Satellite imaging confirmed that the Millenium Tower in San Francisco is not only tilting but also sinking at a rapid rate every year. People who live in the structure are worried that the building may collapse any time.

According to a report from the European Space Agency, the luxury tower is tilting and sinking for about four centimeters every year. For the past seven years, it had sunk a total of 40 centimeters, a value that has raised some eyebrows in the engineering community. Aside from that, the tower has been tilting at 40 millimeters on average every year since it was constructed.

Now the question on everyone's minds is why and how does a tall structure like the Millenium tilt and sink? According to a report from the Daily mail, there is still no specific cause discovered clearly prove why the structure has behaved as it has.

The most likely cause according to scientists is the possibility that the building has been built on soft soil and the support has not fully rested on stiff soils called a "bedrock."  The area could also be within a liquefaction zone, where water particles in the soil create a quick sand consistency, letting heavy structures settle slowly downward.

Built in 2009, the Millenium Tower in San Francisco is a 58-storey structure developed solely for luxurious residence in the city. One of the tallest structures in the city, people cannot help themselves but be afraid of the possible catastrophe it could bring in case the structure collapses to the ground.

A report from the New York Times has indicated that the local government of San Francisco will be suing the developers of the building. It will be under the claims that they have not informed the buyers about the condition the building is in.