Understanding California’s Groundwater
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.

Note from the Authors

December 2014

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.

Articles in This Series

Infographics in This Series

Click on the links below to see, share, and republish infographics created for this series.

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.


Janny Choy

Research Analyst,
Water in the West

In her position as a research analyst with Water in the West, Janny helps the program to advance a vision for sustainable freshwater management in the American West through research and analysis into the science and policy of freshwater. More »

Tara Moran

Research Associate,
Water in the West

Tara’s research interests are in water resources and effective, sustainable groundwater management. Trained as a glaciologist and snow scientist, Tara is working with the center for Groundwater Evaluation and Management (GEM center) and the program on Water In the West.  
More »

Geoff McGhee

Creative Director,
Bill Lane for the American West

Geoff (@mcgeoff) develops infographics and multimedia at the Bill Lane Center for the American West. Previously a John S. Knight Journalism Fellow at Stanford, he has also worked at The New York Times, Le Monde, and ABCNews.com. More »

Leon Szeptycki

Executive Director,
Water in the West

An attorney who specializes in water quality, water use and watershed restoration, Leon’s work includes issues related to stream flow restoration in the context of the western appropriative rights system and increasing human demands on water. More »

Rebecca Nelson

Program Leader, Comparative Groundwater Law and Policy Program

Rebecca leads the Comparative Groundwater Law and Policy Program - a program of research and international symposia, focusing on legal and policy aspects of integrated groundwater management. The program concentrates on mechanisms for managing surface water and groundwater as one resource, taking into account the ecological context. More »

Melissa Rohde


Melissa is a research assistant for Water in the West and a graduate student in the Department of Civil & Environmental Engineering at Stanford University. Her research focuses on groundwater management in water-stressed regions. She attended the University of British Columbia for a Bachelor of Science in Biological Oceanography, and received her MSc in Water Science, Policy, and Management from Oxford University. She keeps a water blog on her website: More »

Justin Maynard


Justin was a Research Assistant for the Water in the West focusing on groundwater data collection and management. He attended UCLA for a Bachelor of Science degree in Civil and Environmental Engineering, and received a MS in Environmental Fluid Mechanics and Hydrology from Stanford University in December 2013. He now works as a water resources engineer.

Carolina Sanchez


Carolina was a Research Assistant for the Water in the West focusing on the groundwater-energy nexus. She attended Loyola Marymount University for a Bachelor of Science degree in Civil Engineering and received an MS in Environmental Fluid Mechanics and Hydrology from Stanford University in December 2013. She now works at Wildermuth Environmental, a specialized water resources consulting firm, in Lake Forest, California.

Paul Van Slembrouck

Creative Director, Halftone

Paul (@ptvan) graduated from Michigan's Ross School of Business. Drawing upon experience in finance, economics, advertising, and tech startups, he finds happiness in applying visualization design to challenges in all industries.

Michael Porath

Director of Strategy & Technology, Halftone

Michael (@poezn) graduated from UC Berkeley, where he also taught the theory and craft of information visualization to graduate students. Before realizing his love for visualizing data, Michael lead data driven engineering projects for a number of companies in the Swiss financial sector.

Halftone (@hlftn) is a Data Visualization Consultancy and Studio, which is based in San Francisco, CA. Founded in 2012, Halftone has helped organizations in a wide range of fields; from local technology startups to non-profit and advocacy based organizations, to international news publishers. For these articles on groundwater, Halftone has guided the process through concepts, data management, design, and implementation, in close collaboration with the team at Stanford’s Water in the West.

Jeremy Carlson

Principal, Carlson Design
(Groundwater Conflicts Map)

Jeremy (@eyesofjeremy) has been an independent graphic and web designer since 2001. He has worked with clients such as Trout Unlimited and Western Resource Advocates to explain environmental issues with elegance and authority.

Additional Credits

Water in the West, Stanford University
Prof. David Freyberg
Debra Perrone
Athena Serapio
Kira Minehart
Natalie Shell
Will Toaspern

Bill Lane Center for the American West, Stanford University
Stanford Woods Institute for the Environment
Christine Harrison
Terry Nagel
Keith Iverson

Reviewers and Additional Research
Timothy Parker, Parker Groundwater
Iris Priestaf, Todd Engineers
Chad Taylor, Todd Engineers
Julie Martin

Water in the West at Stanford University

Water in the West is a partnership of the faculty, staff, and students of the Stanford Woods Institute for the Environment and the Bill Lane Center for the American West. The mission of Water in the West is to design, articulate, and advance sustainable water management for the people and environment of the American West. Linking ideas to action, we accomplish our mission by engaging in cutting-edge research, creative problem solving, active collaboration with decision makers and opinion leaders, effective public communications, and hands-on education of students.
More at https://waterinthewest.stanford.edu.
Support for Understanding California's Groundwater was provided by the California Water Foundation