We recently experienced the 5-year event of 2012-2016, and other notable historical droughts included 2007-09, 1987-92, 1976-77, and off-and-on dry conditions spanning more than a decade in the 1920s and 1930s. California is no stranger to drought; it is a recurring feature of our climate. The data is updated each Tuesday and released on Thursday. In the San Joaquin Valley, deep irrigation wells lowered groundwater levels—already 250 meters below the surface in places—putting it out of reach of shallower wells that provided thousands of people with drinking water. And it allows increased pumping if needed during drought, as long as no major problems result.
In January, the new agencies in 21 basins deemed critically overdrawn had to submit plans for achieving groundwater “sustainability” within 20 years. After that, smaller devices can be towed through fields or orchards for higher resolution images. Drought in California from 2000 - 2020. But it is evidence of a slow-motion disaster, the result of the region’s insatiable thirst for groundwater.For decades, farmers have relentlessly pumped groundwater to irrigate their crops, draining thick, water-bearing clay layers deep underground. (Local rules or court orders require metering in some basins to help resolve disputes.) Across the state, multiple government and private entities will need to work together on managing supply and demand at the scale of entire basins, in order to minimize the economic cost of using less water. Because of their duration and severity in terms of both lack of rainfall and runoff, the 1928-34 drought, which lasted 7 years, and the 1987-92 drought, which lasted 6 years, are compared to the 2012-16 drought, which lasted 5 years, to assess similarities and differences. For decades, some water districts have filled dedicated ponds in wet years so that the water percolates into the ground. Lower levels of groundwater caused problems and led to calls for better management.Still, researchers say truly protecting groundwater in California will require cutbacks in agriculture, which on average makes up about 80% of commercial and residential consumption. Decreasing groundwater levels lead to exposing of underground water storage areas, this will cause lack of soil structure strength and possible sinking if the land above is heavy enough. Drought is a gradual phenomenon, occurring slowly over a period of time. Years of drought have been wiped out by an active storm track in California this winter, and drought conditions have dramatically improved across the West. Information on subsidence is also helpful. Vineyards can tolerate spring flooding, and some crops, like alfalfa, do well with flood irrigation.
But a different source, stormwater runoff from urban or managed landscapes, could pose a problem: preventing contaminants—including farm fertilizers—from seeping into groundwater. GRACE measurements, combined with other data, indicated that in 2010 Central Valley aquifers held 20 cubic kilometers less water than they had in 2003.The Sustainable Groundwater Management Act, which became law in September 2014, was “an incredible step” for a state that had long resisted groundwater regulation, Famiglietti says. In the spring of 2015, the The drought led to Governor Jerry Brown's instituting mandatory 25 percent water restrictions in June 2015.Many millions of California trees died from the drought – approximately 102 million, including 62 million in 2016 alone.The winter of 2016–17 turned out to be the wettest on record in Northern California, surpassing the previous record set in 1982–83.Adaptation is the process of adjusting to circumstances, which means not trying to stop the drought, but trying to preserve the water given the drought conditions. But the push gained momentum from new satellite radar images that dramatically depicted the state’s subsidence problems.
California’s water resources agency recently committed $12 million to using the helicopter-mounted system in groundwater basins throughout the state.To adapt to that future, officials are pondering a new arrangement in which dam operators would release water ahead of rainstorms.
View DWR reports and publications in our document library.We provide educational publications to view, download, and order.We develop and maintain a number of state-of-the-art models and analytical tools.DWR maintains several additional web portals containing data and maps. In 2014, when NASA scientists flew radar equipment over the California Aqueduct, a critical piece of water infrastructure, they found that one section had dipped 20 centimeters over 4 months. That’s 10% to 25% of the annual statewide deficit, Fogg says.When drought empties reservoirs, such as Lake Cachuma near Santa Barbara, California, in 2015, groundwater can become an even more important source of water.Recharge water that comes from mountain reservoirs often has high quality. “It isn’t like an earthquake; it doesn’t happen, boom,” says Claudia Faunt, a hydrologist with the U.S. Geological Survey. During a recent intense drought, from 2012 to 2016, parts of the valley sank as much as 60 centimeters per year.
High temperatures worsened its effects, with 2014 and 2015 being the two hottest years in the state’s recorded history. Fisher has been studying ways to remove certain contaminants by adding biomatter such as wood mulch and almond shells to the soil at recharge sites. Hydrologic conditions causing impacts for water users in one location may not represent drought for water users in a different part of California, or for users with a different water supply. Many districts, for instance, aren’t sure how much water is being removed from the ground because California doesn’t require all pumps to have meters. Throughout history, California has experienced many droughts, such as 1841, 1864, 1924, 1928–1935, 1947–1950, 1959–1960, 1976–1977, 1986–1992, 2006–2010, and 2011–2019. Storage, whether in surface water reservoirs or in groundwater basins, buffers drought impacts and influences the timing of when drought impacts occur. 2012-2016 California Drought: Historical Perspective. Reservoirs in California are designed to control either rain floods, snowmelt floods or both. “The level of complexity that we’re capturing is amazing,” Knight says.