Kesterson Reservoir (site)

 agriculture, nature conservation park / area

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Kesterson Reservoir is located about 10 miles southeast of Newman, California, at the eastern end of Gun Club Road off Highway 33.
It was the site of an ecological disaster in the mid-1980's. The 1,300 acre site was used as a terminal reservoir for the San Luis Drain, and became an evaporation pond for agricultural drain water from Westlands Water District. The drain water contained salts, pesticides, herbicides, and trace metals like selenium, arsenic, and mercury that caused severe deformites in waterfowl in the surrounding wildlife refuges and private wetlands (duck clubs). In 1988, more than 1 million cubic yards of clean topsoil were hauled to Kesterson to bury contaminated sediments.
The US Bureau of Reclamation, owner of Kesterson Reservoir, has been monitoring the effects of residual selenium in sediments, vegetation, groundwater, small mammals, invertebrates, and waterfowl. Biological reports were published through 2001; new data are being collected in 2006.
Kesterson Reservoir is now an upland grassland area. It is off limits to the public and hunting is not allowed there. The National Weather Service and the California Department of Water Resources operate weather stations there.
Since the closure of Kesterson in 1986, there have been many dramatic changes to irrigated agriculture in California and the western US:
1) farmers in Westlands WD were no longer allowed to drain outside the district boundary, forcing abandonment of large tracts of farmland and increased water use efficiency on the remainder;
2) the commitment of a firm supply of clean water to local wildlife refuges under the Central Valley Project Improvement Act of 1992;
3) research into selenium toxicity, bioaccumulation, and occurrence;
4) identification of other sources of selenium contamination around the world from mining, agriculture, petroleum refining, industry, etc.
The San Luis Drain is located along the eastern edge of Kesterson. The Drain is currently used to by the Grassland Bypass Project (GBP) to convey drain water from the 97,000 acre Grassland Drainage Area to Mud Slough, a tributary of the San Joaquin River.