Shutting off the water pumps to save delta smelt unwarranted

This opinion piece originally appeared in the San Francisco Chronicle:

There's great cause for concern over the biological opinion issued by the U.S. Fish and Wildlife Service in the form of a new rules to protect the delta smelt, a fish species that is listed as threatened under the federal Endangered Species Act. That's because millions of Californians depend upon the continued operation of two large irrigation projects for a reliable supply of water. And the scientific reasons for shutting them down to protect the smelt are dubious at best. Myriad factors negatively affect the well-being of the delta smelt. These include, but are not limited to, a low food supply, presence of predatory fish and a toxic water habitat for the smelt. The pumps play a role through entrainment, meaning that smelt can sometimes get sucked into the pumps. But the significance of this and how it affects the species is unknown. No one knows how many smelt are in the delta. Moreover, no study has shown a definitive link between the pumps and smelt viability. As a federal judge overseeing litigation concerning the delta smelt has noted, there is no one cause for the smelt's decline.