What started out to his neighbors as a crazy idea is gaining traction as a good plan.

“It’s not going to solve everything but it’ll certainly help,” said western Fresno Count, Calif. grower Don Cameron.

Cameron’s plan to set aside thousands of acres of farmland for groundwater recharge didn’t start out with much support or praise from others, but as drought lingers and organizations like the Almond Board of California (ABC) talk up the concept of using orchards and other farmland for groundwater recharge, the idea doesn’t seem so far-fetched anymore.

Discussions and a media event at the annual Almond Conference in Sacramento, Calif. in early December promoted the idea of using almond orchards throughout the state to recharge aquifers by applying flood flows during rain and heavy runoff. With over one million acres of almonds from Red Bluff to Bakersfield, proponents suspect there ought to be opportunity for recharge in at least some basins.

Cameron’s grant-funded efforts are still in the paperwork stage though he remains hopeful that dirt will be moved sometime in 2016. The goal is to remove 1,000 acre feet of water per day in flood flows from the Kings River by spreading it across Cameron’s Terra Nova Farms, a diversified operation in western Fresno County.

The win-win will be at least two-fold. First, alleviating flooding on the Kings River can help prevent damage to homes in the area from flooding. The long-term benefit will be seen in groundwater recharge, which is the stated goal of the California Legislature through the Sustainable Groundwater Management Act of 2015.

The Almond Board is not merely talking up the use of flood flows in almond orchards to help recharge depleted aquifers; it’s putting significant money towards the idea.

ABC President Richard Waycott says the marketing order will dedicate part of the $4 million in research dollars it budgeted this year to study how much water orchards can take to achieve groundwater recharge without causing damage to the trees.

The Almond Board is working with the University of California and is partnering with Sustainable Conservation to study the issue.

Sustainable Conservation

Sustainable Conservation is a non-profit organization that works to bring diverse groups together on California’s tough environmental issues, according to Daniel Mountjoy, director of resource stewardship for the organization.

Mountjoy and others spoke to a standing-room-only audience at the almond conference about groundwater recharge efforts and the need for them.

“This is not a new trend,” he said of the state’s declining groundwater.

The drought, coupled with the curtailment of surface water deliveries to growers, forced growers into a situation of groundwater overdraft, which Mountjoy and others at the conference defended as “appropriate” during drought conditions.

The idea is that once drought conditions subside, significant efforts must be made to replenish aquifers to achieve long-term sustainability, Mountjoy says.

Another issue that must be addressed in California’s long-term water management strategy is the use of drip and micro-irrigation systems, which Mountjoy says have presented a series of “unintended consequences.”

“We’ve exacerbated our groundwater situation through our irrigation efficiencies,” he said. “We are no longer flooding and providing excess water that can be returned to the groundwater. Although technologies like this are ideal for drought years it actually has a negative consequence when there is (surface) water and we’re not actually pulling it off the rivers and putting it back into the ground.”

Another factor Mountjoy points to in limiting groundwater recharge has been the construction of levees for flood protection. While he doesn’t suggest removing levees and allowing free-flow flooding to damage private property, perhaps there are methods that can be employed to allow more controlled flows beyond levees and onto land suitable for groundwater recharge.

One idea being looked at by Sustainable Conservation and others is the flooding of farmland in the counties of Stanislaus, Merced, and Fresno. ABC President Richard Waycott says the almond board and Sustainable Conservation will partner with willing landowners and irrigation districts in the counties to recharge groundwater when flood flows become available.

Research perspective

Anecdotal evidence suggests both good and bad outcomes from applying too much water to almonds, according to Helen Dahlke, a hydrologist and assistant professor at UC Davis.

Dahlke pointed out that tree loss has been seen in El Niño years, but questions whether the orchards affected were on suitable or poorly-drained soils. She says other anecdotal evidence suggests benefits related to salt leaching. In short, the research jury is still out.

The Almond Board is also working with Land IQ, a private firm with offices in Sacramento and Los Angeles to map hydrologic regions in the state and determine which soils, and specifically which almond orchards and farmlands in the state, are most suitable for groundwater recharge.

Land IQ specializes in providing solutions to challenging agricultural and environmental problems throughout the world.

Joel Kimmelshue, an owner in and the principal soil and agricultural scientist for Land IQ, says the state’s Soil Agricultural Groundwater Banking Index (SAGBI) has identified 3.6 million acres statewide with a good potential for groundwater banking. SAGBI is a suitability index for groundwater recharge on agricultural land.

But, there’s a catch, he says. The index does not account for subsurface factors.

“If you already have groundwater at 10 or 12 feet, even with an excellent SAGBI score, this needs to be taken into consideration because there’s not a lot of room left for groundwater storage,” Kimmelshue said.

That is why Land IQ will dig deeper into the subsurface factors in its scientific modeling. This includes looking at California Department of Water Resources groundwater levels as it seeks to find suitable locations for groundwater recharge.

Fortunately, data are available from various sources, Kimmelshue says. He showed a series of maps with color layers to illustrate where suitable areas for groundwater recharge might be in the Central Valley.

Total almond acreage figures that could be used for groundwater recharge have not been released, but there are nearly 435,000 acres of almonds planted in the three counties mentioned and about one million acres of almonds statewide. It is not known how much of that land is suitable for groundwater recharge.

Response

Waycott is optimistic that there is a sufficient amount of suitable land for recharge to make a difference. He indicates that some growers have already had success with recharge from their orchards.

“I’m excited about the potential of this project,” he said.

Ashley Boren, executive director of Sustainable Conservation, is likewise optimistic.

“Leveraging almond acreage for groundwater recharge has the potential to benefit the entire Central Valley,” said Boren in a prepared statement. “Once a farmer utilizes his or her land to return water to the aquifer, it serves the greater community, not just the farmer.”

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