A sprinkler in a field
Bringing the San Joaquin Valley’s water supplies into balance will require making the most of water that is available while reducing demand, water experts say.

Supply, demand key to balancing valley's water needs

Experts say getting the Central Valley through future droughts will require expanding existing water supplies while reducing demand, partly by voluntarily leaving some land idle.

As general manager of a water district that serves about 27,000 agricultural acres in the southern San Joaquin Valley, Eric Averett knows the solutions to the region’s water shortages are fairly straight-forward.

He speaks of two knobs that valley water users can turn. One controls supply, and the other  demand.

In past years, Averett says he figuratively had his hand slapped by his Rosedale-Rio Bravo Water Storage District board whenever he tried to adjust the knob that affected the supply of water to growers. But as droughts, surface water cutbacks and groundwater overdrafts confront districts throughout the Central Valley, all solutions are now on the table.

“Throughout the valley, we’re going to end up turning both knobs in the future,” Averett said during a recent panel discussion on the valley’s water future.

In short, experts believe the only way to bring the valley’s overburdened water supplies into balance will be to increase supply, mainly by making the most of available water, and reduce demand. And part of reducing demand may well be the voluntary fallowing of agricultural land.

“For some of our hardest-hit areas, the idling of agricultural land is going to be a reality,” says Abbey Hart, the agriculture project director for The Nature Conservancy. She adds that growers may see an economic benefit for converting land into wildlife habitat, but the process will have to be well planned. A checkerboard approach to creating habitat won’t work, she says.

“A lot of these species won’t be able to use tiny patches of land,” Hart told about 200 growers and others at the water forum in early May, sponsored by the Almond Board of California.

Grower input urged

The “Navigating the Waters” forum at the DoubleTree Hotel in Modesto featured a wide range of speakers, including representatives of resource agencies and environmental groups such as the Nature Conservancy and Sustainable Conservation. The Almond Board and Sustainable Conservation have teamed in recent years to fund groundwater-recharge research in orchards throughout the Central Valley.

The experts discussed various critical issues facing California agriculture, including how implementation of the 2014 Sustainable Groundwater Management Act will affect water availability in the future. The speakers urged growers to become more involved in local entities’ water decisions.

“It is clearly time to engage,” says David Orth, a principal for the Fresno-based consulting service New Current Water and Land. “Historically, you elected landowners to your local water agency, the water agency board hired a general manager … The district allocated water supply and sent you a bill.”

That was the extent to which growers were involved with their water distributor, he says.

“But that has changed, and it needs to continue to change,” Orth says. “All of these actions are going to shape our future.”

A sense of urgency has existed in the valley since SGMA was passed at the height of the recent historic drought, as growers and regulators realize that the next drought is around the corner. As surface water was entirely shut off in some areas, many farms got by with groundwater. But the National Aeronautics and Space Administration reported in 2015 and again last year that land in the valley is sinking at historic rates. Moreover, rigorous new state controls are being implemented to reduce nitrates and salinity in groundwater.

The valley’s water challenges call for comprehensive solutions, says Taryn Ravazzini, the state Department of Water Resources’ deputy director for special initiatives.

“There’s no one, single method to manage this natural resource,” Ravazzini told growers. “We’re looking to all of you to manage the future of groundwater … It is the department’s goal to help local agencies put together the strongest plan they can.”

Solutions sought

With more severe water shortages looming, the Public Policy Institute of California has assembled a dozen scientists from the University of California and elsewhere to look for long-term solutions. In a preliminary report last year, they suggested four:

Manage groundwater reserves. Groundwater sustainability agencies being formed under SGMA will need “solid water accounting tools to understand how much water is available and how much is being withdrawn,” the scientists wrote. They will also need to incentivize recharge and reductions in pumping, the team advised.

Expand usable supplies. Capturing and storing more local runoff in groundwater basins and reusing water would help curb near-term deficits, while larger infrastructure investments such as better conveyance of water from the Sacramento-San Joaquin River Delta could help in the long term, the experts wrote.

Reduce demand. Although farmers can save some water through crop choice and management, idling some farmland is also likely in basins that can’t close the groundwater deficit with new supplies. Water trading – both within and across basins – can lessen the costs of shortages, the scientists added.

Explore “multi-benefit strategies.” Groundwater recharge could be managed in ways that improve water supply and quality, the scientists advised. For example, growers could tailor irrigation systems and crop choices to maximize clean recharge in prime areas, they wrote. With the right incentives in place, idled lands could be managed to reduce effects on air quality, while improving wildlife habitat.

“Reducing demand may be scary, but you already do it a lot,” PPIC director Ellen Hanak told growers at the water forum.

The scientists note that for some growers, rotational fallowing may be more economically attractive than permanent land retirement. A system of idling segments of land a season at a time – usually with a cover crop – has been used by some farmers for decades as a way to boost soil health. Recent studies have shown the practice can improve soil moisture infiltration and retention and help with long-term productivity, the scientists’ report noted.

More crop per drop

For high-value crops such as almonds that are known to use more water than some other crops, the push is underway to get “more crop per drop,” as Almond Board officials put it. They note that in the last 20 years, growers have reduced the amount of water it takes to grow a pound of almonds by 33 percent.

In December, the board launched a new initiative to develop new uses for co-products, such as hulls and shells. These co-products have historically been used as livestock bedding and dairy feed, but future uses could include strengthening recycled plastics and feeding hull and shell material to black soldier flies and converting their larvae into a high-protein poultry feed, explains Richard Waycott, the board’s president and CEO.

“Seventy percent of what comes out of the orchard is not the almond kernel,” Waycott says. “We’re producing more hulls every year, and the traditional market for that is not expanding. That’s not a good place for us to be.”

As water becomes more scarce, the co-products could be key to making almond farms more valuable, he says.

“We’re an industry that, in my opinion, belongs here,” Waycott says, adding that board members understand that water efficiency is more important than ever. “The almond board really accepts the responsibility of being the state’s leading crop.”

 

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