Police say the driver of the truck that hit the bridge stayed at the scene and is cooperating with authorities. He is reportedly a professional truck driver from Alberta, Canada.
More than 67,000 drivers use the bridge every day, the Washington State Department of Transportation said Friday, and it is encouraging people to avoid the area while the National Transportation Safety Board inspects the wreckage.
The Seattle Times reports that it will take "weeks at the very least" to repair the bridge, citing a state transportation department spokesman. The bridge, built in 1955, was inspected twice and received minor repairs in the last year, the state transportation secretary said.