In California, Demand for Groundwater Causing Huge Swaths of Land to Sink.

http://news.nationalgeographic.com/news/2014/03/140325-california-drought-subsidence-groundwater/

The article talks about the very common issue in the USA and the world which is the pumping of underground water leading to sink-age of land. This issue is a very common one in Florida, in which recently a hotel sunk in the ground.

This issue is a common one in the San Joaquin, from 1930 to 1970 the ground level sank by around 9 meters (USGS report). As groundwater supplies 1/3 of water to California even more in drought seasons, underground pumps are built in order to extract water and supply all the counties with water. In the subsidence, an investment of over 800 million needs to be conducted in order for the restoration of the San Joaquin River to be restored. Recently a survey has been conducted related to the sink ages in which USGS thought that their data was wrong because the land had settled so much as Rick Woodley the bureau resource manager. Many construction sites that were near the river were delayed due to the restoration. 

However, this issue is not only present in the USA, it is occurring more and more in Russia and its neighboring countries. 


These causes are not due to water extractions, but may be the cause from various floods or chemical dissolution of carbonate rocks.