Sinking and Tilting Millennium Tower Engineer Says Needed Soil Expert
The Millennium Tower was discovered in August 2016 to be sinking faster and further than anticipated—over sixteen inches—and leaning over two inches. The building was exhibiting cracks down in its basement and garage areas. The rapid sinking (over a period of years) and tilting caused a firestorm of concern among homeowners in the 58-story tower who saw their condo worth fall, with condos becoming difficult to sell, and the building companies and city agencies and regulators involved in the project pointing fingers of blame at each other. The city administration has declared the building safe to live in. Multiple lawsuits have been brought.
Recently UC Berkeley Professor Jack Moehle (who originally certified the tower’s design as structurally sound) along with peer review colleague Hardip Pannu were brought in by Di Simone Consulting Engineers to go over the tower’s foundation structural soundness—as part of the city’s Department of Building Inspection program. They concluded that the builders should have brought into the team a geotechnical expert at the time of the building’s final peer review to ensure the strength of the soil supporting the building.
Moehle told the board of supervisors that the project did have geotechnical experts early on in the planning, but during the peer review process a geotechnical engineer should have been part of the peer review. As it was, Moehle signed off on the building itself, but said he was not qualified to sign off on the soil strength.