A settlement was just reached over the 58-story skyscraper in San Francisco that's tilting, sinking, and making residents' condos 'worthless'

Beck Diefenbach/ReutersPedestrians inspect cracks near the sinking Millennium Tower in San Francisco, California.

Millennium Tower in San Francisco is still sinking and leaning.

But there’s finally a bit of good news for residents of the luxury building at 301 Mission Street, which has sunk 18 inches and tilted 14 inches since it was completed in 2008.

A tentative settlement was just reached that will require Millennium Partners and Transbay Joint Powers Authority (TJPA) to pay for the $US100m plan to fix the building, according to a report by The Guardian. Residents will also be compensated for their financial losses due to the building’s notoriety.

Though an inspection by the city in 2017 showed that Millennium Tower is safe to occupy, the situation has motivated some people to bail out. Residents previously said they sold their homes short of what they paid for them, with about 100 condos falling $US320,000 in value on average in 2017.

Here’s what we know about Millennium Tower.

Millennium Tower rises 58 stories above San Francisco’s Financial District.

Vanguard PropertiesMillennium Tower.

The city’s third-tallest skyscraper contains over 400 multimillion-dollar condo units. It soars 645 feet, giving residents panoramic views of the San Francisco Bay Area.

Jacob ElliottA view of San Francisco from the grand penthouse at Millennium Tower.

Source: Emporis, Dezeen

Completed in 2008, Millennium Tower includes top-notch amenities, such as a pool, fitness centre, wine cellar and tasting room, movie theatre, and concierge service.

Vanguard PropertiesThe pool inside Millennium Tower.

Source: Millennium Tower

In the first five weeks of sales, Millennium Tower sold $US100 million worth of condos, the San Francisco Chronicle reported. The units ranged in price from $US1.6 million to $US10 million.

Jacob ElliottThe grand penthouse at Millennium Tower sold for $US9.4 million in 2009.

Source: San Francisco Chronicle (1), (2)

Famous tenants have called Millennium Tower home, including Joe Montana, the former San Francisco 49ers quarterback, and Tom Perkins, the late venture capitalist.

APSan Francisco 49ers quarterback Joe Montana flashes a confident grin as he warms up prior to the start of Super Bowl XIX, Sunday, Jan. 20, 1985 in Stanford, Ca., at Stanford Stadium.

Source: Business Insider

But residents weren’t happy after learning in 2015 that the building is sinking. By 2018, the building sunk 17 inches and tilted 14 inches.

Justin Sullivan/GettyA person walks by the Millennium Tower on August 11, 2016 in San Francisco, California.

Millennium Partners, the real-estate developers behind Millennium Tower, have claimed that construction on a massive transit centre nearby is to blame for any sinking or tilting.

Justin Sullivan/GettyThe Salesforce Tower is reflected in the glass panes of Millennium Tower.

Source: NBC Bay Area

A transportation hub called the Salesforce Transit Centre, formerly known as the Transbay Transit Centre, broke ground next door in 2010.

Google Earth; Melia Robinson/Business InsiderMillennium Tower and the Salesforce Transit Centre.

Source: Business Insider

The $US2.3 billion bus terminal, developed by the Transbay Joint Powers Authority, a transportation agency, includes a 60-foot hole for the train tunnel and an underground buttress.

Eric Risberg/APIn this Dec. 3, 2010 file photo, a wrecking ball at left takes some of the first swings against the front facade of the old Transbay Terminal building in San Francisco.

Source: San Francisco Business Times

A founding partner of Millennium Partners said at a press conference that there was “only one issue” — construction for the new terminal pumped too much water out of the ground.

Eric Risberg/APA wrecking ball takes some of the first swings against the front facade of the old Transbay Terminal building in San Francisco, Friday, Dec. 3, 2010.

Dewatering is removing groundwater or surface water from a construction site to provide a safe work environment and prevent soil erosion.

When the water levels under the Millennium Tower dropped, the sand compressed and caused the building to settle, according to Chris Jeffries, a founding partner of Millennium Partners.

The issue came to light in 2010, five years before tenants were notified, when the Transbay Joint Powers Authority hired a consultant to find out how excavation could affect the tower.

The Transbay Joint Powers Authority maintains it is not at fault in the building’s sinking.

Lorin Eleni Gill/APThe Transbay Transit Centre, which reopened this past July.

The agency released a statement in October condemning the allegations against it as a “distraction from the exclusive cause” of the tower’s tilt: “inadequate foundation.”

The statement says Millennium Tower’s vertical settlement began two years before the Transbay Joint Powers Authority began any underground work.

Read more: San Francisco’s new $US2.3 billion transit centre could be the most expensive bus terminal in the world »

Some critics blame city officials in San Francisco for allowing Millennium Partners to anchor the building 80 feet into packed sand rather than 200 feet down to bedrock.

Wikimedia CommonsMillennium Tower under construction.

Millennium Tower sits on an array of nearly 1,000 pillars shoved into the ground.

Its weight, combined with the resistance of the soil underneath, should keep it in place under most conditions, a professor of architectural design told real-estate site Curbed.

The design isn’t all that unusual. Some of the city’s best-known buildings, including the Embarcadero Centre and the San Francisco Museum of Modern Art, were built on sand instead of bedrock.

The biggest cause for concern is the looming possibility of an earthquake.

Simon Baker/ReutersSewage spreads past a car trapped in a sinkhole caused by liquefaction in a New Zealand suburb after a 5.8-magnitude earthquake struck in 2011.

For years, scientists have warned that the Bay Area is overdue for a devastating earthquake.

Millennium Tower sits on land prone to liquefaction, the process by which loose sand and silt behave like a liquid in the event of an earthquake. The seismic activity causes water pressure in the sediment to increase and grains of sand to lose contact with each other,according to the US Geological Survey. The soil may give out under large, heavy structures.

Often, the solution for tall buildings in liquefaction zones is drilling down to bedrock. Millennium Tower’s neighbours, the $US1.1 billion Salesforce Tower and the luxury high-rise 181 Fremont, are both anchored to bedrock. They’re still under construction.

There’s good news and bad news for residents. A study released in January 2017 by the city’s Department of Building Inspection found that the skyscraper was safe to live in.

Eric Risberg/APA team of engineering geologists examining soil samples taken outside Millennium Tower.

“There was no evidence of life-safety concerns observed during the inspection,” the report said.

Satellite images taken in 2016 that show Millennium Tower sinking suggested it will continue to sink at a rate of 2 inches a year. That’s double what engineers estimated.

European Space AgencyData from the European Space Agency’s Sentinel-1 satellites shows that Millennium Tower is sinking by about 40 millimetres a year in the direction they’re looking at the building.

Source: Business Insider

Gaps found in the walls of some units could also present risks in the event of a fire, according to a report commissioned by the building’s homeowners association.

Jacob ElliottA view of San Francisco from the grand penthouse at Millennium Tower.

In 2017, the building’s homeowners association hired the firm Allana Buick and Bers to investigate a unit owned by Paula Pretlow. She and several other residents had complained of “unexplained odours permeating their luxury units,” NBC Bay Area reported.

The consultants discovered openings around pipes and ducts in the walls. Typically, gaps like these are sealed with fire-resistant caulking to contain fires where they start.

If a small fire were to break out in the unit below Pretlow’s, the flames could more easily spread to her condo, or smoke could damage the walls, according to NBC Bay Area.

The report pertained only to Pretlow’s unit, though others could be susceptible.

A group of Millennium Tower residents fought to get their money back — and it appears they have succeeded.

AP/Eric RisbergJerry Dodson and his wife Pat stand inside their home on the 42nd floor of the Millennium Tower in San Francisco.

Roughly 250 tenants filed individual lawsuits against developer Millennium Partners and Transbay Joint Powers Authority, while the remaining 150 filed class-action lawsuits. According to Niall McCarthy, who spoke with the San Francisco Examiner, residents are set to receive “very significant payments” as a result of their losses due to the building’s notoriety and loss of property value.

On August 30, a $US100 million plan to stabilise the building with a “perimeter pile upgrade” was reported to be approved. According to the San Francisco Examiner, the process of stopping the building from sinking any further involves drilling “52 concrete piles down to the bedrock” in order to secure the tower’s corrupted foundation.

Source: San Francisco Examiner

A date for the repairs has not been released as of yet. However, this tentative settlement marks a turning point for residents.

Justin Sullivan/GettyA person walking in front of Millennium Tower.

The stigma and notoriety of the building, however, may stick, says Niall McCarthy, a legal attorney representing a group of Millennium Tower homeowners.

“Even with the fix, there’s still going to be some stigma to the property,” he said. “You see tour buses go down Mission Street that stop and point out Millennium Tower. At some point, when these people try and resell their units, the stigma from the sink and tilt will reduce the value of what it should be.”

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