There’s a new plan to stop Millennium Tower sinking — and settle lawsuits

All sides in the Millennium Tower debacle appear to be nearing an agreement on a $100 million-plus fix to stop the 58-story high-rise from sinking further — but at least part of the building’s tilt will probably remain.

“We’re very encouraged by the recent progress that has been made,” said P.J. Johnston, spokesman for Millennium Partners, the luxury condominium’s developer. “We look forward to working with the homeowners and the city to get this all completed as soon as possible.”

Doug Elmets, spokesman for the homeowners association, cautioned that nothing has been submitted to the city yet for review, but that residents are “encouraged by the ongoing progress.”

The latest plan calls for drilling piles into bedrock from the sidewalk on the building’s southwest corner. The proposal would be less extensive and intrusive than the plan floated in April, which called for drilling as many as 300 micro-piles to bedrock through the building’s concrete foundation.

The idea was to stabilize one side of the 58-story structure, then let the other side continue to sink until the building straightened itself. That plan, however, probably would have cost upward of $350 million — as much as it cost to build the tower in the first place.

The new plan by Ronald Hamburger, the structural engineer for the developer, is expected to be considerably less expensive and faster, and without as significant a disruption to the residents.

“Hopefully, it will take out some of the tilt and stop the building from moving entirely,” said one source familiar with the plan, but who wasn’t authorized to speak for the record.

The tower has sunk 18 inches and tilted 14 inches to the west since it opened in April 2009.

The building sits on a 10-foot-thick mat foundation, held in place by 950 reinforced concrete piles sunk 60 to 90 feet deep into clay and mud. They do not, however, reach bedrock.

The repair job is expected to take several months to complete. The timeline for getting started, however, will probably hinge on how fast the parties can get approval of an environmental impact report and the necessary building permits.

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