USGS Energy Program-Environmental Studies

In the early 1980's, waterfowl at the Kesterson National Wildlife Refuge (KNWR) in the San Joaquin Valley of California indicated that something had gone terribly awry in the environment. In the photo at right, S-313 is a normal embryo, but others are grotesquely deformed, lacking eyes (S-302) or feet (S-35) or other deformities (S-9).

Testing of source waters showed that selenium was present in extremely high concentrations such that the wastewater at KNWR was classified as toxic waste. Underground drainage from agricultural irrigation systems promoted the excessive concentration of this hazardous trace element (from Presser and Ohlendorf, 1987).

image of a normal, upper left, and deformed birds from the kesterson national wildlife refuge in california's central valley

"What happened at Kesterson NWR provides one more illustration of the long-known fact that irrigation projects without adequate outlets for drainage create unacceptable levels of salinity. The unexpected part of the scenario was that, given the right soils and geology, the process of drainage on irrigated lands can also concentrate trace elements to levels that can cause real harm to the biota."

National Research Council
Irrigation-Induced Water Quality Problems, 1989

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http://geology.wr.usgs.gov/wreg/env/birds.html
Contact: Margaret A. Keller (mkeller@usgs.gov)
Western Region Energy Group–Environmental Studies
Modified: November 12, 2002

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