Advisories/Updates

  • Feb. 26 project update: Bertha‚Äôs next move

    After taking a break from mining to clean up the mixture of dirt, concrete and water that came into the access pit during last week’s breakthrough, Seattle Tunnel Partners has resumed Bertha’s final approach into the pit. 
     
    Because the cutterhead has made it through the pit wall, there isn’t any digging left to do. The focus now is on building the concrete tunnel rings that enable the machine to move forward. Bertha must build five more rings – a process that’s explained visually in this animation (links to YouTube) – before she comes to rest near the northern edge of the pit. Bertha will continue to take breaks so crews can clean up debris.
     
    When the machine reaches its destination, crews will begin disassembling the machine and preparing to lift pieces to the surface for repair. STP has said this process will take significant time and effort because it involves a number of steps. These steps include:
     
    • Installing work areas around the machine
    • Disconnecting joints, cables and hoses
    • Removing cutting tools and other parts from the cutterhead
    • Welding lift points on the body of the machine


    When the disassembly process is complete, a massive red crane (links to YouTube) will move into position. Several pieces of the machine will be removed from the pit before the cutterhead, as illustrated in STP’s repair video (links to YouTube). 

    We’ll continue to keep you posted as STP’s work moves forward. Remember to visit our access pit camera and follow Bertha on Twitter for the latest information.
     

    Crews clean up debris in the access pit.
     
    Repair plan resources:

     

    Previous updates

    Feb. 20, 2015 afternoon update - Tidying up the launch pit

    Feb. 19, 2015 morning update - Bertha reaches daylight

    Feb. 19, 2015 morning update - Bertha approaching the pit

    Feb. 18, 2015 afternoon update - Bertha digs on

    Feb. 18, 2015 project update - Bertha on the move

    Archive of previous updates

     

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  • Feb. 20 update: Tidying up the access pit

    After a few days of steady digging, Seattle Tunnel Partners is taking a break from mining so crews can clean out the bottom of the access pit. As expected, a mixture of dirt, concrete and water came into the pit along with the tunneling machine during Thursday’s breakthrough. Crews are using vacuum trucks and other tools to remove the material. 
     
    Once Bertha’s cradle is cleaned off, crews will continue moving the machine forward. Bertha must travel an additional 35 feet before STP and manufacturer Hitachi Zosen can begin the disassembly process. Since mining resumed late Tuesday, Bertha has moved nearly 22 feet.
     

    Repair plan resources:

     

    Previous updates

    Feb. 19, 2015 morning update - Bertha approaching the pit

    Feb. 18, 2015 afternoon update - Bertha digs on

    Feb. 18, 2015 project update - Bertha on the move

    Feb. 13, 2015 project update - Safety at the forefront

    Feb. 13, 2015 project update - Long-term traffic impacts on SR 99: lane closure begins March 7 through late May

    Feb. 12, 2015 - Incident at tunnel's north portal work zone

    Feb. 9, 2015 project update - Cradle awaits Bertha's front end

    Archive of previous updates

     

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  • Reminder: Long-term traffic impacts on SR 99 begin on Monday, March 9

    In one week, beginning Monday, March 9, crews building the future north portal of the SR 99 tunnel will close a single lane in both directions of SR 99/Aurora Avenue North between Valley Street and the Aurora Bridge. Two lanes will be open in each direction while crews install foundations for four large sign structures in the median and curb areas.

    Closure details and schedule

    Work is planned in two phases, starting with overnight lane closures on Monday, March 9 to set up the work zone. View a map of the work locations. 

    • Monday night, March 9
      • Beginning at 8 p.m., up to two lanes will be closed in both directions between Valley Street and the Aurora Bridge
      • Beginning at 10 p.m., SR 99/Aurora Avenue North will fully closed in the northbound direction between the south end of the Battery Street Tunnel and Valley Street
    • Phase 1 (approximately 8 weeks): one lane closed in both directions for median work
      • One lane in the northbound and southbound directions will be closed around-the-clock while crews install four sign foundations in the median
    • Phase 2 (approximately 4 weeks): one lane closed in southbound direction for curb work
      • One southbound lane will be closed around-the-clock while crews install two sign foundations in the southbound curb area

    Durations shown for each phase are approximate and may change due to weather or other factors. We will keep the public informed as we prepare for Phase 2 work.

    Bus rider information

    Because northbound and southbound buses will travel, and stop, in the outside lanes with other vehicle traffic, trips into and out of Downtown Seattle may take longer than normal. During both phases the southbound bus-only lane restriction will be lifted.

    Night work and weekend lane closures

    In an effort to balance the needs of drivers and residents, an additional lane may close in both directions at night and during some weekend days. Some of this work is unavoidably noisy and may be disruptive. Residents with concerns related to nighttime noise may call 206-305-6967.

    Driver tips

    The long-term lane closures are expected to cause additional backups on SR 99 for vehicles and buses, particularly during peak commute times. WSDOT is encouraging drivers and bus riders to: 

    • Allow plenty of extra time and expect additional congestion, especially during peak commute times, on SR 99 between the Aurora Bridge and downtown.
    • If possible, consider leaving early, delaying your trip or telecommuting to avoid traveling during peak commute times in the morning and afternoon.
    • If you must drive, know before you go and use WSDOT's travel tools or visit SDOT’s travelers information page.
    • Share a ride in a car- or vanpool, or walk or ride a bicycle.

    Questions?

    Contact us at viaduct@wsdot.wa.gov or 1-888-AWV-LINE (298-5463) or visit us at www.AlaskanWayViaduct.org

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Program Spotlight

  • 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