(WSDOT photo)

If the Highway 99 tunneling machine keeps digging at the same pace of the past few days – 61 feet between yesterday’s update and today’s update, and 127 feet to go – next week could bring the breakthrough. Just a reminder that WSDOT and Seattle Tunnel Partners are NOT opening the site for the public to watch it happen, but they’re working on some kind of a live feed. Once the machine gets to the end of the line, it will be broken into pieces, which is why they’re calling what you see above “the disassembly pit.”

We’ve been watching the Highway 99 tunneling-machine update page, now that “Bertha” is getting close to breakthrough, and just noticed that today’s update says 219 feet to go – same as yesterday. WSDOT explains via Twitter that “(Seattle Tunnel Partners) is wrapping up routine maintenance and plans to resume mining tomorrow.” So for those who speculated breakthrough might happen this week – highly unlikely.

(WSDOT photo of ‘disassembly pit’ that accompanied today’s progress-report tweet)

The Highway 99 tunneling team has now moved from twice-weekly progress reports to daily progress reports. Not that the tunneling machine is on an “any day now” basis yet, but here’s what WSDOT reports this afternoon:

Seattle Tunnel Partners is making final preparations for the SR 99 tunneling machine’s arrival at the disassembly pit near Seattle Center. Because mining rates will continue to vary as crews approach the pit, we can’t predict when Bertha’s breakthrough will occur. We will continue to provide regular progress updates along the way.

We recognize that there is great interest surrounding this stage of the project, and we are working on ways to share this historic moment with the public. We will be activating a new time-lapse camera as well as streaming video of the disassembly pit prior to breakthrough. These cameras will offer the best view of Bertha’s arrival in the pit. We will also continue to share photos and provide frequent updates via social media, including daily progress updates. For safety reasons, the public will not be allowed in the construction zone during the breakthrough.

Look for more updates soon about the breakthrough sequence, the process for disassembling Bertha and the work that remains before the tunnel opens in 2019.

As of today, WSDOT tweeted, “Today Bertha has 320 feet to go – less than the Mariners 326′ right-field foul line in Safeco Field.” They’ve said that they won’t be setting up an in-person breakthrough-watching event because the pit is in the middle of a construction zone.

(WSDOT photo: Crews assembling rebar for a section of the foundation to support northbound SR 99 roadway and wall on west side of roadway)

The Highway 99 tunneling machine is back on the move, and re-aligned after veering a half-foot off course, according to this update late today from WSDOT:

Seattle Tunnel Partners resumed mining today after conducting additional survey work to verify Bertha’s position and to make necessary adjustments to complete the tunnel drive. Crews performed routine inspections and maintenance while mining was stopped, including the replacement of cutterhead tools.

As of this afternoon, Bertha was tunneling north toward the intersection of Denny Way and Sixth Avenue North, less than 1,000 feet from the disassembly pit.

STP stopped mining on February 28 after survey data indicated the tunneling machine may be several inches off the tunnel alignment. Three independent surveys confirmed the 57.5-foot machine was approximately six inches off alignment.

STP designers made a slight change to the tunnel alignment between the machine’s current location and the end of the tunnel drive. Adjustments are common during tunneling, including on this project. STP made a similar adjustment to correct Bertha’s course after the machine mined out of the access pit following repairs.

Crews steer Bertha based on information they receive from its on-board guidance system. The system is now set to the new tunnel alignment. According to STP’s most recent schedule, Bertha will arrive at the disassembly pit in May.

(WSDOT photo taken last month – work crews in the tunnel)

WSDOT says tonight that the Highway 99 tunneling machine is expected to arrive in its “disassembly pit” in May. That news comes as they also announce that Seattle Tunnel Partners has stopped digging to get the machine ready for the “final 1,000 feet of the 9,270-foot tunnel drive.” They’re checking its position because, WSDOT’s update says:

Recent surveys show that Bertha may be several inches off of the tunnel alignment. STP is conducting additional survey work and will make adjustments as needed to complete the tunnel drive.

Adjustments are common during tunneling, including on this project. STP made a similar adjustment to correct Bertha’s course after crews mined out of the pit that was used to access and repair the machine.

Crews will continue to perform routine maintenance on the machine for the next several days. They plan to resume mining next week.

According to STP’s most recent schedule, Bertha will arrive at the disassembly pit in May. The pit is located approximately 960 feet north of the cutterhead’s current location beneath Denny Way and Sixth Avenue North. Mining rates will continue to vary based on maintenance needs and soil conditions.

Crews successfully mined under the final building of the tunnel drive earlier this week. Bertha has traveled a total of 8,310 feet and built 1,270 of 1,426 concrete tunnel rings.

Because the end-of-the-line pit is part of a construction site, WSDOT has said it’s not planning to have a big event for the public to watch the machine break through.

Meantime, yet another reminder – the Alaskan Way Viaduct is scheduled to close for inspection 6 am-6 pm each day this Saturday and Sunday, with a few other events on 99 north of the Battery Street Tunnel – full details are here.

(Tunnel as seen from machine – WSDOT photo taken earlier this month)

Since the last twice-weekly update, the Highway 99 tunneling machine has passed the 8,000-foot mark of its 9,270-foot route. To be specific, as of today, it’s dug 8,132 feet and has 1,138 feet to go – about two more blocks, according to today’s WSDOT update. It’s currently near 6th/Wall and set to emerge at 6th/Thomas.

P.S. If you missed it earlier today, WSDOT has announced the Alaskan Way Viaduct’s next weekend maintenance (etc.) closure will be March 4-5.

Last weekend, we noted that the Highway 99 tunneling machine was in the zone where it would pass beneath the Battery Street Tunnel and the Seattle Center Monorail. This afternoon, WSDOT reported that it’s gone beneath the former and on its way to the latter. The machine is now 115 feet beneath the surface and climbing upward, 100 feet higher than the tunnel’s deepest point. WSDOT also reports that roadbuilding continues and is already halfway down the 7,692-foot path that’s been dug – here’s a document with updates on that and other parts of the project. WSDOT adds, “Work has also begun on the mechanical, electrical and plumbing systems within the tunnel. Crews began installing these systems near the stadiums last week …” Read today’s full tunneling update here.

Somebody asked us how the Highway 99 tunneling machine is doing. While WSDOT hasn’t had many major updates lately, it’s continuing the routine of publishing distance updates on this page on Mondays and Thursdays, and according to the newest number – 7,499 feet dug, of the 9,270-foot route – it’s now more than 80 percent of the way to the end. The zone it’s in now goes below the Battery Street Tunnel, which will be decommissioned when the new tunnel opens, and beneath the foundation of the Seattle Center-to-downtown Monorail.

WSDOT just published that new video about working hyperbarically with the Highway 99 tunneling machine as it continues a maintenance stop before moving on to dig the final 25 percent of its 9,270-foot path – explaining, among other machines, that the machine is underwater as well as underground and is therefore something of “a submarine.” During the maintenance work that’s been under way since January 5th, crews have replaced 250 cutterhead tools, like these:

See the latest tunnel update here; the machine’s current location is shown here.

(Map showing the zone where the tunneling machine is now, from WSDOT’s update page)

Among those taking time off for the holidays, the Highway 99 tunneling-machine crew. Here’s the last update of the year from WSDOT, with a bit more than one-fourth of the way to go on the tunnel route:

Seattle Tunnel Partners crews built their final concrete tunnel ring of the year on Tuesday before stopping for the holidays. The remaining days of 2016 will include a break for crews, followed by scheduled maintenance on Bertha, the SR 99 tunneling the machine.

In the year since STP restarted tunneling, Bertha has traveled approximately 5,700 feet and built almost 900 rings. Along the way, crews continued to control the ground as they mined beneath streets and structures, including the Alaskan Way Viaduct.

When mining resumes early in the new year, Bertha will be less than 2,500 feet from the pit near Seattle Center where she’ll emerge at the end of her journey. STP will continue to inspect and perform maintenance on the machine as needed.

Bertha’s cutterhead is located approximately 160 feet below Third Avenue between Blanchard and Bell streets. Progress updates are posted on Mondays and Thursdays at our Follow Bertha page. You can also follow Bertha on Twitter @BerthaDigsSR99.

Happy holidays from the Alaskan Way Viaduct Replacement Program. We’ll see you in 2017.

Current estimate is for the tunnel to open in early 2019. That’ll be almost a decade after the waterfront ceremony formalizing the plan; at that time, the hope was for a 2015 opening.

That time-lapse video shows road-building inside the under-construction Highway 99 tunnel, and it accompanies WSDOT’s latest update on tunneling progress. The tunneling machine is now more than 70 percent of the way along the 9,270-foot route, according to WSDOT, which included the video in this update published today. It’s the second update of the week – this one details progress at the tunnel’s “south portal.” It’s been almost a full year since tunneling resumed on December 22, 2015, two years and two weeks after the machine stalled.

While the Highway 99 tunneling machine hasn’t made much news lately, it’s continuing to dig steadily along, says WSDOT. Their latest twice-weekly update, published this afternoon, says it’s more than two-thirds of the way down the route – 6,337 of 9,270 feet. It’s already gone past the deepest point on the route and is starting to climb back toward the surface, currently in the zone beneath Belltown. The current estimated opening date remains early 2019, and as noted in this tweet, Viaduct demolition would follow over much of the rest of that year.

The Highway 99 tunneling machine has passed the one-mile mark as of this morning, according to WSDOT. It’s also made a new video showing how the machine is steered along its designated path underground, considering there’s no GPS:

The machine is at its deepest point – around 200 feet underground – with just under 4,000 feet remaining on the route, which is shown on this map, along with the machine’s approximate current location. The most recent timeline says that absent any further major problems, the tunnel will open in 2019.

While the Alaskan Way Viaduct is closed this weekend for its twice-yearly inspection, the machine digging its replacement will be taking a break for inspection too. WSDOT announced this afternoon that the Highway 99 tunneling machine has made its third maintenance stop of the year and will likely be stopped for about a month.

It’s currently stopped about 190 feet under First Avenue, north of Pike Street, and has now gone 4,721 feet, more than half the 9,270-foot tunnel route. You can read WSDOT’s update in full here; in short, crews will be inspecting and changing some of the machine’s 700+ cutting tools. This year’s two previous maintenance stops were March 12-April 29, just before the machine went under the Viaduct, and June 23-July 18. The newest schedule revision says the tunnel will open in early 2019.

P.S. Above ground, the Viaduct inspection closure is scheduled for 6 am-6 pm Saturday and Sunday. These often end early, and we’ll let you know if/when this one does.

(August 31st photo by Vlad Oustimovitch)

WSDOT announced this afternoon that the Highway 99 tunneling machine is back on the move after a two-week stop to change cutterhead tools. Above is a photo of a used “tooth,” taken by Vlad Oustimovitch, a West Seattle resident who is a longtime member of the citizens’ advisory group and shared photos with WSB after a tour of the machine toward the start of the stopdown. Today’s WSDOT update says that as of lunchtime, “crews were tunneling north approximately 170 feet below First Avenue, just north of Union Street” and that the contractor “replaced a total of 14 large cutting tools during the two-week maintenance period. Bertha has moved from clay to a mixture of sand and gravel that wears down cutting tools more quickly. … The tools STP changed during this maintenance stop are the first parts of the cutterhead that contact the ground, making them crucial to the machine’s ability to excavate soil. STP will continue to inspect and replace these tools as needed during the course of mining. … The machine has tunneled more than 4,135 feet and is nearing the halfway point of its 9,270-foot-long journey.”

(UPDATED 9:36 PM WITH PHOTOS FROM TOUR TODAY)

(WSDOT image)

ORIGINAL REPORT, 4:26 PM: Since its last maintenance stop ended in mid-July, the Highway 99 tunneling machine has dug 1,000 feet. Another 500, and it will be at the official halfway mark. But right now, WSDOT says, the machine is stopped down “to inspect and replace some of the larger cutterhead tools on the front end … STP chose to check the tools – and change them as needed – because Bertha has moved from clay into a mixture of sand and gravel that will more quickly wear them down. Replacing the tools now will preserve the machine and ensure it continues to function well as it mines toward STP’s next planned maintenance stop.” You can read the full update here, and you can go here to see where the machine is now – that’s also the page that tracks its progress, currently listed as 4,135 feet along the planned 9,270-foot tunneling route.

ADDED 9:36 PM: A West Seattleite who has long represented our area on Viaduct/Tunnel advisory groups, Vlad Oustimovitch, is sharing photos tonight from a tunnel-project tour earlier today. First photo shows a used drilling tooth that was replaced today, as part of the work mentioned above:

Next, you’re looking at “giant rollers” that hold up the tunnel-building part of the machine:

Here are the pistons that push the machine forward once rings are in place:

Another view from inside the tunneling machine:

Here’s the control room:

And “the tail end” of the machine:

Back outside the machine, in the already-built 4,135 feet of tunnel, here’s a look at the upper deck:

Oustimovitch was one of “about eight” people on today’s tour.

(WSDOT video from last week, showing road-building in the tunnel section dug so far)

Just announced by WSDOT – the Highway 99 tunneling machine is back in action after “a month of routine and hyperbaric maintenance” that started June 23rd and ended yesterday. WSDOT says, “The maintenance period included more than 40 shifts of work under hyperbaric conditions, changing cutting tools and performing other maintenance in the space behind the cutterhead.” The tunneling machine is one-third of the way – 3,108 feet – along the route, now “located approximately 120 feet beneath Spring Street, tunneling north toward First Avenue.” Two more stops like this are expected, WSDOT says.

(WSDOT graphic)

It’s a question still asked fairly often – when the Alaskan Way Viaduct is gone and the tunnel is open, how will you get to downtown from northbound Highway 99? WSDOT has just announced it’s chosen the builder for the ramp that answers the question:

Construction will soon begin on a new flyover off-ramp designed to connect the northbound lanes of State Route 99 to Seattle’s stadiums, Pioneer Square, and downtown Seattle.

The Washington State Department of Transportation awarded the $3.5 million contract to Interwest Construction, Inc. of Sequim to build the ramp to South Dearborn Street that will allow northbound traffic to exit in Seattle’s SODO neighborhood when the new SR 99 tunnel opens.

“The flyover ramp is an important piece of the larger Alaskan Way Viaduct Replacement Program,” said David Sowers, deputy program administrator for the Alaskan Way Viaduct Replacement Program. “And drivers should not worry about construction delays, as the ramp will be built in the existing SR 99 work zone near the stadiums.”

WSDOT and Interwest expect to sign a contract giving notice to proceed later this month. Construction activities are expected to start in July and last approximately six months. The new off-ramp will open to motorists at the same time as the new SR 99 tunnel, currently scheduled for 2018.

The latest tunneling-progress report, by the way, is here; as of last Thursday, 2,886 feet tunneled, about 200 feet shy of a third of the 9,270-foot distance.

In the middle of the second week post-Viaduct closure, an update on the Highway 99 tunneling machine: After a “break for rest and routine maintenance,” WSDOT says this afternoon, “Seattle Tunnel Partners resumed mining late Tuesday evening.” The machine has now gone more than 2,000 feet in all, which is more than 20 percent of the way along the full tunnel route, shown in the WSDOT-created graphic above. It also shows the machine in Zone 2, which will take it under the Columbia onramp; as explained during the closure, when we asked WSDOT on behalf of a reader, the machine is much further beneath that structure, so a precautionary closure was NOT considered necessary. WSDOT says that from there, the machine will travel under Western Avenue, and they promise twice-weekly updates here.

As of a few minutes ago, the northbound Alaskan Way Viaduct [“live” camera above] has reopened, following the southbound side [“live” camera below] by about half an hour.

And that concludes the almost-ten-day closure, five hours after today’s surprise announcement of an early ending to what was expected to be a shutdown lasting about two weeks. Full backstory in our afternoon report published right after the news broke.

8:18 PM: Carol points out in a comment that the ramp from the EB bridge is still blocked off – the camera verifies – so crews haven’t gotten there yet.

8:51 PM: WSDOT says the ramp is open now. (Here’s the camera view.)

9:18 PM: Thanks again to everybody who helped out by sharing commute reports this past week and a half – and remember that we have long been reporting on the morning commute every weekday, so we’ll be back at it tomorrow (just not quite as early!). And remember, another major project is ahead – overnight closures of the west end of the bridge, starting in a week, for the Fauntleroy Expressway seismic-cushion re-replacements.

9:58 PM: Just in case you missed this earlier: Metro’s plan:

All Metro routes that normally serve the Alaskan Way Viaduct will return to their regular routes and stops at the start of service Monday morning, May 9. … With the start of service on Monday, the bus stop on westbound Columbia Street at Second Avenue will reopen to regular transit service, and Viaduct buses will no longer serve the temporary stops they made in the SODO area on or near S Lander Street during last week’s closure.

All riders should note that Viaduct service will remain on the current reroutes throughout Sunday night and until about 4:30 AM on Monday.

And the Water Taxi will continue its extra West Seattle parking and extra Vashon runs for one last day, tomorrow morning. Then everything is back to normal Tuesday.

(7:01 PM UPDATE: The Viaduct is now open southbound)

ORIGINAL REPORT, 2:14 PM: Just in from WSDOT – The Alaskan Way Viaduct will be reopened in time for the Monday morning commute. The first news release:

After 10 days of around-the-clock tunneling, Bertha’s biggest hurdle is now behind her. That hurdle – the Alaskan Way Viaduct she was built to replace – will reopen for the Monday morning commute, bringing an early end to the much-anticipated #99closure.

Structural engineers with the Washington State Department of Transportation completed a thorough inspection of the viaduct on Sunday. Their inspection confirmed what a team of engineers observed throughout the past 10 days of tunneling: continued stability of the ground and the viaduct.

Contractor Seattle Tunnel Partners estimated that tunneling beneath the viaduct would take approximately two weeks. With the ground holding steady, and the most challenging part of the machine’s drive beneath the viaduct complete, WSDOT made the call to reopen both directions of State Route 99 through downtown.

“Closing a major highway is never easy, and the public deserves a big thank you for their patience and flexibility while this crucial work took place,” said Gov. Jay Inslee. “I would like to thank the WSDOT and STP project teams and construction crews on a job well done. To finish this piece of the project almost a week early is commendable. The planning and flexibility of commuters, along with strong coordination between WSDOT and partner agencies, ensured commuters had access to real-time information that helped them plan ahead.”

WSDOT temporarily closed SR 99 through Seattle so crews could more closely monitor the structure as the machine passed beneath. The tunnel team originally planned to keep the highway closed until after the machine had completely cleared the viaduct, but the success of the tunneling operation and the continued stability of the ground led to discussions of an early opening as work progressed.

By Friday, the machine had successfully tunneled through complex soils only 15 feet below the viaduct’s foundation – the closest the machine will come to any structure at any point in its drive beneath Seattle. On Sunday, STP completed installation of the rings beneath this critical location, clearing the way for the final inspection and the early opening of the highway. WSDOT’s 24-hour command center will remain open until the machine has successfully tunneled 385 feet, the distance at which it will be completely clear of the viaduct.

WSDOT worked closely with Seattle Department of Transportation, Seattle Police Department, King County Metro, King County Water Taxi, Sound Transit, Community Transit and the Port of Seattle to keep traffic moving and provide travel options for drivers during the closure.

“Removing traffic from the viaduct was critical to the success of this work, but we don’t want the closure to last a moment longer than it needs to,” said Acting Transportation Secretary Roger Millar. “I want to thank the WSDOT and STP project teams as well as our local partners for successfully managing the closure of a major highway in our system. And, a special thank you to the community for their patience. I hope commuters saw the value of having several transportation choices, and consider using alternatives to driving alone more regularly going forward.”

Millar said the success of STP’s drive beneath the viaduct will help build momentum for the remainder of the tunnel drive.

“The end of this closure marks a new beginning for the SR 99 Tunnel Project,” he said. “Much work remains, but we are encouraged by the contractor’s performance during this phase of the project. Our shared focus now, as it has been, is on delivering this tunnel to Washington taxpayers.”

ADDED 2:32 PM: The 99closure.org website has some additional practical details about how the closure will end – read the post in full here – some key points:

Water Taxi resumes regular service Tuesday morning, May 10
The King County Water Taxi will continue additional parking options at West Seattle (PDF) and additional sailings on the Vashon route (PDF) through the end of the day on Monday, May 9.
Regular West Seattle and Vashon Water Taxi service will start Tuesday morning, May 10.

Metro Transit returns to regular routing Monday, May 9
King County Metro Transit service will resume regular routing via the Alaskan Way Viaduct with the start of service Monday morning. At that time, the bus stop on Columbia Street at Second Avenue will also reopen.
Current surface street reroutes through SODO and temporary stops remain in effect for the remainder of Sunday, May 8.

Restrictions on city streets lifted for Monday morning commute
With the exception of parking restrictions along Harbor Avenue in West Seattle, temporary city street restrictions put in place for the closure will be lifted before Monday morning.

WSDOT is having a media conference call at 3 pm and we’ll be on it; updates to come.

3:15 PM: Just off that conference call. The big news – the Viaduct actually will reopen TONIGHT, per WSDOT’s Todd Trepanier. The barrier removal will start as soon as 4 pm – they’re calling in crews to get that done.

He said what makes the early reopening possible is the ground stabilization techniques that contractor Seattle Tunnel Partners has been using.

He also said that when the machine gets to the 380-or-so-foot spot, they’ll pause before going on to the next phase – they’ll continue working 24 hours a day until then.

7:01 PM: As reader Kyla reported in comments, the southbound Viaduct is now open. This camera is proof.