The Trump administration has announced a plan to divert water to California farmers, fulfilling a campaign promise by the president, but contradicting federal biologists who found the plan would drive endangered salmon closer to extinction and could harm other fish.

Allocating water is always a fraught issue in a state plagued by drought, and there's a lot at stake: irrigation for millions of acres of farmland in the country's biggest agricultural economy, drinking water for two-thirds of Californians from Silicon Valley to San Diego, and the fate of threatened wildlife.

An analysis completed by NOAA Fisheries biologists in July found the administration's proposed plan jeopardized the future of endangered fish. Under federal law, they are then required to impose limits, such as restricting how much water can be pumped to farms from the state's rivers.

Instead, the administration removed those biologists from the project and brought in other staff to rewrite their decision.

"We've been able to create a much smarter approach that focuses on real-time management," says Paul Souza, U.S. Fish and Wildlife Service Pacific Southwest regional director. "Our commitment is that we will be as, or more protective than we have been in the last 10 years."

The water pumping rules are integral to the majority of California, since they govern a crucial water source: the Sacramento-San Joaquin Delta.

The water is also crucial to the survival of endangered salmon and threatened delta smelt, whose numbers have plummeted. Chinook salmon have lost as much as 90 percent of their historic river spawning grounds due to dam construction.

As their numbers have gone down, so have endangered killer whales in the Pacific, which feed on the salmon while the fish are at sea.

The administration's latest plan creates new hatcheries to breed fish, and relies on real-time monitoring to track the location of threatened fish. They plan to slow pumping when the fish are nearby.

Still, environmental and fishing groups say the decision is scientifically unsound and shows political interference.

Prior to becoming secretary of the Interior Department, an agency overseeing this process, David Bernhardt was a lobbyist for Westlands Water District, a major agricultural district in the Central Valley.

"The servile Interior Department has hijacked and subverted the scientific process," said Noah Oppenheim, executive director of the Pacific Coast Federation of Fishermen's Associations, in a statement. "Fishing jobs are being sacrificed to benefit the corporate agriculture lobby, pure and simple.

What are these water rules?

The rules, known as "biological opinions," generally have put environmental safeguards on the vast network of dams and pumping plants in California. At least two-thirds of residents use water from this system, which goes through California's delta. But diverting that drinking water has also meant dramatically reducing freshwater in the delta's ecosystem.

Since salmon are born in rivers and migrate through the delta to reach the ocean, the federal rules have generally done two things to protect them. First, they slow the speed of the massive pumps in the south delta to keep fish from being drawn into them. Second, they ensure salmon eggs in the Sacramento River aren't killed by hot temperatures. That requires conserving water behind Shasta Dam so it can be released in the summer to keep the river cool.

Central Valley politicians and agricultural interests have long fought these rules, which reduce their water supply in some years.

When the Bureau of Reclamation, which delivers water to the Central Valley, proposed pumping more water from the delta, it then fell to federal wildlife agencies to review that decision and write up what are called biological opinions. The agencies must put limits on the water pumping if they find the rules would harm endangered species.

Fast-tracking the rules

In October 2018, President Trump ordered that the water rules be written faster than ever before.

"We will have it done very, very quickly," Trump said to members of the California GOP congressional delegation last October, as he signed an executive order. "I hope you enjoy the water that you're going to have."

According to emails obtained last winter by KQED, NOAA Fisheries scientists were concerned they didn't have the resources to analyze the plan.

In July, those scientists found that the increased water pumping would "jeopardize" the existence of salmon and other species. Before that document was released, the Trump Administration brought in a new team of federal attorneys and decision makers to work on the rules, removing the biologists who had previously worked on it.

In its final plan, the Trump administration finds the increased water pumping would not jeopardize the existence of salmon or delta smelt.

What would the administration's plan do?

The Trump administration says it plans to run its water pumping operations based on real-time monitoring of fish populations, slowing pumping to avoid harming them when they're near water infrastructure. Because of that, it wouldn't say exactly how much water will reach farmers in the Central Valley.

"It'll be some time before we operate in this new plan and be in a position to actually determine definitively whether and to what extent the new plan actually increases water supply," said Ernest Conant, regional director for the Bureau of Reclamation. "It could very well, in certain years, decrease it."

Environmental groups are not convinced by promises to monitor the fish, because they say it's difficult to track them when so few are left.

"These new biological opinions weaken virtually every protection required by previous decisions, eliminating clear, science-based habitat protections," said Kim Delfino, California program director for Defenders of Wildlife.

The administration says it will also share the cost for $1.5 billion in restoration and habitat projects. It plans to support a hatchery to breed delta smelt, a species on the brink of extinction, and restore creeks vital to salmon.

What's next?

The new rules could go into effect early next year, affecting the water deliveries for cities and farms during the spring and summer. But fishing and environmental groups are likely to sue, alleging that the rules don't go far enough to avoid extinction of endangered species.

Depending on what a judge decides, the new plan could be tied up in court for years.

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