San Joaquin River

California Water Plan Update 2018, Supporting Documentation for Water Portfolios

California Department of Water Resources (DWR) | April 15th, 2019

California Water Plan Update 2018 (Update 2018) supporting documentation for water portfolios includes descriptions and accountings of water uses and their supplies for t

California Water Plan Update 2018 (Update 2018) supporting documentation for water portfolios includes descriptions and accountings of water uses and their supplies for the state in Figures 1 and 5, and for 10 hydrologic regions in Figures 7 through 16. They include pictures of conditions in California, along with water balance data for Water Years (WYs) 2011–2015. Regional inflow and outflow Figures 17 and 18 provide a geographic overview of California and surface water inflows and outflows with adjoining states, between hydrologic regions, and to the Pacific Ocean, for a wet year between two drought sequences, and a critically dry year in a drought sequence. More extreme and variable hydrology seems to have become the new normal, and not just for California. California has been, and will continue to be, a useful example of extremes brought on by a wide variety of climates and terrains. To better understand these diversities, plan for future needs, and move toward water resources sustainability, the California Department of Water Resources (DWR) analyzes water use and supply conditions for each water year at various spatial scales for the entire state. This accounting of water uses and supplies is the only statewide analysis that exists. The California Water Plan (Water Plan) water balance data is used by many in and out of the water community. Data and information requests come from other DWR programs, State and federal agencies, cities and counties, local water agencies and purveyors, research institutes, universities, non-governmental organizations, private sector companies, lawyers, elected officials, news media, documentaries, book writers, students, interested public, other states, and even other countries because California is recognized as a leader in integrated water resources management. The following excerpt is from Update 2018, Chapter 1, “California Water Today,” section on California’s Diverse Water Supplies and Uses.

California Water Plan Update 2023 (Final Version)

California Department of Water Resources (DWR) | April 3rd, 2024

Updated every five years, the Water Plan is the State’s strategic plan for sustainably and equitably managing, developing, and stewarding water resources. Required by W

Updated every five years, the Water Plan is the State’s strategic plan for sustainably and equitably managing, developing, and stewarding water resources. Required by Water Code Section 10005, the plan presents the status and trends of California’s water-dependent natural resources; water supplies; and agricultural, urban, and environmental water demands for a range of plausible future scenarios.

California Water Plan Update 2023 Public Review Draft

California Department of Water Resources (DWR) | September 20th, 2023

The California Water Plan (Water Plan), updated every five years, is the State’s strategic plan for sustainably and equitably managing, developing, and stewarding water

The California Water Plan (Water Plan), updated every five years, is the State’s strategic plan for sustainably and equitably managing, developing, and stewarding water resources. Required by Water Code Section 10005, the plan presents the status and trends of California’s water-dependent natural resources; water supplies; and agricultural, urban, and environmental water demands for a range of plausible future scenarios.

California Water Resilience Portfolio

State of California | July 28th, 2020

California water seen as environment issue, not North vs. South

Christian Science Monitor | June 13th, 1984

Sooner or later southern Californians are going to get more water from the north. And yet the newest proposal to do it has rekindled the political rift over water policy

Sooner or later southern Californians are going to get more water from the north. And yet the newest proposal to do it has rekindled the political rift over water policy that makes compromise difficult. The new plan would expand channels feeding the main north-south aqueduct, and it raises issues tinged with sentiment that is typically Californian. Traditionally labeled a north-south rivalry, the water issue today is more correctly an illustration of a statewide credo often that gives equal weight to the often conflicting goals of environ-mentalism and economic prosperity. Gov. George Deukmejian's water plan - called the ''through-delta canal'' - would increase water flowing through the Sacramento-San

California Wetland and Riparian Area Protection Policy Technical Memorandum No. 5: Stream Definition

San Francisco Estuary Institute (SFEI) | April 20th, 2016

With this memorandum, the Technical Advisory Team (TAT) recommends a definition of California streams to the Policy Development Team (PDT) of the State Water Quality Cont

With this memorandum, the Technical Advisory Team (TAT) recommends a definition of California streams to the Policy Development Team (PDT) of the State Water Quality Control Board (State Water Board) for its Wetland and Riparian Area Protection Policy (WRAPP). This memorandum does not recommend any process or procedure for identifying, delineating, or classifying streams, nor are such recommendations being planned by the TAT at this time. However, the TAT recommends that such processes and procedures should be developed in the future to support the WRAPP. The California Wetland Monitoring Workgroup (CWMW) is preparing recommendations for stream mapping as part of the recommending methodology of the California Aquatic Resource Inventory (CARI). 

California's Central Valley Groundwater Wells Run Dry During Recent Drought

American Geophysical Union (AGU) | February 27th, 2020

Declining water tables are causing wells to run dry in California, but the prevalence and spatial distribution of wells that have run dry are not known beyond anecdotal a

Declining water tables are causing wells to run dry in California, but the prevalence and spatial distribution of wells that have run dry are not known beyond anecdotal and voluntary reports. Here, we apply a new, simple, and measurement‐driven method to calculate a localized water table; we show, for the first time using observations, that up to one‐in‐five wells now runs dry in California's Central Valley. The spatial distribution of wells identified as having dried up replicates hot spots of wells identified as having run dry in a voluntary reporting system, while also capturing impacts on groundwater wells that have not reportedly run dry. We assess the rates of drilling throughout the Central Valley and find, surprisingly, that domestic wells are being drilled deeper at a rate that exceeds agricultural wells across much of the central Central Valley. Because new groundwater wells are costly (i.e., $10,000 to $100,000), we suggest explicitly considering dry wells in groundwater sustainability planning to protect homes and farms from the loss of access to reliable water supplies in the future.

California's Fifth Climate Change Assessment

State of California | October 19th, 2026

California’s Climate Change Assessments are a cornerstone of the state’s efforts to understand and prepare for a changing climate. Since 2006, California has publishe

California’s Climate Change Assessments are a cornerstone of the state’s efforts to understand and prepare for a changing climate. Since 2006, California has published four statewide assessments, each building the scientific foundation needed to understand climate risks and inform policies, investments, and resilience actions. California’s Fifth Climate Change Assessment (Fifth Assessment) builds on this foundation while responding to new direction from Senate Bill 1320 (Stern, 2020), which requires the State to report the projected impacts and risks of climate change across California at least every five years. Click here for regional reports, state agency reports, and topical reports

California's Fourth Climate Change Assessment Statewide Summary Report

Governor's Office of Planning and Research (OPR) | August 27th, 2018

California’s Fourth Climate Change Assessment (Fourth Assessment) advances actionable science that serves the growing needs of state and local-level decision-

California’s Fourth Climate Change Assessment (Fourth Assessment) advances actionable science that serves the growing needs of state and local-level decision-makers from a variety of sectors. This cutting-edge research initiative is comprised of a wide-ranging body of technical reports, including rigorous, comprehensive climate change scenarios at a scale suitable for illuminating regional vulnerabilities and localized adaptation strategies in California; datasets and tools that improve integration of observed and projected knowledge about climate change into decision- making; and recommendations and information to directly inform vulnerability assessments and adaptation strategies for California’s energy sector, water resources and management, oceans and coasts, forests, wildfires, agriculture, biodiversity and habitat, and public health. In addition, these technical reports have been distilled into summary reports and a brochure, allowing the public and decision-makers to easily access relevant findings from the Fourth Assessment. Click here for key findings brochure

California's Groundwater Conditions Semi-Annual Update: March 2023

California Department of Water Resources (DWR) | March 15th, 2023

These updates are part of the informational resources associated with DWR’s California’s Groundwater (Bulletin 118). This report uses groundwater data received electr

These updates are part of the informational resources associated with DWR’s California’s Groundwater (Bulletin 118). This report uses groundwater data received electronically by DWR as of February 15, 2022, through the conclusion of Water Year 2022, and the start of Water Year 2023.