SDOT director happy review shows traffic signals 'trending toward failure'

SEATTLE — KIRO 7 was first to report that 70 percent of Seattle traffic signals have equipment in poor condition and that the system is trending toward failure.

On Tuesday, SDOT Director Peter Hahn told KIRO 7 he’s happy the problems came to light.

A city audit revealed that traffic lights at 42 intersections went into flash mode because of failing equipment.  The report says the failures cause “increased traffic congestion, delays, and potentially accidents.”  And the city could be on the hook.

On Tuesday, Hahn pointed the blame at the traffic signal system from 1985.  He told the city council transportation committee that it desperately needs updating.

“It's an investment other cities have made and we should be there,” said Hahn.  He blamed the light failures on current staffing levels saying it's hard to keep up with repairs on the old system.

And it explains a frustration drivers may have had: Lights that don't always seem timed to traffic.  Currently lights are timed based on traffic counts taken over a few days.

The new technology SDOT wants would involve digging under the streets and putting wires underground.  The wires could track cars as they move down the road.  The system would then adjust the traffic signal timing in real time as traffic builds.

“Surely, it'd be better to have a system responsive to traffic,” said Hahn.  “And even better, a system responsive to not just traffic, but by the kind of traffic whether it's transit, pedestrians, and by lane.”

A new system would cost tens of millions of dollars, but it could be done piece by piece.  It will be up to the mayor and city council to fund it in the budget.

And realistically it wouldn't solve all the gridlock.  Hahn estimates it would shave seconds off of a minute long drive, a 5-10 percent improvement.

“But five or ten percent improvement when you're counting cars in our great economy, that's a pretty good improvement,” said Hahn.

A new traffic signal system wouldn't happen overnight.  In the meantime, SDOT is considering adding message signs to alert drivers of trouble spots to avoid.

KIRO