SEATTLE — South Dearborn Street in Seattle is open to drivers after demolition of the Alaskan Way Viaduct in that area wrapped up earlier than expected. 

The Washington Department of Transportation closed South Dearborn Street and narrowed First Avenue South to two lanes on Sept. 12 to give demolition crews access to one of the final pieces of the Alaskan Way Viaduct. 

The work was expected to last until Sept. 22, but crews finished the job early.

"Demolition crews made quick work removing the section of the Alaskan Way Viaduct above South Dearborn Street, one of the structure's last remaining sections," said a WSDOT spokesperson. 

WSDOT released video showing a timelapse of the demolition that took less than a week to complete. 

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With the South Dearborn Street viaduct section gone, that leaves only one remaining span of viaduct along Seattle's waterfront. 

Starting at 4 a.m. Wednesday, Sept. 18 Alaskan Way will be narrowed to one lane in each direction near Marion Street, so demolition teams can access that final section. 

Later this week, WSDOT crews will also stripe a bus-only lane on northbound SR 99 between South Spokane Street and South Dearborn Street. 

This lane existed during SR 99 tunnel construction and helps ensure reliable trips for King County Metro buses carrying about 30,000 passengers a day into downtown, WSDOT said. 

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The bus lane is scheduled to be in place by Sunday, Sept. 22 but the work is weather dependent. 

King County Metro's northbound buses will remain on temporary reroute until the start of service on Sunday, Sept. 22.