6 month delay ‘optimistic’ for Seattle tunnel

SEATTLE — A machine digging a highway tunnel underneath Seattle that has sat idle since December likely won’t begin working again for another six months, an official with the contractor said Friday.

But Seattle Tunnel Partners project manager Chris Dixon said that estimate is “slightly optimistic.”

The machine, dubbed Bertha, stopped working about 1,000 feet into the 1.7-mile Highway 99 tunnel. If the six month estimate holds, that means Bertha will be stopped for nine months.

“This isn’t the time to accelerate things or take short cuts,” Dixon told reporters Friday.

Dixon said the Japanese company that built Bertha will finalize a report on its options to access Bertha in about 10 days. Those options have been narrowed to three shafts of different sizes that will allow crews to reach the machine. Depending on the size of the shaft, crews will be able to take apart sections of Bertha and work on them either at the bottom of the shaft or at the street surface. Those are the details the team from Hitachi-Zosen will be exploring.

Building and designing a shaft to access Bertha will take about two months and then repairs would have to take place, Dixon added. The shaft will be about 120 feet deep and be located just south of Main Street.

The seals surround the main bearing are broken and have to repaired or replaced.

The completed tunnel will allow the state to tear down the Alaskan Way Viaduct, the 60-year-old double-decker highway along the Seattle waterfront that is in danger of collapsing in an earthquake.

The viaduct will be closed this weekend for a routine inspection. Monitors have already found the viaduct settled nearly half an inch near the tunnel-boring machine. The Transportation Department said that was expected and the viaduct is safe, for now.

Dixon added that the state got lucky the machine got struck where it did because if it would have stopped farther along, building a shaft would not have been a possibility.

He added that the scope of the problem is not fully known yet, and thus the costs of repairs has not been estimated.

More in Local News

Inclusion super important to Monroe High senior

Sarah Reeves worked to make homecoming more representative of the student population.

Man, 60, in critical condition after Bothell crash

Police believe the driver may have been speeding when he hit a rock wall.

FBI operation arrests 3 linked to exploitation of 32 women

The sting focused on Everett and other cities in Snohomish, King, Pierce, Skagit and Spokane counties.

Man arrested in Monroe Walmart robbery; second suspect flees

The pair fled in a stolen Mitsubishi Lancer with a distinctive green spray paint job.

Fugitive convict, missing more than a year, surrenders

Charles Coggins, 60, turned himself in Monday. He could now spend up to 30 days behind bars.

Former homeless camp needs needles and garbage cleaned up

The Hand Up Project will lead a volunteer effort this weekend on wooded land south of Everett.

County Council postpones vote on conservation programs

A decision on funding agricultural and water-quality programs will come after the budget process.

A Q&A with the candidates running for Snohomish County Council

Republican incumbent Sam Low faces Democratic challenger Kristin Kelly in District 5.

Front Porch

EVENTS Seahawks event postponed A Toys for Tots Blue Friday fundraiser that… Continue reading

Most Read