A first for delta water pumping: Voluntary cutback to protect fish
On New Year’s Eve 2012, the Sierra had 140% of the normal December snowpack and rivers swelled with storm runoff. But strangely, a crippling reduction of water pumping had already begun in Northern California.
The muddy Sacramento River and mammoth water pumps had created a death trap for the protected delta smelt. Under the federal Endangered Species Act, the pumps had to be slowed, even though California was flush with water. Farmers and Southern California lost 800,000 acre-feet of precious water in the process —followed by months of almost no storms.
Scientists explained that the smelt are attracted to the muddied river flows during storms, and the big gulp of 25,000-horsepower pumps dragged muddy water toward the dangerous pump intakes.
Flash forward to this week, and the same scenario was lining up again. State and federal water leaders made a historic decision — slow down the pumps, let some water run to the ocean and protect the fish long before they get near the pumps.
How is that different from 2012? This time, there was no Endangered Species Act restriction. It was a voluntary act in hopes of heading off a problem later.
The loss this time might be less than a tenth of the 800,000 acre-feet in 2012, which left farmers and cityfolk scrambling for alternate sources.
It’s a gamble that might backfire, especially for west San Joaquin Valley agriculture, say farm water officials, who add that they support this temporary cutback.
But if the delta smelt somehow wind up near the big water pumps at the Sacramento-San Joaquin River Delta later on, federal restrictions will slow water exports anyway.
“We give the water projects credit for trying something new, but we still could wind up heavily regulated,” said Ara Azhderian, water policy administrator for the San Luis & Delta-Mendota Water Authority, representing water contractors on 2.1 million acres of farmland. “Then all they’ve really done is add to the water lost.”
It may seem like a subtle change in the perennial fight over river water passing through the declining delta ecosystem where the delta smelt, winter-run chinook salmon and other fish species are protected under the federal Endangered Species Act. But drought duress is forcing changes, say state and federal water leaders.
“It’s an innovation that’s been brewing for a few years,” said Mark Cowin, director of the California Department of Water Resources, which operates the State Water Project. “It’s not easy to bypass any water supplies, but it could save hundreds of thousands of acre-feet of water.”
One of the keys is more real-time tracking of the delta smelt, an elegant, 3-inch fish that smells like cucumber and lives only in the delta. The fish was listed as threatened species in the early 1990s. Its numbers have continued downward.
The water export pumps are a focus of protection for the smelt, but there are other smelt stresses. They include predators such as the striped bass, treated waste water from Sacramento and other cities, drainage carrying pesticides and other toxins from delta-area farming, pollution from storm runoff and declines in food sources.
To protect the smelt from pumping, officials had been relying on monthly trawls at sites all over the delta and the appearance of smelt at the pumping station in the south delta.
But after the 2012 losses, water project leaders decided to amp up monitoring of the smelt earlier this year, even though there were no pump slowdowns needed this year to protect smelt.
“We can make real-time changes to project operations if conditions warrant,” such as this week, said David Murillo, regional director of the U.S. Bureau of Reclamation. The bureau operates California’s largest water system, the Central Valley Project, which is the dominant water project in the central San Joaquin Valley.
The cloudy, muddy water, called turbidity, is another key. It gives delta smelt a place to hide from predators, said spokesman Steve Martarano of the U.S. Fish and Wildlife Service, so the fish tend to be attracted to it.
“There are also food sources in the turbidity,” he said.
A turbidity plume appeared in the delta following a large storm several days ago. Crews trawled the delta and found several delta smelt in an area where they could easily move toward the pumps, according to state and federal agencies.
At the time, the pumps were daily exporting 5,500 acre-feet of water — each acre-foot containing 326,000 gallons or an 18-month supply for an average family. The pumping was cut back to about 3,500 acre-feet per day, even though more storms were on the way.
The pumped river water is sent south to reservoirs serving 25 million California residents and more than 3 million acres of farmland.
After the late 2012 water losses due to pumping cutbacks, California encountered one of the most intense dry times on record. A tense drama and a lot of angst followed. The drought eventually triggered an unprecedented cutback in 2014 for west Valley farmers who have historic rights dating back to the 1800s.
To provide water for those farmers, the bureau tapped Millerton Lake, leaving 15,000 east-Valley farmers with no water for the first time since the project began delivering water decades ago.
Friant Water Authority, representing the 15,000 farmers, supports the Bureau of Reclamation’s decision to slow down pumping in hopes of allowing the exports to continue through the winter, said Ronald Jacobsma, general manager of the authority. He said east-side farmers desperately need the west-siders with longtime water rights to get their supplies next year.
Jacobsma said: “We simply cannot withstand another zero water supply allocation for the Friant Division’s 15,000 family farmers, nor for the thousands of people who have lost or are threatened with losing residential water service this year.”
This story was originally published December 20, 2014 at 2:00 PM with the headline "A first for delta water pumping: Voluntary cutback to protect fish."