The farming town of Corcoran in California’s San Joaquin Valley, USA, began to go underground. From the outside, the changes are not very visible, but they can be well tracked by NASA satellite images, The New York Times reported.
Over the past 14 years, the city has sunk 11.5 feet (about 3.5 m) in some places. According to experts, the reason was blowing of the earth, which occurs when a large amount of water leaves the underground soil, as a result of which the underlying sediments settle.
Every year, the entire 7.47 square miles (roughly 800 ha) of Corcoran, with its 21,960 inhabitants, settle quite a bit as the soil sinks from a few cm to almost 0.6 m. No houses, buildings, or roads are collapsing. The drawdown is not so dramatic, but its impact on the topography of the city is significant, experts say.
The Water Management Agency estimates that the city will sink another 1.8-3.4 m over the next 19 years. Currently, the shells of the wells with drinking water have been destroyed, and the city dam had to be rebuilt for $10 million. According to the US Geological Survey, in Corcoran and other parts of the San Joaquin Valley, land has been gradually but steadily shrinking, largely because agricultural companies have been pumping groundwater to irrigate their crops for decades.