Understanding California’s Groundwater
Our series explores groundwater management in California through new research into key groundwater issues, interactive graphics and a synthesis of existing knowledge on groundwater in California, all designed to advance public understanding of this critical issue.
Two major developments in California water policy took place after this series was published: in September, Gov. Jerry Brown signed into law the Sustainable Groundwater Management Act of 2014, a measure to create a comprehensive groundwater management framework for the state; and on November 4, voters approved Proposition 1, a $7.5 billion bond measure seeking to increase water supply and water resilience throughout the state, in the face of climate change and an ongoing three-year drought.
We have added notes to relevant articles to reflect the implications of those recent developments.
Contrary to a popular misconception of an underground river or lake, groundwater is found in the tiny spaces between sand and gravel and rock.
Before a wet February, the 2013-14 water year in California was on its way to being the driest on record.
Groundwater levels have dropped 50 feet below historical lows, with levels in many areas in the San Joaquin Valley more than 100 feet below previous historical lows
Central Valley aquifers lost 140 cubic kilometers of freshwater – an amount roughly four and a half times the capacity of Lake Mead in Nevada, the nation’s largest reservoir.
Aqueducts and reservoirs distribute surface water from the mountains through the Sacramento-San Joaquin Delta, and on to the Central Valley and points far south.
Total scores on groundwater data collection and sharing across the state as a whole were low, with 9 of the 10 hydrologic regions scoring less than 5 out of a possible 10 points. The South Lahontan hydrologic region scored the highest with 6 points.
Water in the West researchers obtained all available grant applications submitted to DWR for the four recharge-related grant programs listed above. This new study evaluated 136 grant applications filed over the past 14 years
Based on our dataset of 55 conflicts drawn from publicly available information collected from 2008-2012, the map shows where these conflicts occur, what the problems are, and how they are dealt with.
