Stanford University released a study this week stating that California has three times more useable groundwater located in deep aquifers than previously estimated. This might come as welcome news to a state that continues to suffer through a historic drought. The researchers found that fresh groundwater was available at depths previously thought to be too deep to contain fresh water.
At the outset, readers should note that “freshwater” and “drinking water” are terms of art having regulatory and legal distinctions, and ultimately making a difference for the public welfare. The definition of freshwater varies depending on the state or federal agency; however, freshwater is generally defined as having less than 3,000 mg/L of total dissolved solids (“TDS”). Underground Sources of Drinking Water (“USDW” or “drinking water”) as defined by the Environmental Protection Agency include groundwater aquifers with less than 10,000 mg/L TDS. For reference, seawater contains approximately 35,000 mg/L TDS.
Historically, California’s fresh groundwater supply was thought to be limited to water found above 1,000 feet. However, the researchers determined that the mean base of fresh water (“BFW”) in five Central Valley counties (Kern, Fresno, Solano, Colusa, and Yolo) ranged from 1,345 feet (Colusa) to 2,204 feet (Kern). The base of drinking water is considerably deeper than the freshwater. Specifically, USDW can be found in Kern and Los Angeles Counties at depths deeper than 8,200 feet.
Continue Reading Does California Bear A Water “Windfall” From Deep-Aquifer Sources?