When will the viaduct be closed?

Tags: sr99

For the most part, SR 99 remains open during construction thanks in part to a construction bypass roadway that connects SR 99 in SODO to the viaduct along the waterfront. The viaduct is closed for two weekends a year – generally in the spring and fall - for inspection and maintenance. We also have a few planned closures due to construction activities such as when the tunneling machine tunnels beneath the viaduct. For any type of planned closure, we provide advance notice to the public so they can plan their trips accordingly.