North Lahontan

Bulletin 118 - California's Groundwater Update 2013

California Department of Water Resources (DWR) | April 15th, 2015

California’s Groundwater Update 2013 compiles and analyzes readily available groundwater information to characterize California’s groundwater basins, aquifers, and we

California’s Groundwater Update 2013 compiles and analyzes readily available groundwater information to characterize California’s groundwater basins, aquifers, and well infrastructure. It also presents data and analysis related to groundwater monitoring efforts, aquifer conditions in response to extraction, groundwater management practices, and conjunctive management programs. It expands and enhances baseline groundwater information on a regional scale, identifies challenges associated with sustainable groundwater management, and helps guide implementation of diverse resource management strategies. The set of data, information, and analysis developed can help local and regional groundwater managers, as well as individual well owners, better understand California’s hidden and commonly misunderstood resource. This Bulletin has been uploaded in the following separate files reflecting hydrologic regions and appendices. Chapter One / Introduction  Chapter Two / State-wide Update  Chapter Three / North Coast Chapter Four / San Francisco Bay Chapter Five / Central Coast Chapter Six / South Coast  Chapter Seven / Sacramento River Chapter Eight / San Joaquin River Chapter Nine / Tulare Lake Chapter Ten / North Lahontan Chapter Eleven / South Lahontan Chapter Twelve / Colorado River Appendix A: Methods and Assumptions Appendix B: CASGEM Basin Prioritization Appendix C: Groundwater Use Data 2010-2015 Appendix D: Conjunctive Management Survey Appendix E: Change in Groundwater in Storage Appendix F: Subsidence

Bulletin 118: California's Groundwater Update 2020 (draft)

California Department of Water Resources (DWR) | March 1st, 2021

Groundwater is a precious and limited resource that is used in meeting the needs of California’s large and small urban areas, rural groundwater users, irrigated agricul

Groundwater is a precious and limited resource that is used in meeting the needs of California’s large and small urban areas, rural groundwater users, irrigated agriculture, and the environment. Since the last California’s Groundwater (CalGW) Update in 2003, there has been significant changes to land use, water use, water application practices, and water allocations. In addition, the effects of climate change have affected California’s reliance on groundwater. It is expected that there will be additional changes in land use, water use, adjustments in water allocations, and that climate change will continue to affect the environment, thus elevating the importance of the reporting in CalGW Updates.  According to the last comprehensive report, California’s Groundwater Update 2003 (CalGW Update 2003), California’s reliance on groundwater was approximately 30 percent during a wet-to-average precipitation water year and approximately 40 percent during dry periods. Since then, the percentage of groundwater reliance has increased to between 30 and 40 percent during above normal to-wet years and to as much as 58 percent during dry periods (California Department of Water Resources 2018).

Bulletin 16, Report on Weather Modification Operations in California, July 1952-June 1956

California Department of Water Resources (DWR) | January 1st, 1957

Bulletin 161-2025, 2025 Annual Water Supply and Demand Assessment Summary Report

California Department of Water Resources (DWR) | September 23rd, 2025

This report summarizes the Department of Water Resources’ (DWR’s) review of Urban Water Suppliers’ Annual Water Shortage Assessment Reports (Annual Shortage Reports

This report summarizes the Department of Water Resources’ (DWR’s) review of Urban Water Suppliers’ Annual Water Shortage Assessment Reports (Annual Shortage Reports) for the State Water Resources Control Board (State Water Board). As directed by the California Water Code (CWC) §10644(c)(1)(B), this summary report includes water shortage information at the supplier level, as well as regional and statewide analyses of water supply conditions. 

Bulletin 17-00, Dams within Jurisdiction of the State of California

California Department of Water Resources (DWR) | July 31st, 2000

Bulletin 17-65, Dams within Jurisdiction of the State of California

California Department of Water Resources (DWR) | August 31st, 1965

Bulletin 17-71, Dams within Jurisdiction of the State of California

California Department of Water Resources (DWR) | October 29th, 1971

Bulletin 17-74, Dams within Jurisdiction of the State of California

California Department of Water Resources (DWR) | May 31st, 1974

Bulletin 17-79, Dams within Jurisdiction of the State of California

California Department of Water Resources (DWR) | December 29th, 1979

Bulletin 17-84, Dams within Jurisdiction of the State of California

California Department of Water Resources (DWR) | August 31st, 1984