The new device can be installed in more places and collect better information for commuters, and the first batch of pucks is ready to be put in place.
At the department's traffic headquarters, DOT workers keep close tabs on how drivers move around Western Washington. A good chunk of that information comes from traffic sensors out on the highways, but department officials want to upgrade those devices.
That's exactly what they're doing with a new device, which is about the size of a hockey puck and is supposed to glide around the ice.
Engineers say the high-tech little Sensys Pucks have built in wireless sensors that can count every vehicle that drives over it. The pucks measure speed, how many cars are in a given lane, gaps in between vehicles and even the length of cars and trucks.
Starting Monday night, 17 of the new sensors will be dropped into a stretch of the northbound lanes of I-5 near Northgate Mall. Four-inch holes have been bored into the pavement and are ready to be sealed into position with a strong epoxy.
Traffic officials say the current inductive loop system needs to be connected to a hard-wired controller unit, and that only works well when roads are in good condition.
The new pucks can be installed in places where the driving surfaces have taken a beating, which is an important condition these days.
"They work when the pavement is broken, and we're really trying to be proactive, looking into the future, realizing our revenue package is very small. And we're going to have to come up with the new ways to detect traffic, " said WSDOT traffic engineer Dina Swires.
Department officials say head-to-head, side-by-side testing in the coming months will be crucial. Any information that's gathered out on the roads will help better evaluate traffic flow to let drivers know if there are major backups ahead or if new trouble spots have popped up.
The Northgate project costs about $20,000, while a comparable system using the current loops method would run about $15,000, according to WSDOT officials.