Work on the Spokane Street Viaduct Widening Project remains on schedule, with the focus for 2011 on completion of the new First Avenue S on/off-ramp as well as the new widened portion of the upper roadway. Crews are building the upper deck out 41 feet to the north – and of course building support columns along the way. Then, as columns are finished, crews remove the temporary supports, called “false work” (no, that doesn’t mean it wasn’t real work…) because it’s not the final product, and the weight of the new portion of upper roadway shifts onto the newly built columns.
More than half of the columns needed to support the new widened portion of the upper roadway (there are a total of 154 in the design) are now complete. Other project progress includes completion of nearly three quarters of all support shafts (these anchor the columns) and near completion of the “deck pour” (concrete surface of upper roadway) from Fifth Avenue to Second Avenue. Plus, work is progressing nicely to construct the new First Avenue S on/off-ramp as you can see here..
Once the new First Avenue S on/off-ramp and the newly widened portion of the upper roadway are finished, traffic can shift to the new structure and crews will begin work to improve the existing S Spokane Street Viaduct (West Seattle Bridge) currently in use. Overall completion of the project is set for spring 2012.
One other update – expect Fourth Avenue S to be restored to two lanes in each direction by March, after all intersection work is complete. After that only occasional short-term lane restrictions are expected on that roadway.