A federal appeals court on Monday upheld a 2009 federal decision that called for reducing the amount of water pumped from the Sacramento-San Joaquin Delta in order to protect salmon and other species.
The 2009 environmental review by the National Marine Fisheries Service found that continuing to pump water from the delta at such a high rate would threaten several endangered salmon species and killer whales.
Some of the state's biggest water agencies, including Southern California's Metropolitan Water District, had challenged the 2009 federal decision. A lower court had invalidated part of the National Marine Fisheries Service's review but allowed the reduced pumping to remain in effect.
The 9th U.S. Circuit Court of Appeals on Monday affirmed the original 2009 federal decision reducing the pumping.
Federal fisheries officials, representatives of the state fishing industry and environmental groups welcomed the news.
"Today's federal court of appeals ruling upholds protections for salmon, steelhead trout, killer whales and other wildlife that rely on natural river flows in California's Central Valley and a functioning delta to survive," said John McManus, executive director for the fishing industry's Golden Gate Salmon Association.
Federal biologists in 2009 said water withdrawals from the delta were driving endangered killer whales off California closer to extinction by reducing salmon and other fish the killer whales depend on for food.
Daniel O'Hanlon, a lawyer for the water districts, did not immediately return a request for comment.