New traffic system may help 'Mercer Mess'

SEATTLE — The Mercer Mess may soon be a little tidier.

Monday morning, the city is introducing a new adaptive traffic signal control system that could shave minutes off the drive between the Seattle Center and I-5.

In 2015, the Seattle Department of Transportation decided to upgrade the traffic lights with the new Mercer Street alignment.

The basic premise is the green lights will now continually adapt to arriving traffic, which means drivers will waste less time sitting at red lights, and will move through the corridor more efficiently.

The $13 million project, which is part of the $930 million Move Seattle property tax levy, coordinates the lights using computer software.

In times of light traffic, the system condenses the timing of the light cycle.

Mercer Street is the first of five corridors a year where the city is installing either adaptive signals or other kinds of signal re-timing.

In a similar project in Los Angeles, traffic times were reduced by 10 percent.

Bellevue already has nearly 200 intersections using adaptive signals.  When traffic is lighter, the system shortens the length of red lights 20 to 50 seconds.

Traffic experts say if the new signal system works as planned, the typical 7 a.m. backup to I-5 will be pushed back until perhaps 7:45 a.m. and major backups will clear up quicker.

We'll get a demonstration of the new system Monday at 11:30 a.m.

Cox Media Group