In 1993, the U.S. Fish and Wildlife Service listed the delta smelt, a two- to three-inch fish that has little, if any commercial value, as threatened under the Endangered Species Act (ESA), and in 1994 designated, as critical habitat, a large area of the Sacramento-San Joaquin Delta in central California, which is the source of water supplied by the Central Valley Project and the State Water Project. The area supplies more than half of America’s nation’s fruits, vegetables, and nuts.
Under Section 7 of the ESA, federal agencies must ensure that their actions are not likely to jeopardize the continued existence of a listed species or result in the destruction or adverse modification of critical habitat. Thus, the Bureau of Reclamation, which operates the Central Valley Project, was required to seek a biological opinion from the FWS to determine if operation of the water projects would likely jeopardize the listed species or modify its critical habitat.
In 2005, the FWS issued a “biological opinion” that determined the water projects’ operations would not adversely affect the delta smelt or its critical habitat. Environmental groups successfully challenged the opinion and another opinion was issued in 2008, which found that the water projects’ operations would likely jeopardize the continued existence of the delta smelt and adversely modify its critical habitat. The FWS proposed “reasonable and prudent alternatives” that the Bureau of Reclamation could undertake, all of which involved decreasing to a devastating degree the water available for domestic and agricultural uses, as well as for storage.
In 2010, a California federal district court struck down the biological opinion; however, in March 2014, a panel of the Ninth Circuit reversed. The petition for writ of certiorari was filed on September 30, 2014.