Saying current water conditions pose particular peril for the state's tiny, disappearing Delta smelt, federal officials moved to temporarily reduce water deliveries for farmers and millions of other Californians.
Especially muddy water from winter storms is among the factors that risk sweeping some of the world's few remaining Delta smelt off course and into giant water pumps that draw water from the Sacramento-San Joaquin river deltas, U.S. Fish and Wildlife officials said.
The pumps are part of federal and state water projects that provide water for up to 25 million Californians. Wildlife experts believe the pumps are one of the main threats to native fish, including the once-plentiful Delta smelt, now nearly extinct, and endangered runs of native salmon.
The federal wildlife service's determination on Thursday means federal authorities will reduce water flows temporarily starting Friday, the U.S. Bureau of Reclamation said.
Water deliveries to farms, water agencies and other customers from the Delta are an intensely political topic in California, with water users often at odds with environmental groups.
Farming representatives said the move is troubling, coming after a series of storms that have brought a surge in both rains and optimism about the drought.
"It's obviously very, very concerning at a time when we're supposed to be capturing water," said Ryan Jacobsen, executive director of the Fresno County Farm Bureau.
The throttling back of water deliveries is coming during California's winter rains, when water managers and users hope to capture as much water as possible to fill reservoirs in the state, which is in its fourth year of drought.
Asked earlier Thursday if he was concerned about Delta smelt being chewed up by the giant pumps in the push to fill reservoirs, California Gov. Jerry Brown said, "That's why they will have to be managed very carefully, and there won't be as much water."
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