Millennium Tower Leaned 29 Inches. Did the Bedrock Fix Work?

San Francisco's Millennium Tower leaned 29 inches by mid-2023. Engineers drove 18 piles to bedrock to stop it, but the tower gained back only about an inch. The tower opened in 2009 on friction piles socketed in dense sand 60 to 90 feet down, not anchored to bedrock like most downtown high-rises. Settlement began during construction and accelerated past projections, triggering lawsuits blaming either the foundation design or dewatering at the adjacent Transbay Transit Center. By 2021, engineer Ron Hamburger began drilling new piles to bedrock along the north and west sides, but the work itself added roughly seven inches of tilt when open boreholes let soil shift. The smaller redesign using 18 piles finished in 2023 and stopped settlement on those edges, winning a national engineering award. The forecast called for up to four inches of recovery as the opposite side settled to match; nine months later the building had straightened by about one inch, and some engineers warned the center was sinking faster than the edges.