Tuesday, August 2, 2016

Luxury skyscraper Millennium Tower sinking and tilting in downtown San Francisco




Some of San Francisco's wealthiest tenants are being reassured their high-rise building is a safe place to live after learning the Millennium Tower is sinking and tilting. (KGO-TV)




Some of San Francisco's wealthiest tenants are being reassured their high-rise building is a safe place to live after learning the Millennium Tower is sinking and tilting.

The 58-story building is a condominium skyscraper located on Mission and Fremont streets. It has been voted by some as one of the top 10 residential buildings in the world.


According to an independent consultant hired to monitor the problem, the residential building has sunk 16 inches since its completion in 2008. It has also tilted 2 inches. "There are some cracks in the wall in the parking garage and there's been some settling on the club level floor," said Pat Dodson, a Millennium Tower homeowner.

One Yelp review noticed windows and a dishwasher getting harder to open and bubbles appearing in the floor.

In July, the homeowners' association brought in an engineer. "Why the building is sinking and tilting. It's very clear after listening to him and doing a lot of research, which my husband and I have done, that Millennium Partners did not build to bedrock, and that's the cause of the problem," explained Dodson.

The owners are pointing the finger at their neighbor. They allege the massive hole dug next door for the new Transbay Transit Center is to blame for the building's issues.

A spokesman for Millennium Partners issued a statement saying: "All buildings settle over time. 301 Mission has settled more than originally anticipated because it was affected by subsequent construction by others."

The Millennium Tower association released a statement saying: "It will take all necessary steps to ensure that the buildings are fully repaired and that all parties that caused or contributed to the settlement conditions are held legally accountable."


The Transbay Joint Powers Authority responded by saying residents' claims against the TJPA are "misplaced" as demonstrated by data collected over more than seven years.

They went to say, "full responsibility for the tilting and excessive settlement of the building lies with Millennium Partners, the developer of the Tower."

The TJPA says the 60-story Millennium Tower is made of concrete rather than steel, "resulting in a very heavy building. This heavy structure rests on layers of soft, compressible soil. The foundation of the Tower, however, consists only of a concrete slab supported by short piles that fail to reach the bedrock below. That foundation is inadequate to prevent settlement of a building with the weight of the Tower."

Instead of steel anchored on bedrock more than 200 feet down, it's made of concrete, sitting on a slab with pilings just 80 feet into the soil.

The Transbay project environmental document was approved in 2004. When Millennium Partners started construction of the Tower in 2006, they knew that the TJPA intended to excavate adjacent to their building, according to the TJPA. 


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For Immediate Release



Media Contact:

Scott Boule

Office: 415-597-4620

 sboule@transbaycenter.org



Transbay Joint Powers Authority Denies Responsibility for Tilting and Excessive Settlement of the Millennium Tower at 301 Mission Street, San Francisco



San Francisco (August 1, 2016)In June, the TJPA received claims for damages from certain residents of the Millennium Tower located at 301 Mission Street. The claims seek to hold the TJPA responsible for the tilting and excessive settlement of that building. The residents’ claims against the TJPA are misplaced; as demonstrated by data collected over more than seven years, full responsibility for the tilting and excessive settlement of the building lies with Millennium Partners, the developer of the Tower.



The 60-story Millennium Tower is made of concrete rather than steel, resulting in a very heavy building. This heavy structure rests on layers of soft, compressible soil. The foundation of the Tower, however, consists only of a concrete slab supported by short piles that fail to reach the bedrock below. That foundation is inadequate to prevent settlement of a building with the weight of the Tower. In contrast, the Salesforce Tower and 181 Fremont Tower, also adjacent to the Transit Center, are supported on piles drilled down to bedrock. Millennium Partners’ poor design decision is the cause of the tilt and excessive vertical settlement of the Millennium Tower.



The Transbay project environmental document was approved in 2004. When Millennium Partners started construction of the Tower in 2006, they knew that the TJPA intended to excavate adjacent to their building. Nonetheless, Millennium elected short piles that did not reach bedrock. The engineers who designed the foundation for the Millennium Tower predicted that the Tower would settle vertically a maximum of six inches over the life of the building. By the time the TJPA started work on its project in 2010, the Millennium Tower had already settled ten inches – four more inches than Millennium’s engineers predicted over the life of the building. The building has continued to settle vertically, now 16 inches, even after the TJPA completed the excavation for the Transit Center.  A foundation of piles down to bedrock would have prevented this vertical settlement.



As for tilt, by August 2010, before the TJPA started any work on its project, the Tower was already tilting to the north, away from the former Transbay Terminal.  Although the Tower straightened slightly during the TJPA’s excavation for the underground levels of the Transit Center, the Tower never tilted past vertical toward the Transit Center.  The Millennium Tower is currently tilting toward the west and northwest, away from the Transit Center, and that west/northwest tilt is increasing.  Again, had Millennium Partners invested in piles extending to bedrock, the Tower would not be tilting today.



Aware that the Millennium Tower foundation failed to reach bedrock and was therefore inadequate to support the Tower, the TJPA took the extraordinary step of spending more than $58 million to install an underground buttress between the Millennium Tower and the Transit Center site before the TJPA began its excavation for the new Transit Center. The buttress consists of 181 overlapping reinforced concrete piles, each seven feet in diameter and drilled to bedrock. The buttress protects the soil under 301 Mission from movement in response to work on the Transit Center. Geotechnical monitoring data has been collected by the TJPA and consistently provided to Millennium Partners since April 2009. This monitoring data demonstrates that the buttress was entirely effective in preventing excessive movement of the Tower due to the excavation for the Transit Center. Again, the TJPA completed the buttress and excavation of the Transit Center several years ago, yet the Millennium Tower has continued to settle at a steady rate due to the Tower’s own improper foundation. The TJPA’s monitoring of other nearby tower developments confirms that no other neighboring towers are experiencing excessive settlement like the Millennium Tower.



Because the TJPA has shared with Millennium Partners its data monitoring the Tower’s settlement and the causes of the settlement, Millennium Partners has been fully aware of the extent of, and reasons for, the Tower’s unusual settlement. The TJPA has no knowledge as to whether Millennium Partners communicated that information to the building’s residents, either before or after they purchased their condominiums from Millennium.



About the Transbay Transit Center



The Transbay Transit Center, known as the “Grand Central Station of the West,” is a

revolutionary transportation facility that will transform the South of Market neighborhood into

the new heart of downtown. The Transit Center will connect eight Bay Area counties and 11

transit systems, including future High Speed Rail. The Transbay Transit Center Phase 1 is

scheduled to open at the end of 2017. To learn more about the project, please visit our website at

www.TransbayCenter.org.



The Transbay Transit Center project is made possible in part by the U.S. Department of

Transportation, State of California, Metropolitan Transportation Commission, Proposition K

Sales Tax dollars provided by the San Francisco County Transportation Authority, City and

County of San Francisco, San Francisco Office of Community Investment and Infrastructure,

San Mateo County Transportation Authority and AC Transit.



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