The Seattle Department of Transportation (SDOT) announces the next full weekend closure of SR 99 on Oct. 4-7 for construction activities associated with the West Phase of the Mercer Corridor Project. Please note: this closure is being coordinated with the Washington State Department of Transportation for their semi-annual inspection of the Alaskan Way Viaduct.
On Friday, Oct. 4, Mercer Corridor Project crews will begin work on SR 99 including the installation of an underground water line and stormwater improvements. SR 99 will be fully closed to traffic beginning Friday, Oct. 4 at 11 p.m. to Monday, Oct. 7 at 5 a.m. During the closure:
- SR 99 will be fully closed to traffic between Valley Street and the southern end of the Battery Street Tunnel. Traffic traveling through Seattle via SR 99 will be directed to I-5 in northern Seattle at North 85th Street or in southern Seattle at East Marginal Way South and South Spokane Street. More information about alternate routes during construction may be found at: http://www.seattle.gov/transportation/mercercorridor.htm.
- Mercer Street, Broad Street, and the I-5 on- and off-ramps at Mercer Street will remain open during the weekend work.
- Pedestrian access will be maintained on the south side of Mercer Street between Fifth Avenue North and Dexter Avenue North or via Broad Street.
Early warning signs will be available in advance of the SR 99 lane restrictions. Travelers can expect significant traffic and delays and should plan ahead and use alternate routes.
Please note: The Washington State Department of Transportation will be holding their semi-annual inspection of the Alaskan Way Viaduct on Oct. 5 and 6 and associated closures of SR 99 between South Spokane Street and the Battery Street Tunnel will also be in effect. For more information about these closures, please visit the Washington State Department of Transportation’s Alaskan Way Viaduct Replacement Project website at: http://www.wsdot.wa.gov/Projects/Viaduct/Traffic