Tag Archives: sinkhole

Sound Transit can’t avoid the voids

The Seattle Post Globe fills us in on the filling of an eighth “void” along the tunnel excavation route at 18th and Lander. Another potential void is also being examined at 17th as well. Crews are expected to complete investigation and repairs by May 22nd.

After the initial report of the sinkhole that rose all the way to the surface, subsequent voids were identified by reviewing records of excavation spoils for abnormally high readings originally attributed to mismeasurement, accuracy, or instrument calibration issues.

BHB reader Heidi wrote this morning about having seen crews working at these repair sites (and being a bit hesitant about answering questions) and pointed out the crumbling retaining wall nearby. Interestingly, in the Post Globe report Sound Transit spokesman Bruce Gray states no structural damage has been reported from these voids and that only a quarter-inch of settling has been measured, and none of that near the void sites.

Thanks Heidi!

Underground voids found, filled by Sound Transit

In addition to the one that came all the way to the surface, the Seattle Post Globe reports Sound Transit has found an additional six underground voids above the bored tunnel on the East side of the hill. Six of the seven total found voids have now been filled with concrete at a cost so far of about $1 million. Keep an eye out for more shifting soil!

Update: KOMO reporter (and Beacon Hill resident) Travis Mayfield has a video report on this story.

Sinkhole develops over light rail tunnel

The P-I reports on a sinkhole that appeared at 18th and Lander above the northbound light rail tunnel. Numerous trucks delivered fill material today to solidify the 18-inch hole that widened as it descended. Sound Transit is monitoring the area for any further problems.

(Edited: An earlier version of this post said that the sinkhole developed “due to Sound Transit construction.” The cause of the sinkhole has not been determined.)