California Is Sinking
Joseph Poland of the U.S. Geological Survey used a utility pole to document where a farmer would have been standing in 1925, 1955 and where Poland was then standing in 1977 after land in the San Joaquin Valley had sunk nearly 30 feet.
In the 1930s, scientists noticed that the land in the fertile San Joaquin Valley was sinking. The cause was a mystery. No one blamed corporate farmers who in the 1920s had begun massive pumping of groundwater to support the growth of highly profitable but very thirsty crops.
A legendary hydrologist, Joseph Poland, was assigned to solve the puzzle starting in the 1940s. Poland realized that underneath the sinking land, groundwater was being pumped rapidly to irrigate crops. It created massive sinkholes that stretched for miles in every direction. In the farming community of Mendota, the land sank about 30 feet between 1925 and 1977.
The sinkhole is so vast that it is essentially impossible for residents to see that they are standing in one. Poland used a utility pole to build a temporary monument to show them just how much the land had sunk.
The sinking did not slow until the 1970s, after California had completed its massive canal system—the most expensive public works project in state history. It delivered water from wetter parts of the state to farmers in the Central Valley and elsewhere, relieving their reliance on groundwater. The problem was fixed—at least for a while.
An extensive report completed in 2012 revealed the astonishing truth that land was subsiding along the San Joaquin River at a rate worse than during the 1987-92 drought. It was nearing the historic rates of sinking recorded by Poland in the late 1960s. Currently, subsidence (the polite word for sinking) seems to be progressing at the astonishing rate of one to two feet per year in some areas.
There is little political will to confront the wealthy corporate “farmers” who are causing the problem, and the taxpayers quietly pay for repair and replacement of roads and bridges being destroyed by subsidence.
Last year, the state passed its first law attempting to regulate groundwater, but farmers won’t be required to meet goals until 2040 at the earliest. And the information on who is pumping what will be kept private.
The outlook for the future? A scientist with the U. S. geological survey predicts devastation of a historic proportion for California. He says that even if farmers stopped pumping groundwater immediately, the damage already done to aquifers now drained to record-low levels will trigger sinking that will last for years, even decades.