How high-tech tools can improve commutes

Posted by Unknown in , on Thursday, October 15, 2009

By guest blogger Noel Brady

George Jetson would be jealous. Sure, he flew to work in a domed commuter pod, but could his skyway tell him where the congestion was before he was stuck in it? I think not. But that’s exactly what we’re working on for some of the busiest highways in the Seattle area.


Have you ever found yourself sitting in traffic wondering, “Where IS this traffic coming from? A wreck? Obama’s motorcade?” You don’t know whether it will clear up around the next bend or if there’s a mass evacuation you didn’t hear about.

Well, your commute is going to get a lot less mysterious with automatic, real-time traffic information and a congestion-alert system that brings you the 411 as fast as backups can start to form miles up the road. We’re calling it Smarter Highways.

Starting with I-5 and SR 520 in summer 2010 and then I-90 by spring 2011, new signs will warn drivers of slow traffic ahead to reduce the rear-enders that cause more than a quarter of the congestion on our busiest highways. The system will deliver the info automatically by calculating traffic data from sensors embedded in the pavement. The information will reach drivers faster than ever to make it easier to switch lanes or pick another route before getting caught in the bumper-to-bumper mess.

Soon we’ll begin installing 15 new sign bridges, spaced a half-mile apart, over the northbound lanes of I-5 from Boeing Access Road to I-90. They’ll support variable speed-limit and lane-status (arrows and Xs) signs over each lane and one large electronic message board at each location. So, what will this look like?

Sign progression of Smarter Highways:


Mile 1: When traffic flows freely, the variable speed limit signs are black.


Mile 1.5: Seconds after a collision occurs three miles up the highway, the speed limit drops and a sign warns drivers of backups ahead.


Mile 2: As vehicles approach the collision area, the speed drops again.


Mile 2.5: A mile from the trouble spot speed limit signs flash arrows intermittently. Green arrows instruct drivers to proceed in the their lane, and yellow arrows mean exit the lane as soon as safely possible, because the lane is closed or blocked ahead.


Mile 3: At the site of the collision, red X’s indicate which lanes are blocked.


Want to learn more? Check our information about  I-5  and SR 520/I-90 Active Traffic Management on our website. You can also download our Building Smarter Highways folio (pdf 2mb) and view our Building Smarter Highways video.

So hold on to your space helmet, Elroy! It’s going to be a smooth ride.

This entry was posted on Thursday, October 15, 2009 at 2:37 PM and is filed under , . You can follow any responses to this entry through the RSS 2.0. You can leave a response.