New satellite imagery reveals sinking Millennium Tower

By David Jacobson, Temblor

Check your seismic hazard

The European Space Agency (ESA) recently released new satellite imagery, that reveals which parts of the Bay Area are subsiding and those that are being uplifted.

This map shows how much of the Bay Area is moving. Warmer colors represent areas of subsidence, while cooler colors show uplift. (Image courtesy of ESA)

In addition to being able to look at the region as a whole, the Sentinal-1 satellite data allows people to examine more specific areas. Of primary interest to many in the Bay Area, is the sinking Millennium Tower, also known as the Leaning Tower of San Francisco.

Map of movement in San Francisco. While much of the city has seen very little uplift or subsidence in the last 17 months, the area around the Millennium Tower, and the Mission Bay area show significant subsidence according to data provided by by European Space Agency. (Image courtesy of the ESA)

The Millennium Tower has been in the public eye ever since reports showed that it has sunk significantly since its completion in 2009. This new satellite imagery shows this, and ESA scientists say that the rate of sinking may be double what initial reports by independent contractors suggested. In the image below, the Millennium Tower can be seen. Additionally, large portions of Mission Bay are also showing signs of subsidence.

According to European Space Agency scientists, the data from the Sentinel-1 satellites show that the Millennium Tower may in fact be sinking twice as fast as initial reports suggested. The data processed by the ESA show that it may be sinking by as much as 40 mm per year. In addition to the Millennium Tower sinking, this data also appears to show that adjacent buildings may also be suffering from subsidence. However, this has not been confirmed. (Image courtesy of the ESA)

While the Millennium Tower stands out in this study and garners public attention, the purpose of the European Space Agency compiling this data is to track urban global movement, in particular, subsidence in Europe. Having said that, the Bay Area was given extra attention because of interest in movement along the Hayward Fault at the base of the Berkeley Hills. In order to calculate the movement seen in this imagery, satellite data was recorded every 24 days, over the course of 17 months.

European Space Agency (ESA)
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