The King County Road Services Division will begin work Tuesday, Aug. 3 to improve the seismic stability of the Upper Tokul Bridge, located on Tokul Road Southeast over Tokul Creek near Snoqualmie.

The construction work is expected to last five to six weeks, and at least one lane on the bridge will remain open to traffic during the project. But, the work will create a rough road surface, and motorists – particularly motorcycle riders – are urged to slow down and use extreme caution when crossing the bridge.

Traffic across the bridge will be limited to a single lane during the six-week construction period, and temporary all-way stop signs will be installed to control travel across the bridge. Signs will be posted warning drivers of the hazards.

The 40-year-old concrete bridge will be reinforced to help it better resist lateral movement during an earthquake. The most noticeable work involves removing the existing asphalt pavement and installing metal plates on the bridge deck. In addition, both ends of the bridge will be excavated to place reinforcing steel and concrete on the approaches. Other work will occur on the underside of the bridge. Total project cost is $600,000.