Program Spotlight

Launch pit complete, ready for Bertha

Tue, 14 May 2013 22:24:00 GMT

Last spring, a field of unturned dirt marked the spot where Bertha will begin digging the two-mile State Route 99 tunnel beneath downtown Seattle. One year and 86,000 cubic yards of soil later, it’s a pit fit for the world’s largest tunneling machine.

Crews finished building Bertha’s 80-foot-deep launch pit on Sunday after nearly a year spent building its underground walls, removing soil and building the infrastructure needed to support the nearly 7,000-ton machine. Its completion clears the way for tunneling to start this summer, once Bertha’s 41 pieces have been reassembled and tested at the bottom of the pit.

“If Bertha is the star of the project, the launch pit is her stage,” said Linea Laird, Washington State Department of Transportation administrator for the Alaskan Way Viaduct Replacement Program. “Completing the launch pit means we’re that much closer to the start of tunneling.”

Launch-pit construction started last summer in the work zone west of Seattle’s stadiums. Before excavation began, crews drilled more than 200 piles as many as 100 feet into the ground to form the pit’s walls. The perimeter of the pit is 80 feet wide and 400 feet long.

Assembly of the machine started at the south end of the pit shortly after it arrived last month from Osaka, Japan. Now that the front end of the pit is complete, crews have started building the body of the machine near the spot where it will first push into Seattle’s soil.

Our launch pit fact sheet has more information about the pit. Learn more about the machine at our Follow Bertha page, and be sure to follow @BerthaDigsSR99 on Twitter.

Bertha's trailing gear first into the pit

Wed, 01 May 2013 18:18:00 GMT

Last week, crews used a massive red crane to begin lowering the first large pieces of Bertha, the SR 99 tunneling machine, into the 80-foot-deep pit (pdf 485 kb) where she’ll start tunneling this summer. First up: the trailing gear, which will serve as Bertha's support system during tunneling by providing her with all of the equipment and materials she'll need to tunnel beneath downtown. The trailing gear accounts for much of the 326-foot-long machine's total length.

Crews started by lowering the 50-foot-tall, 400-ton section of trailing gear that houses Bertha's electrical systems. That piece was followed by a 750-ton section that includes storage tanks for soil conditioners, grout and other liquids needed during tunneling. It's also equipped with gear to bring in the curved concrete segments that will form the tunnel walls. A third piece of trailing gear will be lowered into the pit in the coming days.

Reassembling Bertha’s 41 pieces and testing the completed machine will take two to three months. Crews from Hitachi Zosen, Bertha’s manufacturer, are assisting throughout the process. Bertha won’t officially become the property of Seattle Tunnel Partners, WSDOT’s contractor, until she’s successfully tunneled approximately 1,000 feet beneath Seattle.

Our construction cameras offer frequently updated photos of the action, and you can get regular updates from Bertha herself by following @BerthaDigsSR99 on Twitter. A full photo gallery of the machine is available on Flickr.

Into the pit: assembly of Bertha set to begin

Tue, 23 Apr 2013 23:37:00 GMT

This week, crews will use a massive red crane to lower the first piece of Bertha, the SR 99 tunneling machine, into the 80-foot-deep pit (pdf 485 kb) where she’ll start tunneling this summer. Reassembling Bertha’s 41 pieces and testing the completed machine will take two to three months.

Crews from Hitachi Zosen, Bertha’s manufacturer, will assist throughout the process. Bertha won’t officially become the property of Seattle Tunnel Partners, WSDOT’s contractor, until she’s successfully tunneled approximately 1,000 feet beneath Seattle.

Our construction cameras offer frequently updated photos of the action, and you can get regular updates from Bertha herself by following @BerthaDigsSR99 on Twitter.

Bertha arrived in Seattle on April 2

Wed, 03 Apr 2013 01:00:00 GMT

Sixty years ago this week, Seattleites welcomed the State Route 99 Alaskan Way Viaduct to the city’s downtown waterfront. On Tuesday, April 2, the waterfront again welcomed a hulking guest: Bertha, the five-story-tall tunneling machine that will clear the way to the viaduct’s removal in 2016.

The ship carrying the machine that will dig the SR 99 tunnel beneath downtown Seattle entered Elliott Bay on Tuesday, April 2, after a two-week journey from the manufacturing plant in Osaka, Japan. The arrival of the $80 million machine will allow crews to begin offloading it in preparation for tunneling this summer.

Built in Osaka by Japanese firm Hitachi Zosen Corporation, Bertha is owned by Seattle Tunnel Partners (STP), the Washington State Department of Transportation’s contractor for the tunnel project. She was taken apart into 41 pieces, the largest weighing about 900 tons, before being loaded on the Jumbo Fairpartner in March. The Fairpartner started its 5,000 mile journey from Osaka to Seattle on March 19.

A map of locations where the public can view the machine is available on our Bertha page. We will also have a live webcam pointed at the Port of Seattle’s Terminal 46, once Bertha's ship has berthed, so you can watch the next chapter in her story unfold from anywhere. Frequent updates will continue to come via a Twitter account we launched on Bertha’s behalf in December.

Get ready, Seattle – Bertha’s on her way

Tue, 19 Mar 2013 17:32:00 GMT

The journey started today with a single ship. It will end about two weeks and 5,000 miles later in the waters of Elliott Bay, with the much-anticipated arrival of Bertha, the massive machine that will dig the SR 99 tunnel beneath downtown Seattle.

The five-story-tall machine left Osaka, Japan today aboard the Jumbo Fairpartner, the 475-foot-long vessel that will carry it across the Pacific Ocean. If the weather cooperates, the $80 million machine – which is owned by Seattle Tunnel Partners (STP), our contractor for the tunnel project – will arrive at the Port of Seattle’s Terminal 46 around April 1.

Built in Osaka by Japanese firm Hitachi Zosen Corporation, Bertha was taken apart into 41 separate pieces, the largest weighing about 900 tons, before being loaded on the Jumbo Fairpartner. Because weather affects sailing times across the Pacific, we won’t know for sure when the ship will arrive in Seattle until about 24 hours ahead of time.

The best way to track Bertha’s journey is to follow her on Twitter, where she’ll be sending out regular updates from the high seas. When she arrives in Elliott Bay, we’ll have you covered. Our Bertha page will give you everything you need to go Bertha watching, from a live webcam pointed at her arrival point to a map of locations where you can get a look at her in person. Don’t forget we have a 10-foot-long interactive model of the machine on display at Milepost 31, our project information center in Pioneer Square, in addition to photos of the machine and construction in Seattle.

After Bertha’s ship arrives at Terminal 46, crews will offload her pieces and transport them to storage areas throughout the work zone. The stored pieces will be lowered into Bertha’s launch pit for reassembly after the pit is finished in late April. Reassembly and testing of the machine will take about two months.

As Bertha’s owner, STP is responsible for ensuring she functions properly at all times. Accordingly, she went through a succession of rigorous tests in Japan, one of which revealed a problem with the machine’s main drive unit that has since been repaired. Bertha passed all of her tests and will officially become the property of STP once she’s tunneled approximately 1,000 feet without any issues.

With so much work ahead of her, we’re hoping Bertha takes some time to relax and enjoy her cruise across the Pacific. And we hope you’ll join us in welcoming her to Seattle.

The unusual (but successful) path to replacing the viaduct’s southern mile

Fri, 22 Feb 2013 21:41:00 GMT

At first glance, the curvy temporary stretch of State Route 99 that opened last fall to the west of Seattle’s stadiums seems like an unusual path for a highway to take. Certainly it’s not the straightest line between two points. But viewed in a broader context – keeping the highway open during SR 99 tunnel construction – it’s most certainly the right path. It saves everyone in the long run by maintaining a vital route to and through downtown Seattle as we continue replacing the Alaskan Way Viaduct.

Fittingly, the path to completion of that circuitous section of highway, and the permanent section immediately to its south, was unconventional. Yes, we always weigh risks and look for opportunities to save time and money. But this time our vigilance resulted in big changes – most notably swapping an underpass for an overpass at the eleventh hour – made with an eye toward big savings. The history behind that decision is a complicated one. The result is not: We replaced the southern mile of the Alaskan Way Viaduct one year early and under budget. And our last-minute design changes saved more than $50 million.

Of course, making big changes complicated an already challenging project. We knew that we would have to make minor adjustments along the way, and even re-do work in some cases. But the cost of those minor re-dos was well worth it given the overall cost savings and the safety benefit of removing half of the seismically vulnerable viaduct. Here’s the brief history of how it all went down:

- The contract to build the viaduct’s south-end replacement went to bid in early 2010.
- Our original construction budget for this project was $152.6 million, plus an additional $38 million to manage construction, and minimize risk and impacts to the public. Altogether, the total budget for the project was $190 million.
- An important component of the contract was an underpass that would allow drivers to bypass a busy train track that crosses South Atlantic Street, near the entrance to the Port of Seattle’s busiest freight terminal.
- As contractors prepared bids, a value engineering study of the program yielded the potential for major savings if we changed from the underpass to an overpass.
-Recognizing the value, and being confident in our ability to deliver the project while minimizing impacts to the public, we chose to make the switch. We removed the underpass from the contract and told bidders the overpass would be put out to bid later in a separate contract. We remained in close contact with interested bidders to ensure they understood the changes as they prepared their bids.
-Skanska USA Civil was announced as the low-bidder on the main south-end project in May 2010. Thanks to a highly competitive bidding climate, their bid of $114.6 million was 25 percent under our construction estimate. As a result of the low bid, the overall project budget was adjusted from $190 million to $152 million.

-Skanska completed their work in September 2012, one year early, at a final construction cost of $121 million. A portion of the additional cost was due to changes that were made necessary by the switch to an overcrossing. Add in the risk and construction management costs and you end up with $150 million – $2 million less than our adjusted budget.
- In May 2012, the overcrossing contract was awarded to Atkinson Construction for $29.4 million, $6.2 million under our estimate. The estimated cost for building the underpass was $90 million.
- All contracts associated with the viaduct’s south-end replacement are scheduled to be completed by the end of 2013, as originally planned.

What all of this really adds up to is this: our job is to deliver transportation projects safely, on time and on budget, while minimizing impacts to the public. With the viaduct’s south-end replacement, we did that and more. It just so happened the best way there was the road less traveled.

SR 99 tunneling machine problem nearly fixed

Mon, 11 Feb 2013 18:00:00 GMT

Last month we reported that Bertha, the machine that will dig the SR 99 tunnel, was in the midst of an extensive testing program at the manufacturing plant in Japan. During testing crews discovered a problem with Bertha’s main-drive unit, which rotates the cutterhead at the front of the machine. She has since been partially disassembled so engineers could take a closer look at the issue.

The diagnosis? Bertha’s going to be just fine.

In fact, further examination of her main-drive unit confirmed what Hitachi Zosen, the tunnel boring machine supplier, suspected when they first discovered the problem: a tolerance issue in the main-drive unit that occurred during assembly. Their quick diagnosis is helping to expedite the fix because they were able to order the parts they needed while the machine was being taken apart. Crews are now repairing the damage so Bertha can be reassembled, retested and shipped to Seattle this spring.

Seattle Tunnel Partners (STP), our tunnel contractor, expects Bertha to arrive in Seattle in late-March, a few weeks later than originally planned. This type of minor schedule adjustment is an expected part of a project this large, and will not impact STP’s overall project completion schedule. We still expect tunneling to begin this summer, and the tunnel to open in late 2015.

See you soon, Bertha.

Testing of the SR 99 tunneling machine continues in Japan

Thu, 24 Jan 2013 01:25:00 GMT

Before a professional athlete joins a new team, he has to pass a physical.

Same goes for Bertha, the world’s largest-diameter tunneling machine. She doesn’t play a sport, of course, but digging a two-mile-long tunnel beneath downtown Seattle requires just the right combination of speed, skill and body control – all hallmarks of a world-class athlete. Which is why Bertha’s manufacturer, Japanese firm Hitachi Zosen Corporation, is putting her through the wringer as they begin the long process of transferring ownership to Seattle Tunnel Partners (STP), the contracting team that will build the tunnel.

“The SR 99 Tunnel Project belongs to the people of Washington, but the tunnel boring machine will belong to us,” said STP Project Manager Chris Dixon. “It’s our responsibility to make sure everything is working properly before we start tunneling.”

That’s just what Hitachi and STP have been doing since December, when assembly of the five-story-tall machine was completed. Bertha has undergone extensive testing in recent weeks, with testing now about 60 percent finished. She was performing well until last week, when crews discovered that something wasn’t quite right with her main drive unit, which rotates the cutterhead. It appears there was insufficient clearance between a rotating and stationary portion of the main drive unit, which resulted in damage to some of its components.

While STP believes they understand the problem and have a solution, they need to partially disassemble the machine to get a better look (it was designed and built to be taken apart for shipment). Engineers will have a fuller understanding of how to fix the problem sometime next week, after they’ve examined it further.

It’s not unusual to discover issues during factory testing, Dixon said. In fact, engineers expect it. STP is working closely with Hitachi Zosen to make sure there is a sound solution to the problem before the machine leaves the manufacturing facility in Japan.

Once engineers give the okay, Bertha will be disassembled into 41 pieces and loaded on a ship to Seattle. She’ll arrive at the port terminal to the west of Seattle’s stadiums in early spring. Crews will then reassemble and fully test her again in the pit where she’s scheduled to begin her journey beneath downtown this summer. She won’t officially become the STP’s property until she’s tunneled approximately 1,000 feet without any issues.

“Our contract with STP is structured to minimize risk on taxpayers,” said Linea Laird, WSDOT’s administrator for the Alaskan Way Viaduct Replacement Program. “More than 90 percent of STP’s work will be performed for a fixed price.”

As in any large construction project, it’s likely that some individual work items will be delivered early, while others will fall behind schedule. Bottom line: this contract has only one major milestone – tunnel opening in late 2015. That’s the sort of single-minded goal that leads to success for world-class athletes, and, we hope, world-record tunneling machines.

So get on with the rest of that physical, Bertha. The team needs you.

Bertha needs a lot of help to build the SR 99 tunnel

Mon, 10 Dec 2012 19:49:00 GMT

When Bertha arrives in Seattle in spring 2013, she’ll bring with her plenty of excitement. But the project she’s a part of has already brought something very important to Washington: jobs.

Construction to replace the Alaskan Way Viaduct is boosting the local and regional economies. Seattle Tunnel Partners (STP), our contractor for the tunnel project, is a joint venture between Dragados USA and Tutor Perini Corp. STP’s team includes several local firms, among them Frank Coluccio Construction and HNTB Corp. Eighty-five percent of STP’s sub-contracts – including contractors, consultants and suppliers – are with firms located in Washington. Local labor figures prominently into our efforts as well, with the viaduct replacement program sustaining more than 3,900 jobs at the height of construction.

Still, we get a lot of questions about why Bertha was built in Japan, rather than America. The answer is pretty straightforward: her size and complexity. At 57.5 feet in diameter and more than 300 feet long, Bertha is roughly the same size as some of Washington State Ferries' largest vessels. And while the world has seen its share of tunnel boring machines, it has never seen one this big. Only a handful of facilities in the world are capable of such an undertaking. One of them is Hitachi Zosen Corp. in Japan, the firm that was selected for the job.

So while Bertha was built abroad, the SR 99 Tunnel Project is local. You can see it for yourself: our crews hard at work to the west of Seattle’s stadiums, building the massive pit where Bertha will begin her historic journey next summer – with a little help from her friends, of course.