Guest commentary by Geoff Vanden Heuvel, Director of Regulatory and Economic Affairs, Milk Producers Council:

I remember being surprised when attending a local Groundwater Sustainability Agency meeting and I first saw a schematic that visually depicted the various levels of groundwater underneath one of the Central Valley’s numerous subbasins. There was a horizontal line going across the chart that said “base of freshwater”.  Beneath the freshwater line there was another line labeled “top of basement”.  I asked the subbasin hydrologist about what occupied the space between those lines and he explained that it was ancient salt water that occupied the lowest depths of the aquifer.  He said a study done decades ago had identified that the salt water was there, but they were now guessing about exactly where, because other than that one study done many years ago, no one had a reason to drill down into it to attempt to characterize it.  Why does this matter? If you are going to estimate how much fresh water is contained in a groundwater basin, you need to know how deep it is.

This story is just one example of what has been going on in the Central Valley over the past few years since the adoption of the Sustainable Groundwater Management Act (SGMA) by California in 2014. This law made actually understanding and managing our underground water aquifers a matter of necessity.  Unlike surface water which can be observed, groundwater cannot be directly measured.  It is present in various geological formations often separated by clay layers of various thicknesses.  Professionals use hydrologic models that extrapolate the location and characteristics of the water layers by using data from wells that have been drilled through them.  The passage of SGMA kicked off a coordinated effort to gather tens of thousands, if not millions of points of data from wells and water sources that have been developed over the decades in each specific part of the Central Valley.  Using what data they could gather, the models create a picture of the current condition of the groundwater basins.  However, given the quality of the data, much of it gathered from inconsistent and old sources, most hydrogeologists admit that their confidence level in the precision of their model results is probably not much better than plus or minus 25%.   But far from being an indication of failure, the rapid and exponential expansion of knowledge, albeit imperfect, brought about by SGMA requirements is a real accomplishment.

It is important to put SGMA in its historical context.  Agriculture in the Central Valley was developed over the past 150 years.  At no time during its development was the pumping of groundwater regulated.  People could drill a well and start pumping anytime they wanted and for most there was groundwater to be found.  Thousands of acres were developed into productive farmland using only groundwater and these farmers did nothing illegal or wrong.  When surface water projects were built, in many cases they were primarily built for flood control purposes.  There were water supply components to these projects, but the water supply features were sized to meet the demand of people who were willing to pay for them. The water supply components of these projects could have been bigger but there was a lack of demand for surface water that was more costly than simply pumping groundwater for free.  The passage of SGMA correctly turns this entire paradigm on its head.  But we need to recognize that it will take time and a significant investment in new infrastructure for the Central Valley to adjust to the new reality. 

Over the past two years it has been my job to follow the implementation of SGMA at the local level.  What I see is tremendous progress, given where we started.  From nothing, there is now something.  SGMA required every part of California that lays over groundwater to become part of a Groundwater Sustainability Agency.  There were skeptics who thought it would never happen.  It did.  Then there was a mandate for the Critically Overdrafted Basin’s to submit Groundwater Sustainability Plans by January 31, 2020.  With one minor exception they all have.  Are the plans perfect or even complete? Of course not.  But every plan identifies the problems and outlines potential solutions.  They all develop water budgets and hydrologic conceptual models.  They all define the data gaps and identify where increased knowledge must be obtained. Those areas that are critically short of water have identified infrastructure improvements to facilitate the expansion of surface water delivery capability, as well as fallowing plans if the needed new surface water fails to materialize.   In short these plans are a very solid first step on a long road to sustainability. 

The GSA’s are mostly young organizations that in many cases for the first time are governing water usage in parts of the Central Valley that have never been organized nor had their water governed. These folks had to find managers and engineers, lawyers and board members.  Then they had to gather mountains of information and make critical community decisions about what their sustainability goals were and how they were going to get there.  A lot has been accomplished. The public should be encouraged by the progress and the GSA’s should be supported strongly because we will all benefit from their success.

About the author: Geoffrey Vanden Heuvel started his work with Milk Producers Council as the Director of Regulatory and Economic Affairs after retiring from a 39-year career as a dairy farmer in Southern California.  His specific responsibilities include being the dairy industry’s eyes, ears and advocate as the various Ground Water Sustainability Agencies begin to implement the Groundwater Sustainability Management Act in California.  Geoffrey developed expertise in groundwater management and California water issues through is nearly three decades of experience serving on the boards of the Chino Basin Watermaster, The Chino Basin Water Conservation District as well as the Southern California Water Coalition where he continues to serve on the Executive Committee.

Please note: The views in this guest commentary are those of the author and should not be attributed to Maven’s Notebook.

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