A major construction project aimed at leveling San Francisco's leaning Millennium Tower was abruptly halted this week after officials noticed the building sank another inch in the past month, CBS San Francisco reports.
Work began on the 58-story condo tower, which first made headlines in 2016, earlier this year. The project, expected to cost $100 million, involves reenforcing the foundation by drilling into bedrock below the tower and installing massive support beams, known as pilings, CBS San Francisco reported. The building had actually been sinking less in the past few years – but then began to sink again when work started earlier this year.
"The monitoring has indicated an increased rate of settlement associated with pile installation," Doug Elmets, spokesperson with the Millennium Tower Association, said in a statement to CBS San Francisco. "Out of an abundance of caution, we have placed a two to four-week moratorium on pile installation while we try to understand better the mechanisms associated with the increased settlement rate and available means of mitigating this."
"There has been no material harm to the building and it remains fully safe," he added.
Oakland consulting structural engineer David Williams told CBS San Francisco that the pause was a "no brainer" given the amount the building moved. He said the work has reactivated portions of the settlement below the building, causing it to tilt to one side.
"You may expect a little disturbance when you go in and do construction around it, but the rate of settlement is very severe," he said.
"The loads have to be distributed from the existing foundation out to the perimeter, and that's a pretty risky operation," he added. "It will have to be very carefully monitored if they proceed with it."
Millennium Tower first opened in 2009. By 2016, the building had sunk 16 inches.showed the skyscraper in San Francisco's financial district was sinking at a steady rate.
, and a settlement reached last year included the $100 million for the project.