Ohenhen has been analyzing subsidence rates in the US for the past year, and in a new study he and his team show that urban areas with 98 percent or more sinking land include Chicago, Dallas, Columbus, Detroit, Fort Worth, Denver, New York, Indianapolis, Houston, and Charlotte.

The nation's biggest cities are sinking, according to data from a new study. Known scientifically as land "subsidence," the most common cause of the sinking is "massive ongoing groundwater extraction,