Mesmerizing video captures giant drill completing tunnel in U-District

SEATTLE - And just like that, 200,000 tons later, Brenda gets a day off.

Brenda, of course, is a tunnel boring machine that's been at work drilling two 3.5 mile tunnels for the light-rail trains that will run between Northgate Mall and the University of Washington beginning in 2021. On Friday, Brenda completed the third segment, breaking through the wall of what will eventually be the U-District station.

Sound Transit filmed the breakthrough; suffice to say, it's mesmerizing.

“Three tunnel segments are done; three more to go to reach Husky Stadium," said King County Executive Dow Constantine.

Brenda's been at work since July 2014, and was joined by another machine dubbed Pamela last November.  Tunneling is scheduled to be completed late next year.