Monday 12 June 2023

Leaning Tower of San Francisco: No Competent Engineers left in the Bay Area?

Leaning Tower of San Fran? Workers scramble to fix Millennium Tower as the $350million luxury building continues to sink deeper into old Bay Area landfill

  • San Francisco's Millennium Tower continues to tilt even as construction crews scramble to stabilize the luxury building
  • The building, which opened in 2019 and quickly sold out all of its units, had sunken 16 inches by 2016 and begun to tilt to the west 
  • Part of a settlement with the tenants, who sued, was $100million to stabilize the structure

The Millennium Tower in San Francisco is sinking, which is causing it to tilt to the west, despite the efforts of workers scrambling to attempt to fix the problem with the luxury high rise.

According to reports, the tower is currently leaning more than 29 inches at the northwest corner, with much of that lean occurring during the digging phase of the plan put in place to eventually support the tower along its sides. 

Engineers saw signs of progress earlier this year when six concrete-filled steel pilings were implemented along the base of the $350million building, but that effort may have led to the new amount of tilt assumed by the sinking tower that was built on a former landfill.

The result of the lean has been leaking and crumbling walls in the facility's below-ground parking garage, while residents live above. 

Workers repair crumbling walls that have been the result of leaking water in the garage of the Millennium Tower in San Francisco

Workers repair crumbling walls that have been the result of leaking water in the garage of the Millennium Tower in San Francisco

Engineers running the project now claim that data implying the tilt has increased may not be reliable, despite previously relying on it to support their claims of early success with the project. 

The lead engineer of the project, Ron Hamburger, told NBC  the data taken from rooftop measurements are prone to weather fluctuations and that data taken from the building's foundation is more reliable.

Data from the building's foundation also indicates that the current tilt is more significant than previously noted, though only by about a quarter of an inch, an amount Hamburger claimed was 'negligible.'

'We are fully confident that following transfer of the remaining design load to the piles,' said Hamburger, adding that 'there will be no further … movement of the roof to the west.'

Hamburger said he and his team next plan to secure the foundation of the building to 12 pilings sunk along Fremont Street that will bear the partial weight of the building load.

Veteran geotechnical engineer Bob Pyke, who has long been a doubter of the $100million plan to fix the leaning tower, feels considerably less optimistic about the next stage of the project.

'As far as remedial work goes, this is just a mess. You spend all this money, but you still have an uncertain result long term,' he said.

Pyke says there is no way to know if fixing the tower will work as hoped and stop tilting after some of its weight is shifted to the piles rooted in the bedrock.

'The design team has always claimed that there is going to be some rebound after they connect the perimeter piles. So far the evidence seems to suggest that’s not going to happen,' he said. 

The plan as it stands at the moment is to have the building load partially shifted to those piles inside of the next several days.

The effort to stabilize the building and stop the sinking and leaning has been going on since the spring of 2021.

Millennium Tower on Mission Street in San Francisco's Financial District. The building opened in 2009 and by 2016 had sunken 16 inches

Millennium Tower on Mission Street in San Francisco's Financial District. The building opened in 2009 and by 2016 had sunken 16 inches

A stress gauge is seen on a wall with floor-to-ceiling cracks in the parking garage of the Millennium Tower

A stress gauge is seen on a wall with floor-to-ceiling cracks in the parking garage of the Millennium Tower

A stress gauge on the wall of the tower's storage area, where floor-to-ceiling cracks developed

A stress gauge on the wall of the tower's storage area, where floor-to-ceiling cracks developed

By 2016, the building (to the right of the tallest building) had sunk nearly a foot-and-a-half into the soft soil and landfill upon which it was built. Residents of the building subsequently sued the developer and designers

By 2016, the building (to the right of the tallest building) had sunk nearly a foot-and-a-half into the soft soil and landfill upon which it was built. Residents of the building subsequently sued the developer and designers

The luxury 58-story tower opened in 2009 and quickly sold out its 419 apartments, with buyers including former San Francisco 49er Joe Montana and former Giants outfielder Hunter Pence. 

By 2016, the building had sunk nearly a foot-and-a-half into the soft soil and landfill upon which it was built in San Francisco's financial district.

It was also leaning, creating a two-inch tilt at the base, and a 6-inch lean at the top. Residents of the building subsequently sued the developer and designers. 

A confidential settlement reached several years ago included $100million to install 52 concrete, 140,000-pound piles to anchor the building to bedrock located 250 feet below ground, with the idea that the piles would provide foundational support to the leaning, sinking tower.

The city should buy it then move all the street dwellers and druggies into the empty apartments. Then they won't care if it topples! Two problems solved in one swoop.

The foundation piles were recommended to go twice as deep, to 250' bedrock, but they built them only to 90'.

The lavish Millennium Tower in San Francisco has tilted an additional four inches since summer

The lavish Millennium Tower in San Francisco

It is now tilted 26 inches and has sunk up to 18. Structural engineer Ronald O. Hamburger has now suggested the building lose more than half of the support beams under the structure, going from 52 to 18 to 'minimize additional building settlement'

It had tilted 26 inches and had sunk up to 18 by 2016

Earlier this summer, stabilization work was halted after the holes for the support beams were determined to be too big and had cause soil movement

At one point stabilization work was halted after the holes for the support beams were determined to be too big and had caused soil movement

The ritzy building is 58 stories high and is 645 feet tall

The ritzy building is 58 stories high and is 645 feet tall 

It comes with a pool, spa, in-house cinema, and a restaurant

It comes with a pool, spa, in-house cinema, and a restaurant 

An estimated 100 condos have lost $320,000 in resell values due to the sinking

An estimated 100 condos have lost $320,000 in resell values due to the sinking

Jerry Dodson and his wife Pat stand inside their home on the 42nd floor of the Millennium Tower in San Francisco which has begun to lean

Jerry Dodson and his wife Pat stand inside their home on the 42nd floor of the Millennium Tower in San Francisco

City Hall Supervisor Aaron Peskin attends a public hearing at City Hall he called to determine why the Millennium Tower is sinking and why its structural problems were kept quiet for years 

City Hall Supervisor Aaron Peskin attends a public hearing at City Hall he called to determine why the Millennium Tower is sinking and why its structural problems were kept quiet for years 

Apartment #55A (pictured) at Millennium Tower, dubbed the 'leaning tower of San Francisco', has gone on the market for almost double what the current owner paid in 2011, at $3.23 million

Apartment #55A (pictured) at Millennium Tower, dubbed the 'leaning tower of San Francisco', has gone on the market for almost double what the current owner paid in 2011, at $3.23 million

The 2,706-square-foot two-bedroom, three-bath unit features an open-plan kitchen, living, and dining room and generous walkways

The 2,706-square-foot two-bedroom, three-bath unit features an open-plan kitchen, living, and dining room and generous walkways

Floor to ceiling windows help make the best of the apartment's 55th story views over the Bay Area

Floor to ceiling windows help make the best of the apartment's 55th story views over the Bay Area

 Gregg Lynn, a sales broker for #55A, said that the current owners have spent lots of money on an extensive renovation 

 Gregg Lynn, a sales broker for #55A, said that the current owners have spent lots of money on an extensive renovation 

The contemporary, luxurious decor may go some way to explain why the owners of the apartment in a building sinking inches every year has upped their price

The contemporary, luxurious decor may go some way to explain why the owners of the apartment in a building sinking inches every year has upped their price

One of the bedrooms, in the two-bed apartment, offers stunning views over San Francisco

One of the bedrooms, in the two-bed apartment, offers stunning views over San Francisco

The building also offers a concierge, a resident¿s lounge with flat screens  and an open fire (pictured)

The building also offers a concierge, a resident’s lounge with flat screens  and an open fire (pictured)

The luxury doesn't stop there, as it also has an indoor pool and fitness center, and a private dining room for residents 

The luxury doesn't stop there, as it also has an indoor pool and fitness center, and a private dining room for residents 

The Millennium Tower (pictured above), dubbed by locals as the Leaning Tower of San Francisco, has been the focus of several lawsuits over the last seven years involving the developer, the city and owners of its multi-million dollar condos

The Millennium Tower (pictured above), dubbed by locals as the Leaning Tower of San Francisco

The building's movement has caused cracks in the sidewalk outside, as well as cracks in the basement level 

The building's movement has caused cracks in the sidewalk outside, as well as cracks in the basement level 

The building's developers have blamed the issue on the construction of the new Transbay Transit Center across the street. Above, some moved marble at the building

 some marble at the building which has moved

Transit officials say the accusations are 'misplaced' and that the reason for the movement is due to Millenniums shallow foundation, which was built on sand and not into the bedrock. Above, a look inside one of the building's units

officials say that the reason for the movement is due to Millenniums shallow foundation, which was built on sand and not into the bedrock. Above, a look inside one of the building's units

Units in the building go for as much as $10million. NFL legend Joe Montana and San Francisco Giants star Hunter Pence have apartments in the building 

Units in the building go for as much as $10million. NFL legend quarterback Joe Montana and San Francisco Giants baseball star Hunter Pence have apartments in the building 

Experts say that the movement is a cause for concern but should not make the building any more at risk for damage in an earthquake

Experts say that the movement is a cause for concern

The luxurious high-rise has been suffering from many structural issues since it opened in 2009, including water-damaged (pictured) and stress fissures on the 38th floor

The luxurious high-rise has been suffering from many structural issues since it opened in 2009, including water-damage (pictured) and stress fissures on the 38th floor  

The gorgeous building offers its residents beautiful views of the city with luxurious, open space and unobstructed views over San Francisco Bay

The gorgeous building offers its residents beautiful views of the city with luxurious, open space and unobstructed views over San Francisco Bay 


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