Bertha is drilling the last 100 feet of the SR 99 tunnel

Bertha’s journey has almost come to a close: The tunnel boring machine finished the weekend with fewer than 100 feet left to drill.

A project Twitter update posted Sunday morning announced that the path left to drill is down to double-digit numbers after making progress all weekend.

As of Friday, the machine was 127 feet from the finish line. At this rate, it shouldn’t be too long before the drill’s fraught journey comes to an end.

Once Bertha reaches the end of the route, the drill with pause briefly before drilling through a wall to reach a disassembly pit near Seattle Center. From there, the cutterhead will be dismantled into 20-ton chunks before being removed from the pit.

The emergence, nearly four years in the making, will be livestreamed. WDOT will post a link on the project’s website when video is available.

Barring any major delays, Bertha would seem on track to come out ahead of a previous estimate that placed the finish date as sometime in May. The project’s most recent update says the date of the breakthrough is still to be determined.

The whole project was initially estimated to be completed by December 2015. Project delays have included a two-year halt for repairs from December 2013 through December 2015.

WSDOT estimates the tunnel should be ready for traffic in 2019.

• @BerthaDigsSR99 on Twitter [WSDOT]
• Bertha is 127 feet from the finish line [WSDOT]
• See inside Bertha the tunnel boring machine [CS]
• Bertha could reach wall at end of tunneling route this week [CS]