How to Prevent Your Own Millennium Tower Slump


By: Daniel A. Nicholson
The affluent inhabitants of San Francisco’s Millennium Tower may be experiencing a sinking feeling as the first lawsuits concerning the tower’s reported sixteen inch drop and two inch tilt were filed last Tuesday. Residents claim that foundation problems may sink their property values as reports from geotechnical engineers indicate the tower could fall an additional eight to fifteen inches and develop a worse tilt.
Millennium Partners constructed the tower from 2005 to 2009, choosing a residential style concrete-frame instead of the usual steel-frame for its 58-stories. This decision created a heavier building than most of its neighbors, an interesting choice for a building built just off San Francisco Bay’s original coastline on unstable mud-fill.
Residents claim that Millennium Partners cut corners when they anchored the building only eighty feet into landfill, instead of driving it down into bedrock two-hundred feet below. Millennium counters that an accelerated rate of settlement coincides with the construction of the Transbay Transit Center which includes a half-mile tunnel sixty feet underground bordering the tower. The Transbay Joint Powers Authority, developer of that project, spent $58 million on an underground buttressing system to prevent damages before they began excavation, but Millennium contends that wasn’t enough. Residents have filed suit against both Millennium for negligent construction, and the Transbay Joint Powers Authority for contribution.
While experts have claimed that the current state of the building isn’t a cause for serious concern, the Millennium Tower is the tallest reinforced concrete structure situated in a Seismic Zone 4 Region. With San Francisco’s propensity for violent seismic activity and the towers location on top of landfill it could become a concern rather quickly. Liquefaction, a reaction where loose soil begins to behave like liquid during an earthquake, could cause significant sinking and damage. In fact, it may have been a factor in the tower’s current drop.
The Millennium Tower slump is a good reminder of two important lessons:
First, always measure twice, and cut once. Not thoroughly planning and preparing before you take action can cost you significant time and money in the long run. Although it is hard to say what actually caused the tower to sink these possibilities should have been considered in the planning and preparation stages beforehand. On the legal side, proper planning starts well before the first contracts are signed, appropriately allocating the responsibilities, duties, and liability of the parties involved just in case your project starts a Millennium Tower slump. The parties here face extensive costs, both in the actual repair and mitigation of the shifting of the tower, but also in the legal fallout that will result. Understanding all the variables, whether environmental or legal, that will affect your construction project is a critical step before breaking ground.
Second, never cut corners. If the allegations against Millennium Partners are true the amount of money they will have saved not properly anchoring the tower will pale in comparison to the amount they will end up paying in order to rectify it. The same applies to Transbay Joint Powers Authority if they cut corners protecting the integrity of the tower during their excavation. Both parties could face immeasurable damage to their own and their contractor’s reputations. In construction, as in legal work, it is critical that the job is done right the first time, on time.