By 1977, 50 million acres of land in 17 western states were irrigated. The most common irrigation practices are flood irrigation or sprinkler irrigation. The water collected in irrigation projects by above ground ditches or underground tiles discharged to holding ponds, surface water bodies or steams, evaporation ponds or fallow fields. The high rates of evaporation in the west led to increase concentration of toxic elements such as selenium, resulting in adverse impacts to birds particularly deformities. Selenium is an essential dietary element in humans and wildlife but in elevated concentrations causes selenium toxicosis. For additional information on selenium toxicosis we recommend visiting the following web site, http://www.equinevetnet.com/nutrition/toxicosis/ As a result of waterfowl deaths at Kesterson National Wildlife Refuge (now called San Luis National Wildlife Refuge) in 1982, the Department of the Interior initiated investigations at 40 irrigation studies. The studies indicated that 48 percent of Fish and Wildlife Service refuges had problems associated with drainwater constituents. Most of the areas provide habitat for at least one federally threatened or endangered species. The results from the studies have been used to drive efforts to improve the quality of fish and wildlife habitat through acquisition of water rights to retire land high in selenium salts, removal of evaporation ponds and creation of alternative habitat. Problems associated with irrigation drainage still exist in the Tulare Lake bed Area of the San Joaquin Valley, the Salton Sea, and at other sites in the West. Addition information on the National Irrigation Water Quality Program can be found at the following web site, http://www.usbr.gov/niwqp/