"Warning that salmon and other fish species are in danger of extinction, a federal agency Thursday issued directives that will guide the way dams, pumps, canals and other waterworks in California operate to help ease pressure on the Pacific coast's collapsing salmon fishery.

The biological opinion from the National Marine Fisheries Service affects waterways from the American River to the San Joaquin and will reduce water deliveries to farmers and urban users by about 5% to 7% annually, according to officials. Complying with the court-ordered prescriptions could cost 'hundreds of millions' and would be passed on to water users, according to a federal water manager.

The 800-page document is the latest in a series of actions to address the increasing obstacles to the salmon's twice-yearly runs: upstream migration for spawning, when the fish require cool, abundant water, and downstream emergence of juveniles, which must negotiate the San Joaquin-Sacramento River Delta's maze of gates, canals and diversions to reach the sea."

Julie Cart reports for the Los Angeles Times June 5, 2009. [2]