SR 99 tunneling machine passes 300-foot mark

Posted on Oct 16 2013 5:06 PM

We’ve said it before, but after the week Bertha just had, it’s worth saying again: Tunneling is a notoriously uneven endeavor. Some days the digging is easy. Other days you don’t move at all.

After passing the 200-foot mark in the early part of last week, Bertha spent the latter part of the week in a holding pattern so crews could perform routine maintenance. She was back at it on Monday, Oct. 14, digging 18 feet. Then came Tuesday, which saw Bertha dig 46 feet, her most productive day yet.

Total it all up and you’ll see that Bertha traveled 92 feet in seven days, an average of 13 feet per day – a respectable number that becomes more impressive when you consider the fact that she was sitting idle for three of those days.

Bertha has now dug a total of 301 feet and built 38 permanent tunnel rings. She’s completely buried underground, digging her way toward South King Street.

Check out this short video of Bertha in action, and don't forget to follow @BerthaDigsSR99 on Twitter for the latest on her journey beneath downtown.