piloted in the city of Lyon, France, which is the second largest metropolitan area in the country outside of Paris, as part of the city’s Optimod project. Optimod'Lyon will test and validate new services to impr
  • Smart parking technologies: solving drivers parking pain
    March 30, 2017
    Smarter parking can benefit city authorities and other road users as well as drivers looking for a space, argues Dr Graham Cookson. As witnessed by the recent announcements at the Consumer Electronics Show, the automotive industry continues to focus on the driving experience; moving from speed and handling towards safety and efficiency.
  • Inrix aids authorities in dealing with data
    August 18, 2015
    New traffic data products and services have been launched to aid transport and urban planners and business with detailed intelligence on journey patterns, reports Jon Masters. Manual travel surveys ought soon to become a thing of the past for transport planners and the business community. The technology now exists for getting sophisticated levels of traffic and trip data from connected vehicles. Cars and commercial fleets carrying a GPS device, or a mobile phone or smartphone are the sources of the informat
  • Data helps Ohio DoT get grant money
    January 25, 2022
    Ohio Department of Transportation turned to StreetLight Data when it needed to finalise grant money for a key infrastructure link. David Crawford sees how metrics brought in the cash…