SAN FRANCISCO (KPIX 5) -- The problem-plagued fix for San Francisco's leaning Millennium Tower is now getting the attention of City Hall.
Last month, excavation work was paused on Fremont Street after engineers discovered the 58-story luxury high-rise had sunk an extra inch and tilted an extra five inches.
Supervisor Aaron Peskin doesn't want it to start back up until a new and independent review panel of experts gets their eyes on the project, and has called for a hearing on the matter.
"I would like there to be a pause until we know what we're doing, and I think that construction should not resume until we can panel the best experts that this country has," said Peskin.
Peskin has been closely monitoring a so-called "perimeter pile upgrade" to prop up the Millennium Tower ever since he first heard about it two years ago.
"The fact that there's been a big setback is, needless to say, very frustrating," said Peskin.
Back then, the Board of Supervisors recruited two geotechnical engineers to review the proposed fix. The experts warned it would cause "further loss of groundwater, which is likely to cause more irreparable damage to the building's substructure."
"It would appear that for whatever reason, that fix may be exacerbating the rate of sinking and tilting, which by all accounts had slowed until this project was undertaken," said Peskin. "I want to get to the bottom of it."
"I can say with confidence that the process and the integrity of the engineering review for this project was sound," said Emily Guglielmo, former president of the Structural Engineers Association of Northern California. "I would trust what is being communicated through the engineers, the review panel, the city, which is to say that there is no cause for alarm, that the building is still capable of withstanding code required loads."
Guglielmo says the current plan to drill 52 new piles down to bedrock on Mission and Fremont streets and then connect them to the building's foundation was vetted by an engineering design review team of top experts.
When asked whether this had ever been done: "I don't know that it's been done with this level of visibility or maybe on this magnitude, but it's definitely a known engineering strategy," said Guglielmo.
But Rune Storesund, a geotechnical engineer and Executive Director of the UC Berkeley Center for Catastrophic Risk Management, is not so sure.
"I don't know a lot about the nuances of the proposed mitigation fix, but I would say it definitely comes across as ambitious," said Storesund. "I'm not sure that we're on the verge of structural collapse. But again, you know, this building is situated in a highly urbanized area. If things did go awry, it would be very catastrophic."
Storesund says it's time for more transparency from the city's Department of Building Inspection.
"Basic stuff like, have you figured it out?" said Storesund. "You know, at what point does the building go from safe to unsafe? I think that transparent process is much more meaningful and comfortable for the public than what we're currently seeing, which is no information."
"The DBI has said in writing that the building is safe and inhabitable. I don't want to take that at face value," said Peskin. "I want that to be independently verified and fact-checked."
Peskin says an independent set of eyes on the project is the best way forward. And no option should be off the table.
"There may come a day when we've got to make the painful decision to perhaps dismantle that building," he said. "Whether we're there yet or not, this panel is going to tell us."
There's still no official word on what caused the recent increased rate of sinking here.
But in response to Supervisor Peskin, a spokesperson for Millennium Tower homeowners' association sent us this update, saying: "Based on monitoring data, the increase in building movement stopped almost immediately after construction was halted and has returned to pre-construction levels of settlement and tilting which has been negligible for several years."
Thursday afternoon, KPIX 5 received a copy of a recent bulletin the HOA Board of Directors sent out to homeowners saying they plan to resume construction shortly. But now there is potential for that to change, with Supervisor Peskin getting involved.
Last month, a settlement was tentatively reached in a lawsuit involving tenants of the sinking building, according to an attorney representing the luxury apartment owners.
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