That Sinking Feeling
Reaching the bottom of the tunnel boring machine's access pit certainly seemed like good news. Bertha has been stuck between Jackson and Main Streets—just 1,000 feet into its two-mile journey—since December of 2013. Washington State Department of Transportation administrators looked peppy and refreshed on February 9 when they shared news with the Seattle City Council that their contractor had poured 1,000 cubic yards of concrete into a cradle that would hold the broken parts of Bertha as workers got the machine out.
But "peppy and refreshed" can't be how they really feel. The project continues to be plagued by uncertainty and mishaps. WSDOT still has not specified when Bertha might be able to start drilling again. The process of getting the machine out from behind a 20-foot concrete wall is pretty complicated. If Bertha can't bore its way through the pit's wall, the contractor will have to go in from the other side, and workers will have to slide parts of the machine down specially lubricated rails. Then they'll have to hoist those machine parts out with a giant crane, repair a broken main bearing and seal array, reattach those parts, and then fill the pit back up with soil.
And, as you've probably heard, on February 12, an incident occurred nowhere near the pit: Four workers were injured on a completely separate part of the tunneling project, when an elevator wall collapsed near the tunnel's planned north portal.
And don't forget the series of small heart attacks city and state officials had over settlement in Pioneer Square last fall. Bertha is not just drilling underground, she's also drilling in a place that used to be underwater, and the dewatering of the rescue pit, a probable cause of the settlement, will continue while Bertha gets repaired. While WSDOT has reported stability overall in nearby soil since last fall, both WSDOT and Seattle Public Utilities noted at that same city council meeting that there was one point that's shown slow settlement since December. That point is right where Yesler Way meets Western Avenue.
This intersection is less than 200 feet from the Alaskan Way Viaduct. It's a spot where the ground is already funky: Parts of the sidewalk on Yesler already look like old people's lips after their dentures have been removed. Sidewalk slabs angle downward from the bases of buildings, revealing cracks along the edges.
How much the Western/Yesler intersection has settled is still up for debate. WSDOT told the city council that there's a discrepancy between the two agencies' measurements. Both agree that at least a tenth of an inch has sunk, while WSDOT's contractor continues to extract water from the tunneling machine's rescue pit. But there seems to be some wiggle room for that figure. "We're working with them to try to resolve the differences," SPU spokesperson Andy Ryan told me over the phone.
None of this bodes well for a 100-year-old, 20-inch cast-iron water main running north to south beneath the intersection. According to a memorandum of agreement with the state that the city passed in 2011, the maximum uniform settlement allowed for that pipe is 0.92 inches. According to SPU's measurements, it's already sunk 1.16 inches since construction began—meaning that the level of settlement violates the earlier ordinance.
But what does all this mean for the viaduct? WSDOT announced on February 13 that a section of the viaduct south of Main Street had sunk another quarter inch, though it maintains that the viaduct is stable. Meanwhile, the Seattle Department of Transportation has hired its own consultants to review WSDOT's work and measure viaduct safety. The next time we'll hear something from those consultants, according to SDOT, is in the form of a Seattle City Council briefing next month, in early March.
Early March feels far away, and the public doesn't have direct access to WSDOT's, SDOT's, or SPU's data—other than what the agencies choose to share. Historically, the state hasn't exactly been eager to share its data, even with city leaders. (And yet, after a state-city tiff over startling wording in a tunneling engineer's report revealed in January, that's supposed to change.)
So that's how I found myself—me, myself—lying down on the sidewalk next to Seattle Public Utilities' GPS monitoring station. I was trying to do my own informal survey of settlement, using nothing but my own body and the iHandy Level app on my iPhone. Maybe my chakras would feel particularly unaligned, I thought, and that would tell me something, since WSDOT, SDOT, and SPU aren't telling me much.
I placed my backpack on the sidewalk next to the monitoring station on the northwest corner of the Western/Yesler intersection and assumed the lotus position. People said nothing as they politely navigated their bikes and children past my body. I changed positions and lay down. After about 10 minutes, I can't say I detected any movement. The app didn't, either.
For the record, I had made SPU aware of my plan before I went out. Andy Ryan, the SPU spokesperson, paused when I told him and said, "That oughta work."
It didn't. Guess we'll have to wait for the official assessment.