Program Spotlight

Latest updates on the Alaskan Way Viaduct Replacement Program

  • A tunneling breakthrough near the stadiums

    Seattle Tunnel Partners is preparing for Bertha to break through the southern wall of the SR 99 tunnel access pit, but another, lesser known tunneling breakthrough has already occurred approximately 2,000 feet south of the pit. Earlier this month, crews demolished the temporary wall separating two sections of cut-and-cover tunnel under construction to the west of the stadiums. A cut-and-cover tunnel is just what it sounds like – dig a trench, then build a floor, walls and a … more

  • New time-lapse video highlights crane construction

    Crews have spent the past several months assembling the massive red crane that will lift Bertha to the surface for repairs. As STP prepares to move the machine into the pit, crane crews are also making final preparations. We put together a new time-lapse video to illustrate how the crane came to be. This post explains the assembly process in more detail. Don’t forget about our time-lapse cameras, which will give you a good view of STP’s work to repair Bertha. … more

  • Information for residents and businesses in Pioneer Square

    Recently, our team detected approximately one inch of ground settlement near the pit Seattle Tunnel Partners is building to access and repair the SR 99 tunneling machine. Settlement was also detected on the Alaskan Way Viaduct and some of the buildings that we are monitoring; the amount of settlement lessens in the surrounding area. Our experts are still analyzing data and conducting daily inspections of the viaduct, but the initial settlement we reported publically on Dec. 5 has since … more

  • New pavement and walls add shape to the tunnel’s future north portal

    At the construction site for the SR 99 tunnel’s north portal, imagining the future is getting easier. While it all looks like one project, north portal construction is comprised of two separate contracts. Roughly everything south of the tunnel entrance near Harrison Street is part of the main tunnel contract being completed by Seattle Tunnel Partners. North of the tunnel entrance, crews working for Atkinson Construction are building the lanes and ramps  that will connect … more

  • Heavy lifting with some very big cranes

    Since SR 99 tunnel construction started, big cranes have become a familiar sight on the west side of the Alaskan Way Viaduct. Recently, two new cranes have risen up, and they are like redwoods in a forest of pine trees. The “little” crane can lift up to 300 metric tons and stands 180 feet high. Its big brother can lift up to 600 metric tons and tops out at 236 feet high. That’s more than four times the height of the viaduct, or about the same height as the clock tower … more

  • Bertha soapbox car on display now at Milepost 31

    She’s like Bertha, but faster. Much, much faster.

    Meet “Bertha’s Last Stand,” runner-up at the 2014 Red Bull Soapbox Race in Seattle. Though not affiliated with or supported by WSDOT, a group of soapbox racers from Machias, Washington were so inspired by Bertha that they designed and built their own soapbox tunneling machine to drill through the competition. One of 36 teams that built and raced homemade cars through Seattle’s Pioneer Square neighborhood, … more

  • Take a virtual tour of SR 99 tunnel construction

    Keeping the public informed about our work to replace the Alaskan Way Viaduct is an important part of what we do every day. Our goal is to give you as much access as possible to this amazing project, which is why we regularly post updates, photos and videos of our progress. We even offer walking tours from our information center, Milepost 31, to a viewing platform that overlooks the pit where tunneling began in summer 2013.

    Unfortunately, there’s one frequently received request … more

  • New narrated video explains Bertha repair work

    As reported elsewhere on our website, work to access and repair the SR 99 tunneling machine is coming along. We’ve heard from some people that Seattle Tunnel Partners’ repair plan is hard to picture. Enter STP’s Chris Dixon, who was nice enough to narrate a video that explains what crews are doing to resume tunneling by March 2015. Watch it on YouTube or download a WMV file.

    Other resources 

    Seattle Tunnel Partners repair work plan (pdf 4.8 Mb) … more

  • What we’re doing to keep traffic moving during the four-day SR 99 closure

    We’ve been asking you to do your part to reduce congestion when SR 99 closes for four days starting Friday night, Aug. 22. That includes things like changing your commute habits and choosing an alternate way to get around.

    But what are we, the agencies tasked with keeping traffic moving during this closure, doing to help? Quite a bit, actually. Here’s a roundup of some of the steps we’re taking to help you and your fellow commuters through the closure.

    Washington … more

  • Four-day SR 99 closure shines spotlight on tunnel’s north portal

    You may have heard that SR 99 will close for four straight days starting Friday night, Aug. 22. It’s the longest full closure of SR 99 in Seattle since crews demolished the southern mile of the Alaskan Way Viaduct in 2011. While this is probably not welcome news for travelers, it is a sign of progress at the tunnel’s north portal. 

    The 2011 demolition of the viaduct cleared the way for construction of the tunnel launch pit and the commencement of tunneling. During this … more