
Last week, President Trump’s Department of the Interior decided to exempt itself and the California State Water Project from rules protecting threatened native fish and their critical habitat in the Bay-Delta estuary. These rules are called “Fall X2,” and they require maintaining freshwater habitat in the Delta further west in wet years like 2017, when water is abundant. Right now, a request is pending with the State of California to join with Trump in weakening these rules. In 2011, the California Department of Fish and Wildlife (DFW) concluded that, “The Fall X2 action is expected to be fully implemented in future years. The continued implementation of the Fall X2 action in future years when applicable is integral to [DFW's] ability to find consistency” of the big water projects’ operations in the Bay-Delta under California’s Endangered Species Act. The State is going to decide very soon whether it stands with Trump, or stands with science.
Yes, 2017 was the wettest year ever recorded in northern California, so you’d think there would be plenty of water to go around. And, yes, the abundance of delta smelt, chinook salmon and other native fish is hovering around the lowest levels ever measured. And, of course, regulators took over 1.3 million acre-feet of water away from fish protections during the drought to give it to the water agencies that contract for water from the massive Central Valley Project (CVP) and State Water Projects (SWP), contributing significantly to the dire condition of threatened and endangered Bay-Delta fish today. But… the big water contractors and the wealthy interests they serve—including the Metropolitan Water District of Southern California, Kern County Water Agency, the Wonderful Company, and Westlands Water District—just weren’t satisfied with receiving the highest CVP/SWP water contract allocations since 2006, and wanted more cheap water. So the Trump Administration gave them more, by weakening scientifically-justified fall outflow requirements for native fish that are perched on the knife’s edge of extinction. The Trump Administration had no valid scientific basis for doing so, and their action is clearly unlawful.
The fisheries protection that the U.S. Bureau of Reclamation (Reclamation) sought to weaken—and the U.S. Fish and Wildlife Service (FWS) agreed to weaken—is the Fall X2 requirement from the 2008 delta smelt biological opinion. Fall X2 is designed to provide improved habitat for delta smelt in the fall of wetter years by pushing X2—the area where salinity in the estuary measures 2 parts per thousand and where delta smelt like to congregate—farther towards the ocean, to allow fish to access the better, open-water habitat of Suisun and Grizzly Bays. The way it works is graphically illustrated below, in the materials sent to FWS by Reclamation:
The blue areas depict the habitat available to delta smelt when X2 is centered around 74 kilometers from the Golden Gate, which is the requirement of the 2008 biological opinion in wet years like 2017. Smelt can access the wide-open spaces of Grizzly, Honker and Suisun Bays, which provides better habitat, more food, and more habitat than when X2 is upstream.
But this what it looks like when X2 is set at 81 kilometers from San Francisco's Golden Gate Bridge—the location that Reclamation requested in its plea to FWS to waive this year’s requirement. Delta smelt can no longer access the favorable, open-water habitat of the western edge of the Delta, but are crowded into the upstream, channelized areas of the Delta. Reclamation later modified its request to set X2 at 80 kilometers, which similarly constricts the habitat area and quality for delta smelt.

The distinction between these locations of Fall X2 makes a big difference. The one time that the Fall X2 action was implemented previously, in the last wet year of 2011, delta smelt saw their population increase by nearly ten times, and grew bigger and more fecund (i.e., had more babies) than in years when they couldn’t access this habitat. The delta smelt desperately need that kind of boost right now, after their population plummeted during the drought. The most recent spring smelt abundance survey shows their rebound after Fall X2 was set at 74 kilometers in 2011, and their current depleted numbers:

FWS and Reclamation didn’t just ignore the science behind this action. Both agencies also admit that the decision to move X2 farther upstream this year from the 74 kilometers required in the Biological Opinion will adversely affect delta smelt critical habitat. See, for example, page 5 of the Request for Reinitiation. This is not permitted under the federal Endangered Species Act, which prohibits actions that adversely affect critical habitat. The agencies actions are in blatant violation of the law.
FWS claims its decision is limited to the month of October, 2017, but it is clear that this approach of ignoring the science and the law is going to be the new paradigm for Trump Administration management of the Bay-Delta estuary, and we expect many more decisions to weaken or waive the requirements of the delta smelt and salmon biological opinions in the months and years ahead. Fortunately, the State of California can put a stop to this. The California DFW and Department of Water Resources (DWR) have authority under the California Endangered Species Act over how the water projects are operated and how native fish are protected—or not—in the Bay-Delta. Right now, DFW’s exercise of that authority requires that the joint operations of the CVP and SWP meet Fall X2 at 74 kilometers in the month of October.
DFW and DWR can and must resist the Trump Administration’s call to weaken that requirement if we’re going to protect native fish and restore the Bay-Delta.