WSDOT drone video shows Seattle’s SR 99 tunnel progress

Seattle — The Washington State Department of Transportation released a drone video showing two miles of ongoing construction work inside Seattle’s SR 99 tunnel. Now that the tunneling machine Bertha’s work is complete, it’s possible to fly a drone with a video camera from end-to-end inside the tunnel. The upper roadway of the tunnel’s double-deck highway is more than 85 percent complete. Installation of the lower roadway and all the systems it takes to operate a modern tunnel is now underway.