Delta pumps throttled back despite rains, cutting California water deliveries to protect fish
Joe Del Bosque, like other San Joaquin Valley farmers, had been watching with rising hope the massive amounts of rain and snow that’s fallen in California this winter.
Del Bosque is dependent on water pumped south from the Sacramento-San Joaquin Delta to irrigate his crops on the Valley’s west side in Fresno and Merced counties. These last two years of drought-driven pumping restrictions have forced him to leave fields barren and reduce water available to his valuable almond trees — cutting into his bottom line.
He’d hoped the federal government would crank up its pumps and start sending water his way now that the Delta is flush with storm runoff in what’s so far been a remarkably wet fall and winter in much of Northern California.
Instead, to protect Delta smelt — a nearly extinct fish that’s come to symbolize California’s never-ending fight over water — regulators throttled back the pumps that supply drinking water to 25 million people from Silicon Valley to Orange County and millions of acres of farmland like Del Bosque’s.
On Dec. 20, the state and federal managers of the two arena-sized pumping stations near Tracy substantially reduced pumping for two weeks. The decision was made as part of the complex, scientifically-based formulas that govern how much water can be pumped while protecting fish like the smelt.
“This 14-day pumping reduction is anticipated to reduce movement of endangered fish toward the pumping facilities, thereby reducing impacts to endangered fish and potentially allowing for increased flexibility in pumping operations for the remainder of the winter,” the U.S. Bureau of Reclamation, which manages the federal pumping station, said in an announcement.
Because of the drought, most Valley agricultural districts received zero water allocations in 2021 from the federal government’s Central Valley Project. The State Water Project delivered just a 5% allocation. Now snow is piling up in the Sierra, and Folsom Lake is filling so quickly that dam operators have been releasing water to ward off potential flooding in Sacramento, contributing to higher flows in the Delta.
Had the pumping restrictions not been in place, the Delta plants could have shipped around 250,000 acre-feet of water into San Luis Reservoir, the Merced County storage facility that serves as a sort of holding tank for the state and federal governments’ south-of-Delta water-delivery projects, according to estimates from various agencies dependent on Delta water.
For comparison, 250,000 acre-feet is roughly a quarter of Folsom Lake’s total capacity.
During the two weeks, the amount of water going out to San Francisco Bay instead of being pumped south for the Central Valley Project contractors alone could have irrigated about 34,500 acres of westside farms for a year, said Tom Birmingham, the general manager of the sprawling, Fresno-based Westlands Water District.
Fish in peril
The restrictions come at a critical time for Delta smelt, a species that independent researchers have been warning for years could go extinct in the wild at any time, if they haven’t already.
Over two days this month, state and federal scientists took the unprecedented step of releasing 12,800 hatchery-raised smelt into what’s thought to be their critical spawning habitat near Rio Vista.
The fish, raised in a small UC Davis laboratory on the Delta, were marked by having a small, non-essential fin clipped off their back so that researchers could identify them if they’re netted again.
“As we catch these fish, we want to find out … how well they’re doing in the wild,” said Ken Paglia, a spokesman for the California Department of Fish and Wildlife, which was among the state and federal agencies that collaborated on the project. “And then we want to find out if hatchery-raised smelt will spawn in the wild.”
It’s a last-ditch effort to stave off the extinction of the short-lived, three-inch translucent fish that smell a bit like cucumbers when handled out of the water.
It’s been a remarkable collapse — one that doesn’t bode particularly well for other coldwater fish species that swim in the Delta and the rivers that feed it.
As recently as the 1970s, the Delta smelt numbered in the millions and were among the most numerous fish in the West Coast’s largest estuary, which begins just south of Sacramento.
Now, for the fourth year in a row, state biologists caught zero smelt in their nets during their annual fall surveys.
UC Davis fisheries scientist Peter Moyle, who’s been studying the smelt throughout their decades-long collapse, said he’s not particularly hopeful the hatchery releases will do much good.
“I must admit I’m on the skeptic side,” he said. “I’m glad they’re doing it because it’s truly the one of the only other things left to do … I guess the big question becomes whether the habitat is right for them.”
Problems with no solutions
The plight of the smelt species, which is protected under the U.S. Endangered Species Act, underscores the environmental damage caused by decades of alterations to California’s major waterways to meet human demands.
The Central Valley’s major dams, including Shasta and Folsom, cut off salmon, steelhead and other migratory fish from their coldwater spawning grounds.
As rivers were channelized for shipping, agriculture and flood control, critical floodplain habitat that provided fish food and shelter from predators was lost. Humans also pull a staggering amount of water out of the state’s rivers. For instance, in some years, as much as 80% of the water in the San Joaquin River watershed is captured by a dam or shunted into a canal for use by farms and cities.
In the Delta itself, the meeting point of the Sacramento and San Joaquin rivers — and the distribution point of California’s elaborate north-to-south water system — relentless pumping further reduced fish populations and helped push the smelt to the brink of extinction.
The pumps are so powerful that they can reverse natural water flows, disrupting migratory patterns and driving fish toward predators.
Climate change, meanwhile, is warming rivers. This creates ideal conditions for invasive plants and fish that out-compete native species. Warmer water also contributes to toxic algae blooms fed by pollutants washing down from farms and cities.
In all, it’s little wonder 83% of California’s native fish species are struggling to survive, said Andrew Rypel, another fisheries scientist at UC Davis.
“Just let that register for a sec: 83% of the fish fauna is doing very poorly,” Rypel said. “That’s amazing to me. And it shows kind of the scope of the problems that we’re dealing with.”
A political bottleneck
For Valley farmers, the smelt has come to symbolize what they consider to be unfair environmental restrictions, giving Republican politicians with presidential ambitions easy applause lines.
On the presidential campaign trail in 2016, Texas U.S. Sen. Ted Cruz said smelt go well “with cheese and crackers.” At a Fresno rally the same year, Donald Trump promised to “open up the water” for farmers and mocked “a certain kind of three inch fish.”
Trump’s administration relaxed the environmental restrictions on Delta pumping in an effort to ship more water to San Joaquin Valley farmers. President Joe Biden’s administration is seeking to reverse that, a process that could take years.
In the meantime, state and federal water agencies developed temporary Delta pumping rules that have been denounced by farmers as too stringent and by environmentalists who say the rules are not strict enough.
Rypel said one potential solution that could save Central Valley fish species are long-promised agreements that would see farms and cities voluntarily relinquish water and cough up hundreds of millions of dollars for large-scale habitat restoration projects. The voluntary agreements have effectively collapsed under Gov. Gavin Newsom’s administration, setting the stage for more lawsuits and acrimony as species continue to go extinct.
“There’s always the talk of voluntary settlements or things like that but nothing big has been put together yet,” Rypel said. “And that’s really what I’d like to see happen eventually.”
In the meantime, state and federal water managers and regulators have few options to protect fish other than to force cities and farmers like Del Bosque to take less.
He said he doesn’t have any ill will toward the regulators.
“We get frustrated, but we understand they’re doing the best they can,” Del Bosque said.
He said he just hopes that the rain and snow keep falling and the restrictions will ease so the pumps will start sending water into San Luis Reservoir for California’s inevitable dry season, just a few short months away.
As it stood Thursday, San Luis wasn’t even a third full.
This story was originally published December 30, 2021 at 9:41 AM.