Planned Fix for Sinking Tower Hits Big Snag

San Francisco has been struggling for years with its Millennium Tower, an architectural fiasco that has seen the building slowly leaning and sinking into the ground below it. Now, the expensive plan to fix it may be in jeopardy, with reports that an underground shoring wall is now a wrench in the works. The original $100 million scheme to remedy the sinking situation involved driving 52 piles 250 feet into the bedrock on the northwest corner of the structure, where the tilting is occurring, to slowly shift the weight and push the building back into position, per SFGate.

Now, the 90-foot, 3-foot-thick wall made of steel and cement on the eastern side of the building is a sore point, as it could slow or stop the building from completing its reverse-tilt to the east. Three years ago, the building's chief engineer, Ronald Hamburger, had offered assurances that the wall wasn't going to be a problem in terms of reversing the tilt—which NBC Bay Area now puts at 28 inches—explaining the wall would eventually itself sink into the surrounding clay. In an email to SFGate, he continues to insist that the fix will still be attainable, noting they've known about the wall for eight years and that their plans will enable the tower to even out in "small amounts" over the next four decades.

Hamburger also disputes that the tilt is currently at 28 inches, claiming a 25 1/2-inch tilt to the west and a much smaller lean to the north of 8 1/2 inches. A local geotechnical engineer shakes his head at Hamburger's remarks, however, calling him "almost certainly" wrong, per SFGate. "He was, as usual, guilty of wishful thinking rather than carefully looking into the details," the engineer notes of Hamburger's explainer back in 2019. Meanwhile, the fix for the 58-story tower, built in 2009, was revised earlier this year, and just 18 piles were installed in mid-March, per Ground Engineering. However, digging caused further sinking, and construction was halted. One expert tells NBC the wall may have been the cause of the tilting in the first place, and now "could be a big barrier to ... getting this project" upright. (More Millennium Tower stories.)