Outlook Out of sight but not out of mind: California refocuses on groundwater Thomas Harter, UC Cooperative Extension Specialist, Department of Land, Air and Water Resources, UC Davis Helen E. Dahlke, Assistant Professor, Department of Land, Air and Water Resources, UC Davis A deepening 3-year drought, accentuated by a record dry 2013, has focused public attention on groundwater like never before. And for a good reason: Almost everywhere in California, groundwater levels have been drawn to record depth and domestic and farm wells are drying up at an unprec- edented pace. Well drillers are booked for months in advance to deepen existing wells or to construct new, much deeper ones. Even in a wet year, groundwater makes up one-third of our urban and agricultural water supply, but in 2014, as in previous dry years, nearly two-thirds of the state’s water supply will be pumped from wells that are tapping into California aquifers. The economic consequences of not having this hidden resource avail- able in future droughts would be catastrophic. Thomas Harter A significant number of regions in California won’t have groundwater available in another generation or two if we continue business as usual. Kings County well pumping into an irrigation system. 54 CALIFORNIA AGRICULTURE • VOLUME 68 , NUMBER 3 Yet, a significant number of regions in the state will not have this resource available in another generation or two if we con- tinue business as usual. As groundwater depletes, damage will increase to our water, transportation and urban infrastructure due to land subsidence; critical ecosystems in groundwater- dependent streams will be lost; and costs will incur from pump- ing irrigation water from deepening water levels and preventing seawater intrusion into our coastal aquifer systems. The state has seen similar crises before, particularly in Southern California, where groundwater basins are smaller, have more limited supplies, and had been overtapped soon after powerful turbine pumps were invented in the early 20th century. Extended, expensive court battles between thirsty urban neigh- bors have divided up the basins and resulted in adjudications that allocate specific amounts of water to specific groundwater users. The adjudications are administered through a local water master and have halted, if not reversed, the overdraft of these basins. A wide range of measures and complex arrangements between multiple stakeholders and the public have generated significant water conservation, development of alternative sur- face water supplies, and increased groundwater recharge and groundwater banking opportunities. In other regions of California, particularly in the Central Valley, groundwater overdraft continues, exacerbated by below- average, or well-below-average, precipitation in 6 of the past 8 years. In some areas, including Paso Robles and the eastern San Joaquin Valley, overdraft is a recent phenomenon caused by ag- riculture expanding into former rangelands and growers using either stream-fed flood and furrow irrigation or high-efficiency irrigation systems that rely on groundwater that lacks recharge from streams. Past droughts have provoked calls for groundwater action: In 1992, the California Legislature passed AB 3030, which en- couraged local agencies to collaborate and develop groundwa- ter management plans, though few guidelines were provided. Following another drought, the Legislature passed SB 1938 in 2002, which required those local agencies receiving state fund- ing for water projects to have a groundwater management plan in place. This time, the state provided guidelines on minimum standards that the plans needed to fulfill to receive a passing grade from the state’s Department of Water Resources (DWR). Following the 2007–2009 drought, the Legislature asked DWR to develop more rigorous groundwater level monitoring through- out the state, with the support of local agencies or initiatives. Significant improvements in groundwater management oc- curred in some areas. Local agencies began thinking and talking about managing their groundwater; education and outreach activities have been offered to stakeholders through various or- ganizations, including UC Cooperative Extension; and local ad- visory groups have engaged the public and the many local and regional agencies dealing with or affecting groundwater.