The Saga Of S.F.'s Sinking And Tilting Millennium Tower
Ever since news broke over the sinking and tilting of Millennium Tower in San Francisco, there has been a litany of news reports and lawsuits. Issues with settling and the building's foundation have created a new emphasis on the stability of the foundations of other high-rises going up downtown. Even as developers of nearby projects, including 181 Fremont, have highlighted the durability of their foundations drilled into bedrock, Millennium Tower continues to make headlines in the battle between the developers, condo owners, city and others.
To understand the issues with Millennium Tower, Bisnow took a closer look at recent events. Here's what we know so far:
When reports started coming out about how Millennium Tower had already sunk 16 inches and was tilting two inches to the northeast, residents hired engineering consultants to assess the problem and to see how bad it was. The building was only supposed to settle 12 inches during its lifetime. The condo association and developer launched initial talks to find ways to fix the situation. One engineering company estimated the tower would sink another eight to 15 inches if no measures were taken to fix the problem.
San Francisco Board of Supervisors started investigating the situation, asking city building department officials to explain why the developer was allowed to avoid anchoring the high-rise into bedrock.
Supervisor Aaron Peskin discovered documents dated February 2009 where the chief building inspector wrote to the engineering firm about unexpected settlement. The firm replied the settlement was at 8.3 inches but was still safe. The inspector believed the situation was under control.
City attorney Dennis Herrera subpoenaed the developer as part of the city’s investigation.
Meanwhile, Millennium Partners insisted the foundation was fine and up to the city’s building code. It said nearby construction at the Transbay Transit Center, which included pumping out groundwater, led to softening and compressing the soil.
The TJPA said the developer should have used end-bearing piles that would have reached to bedrock instead of resting on over 900 friction piles driven into dense mud. Millennium Partners shot back, saying the tower is not the only site to be built above dense sand. The firm said the Embarcadero Center and the San Francisco Museum of Modern Art have similar foundations.
Homeowners hired soil experts to drill six-inch holes to test water and soil conditions and to measure the tilt of the building.
Iowa State University architectural design professor Tom Leslie proposed one solution to the problem: build a larger, heavier structure to the north of the tower connected to the building’s frame to balance out and support Millennium Tower.
Simpson Gumpertz and Herger Structural engineer Ron Hamburger said in a report about the tower that, despite the lopsided settlement, the building would most likely survive a major earthquake and is safe for occupancy.
Reports on Millennium Partners’ next project at 706 Mission St. indicated the mixed-use development was not designed with piles. The building is held up by a four-story basement garage sitting upon a bowl-shaped concrete slab 12 feet thick with five-foot-thick edges.
Millennium Tower homeowners asked for a reduction in property tax, saying the problems at the tower were decreasing property values.
City attorney Herrera sued Millennium Partners and said the developer violated the law by not disclosing the building’s settlement problems. The city attorney said the developer may have known about the problems as early as a year before condos went on the market. The lawsuit was a cross-complaint filed by the homeowners association against the TJPA. The city attorney said the homeowners should have sued the developer.
City officials declared panels that review building safety must include city-hired consultants going forward. San Francisco assembled a peer review panel to look at the developer’s engineering report that said the building was safe.
The city issued a 90-day notice to fix disabled access ramps deemed too steep and said the developer did not receive proper permits to fix water damage in the basement.
Satellite imagery showed the tower is sinking and potentially at a faster rate than previously thought. Engineers previously said the tower was settling at one inch per year, but satellite imagery revealed it had sunk roughly 1.6 inches to 1.8 inches over a one-year period and about 2.6 inches to 2.9 inches over a 17-month period.
Millennium Tower’s penthouse sold for $13M, the most expensive condo sale in five years. A veteran tech executive, Craig Ramsey, bought the 5k SF penthouse despite ongoing lawsuits over the property. He said the price was reasonable and that he expected the building to be repaired and remain livable. The previous owner bought the penthouse for $9.4M in 2009.
Twenty Millennium Tower homeowners sued Millennium Partners, San Francisco’s Department of Building Inspection, the city attorney and TJPA alleging fraud and conspiracy to withhold information about the sinking.
The city set a strict deadline for Millennium Partners to answer questions by three independent engineers about the tilt of the building and other forces affecting gravity, stress and settlement and predictions for future settlement. These engineers have been reviewing a number of reports about the structural integrity of the tower.
The homeowners association and Millennium Partners worked toward a strategy to fix the building, but homeowners and the city demanded to know more details. The HOA and developer both said they cannot share details, since it is part of ongoing mediation. Supervisor Aaron Peskin said he would sit in a closed-door meeting if it meant finding out more about the plans to fix the tower.
A new city report concluded the tower is safe for occupancy, though inspectors found evidence the 16 inches of settlement impacted the structure, damaging electrical wiring support systems, and found water damage in the basement. The Department of Building Inspection said most violations have been fixed and ongoing repairs will be reinspected in early February.
One homeowner alleged the tower is not only sinking and tilting, but also stinking. The HOA hired crews to cut open the wall and a draft report revealed stray odors are seeping into the homeowner’s walls and getting sucked into the air ducts.
UC Berkeley engineering professor Jack Moehle told the Government Audit and Oversight Committee that his role on the 2006 peer review board hired by the developer was to evaluate the structural system from top to bottom. That did not include the foundation since that was the job of a geotechnical engineer, and no one had hired one. He said the foundation was up to code and he was not qualified to assess if it worked properly.
Millennium Partners filed legal papers against the TJPA alleging the agency covered up a breach in a $58M protective wall between the tower and the Transbay Transit Center. Millennium accuses TJPA of failing to honor a 2008 agreement to provide compensation for foundation damage.
Records from the San Francisco Public Utilities Commission found half a million gallons of water were drained due to a breach in a cement deep soil mixing wall, but neither filings nor records specify when a breach could have occurred.
The HOA retained Dan Petrocelli, a prominent lawyer best known for winning the civil lawsuit against O.J. Simpson. He also served as President Donald Trump’s lawyer during litigation against Trump University.
CORRECTION, FEB. 10, 3:52 P.M.: A previous version of this story had the wrong measurement for how far the building had settled and was expected to sink over time. The story has been updated.