The 58-story, 645’ Millennium Tower in San Francisco first started garnering attention in 2016 when it was discovered that the building, which was eight years old at the time, had sank 16” since its completion and was leaning about 2” to the northwest.
Inspectors confirmed the building was safe to live in earlier this year, even after they discovered the building had sank another inch and that its’ lean had grown by a foot. The builders of the Tower, which is the tallest concrete structure in the city, predicted that the building would sink a maximum of 6” over its lifetime.
In addition to long-term stability concerns, residents of the building have recently faced some new, more immediate issues. First, the value of the building’s condos, which sold for between $1.6 and $10 million, have dropped an average of $320,000 since the sinking issue was brought to light. There are also reports of cracks in the basement and malfunctioning elevators stemming from the building’s increasing lean.
More recently, residents experienced large cracks in several windows, which has led some to speculate that the building's facade is beginning to separate from the interior. If this is the case, the building’s poor structural integrity would multiply the effects of an earthquake or fire.
Of course the stakeholders first priority is figuring out who’s at fault and therefore on the hook for the estimated $500 million that will be needed for the proposed solution – digging down deeper to anchor the building to bedrock.
Millennium Partners, the real estate company that built the tower, cites construction of the nearby and recently-completed Salesforce Transit Center as the reason that their building is sinking. They state that too much water was pumped out of the ground during construction of the Transit Center, which caused the sand to compress and their tower to settle. The Transit Center’s developer argues that the Millennium Tower’s issues starting before they even broke ground.