Washington State currently has 52 permanent-scale weigh stations. Sixteen are located on interstate highways. Permanent scales are equipped to detect axle, tandem, and gross weight violations. The Ports of Entry (POE) at Ridgefield, Bow Hill, Plymouth, and Spokane operate 24 hours per day, seven days per week, as does the scale site at Cle Elum, which also serves as an interior POE for traffic east and west bound on I-90.
Map of Weigh Stations
Source: WSDOT Systems Analysis & Program Development
Plug-and-Run Sites
Plug-and-Run sites exist where enforcement officers operate full-sized vans equipped with a desk and work area. They enter the scale site, remove the scale head from the pedestal, activate an electronic sign, and begin the weighing process. These sites enable officers increased mobility from site to site. Currently, Plug-and-Run sites are operational on SR 395 in Spring Valley, SR 99 in Federal Way, SR 12 in Naches, and SR 395 in North Pasco.
Preliminary engineering and potential site selections are underway for a Plug-and-Run site in the Spokane area.
Weigh-in-Motion (WIM)
The Commercial Vehicle Information Systems and Networks (CVISN) transponder program allows trucks to bypass weigh stations by electronically verifying a truck's legal weight and credentials as the truck continues down the road at freeway speeds.
Weigh-in-Motion technology is used to expedite the weighing process for trucks. With transponders, trucks can bypass a weigh station by electronically verifying a truck's legal weight and credentials while the truck continues down the road at freeway speeds.
Source: http://cvisn.wsdot.wa.gov/
Washington State currently has eight operational WIM sites at: Everett, Ridgefield, Bow Hill, Ft. Lewis, Stanwood/Bryant, Cle Elum (Westbound), Federal Way (both Northbound and Southbound). Two more sites are scheduled to be deployed by July 2005 at: Kelso (Southbound I-5) and Plymouth (Westbound I-82).
Source: Officer John Nicholas, Washington State Patrol