Historic 1977 photo of Dr. Joseph Poland, USGS, considered the pioneer of scientific subsidence studies. Dates on telephone pole indicate previous land elevations in an area SW of Mendota. Photo credit: U.S. Geological Survey
Next time you eat food grown in the San Joaquin Valley of California, think about this: the water used for growing them probably came from under ground. Farmers do not really have a choice because the amount of water from rain and snow can’t keep up with the needs for growing food. Every year more water is drawn out of the ground for irrigation. Because of this, the floor of the San Joaquin Valley goes down as the sediments compact once the water is out (see picture on right).
In the latest work from our team, we find a surprising side effect of groundwater pumping: the…
View original post 224 more words