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Here's an unexpected answer for the groundwater shortage

Facing El Nino, California may face both a drought emergency and flood emergency at the same time.

El Niño is expected to be "Godzilla" strength this year, bringing record-setting precipitation to California’s parched landscape.

Congressional representatives in October sent a letter to Gov. Jerry Brown asking about his plans to ensure that when El Niño’s storms hit, the water is captured. 

This is a smart question — but part of the answer is not what these elected officials likely would anticipate. More dams, greater surface storage and looser environmental permitting do not add up to a sustainable water supply for California. We need to think outside of the box.

In an average year, groundwater meets about 40 percent of the state’s water demand. In a drought, it meets more than 60 percent of the demand.The state’s increasing reliance on groundwater, especially during drought years, has created serious problems, such as reduced groundwater in storage.

At the same time, California’s farmers are wrestling with hundreds of thousands of acres of fallowed fields and declining profit margins due to water scarcity.  

The California Water Foundation released a report recently showing the potential to significantly improve groundwater levels in San Joaquin Valley by directing excess river flows from winter storms to active farmland. 

By flooding fields when the rains do come, we can help slow declining groundwater levels.

The conservative findings show that groundwater overdraft in San Joaquin Valley’s eastside could be cost-effectively reduced by 12 to 20 percent each year. In other words, by flooding fields when the rains do come, we can help slow declining groundwater levels. 

The report makes clear that outreach will be needed to get farmers to participate in these projects — and economic incentives likely will be needed, too.

But at the end of the day, if growers come on-board using farmland and existing infrastructure to divert and convey the water, it will make these projects very cost-effective.

While it is counterintuitive to think that California may be in a state of drought emergency and flood emergency at the same time, this is becoming a looming reality. Climate change likely will proliferate such events with more frequent periods of drought and high intensity of rains when they do come. 

This paradox gives us the opportunity to think about drought and flooding in the same context. As shown by the study’s findings, tapping the state's farmland for groundwater recharge could be an important piece of the puzzle in reducing water scarcity risks and putting the state’s future water supplies on a more sustainable path.

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