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Seattle Downtown Traffic Signal Re-Timing Project

Do you feel you need to wait too long or that you stop too often for traffic signals in downtown Seattle? If so, you might be interested in this on-going Seattle downtown traffic signal re-timing project.

Traffic Signal re-timing2

2nd Avenue

Seattle’s signal lights were timed around 10 years ago, but rapid growth, significant construction activity, fast growing employment, increased biking and walking activity, and special events have caused new bottlenecks that can result in abrupt traffic backups throughout the city.

Second Avenue at University Street

2nd Avenue at University Street

Seattle Department of Transportation is studying overall metropolitan traffic patterns to determine the most efficient way to optimize 300 signals in the Central Business District. Traffic signal retiming is one of the most cost-effective ways to reduce delays for people driving, biking, and taking transit, thereby making our downtown streets safer and more efficient. Comprehensive signal retiming programs have documented benefits of 7 to 13 percent reduction in overall travel time, 15 to 37 percent reduction in delay and 6 to 9 percent fuel savings (Institute of Transportation Engineers, 2009).

The purpose of this project is to develop and introduce enhanced signal timing models that respond to real-time traffic volume fluctuations, incidents, special events and traffic condition on freeways. A unique element of this project is the inclusion of a system that will change signal timing patterns in response to current travel time data. This will improve travel times, freeway access, transit speed and reliability.

Downtown Traffic Retiming Map

Downtown Traffic Retiming Map

SDOT plans to implement and fine-tune the new signal timings at the end of 2015 and expects drivers to see an improvement in travel times through downtown at the beginning of 2016.