A new congestion-reducing ramp configuration for northbound Interstate 5 drivers in Centralia is now open to traffic.
Washington state Department of Transportation contractor crews opened the new I-5 ramp Wednesday. The ramp combines northbound traffic entering from Mellen Street with traffic exiting to Harrison Avenue. Drivers will be able to travel between the two interchanges without merging onto the interstate.
The changes are intended to reduce backups on the freeway and eliminate merge-weaving.
Crews closed the existing northbound Mellen Street on-ramp to I-5 and shut down the existing northbound off-ramp to Harrison Avenue by shifting traffic to the new, permanent configuration.
Northbound travelers exiting at Harrison Avenue will now do so south of the Skookumchuck River Bridge. The northbound drivers entering the interstate will continue through Harrison Avenue to the on-ramp past the Harrison Avenue intersection.
The I-5 Mellen to Blakeslee Junction project, expected to cost $128 million, will reduce congestion and improve safety on I-5 through Lewis County by adding local highway lanes alongside the intersections while modifying interchanges at Harrison Avenue and Mellen Street.
Construction should be complete next year.
The next steps of the project will include several traffic shifts on I-5 in Centralia until the project is completed. In the fall, both lanes of northbound I-5 will shift between Mellen Street and Harrison Avenue. Contractor crews will modify and repair the overhead steel truss of the Skookumchuck Bridge to an even height across all lanes.
The speed limit will be reduced to 50 mph through the project area.