KCBS_740 SAN FRANCISCO (KCBS) — The troubles of Millennium Tower have city officials promising to change.

Supervisors grilled building inspection officials Thursday about the 58-story, luxury condo tower South of Market that is sinking more than expected.

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Supervisor Aaron Peskin led the audit and oversight committee in questioning the Department of Building Inspection about the tower.

DBI asked for, but did not peer-review the safety analyses of hired experts on the project.

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“The building is not performing as we thought it was going to perform, so it really raises a much larger public policy issue. This is not, someone’s toilet is leaking on Taraval Street, this is a big deal in a seismically-prone town – don’t we have a protocol, or do we need an internal protocol that says we will independently verify this?” Peskin said.

The first concerns about the building were raised in 2006 when the city expressed concern that the foundation design might not support the weight of a 58 story concrete tower, but the city allowed construction to proceed.

Then, serious concerns were raised in 2009 when the department sent a letter to the builder, explicitly asking about the sinking foundation and what was being done about it.

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Just like 2006, nothing was done in 2009 – and the conversations simply stopped.

Instead, after internal discussions about the building’s safety in 2006 and 2009 – it took an anonymous 311 call in 2016 for the city to publicly acknowledge that the building is – in fact – sinking. And, as of Thursday night, no one can explain how that happened.

“I am just fixated on getting to the bottom of that,” Peskin said.

Deputy Director of the Department of Building Inspection Ron Tom told Peskin that they are changing the way they do things.

“We’re not going to be only dependent on the letters of confirmation from the owners’ design professionals. We’re going to well up a system of checks and balances that goes beyond our own department’s expertise,” Tom said.

The owners of Millennium Tower are expected to hire their own design consultant by the end of the month to report to DBI on its stability.

Those owners have said the tower is safe.

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