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NASA Report Reveals California Is Drawing Too Much Out of Its Groundwater Account

Barry Nelson

Posted December 18, 2009

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A new report from NASA reveals that the Central Valley has lost enormous amounts of groundwater over the past six years. Taken together, the Sacramento and San Joaquin drainages have lost more than 30 cubic kilometers of water since 2003--enough to fill Lake Powell, the second largest reservoir in the country.

These stark numbers reveal how severe California’s groundwater overdraft problem is.

What happened to all of the water? Most of it was pumped out and used for irrigation. But because this groundwater has been drained out faster than Mother Nature can replenish it, wells are starting to run dry.

Think of some Central Valley irrigators as the guy who writes too many checks on the family bank account. After a string of bad checks, the bank simply shuts the account down, and the rest of the family members are left in the lurch. In the case of groundwater, the overdraft is depleting one of the most precious resources we have in our semi-arid state. California has hit peak water. We have run out of rivers to tap and dams to build. With a finite water supply, we can’t afford to squander groundwater too. 

That’s why, as in all Western water conflicts, people are quick to assign blame.  Some say the drought caused the overdraft. It’s true that three dry years have exacerbated the problem, but the NASA data goes back six years. Some say that the problem is caused by Endangered Species Act rulings that cover salmon, steelhead, sturgeon, and smelt, but those opinions were only released within the last year. They are not responsible for this trend. 

No, groundwater overdraft is a problem with deep historical roots. Indeed, California has been here before, and each time we have arrived here for the same reason: the near absence of groundwater regulations in much of California. It’s time we learned from our mistakes and tried a new approach.

We Have Been Here Before

The new, satellite-based NASA data illustrates a problem that began with a simpler form of technology: the centrifugal water pump. The first such electrical pump was installed in California in 1907. Within two decades, overdraft was a recognized problem across California.

These new pumps were so successful that by the time the Central Valley Project was created, one of its aims was to deal with groundwater overdraft. The CVP brought more water into the valley, but it also prompted farmers to bring more land into production, and groundwater was still pumped to make up the difference.

Again, the State Water Project was touted as a solution to the overdraft problem. And yet again, more water was hauled in, more land was brought into production, and groundwater pumping continued apace.

Now we are facing the limits of groundwater once more. And as in the past, some agricultural interests are hoping that state or federal taxpayers will bail them out by building new dam projects – projects that they could not hope to pay for themselves.

But instead of hanging our hopes on costly new infrastructure, it would be more effective, affordable and more equitable for Californians to simply put some rules on the books.

Time to End the Groundwater Free-for-All

No one regulates groundwater pumping across most of the Central Valley. Landowners can pump as much water as they want from their well--or dozen wells for that matter; there’s no limit.

In the American West, California and Texas are alone in not having groundwater regulations. Conservative states such as Arizona and Nebraska have long recognized the need to regulate this resource, to prevent a classic tragedy of the commons.  

This lack of rules seems premised on the assumption that groundwater is not connected to surface waters, and that groundwater is essentially infinite.  Both of these assumptions, of course, are wrong.  Excessive groundwater pumping can drain our rivers and dry up wetlands.  And the NASA report underscores that this is a very finite resource. 

It’s true that much of Southern California has groundwater rules, and some groundwater banking rules apply in the Central Valley, but for the vast majority of the vast Central Valley, it is a free-for-all, where a Wild West mentality still prevails. If you see your neighbor pumping as much water as they please, you want to get your share before it’s gone.

And indeed, if current practices continue, it will be gone someday. When people pump more water than is naturally recharged, we call it groundwater mining. At this point groundwater becomes a non-renewable resource, and eventually wells run dry or it becomes too expensive to pump from dramatically lower groundwater tables. 

Groundwater in California has for too long been out of sight and out of mind.   But at some point, the current groundwater bubble will pop – with the predictable impacts that come with the collapse of unsustainable bubbles in other areas of our economy. 

A New Approach to Groundwater

California has two options when it comes to groundwater. The first is to continue on the current course until we run out of groundwater and the agricultural community must rapidly adjust to jarring changes.  The second option presents a much smoother path into the future – the development and implementation of a groundwater program that manages this resource for the long-term.

Such a program could include limits on long-term overdraft, efficiency measures, realistic water pricing, water transfers from water-rich farmers, transitions to higher value crops, retirement of drainage-impaired lands, reducing ongoing contamination, and investments in alternative economic tools, like solar energy, that can generate jobs and profits while using less water.  In urban areas, capturing urban stormwater and storing recycled wastewater can also help us manage our groundwater more sustainably.

The new package of water legislation that passed the state legislature last month is the first action in decades nudging the state toward the second course. By creating a state-wide groundwater elevation monitoring program, the law will help create a comprehensive database for this critical resource. This information can help spur action to manage groundwater in a more sustainable way.

It’s time California learned from our checkered groundwater history and embraced the sustainable option. All of us--farmers, homeowners, urban businesses--will benefit.

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Rocky RaccoonDec 20 2009 03:10 PM

You write that California and Texas are the only two western American states that do not regulate groundwater withdrawal. To give a bit more detail, the state of Texas is maneuvering to regulate groundwater. The state has developed stakeholder committees, which will each determine the minimum level below which an aquifer will be not fall. This is similar to the recent efforts to establish bare minimums for instream flows. Further, Texas groundwater conservation districts generally limit (to a small extent, at least) the number of wells per tract, pump capability, etc. (about a hundred GCDs, each with unique powers, cover most of the state's inhabited areas). Also, Texas monitors its aquifers, unlike California. That being said, the battle to regulate groundwater (perceived as private property) in Texas is fierce as you can imagine for what is essentially a libertarian state, politically. The two states should learn from each other.

Philip BowlesDec 21 2009 09:47 AM

The incredibly varied hydrological landscape of our state makes centralized groundwater regulation cumbersome and expensive. What makes sense in Lancaster may make no sense in McArthur. However, agriculture's knee jerk opposition to any reasonable efforts to protect regional aquifers will leave them out in the cold when it comes to designing and implementing a regulatory system.
Fortunately, unlike Texas, a lot of California's groundwater is renewable rather than fossil water. But is is only renewable as long as aquifers are not destroyed by subsidence or pollution.

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