Residents of San Francisco's leaning luxury condo tower have come up with a $100 million solution to be put in place as soon as this winter. Homeowners at the 58-story Millennium Tower, which has sunk 18 inches and tilted 14 inches since its construction, plan to submit a permit application Tuesday to drill 52 new steel and concrete piles securing the 10-foot-thick concrete mat foundation into bedrock 250 feet below, reports the San Francisco Chronicle. The 140,000-pound piles installed on the north and west sides of the tower would reverse its 14-inch tilt to the west by relieving stress on the soft soil compressing beneath, designer and engineer Ronald Hamburger of Simpson Gumpertz & Heger tells the Chronicle, which notes the work should take 18 months without much disturbance to residents.
The 419-unit tower currently has 950 reinforced concrete piles driven up to 90 feet deep, along with cracks in the foundation and windows, per Business Insider. "While the city and other experts have always certified the building as safe, this solution will eliminate any lingering questions about its stability," the president of the Millennium Tower Association's Center Board of Directors tells the Chronicle. A rep for developer Millennium Partners, which faces multiple lawsuits, adds the retrofit would make the tower "one of the safest buildings in California." Original developer Mission Street Development has agreed to perform the work, with the funds coming out of an eventual settlement. Work could begin in late winter or early spring, if approved by a panel of experts. (Pisa's Leaning Tower has lost some of its tilt.)