milepost 31 – Page 2 – Alliance for Pioneer Square

Alaskan Way Viaduct Replacement Project Update – April 2014

Milepost 31 Events

First Thursday Speaker Series – Bertha and Progress on the SR 99 Tunnel Project

April 3, 2014
6 – 6:30 p.m.

You’ve been hearing a lot lately about our efforts to replace the State Route 99 Alaskan Way Viaduct. This is a big, complex undertaking. And as we all know, we’ve encountered some challenges. Join us this Thursday at Milepost 31 as speakers from WSDOT and our tunnel contractor, Seattle Tunnel Partners (STP), explain what’s being done to address these challenges and get Bertha, the SR 99 tunneling machine, moving again.

Speakers:

Matt Preedy, WSDOT’s deputy administrator for the Alaskan Way Viaduct Replacement Program
Chris Dixon, Seattle Tunnel Partners (STP) project manager

History Scavenger Hunt

April 19, 2014
1 – 4 p.m.

Join us at Milepost 31 for our monthly activity for kids. This month we’re hosting a scavenger hunt eggstravaganza (pdf 371 kb) to discover Pioneer Square’s rich transportation history. Hop on down with your family and friends to explore historic icons and hidden gems in Seattle’s oldest neighborhood. Test your knowledge, check out cool new Pioneer Square locales, and enter to win a grand prize furnished by the Alliance for Pioneer Square. Pick up your scavenger hunt kit at Milepost 31 between the hours of 1 and 4 p.m.

And don’t forget you can find regular updates about Bertha on Twitter by following @BerthaDigsSR99.

Alaskan Way Viaduct Replacement Project Update – February 2014

It’s been a busy start to 2014 with the opening of the South Atlantic Street overpass and crews working to get Bertha, the SR 99 tunneling machine, digging again. Here’s a recap of what we’ve been up to:

Milepost 31 Speaker Series: Learn about the South Atlantic Street overpass
On Monday, Jan. 27, we opened a new overpass to the west of Seattle’s stadiums, just south of Pioneer Square. The overpass allows traffic to bypass a busy railroad track that crosses South Atlantic Street. Before the overpass, train activity often blocked traffic for extended periods, which not only slowed truckers traveling to and from the Port of Seattle, but also created backups that stretched onto Seattle streets and Interstate 90. The overpass saves truckers as much as 20 minutes of travel time between the port and I-5 or I-90.

Visit Milepost 31 between 6 and 6:30 p.m. on Thursday, Feb. 6 to talk to staff about how the structure is changing traffic patterns in the area. Read more about the overpass here.

Further evaluation required before tunneling can resume
On Tuesday, Jan. 28, Seattle Tunnel Partners (STP) pushed the SR 99 tunneling machine – which had been stopped since Dec. 6 – forward approximately 2 feet. Moving the machine forward allowed crews to further test the functionality of the machine and determine if they could resume full-production mining. It also created sufficient space to build the next concrete tunnel liner ring on Wednesday, Jan. 29.

When the machine moved forward, crews saw indications of above-normal temperature readings in part of the machinery, similar to readings encountered before crews initially decided to stop mining on Dec. 6. On Wednesday, STP made adjustments and mined an additional 2 feet. The above-normal temperatures persisted, and STP made the decision to stop and perform further evaluations.

STP crews and tunnel engineers are operating the world’s largest tunneling machine in complex conditions. Although their investigations to date have provided a great deal of information, we will not be able to definitively identify the issue or issues facing the machine until tunneling experts complete their review. We will provide additional information as it becomes available.

Please visit our webpage for regular updates.

Watch the Alaskan Way Viaduct Replacement Project on YouTube

The Washington State Department of Transportation has a YouTube channel dedicated to the big construction project that has dominated the Seattle Waterfront for the past couple of years. Here you’ll find animated videos of how Bertha the world’s largest tunnel boring machine works, loving goodbyes to the old viaduct which the new tunnel will replace, and milestones throughout the project. Above is a video showing Mario driving a go-cart through a simulation WSDOT originally posted of a temporary route for SR 99.

As we’re learning about what’s really blocking Bertha the Tunnel Boring Machine, you may want to get caught up on what Bertha is doing underneath Pioneer Square and why she’s digging a 2-mile tunnel underneath Downtown Seattle. Visit Milepost 31, the information center dedicated to the area’s history and the technology used in the tunnel boring machine. It’s located in Pioneer Square and tours of the nearby launch site are held regularly, as well as a Speaker Series on First Thursdays. There’s also a fabulous historical website called ViaductHistory.com through which visitors can explore the history of the SR 99 viaduct and surrounding neighborhoods. You can even follow Bertha on Twitter!