Snoqualmie pursues creation of westbound on-ramp from Parkway to I-90

Snoqualmie has asked WSDOT to convert the weigh station to a dedicated I-90 on-ramp.

By Evan Pappas • November 2, 2018 1:30 am
An example of the diverging diamond used in WSDOT’s explanation of the design. The video is part of Mayor Matt Larson’s interchange update video available on the city’s YouTube channel. (Courtesy Photo)
An example of the diverging diamond used in WSDOT’s explanation of the design. The video is part of Mayor Matt Larson’s interchange update video available on the city’s YouTube channel. (Courtesy Photo)

The Snoqualmie City Council and mayor have sent a letter to the Washington State Department of Transportation asking them to convert a part of the weigh station at the Interstate-90, state Route 18 interchange, to a dedicated on-ramp from Snoqualmie Parkway directly to I-90.

The I-90 and SR 18 interchange is currently undergoing environmental and traffic analysis for the upcoming interchange improvement project. The interchange is planned to be reconstructed in a “diverging diamond” design in order to improve flow and safety of the traffic that travels through it. The interchange is also the location of a weigh station for passing trucks and commercial vehicles.

In their letter, the city is asking WSDOT to convert part of the weigh station into an on-ramp from the city’s Snoqualmie Parkway directly onto I-90 so westbound commuter traffic does not back up into the city, as is currently the case.

“We are writing to urge WSDOT to promptly relocate the weigh station and use a portion of this area to allow for a temporary and designated on-ramp feeding directly off Snoqualmie Parkway onto westbound I-90 during the DDI (diverging diamond interchange) construction,” the letter reads.

“This is consistent with WSDOT’s stated commitment to make low-cost improvements that would manage congestion in the interim while interchange improvements are being completed, because it would alleviate the current significant backups on Snoqualmie Parkway while also allowing for more efficient vehicle movements from northbound SR 18 onto the existing westbound I-90 on-ramp. These improvements would quickly improve safety conditions while also benefiting thousands of drivers every day, even before construction of the physical interchange improvements has begun.”

The city acknowledged that WSDOT had planned to use the weigh station as a staging area for the construction, but writes that an on-ramp use would not remove the ability to use the rest of the space as a staging area and notes that the weigh station is not the only possible location for a staging area. The city also offered to work with WSDOT to meet their construction staging needs.