Mar 17 2014
California’s Unsustainable Central Valley
Sustainable is the buzz word ubiquitous in Green literature. It is defined in the Merriam Webster Dictionary: “as of, relating to, or being a method of harvesting or using a resource so that the resource is not depleted or permanently damaged“. In the Great Central Valley of California the water systems and socio-economic model that have existed for just half a century are not sustainable.
No matter how much money is thrown at the current water issues, the words of John Wesley Powell were never truer. They are quoted from the book Dead Pool, and included in the first few pages of Water Shock.
At an 1893 Irrigation Congress in Los Angeles, after listening for several days to those who proclaimed the vast wealth of an irrigated West, [John Wesley Powell] rose to speak, saying:
“When all of the rivers are used, when all of the creeks in the ravines, when all the brooks, when all the springs are used, when all the reservoirs along the streams are used, when all the canyon waters are taken up, when all the artesian waters are taken up, when all the wells are sunk or dug that can be dug in all this arid region, there is still not sufficient water to irrigate all this arid region.”
It was merely simple arithmetic, he said.
“If you need twenty-four inches of water a year to grow crops on an acre-foot of land, and Nature supplies three, four, or five inches of rainfall, even if you catch every drop it will not be nearly enough.”
Take a look at this statistic. From 1962 to 2002, the vast aquifer under the Central Valley was depleted by seventy million acre-feet. The water in that aquifer is millions of years old. How much water is that? It is seventy million football fields covered a foot deep in water. Stacked on top of each other, the stack would reach 13, 257 miles high, equivalent to half the circumference of the earth. Refer to the 2009 paper titled Groundwater Availability of the Central Valley Aquifer, California by the USGS1
If it wasn’t so revealing about the unsustainable situation Californians and those who depend on Central Valley agriculture, the 225 pages document could take the place of sleep-inducing medication. It is worth it, however to plow through the paper.
Another statistic you will find in the document is current withdrawal rates of water are exceeding two million acre-feet a year, and the rate of withdrawal is rising. Part of the State Water Project is used to recharge the Central Valley Aquifer, however as near as I can tell, that seventy million acre-feet was never replaced. And recharging volumes do not make up for the water being withdrawn.
The indisputable fact is the water systems put in place in the mid-1950’s cannot sustain the Central Valley’s socio-economic conditions. They never could actually.
If your mind is spinning trying to comprehend these enormous figures, you have a lot of company. Let’s bring it down to common experiences. The gas tank in the average car holds about twenty gallons. If we start on a 2500 mile trip across the US, at twenty miles per gallon we can travel about four hundred miles. If the tank cannot be refilled, our trip is over. Our trip and fueling plans were unsustainable. Growing crops in the Central Valley with an annual rainfall of about six inches is absolutely unsustainable.
If John Wesley Powell were alive today, he might say, “I told you so over a hundred years ago”. The leadership task is not how to get more water to the Central Valley by spending billions on forty-foot diameter, thirty-two mile-long tunnels under the Delta. It is how to undo this monumental mistake in the Great Central Valley where three million people try to make a living. This problem has a human face on it. The pain of relocation will be felt by ordinary people and agri-business alike.
1 Faunt, C.C., ed., 2009, Groundwater Availability of the Central Valley Aquifer, California: U.S. Geological Survey Professional Paper 1766, 225 p —————
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