Who needs sustainable desalination? We have El Niño!

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Recent news sources and weather reports have warned California residents that the coming El Niño will be the most severe on record since the El Niño of 1997-98. Many of these reports have inspired relief in Californians, with the hope that heavy rainfall across the state this winter will restore California’s water reserves to their pre-drought levels. Forecasters are less sanguine whether even a record rainfall can end the drought:

 “If the wettest year were to occur, we still wouldn’t erase the deficit that’s built up in the last four years.”

– Alan Haynes, National Oceanic and Atmospheric Administration (NOAA)

“The big reservoirs — Oroville, Shasta and the many hundreds of small reservoirs up and down the state, as well as the groundwater basins — it just takes a long time to fill all that stuff up. It’s never happened in one winter.”

– Bill Patzert, NASA’s Jet Propulsion Laboratory

One season of heavy rainfall is not a panacea for all water woes in California. El Niño is a rare climate cycle characterized by warmer-than-average seawater in the tropical Pacific Ocean resulting in warm, wet weather for the US West Coast. While a series of storms will likely bring torrential rainfall to California, we still need to be thinking about conservation and new solutions to help regulate the supply of water in our state as part of a long-term plan for water sustainability.

The amount of rain likely to fall in California is not enough to reverse the effects of the 4-year drought. For one thing, we don’t have adequate storage facilities to capture all of the water falling from the sky. For another, the supply and demand gap for water in California is much higher than what can be produced naturally with one good year of rainfall. The 2015 drought alone resulted in a shortage of about 8.7 million acre-feet of surface water and was offset by 6 million acre-feet of additional groundwater pumping for that year. Groundwater pumping is far from being a sustainable source for Californians as the only way to replenish these reserves is through additional rainfall. The demand gap will only continue to grow if we continue using water, even in wet years, the same way we have been for decades in California.

To put the current water deficit in perspective, the amount of precipitation California’s Sierra Nevada has lost in the four-year drought has been 2.5 to 3 times the average annual precipitation. During the wettest year on record, 1982-83, the Sierra Nevada didn’t quite get double its annual average precipitation.

What the history of drought and storms in California shows is that the climate regularly cycles between hot, dry weather, and occasional wet seasons. With climate change, we can expect extended and more extreme droughts due to the rising temperatures. While the precipitation this season will be helpful, we need to take the temporary relief to prepare for future water-scarce conditions.

Each year since 1962, California has been steadily losing an average of 1.5M acre-feet of water (measured as groundwater storage), regardless of whether or not we are experiencing a drought. This means that even during wet seasons, like the one currently being forecast, we are still depleting the annual stored water supplies for over 1.5M California households (the average household uses 1 acre-foot of water in a year). Groundwater storage is our most precious water resource; it is our water “savings account” and should only be drawn from sustainably with a balanced budget. But the demand for water in California has a habit of outstripping the natural supply, forcing us to overdraft our groundwater supply.

The chart below shows surface water deliveries and cumulative storage changes simulated by the Central Valley Hydrologic Model.


Naturally occurring water supplies have proven to be unreliable for Californians. On the other hand, desalination, and especially solar desalination, would allow farmers and other business owners whose livelihood depends on water to plan for dry years as well as wet ones in order to maximize their revenues. Implementing an onsite desalination project, such as HydroRevolution, also allows farmers to reuse a significant portion of their irrigation water, thus conserving water with a clean alternative.

Moreover, storms in California aren’t going to do anything about the salt accumulation problem especially prevalent on the west side of the Central Valley. Buildup of excess salts and minerals are a natural occurrence following irrigation of cropland, but the salty drainage water this creates is taking up profitable space on land dedicated to drainage rather than crops. Even if we experience enough precipitation in California to significantly alleviate the drought, we still need to adopt conservative practices in certain industries in order to maximize the potential of the land, water, and our energy. HydroRevolution is capable of treating drainage water with zero liquid discharge in order to purify agricultural water and package solid salt co-products for sale to other markets. This technology would provide an economic solution to the fallowing of land that is likely to occur in these regions if no other solution is found for drainage.

Yes, the El Niño storm is a welcome sight to the parched landscape of California, but we need to think about how we can get involved and be a part of the change as well. By joining the HydroRevolution you can help bring a sustainable future to California water.