Multimillion-dollar speed limit signs could better ease congestion if speeds enforced, engineer says

The lead engineer behind multimillion dollar speed signs near Seattle says they’re not being used to capacity.

He says congestion could be eased if there was more enforcement of the speed limits.

The digital signs that hang above I-5, I-90 and SR 520 were installed by the Washington State Department of Transportation in 2010 for about $42 million.

Built to help drivers slow down for upcoming congestion and to avoid crashes, WSDOT says the variable speed limits have helped reduce collisions.

KIRO 7 talked to Eric Shimizu, the lead engineer who designed the system, the second of its kind in the US, modeled after those in Europe.

Shimizu believes if law enforcement more actively enforced the speed limits by ticketing those who went faster like Europe does with their system, when traffic is moving, congestion could be eased.

“There’s vertical challenges or horizontal challenges where you can’t really see over a hill, and so the intent is to slow people down in those areas, so there won’t be as many secondary accidents or rear-ends because they couldn’t slow down in time,” said Shimizu.

The state patrol does not keep statistics for infractions on the variable signs, but KIRO 7 pulled speed ticketing for east and westbound I-90 for mile posts between the signs for the past few years.

In 2014, there were 3,600 speeding tickets. Last year, only 2,600.