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City of Seattle introduces Mercer Adaptive Signal System To Keep Traffic Moving

SDOT introduced a new adaptive traffic control system along Mercer Street between 3rd Ave W and I-5 which coordinates the operation of the traffic signals in and around the corridor to help vehicles move more efficiently. The system adapts to varying traffic conditions, such as congestion that may result from sports events, concerts or hour-to-hour traffic volume changes in the area.

The new system is called “SCOOT” which stands for Split Cycle Offset Optimization Technique. It is the first use of this type of adaptive signal system in the city.

“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.”

“We’re excited that SDOT’s Mercer Adaptive signal timing is expected to help travelers get through Queen Anne/South Lake Union more quickly,” stated Mike McQuaid, president of the South Lake Union Community Council. “South Lake Union is booming with new people working and living here, this will help keep people moving through one of the fastest growing neighborhoods in the city.”

SCOOT relies on equipment that detects vehicles at every lane at every intersection to determine traffic conditions. It predicts the flow of traffic and adjusts the amount of time available to each movement through the intersection to minimize overall delays in real-time, allowing for more effective signal operations in response to any changes in traffic as it occurs.

SCOOT details and benefits:

  • Installed along Mercer from 3rd Ave W to Fairview Ave N
  • Along the parallel corridors of Valley/Roy St from Fairview Ave to Queen Anne Ave N
  • At three additional intersections on Republican St
  • In total, 32 signalized intersections are operational with SCOOT in and along the Mercer corridor
  • Reliable travel times through the network
  • Enhanced transit operations
  • Reduced overall emissions and fuel consumption
  • Especially effective in situations in which traffic fluctuates due to special circumstances and/or special events

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