Safer roads mean less congestion

The project is designed to improve traffic safety and highway efficiency in one of the state’s busiest corridors. Fewer collisions mean less congestion, especially on this stretch of highway where collisions account for as much as 70 percent of congestion.

The speed-limit signs also will alert drivers with a lighted arrow to warn of an approaching lane closure and a red ‘X’ at the closed lane to better manage blocking incidents.

Drivers will see varying speed limits, alerts or even blank signs, depending on traffic conditions. Electronic signs will display traffic alerts and information, such as backups and incidents ahead and alternate route suggestions.

New highway sign technology

* WSDOT installed 15 new sign bridges, or gantries, between the Boeing Access Road and I-90 on northbound I-5.

* Sign bridges will support electronic lane status and speed-limit signs over each lane and electronic message boards that warn of backups ahead.

* Signs will be linked to traffic sensors that record traffic speed and volume used to determine the speed limit.

* The Washington State Patrol will enforce speed limits as displayed.

Smart highways

WSDOT crews will install other intelligent transportation system (ITS) components to improve conventional signs along the roadway. All of this technology is included in WSDOT’s smart-highways approach, widely known as active traffic management (ATM).