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Toxic Waters in the Gilded State

The 117 mile-long Delta Mendota Canal carries federal CVP water to the San Joaquin Valley. 2010. Photo by Benjamin Preston

To those who have never been, the Golden State is known for luxurious palm tree-lined avenues, sun-drenched beaches, and picturesque mountains. But not all parts of California were created equal. The state’s San Joaquin Valley hosts a scene entirely different from the images of Malibu beaches depicted in travel brochures. It is the non-glittering core of the Gilded State, but it is where a lot of the state’s agriculture lives and where most of its water is used. One of the valley’s more lucrative areas—the 600,000 acres known as the Westlands Water District—is also the seat of an intense debate about agriculture-induced water pollution. Last week, a coalition of environmental and sport fishing groups concerned about the downstream environmental impacts of Westland’s peculiar slurry of ag runoff announced its intention to sue both Westlands and the federal government for violating the federal Clean Water Act.

Driving north from Los Angeles on Interstate 5, the automotive traveler (good luck finding a bus or train route in this region that doesn’t take 30-to-50 percent longer than a car trip) crosses the Tehachapi Mountains, descending into a valley whose bleak flatness makes central Kansas seem exotic. Irrigated fields abound in the vast expanse between the Sierra Nevada foothills and California’s Coast Ranges, but where the irrigation water ends, something resembling a moonscape begins to unfold across the arid landscape. Continuing north along I-5 the traveler might not notice that although the nearby San Joaquin River flows in the same direction, water from the federal Central Valley Project and the State Water Project flow south through concrete-lined canals, pumped uphill from sea level to an elevation of about 500 feet.

The California Aqueduct carries State Water Project water through a 700 mile-long series of pumping stations and concrete-lined channels running north through the San Joaquin Valley. For some of its length, it runs parallel to the Delta Mendota Canal. 2010. Photo by Benjamin Preston

The San Joaquin Valley is a land of superlatives. More oil is produced there than anywhere else in California. Ten of the state’s 36 penitentiaries are in the San Joaquin Valley. Agriculture—especially large corporate organizations—is the region’s top industry. According to a census taken by the USDA’s National Agricultural Statistics Service, California agriculture generated $36.6 billion in agricultural revenue in 2007—nearly 13 percent of the national output. Of that, the San Joaquin Valley—an irrigated oasis filled with grapes, almonds, vegetables, dairy, cotton and other cornucopia items—brought in $27 billion. But that all comes at a cost. The San Joaquin valley doesn’t receive much rainfall most years—Westlands averages about five inches annually. The demand for irrigation water outstripped supply decades ago, so Westlands relies upon the U.S. Bureau of Reclamation’s Central Valley Project to deliver water from distant reservoirs in the more rainy northern parts of the state.

Straddling the imaginary line between Fresno and Kings Counties toward the San Joaquin Valley’s southern end, Westlands Water District is the nation’s largest agricultural water district. Ranging anywhere from 1,200 to 25,000 acres (this despite the fact that federal regulation sets the limit for a single farm irrigated by federal project water at 960 acres), farms within the district’s boundaries tend not to fit the Jeffersonian ideal, but they collectively generate about $1 billion annually. Soil there is good on the surface, but a shallow layer of impervious clay causes the water table to rise quickly once water percolates through crop roots into the ground below. Irrigation runoff releases toxic minerals such as selenium, boron and chromium from the clay, which then flow into the San Joaquin River watershed. Nearly 30 years ago, the U.S. Fish and Wildlife Service began receiving complaints about dead and deformed fish and waterfowl. As agricultural acreage in Westlands has been retired to conserve a shrinking supply of water statewide, farmers there have switched to higher value permanent crops that in actuality use more water. Fish and wildlife contamination downstream continues.

Fallowed permanent crops die, killing often significant investments. San Joaquin Valley farmers are often at odds with regulators limiting water supply for environmental purposes. 2010. Photo by Benjamin Preston

Under natural circumstances, Westlands’ dry acreage would never receive enough rain to release selenium and other chemicals into the river. But intensive production of 470,000 of the district’s 600,000 acres requires pumping more than 1 million acre-feet of water per year to satisfy agriculture’s needs there. A type of salt, selenium occurs naturally in areas that were lake or sea beds much earlier in geologic history. In very small amounts, it is a normal part of cell function, but anything more can lead to cardiovascular dysfunction, skin deformities, and loss of mental function. Five milligrams per day is enough to kill most humans. A study conducted by the U.S. Fish and Wildlife Service at Kesterson Reservoir—once Westlands’ agricultural drain—in the early 1980s found selenium levels higher than 1.4 milligrams per liter. Although the government capped the reservoir with soil during the 1980s, the newer San Luis Drain continues to be a concern for environmentalists and the federal government.

In the coming years, more acreage will likely be retired from Westlands’ agricultural portfolio. But with that change comes other problems. Central Valley Project water rights—the district typically uses more than 700,000 acre-feet of its 1.1 million acre-foot allotment each year—will likely be sold off to other agricultural customers, or to urban consumers in Southern California. A 2004 report compiled by the National Resources Defense Council and the Pacific Institute indicates that ag customers, most likely using water for permanent crops such as almonds and olives which can never be left fallow, would use about 16 percent more energy. Transferring the water to State Water Project contractors in the Los Angeles Basin would increase power consumption eightfold, because it would have to be pumped over the Tehachapi Mountains.

Largescale irrigation in the San Joaquin Valley’s west side was probably not a good idea to begin with. In light of selenium contamination and the high cost of pumping water uphill, it seems that it would have been better to leave it alone. The Westlands Water District serves some small farms, but its cadre of corporate growers is firmly entrenched and politically powerful. The district has levied suits of its own against environmental groups intent on forcing it to release irrigation water downstream to protect endangered fish. Plus, although most of it was built between 1933 and 1979, someone still has to pay for the immense Central Valley Project. As of 2008, the district still owed $373 million, or 75 percent of its long-term debt on the project. Over the coming months and years, the battle between irrigators and conservationists will play out in court. But in the hard, dusty heart of the Gilded State, a dispute over water can be a long, bitter, costly struggle.

Columbia Water Center demonstrates research-based solutions to global freshwater scarcity and climate-related water risks.  Follow Columbia Water Center on Facebook and Twitter

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