Spokane Street Viaduct Widening Project: Project History

Seismic Retrofit (1998-1999)

Addressing safety issues first, the viaduct was seismically retrofitted to improve the viaduct's ability to withstand an earthquake.

Photos taken after the retrofit, showing reinforced column bases and steel jackets

Median Barrier Installation (1999)

Continuing to address safety issues, SDOT next installed a median barrier down the center of the viaduct. The barrier divides the two directions of traffic and all but eliminates the possibility of head-on collisions.

Median barrier

Lower Roadway Utility Relocations (2003)

In 2003, SDOT relocated utilities at the street level to make room for the viaduct widening itself. The project included drainage, water and sewer lines, Seattle City Light electrical utilities, and improvements to the City's traffic signal system.