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 Future

Public Policy Institute of California (PPIC) | January 18th, 2018

Water management in California has always been challenging. The state’s variable climate is marked by long droughts and severe floods, with stark regional differences i

Water management in California has always been challenging. The state’s variable climate is marked by long droughts and severe floods, with stark regional differences in water availability and demand. California has adapted by building a vast network of storage and conveyance facilities to deliver water from the wetter parts of the state to population and farming centers in the Bay Area, the San Joaquin Valley, and Southern California. The Sacramento–San Joaquin Delta is a fragile link in the state’s water supply network, and a plan to address supply reliability, known as California WaterFix, faces many hurdles. California’s extensive network of dams is aging. Agricultural demand is becoming less flexible, as farmers are increasing tree crops (especially nuts), which must be watered every year. Conflicts are growing between human water use and water needed to support fish and other wildlife. And the latest cycle of droughts and floods provides a glimpse of an uncertain future under climate change. California’s water management challenges are complex, but they can be addressed. Solutions will involve difficult and sometimes costly trade-offs, as well as contentious legal and political changes.

California’s Agricultural and Urban Water Supply Reliability and the Sacramento–San Joaquin Delta

University of California, Davis (UC Davis) | October 13th, 2016

Much of the water supplied in California for agriculture and cities is taken directly from the Sacramento–San Joaquin Delta (Delta) or indirectly from surface and groun

Much of the water supplied in California for agriculture and cities is taken directly from the Sacramento–San Joaquin Delta (Delta) or indirectly from surface and groundwater diversions upstream. These water supplies have great economic and social value, and considerable ecosystem effects. Long thought of as the major source of water for economic growth in California, the reliability of water supplied from the Delta is threatened by drought, flood, climate change, earthquakes, growing water demands, and deteriorating conditions for endangered species and native ecosystems. Research in recent years has improved understanding of how management of the Delta ties together the quantity and quality of water available statewide. These ties run from the Sierra mountains and coastal streams, through the Central Valley, to the San Francisco Bay Area, and over the Tehachapi Mountains to southern California. For decades, Californians counted on reducing Delta outflows to supply water for growing water demands in its watershed and in water importing areas. With greater competition for water, concern for environmental effects, and a changing climate, the reliability of such supplies is now diminishing. This must lead to tighter accounting and modeling of water supplies in the Delta and throughout its watershed. This paper reviews issues about Delta water supplies, operations, regulations, and reliability; the economic value of supply; costs of unreliability in quantity and quality; and several directions for further scientific and technical work on water supply reliability.

California’s Future: Water

Public Policy Institute of California (PPIC) | January 31st, 2020

Water management in California has always been challenging. The state’s variable climate is marked by long droughts and severe floods, with stark regional dif

Water management in California has always been challenging. The state’s variable climate is marked by long droughts and severe floods, with stark regional differences in water availability and demand. California’s “water grid”—the network of surface and groundwater storage and conveyance systems that connects most water use in the state—was designed to move water to population and farming centers in the Bay Area, the San Joaquin Valley, and Southern California, while also protecting residents from floods. As the state has changed, its water challenges have intensified. The Sacramento–San Joaquin Delta is an increasingly fragile link in the water grid. California’s extensive network of dams is aging. Agricultural demand is becoming less flexible, as farmers increase tree crops (especially nuts), which must be watered every year. Some poor—mostly rural— communities lack safe drinking water. Conflicts are growing between human water use and water needed for fish and other wildlife. And the latest cycle of droughts and floods highlights the growing threat of climate change. Climate pressures are making it harder to simultaneously store water for droughts, manage flood risk, and protect fresh- water ecosystems. But leaders across the state are addressing the challenges of a more volatile climate, and the Newsom administration is developing a water resilience portfolio to adapt all aspects of water management to the “new normal.”

California’s Water: The Sacramento-San Joaquin Delta

Public Policy Institute of California (PPIC) | October 1st, 2016

The Delta is the deteriorating, fragile hub of California’s water supply system. Critical decisions about its future are pending. This brief looks at various approa

The Delta is the deteriorating, fragile hub of California’s water supply system. Critical decisions about its future are pending. This brief looks at various approaches being proposed to improve management and health of the Delta. This publication is part of a briefing kit that summarizes a dozen of the state’s most pressing water management issues.

CalSim 3 Results for 2070 Climate Change and Sea Level Projections and Sensitivity Analysis

California Department of Water Resources (DWR) | January 17th, 2024

This Technical Memorandum (TM) summarizes the key findings from a sensitivity analysis performed to analyze operations of the proposed Delta Conveyance Project (DCP) and

This Technical Memorandum (TM) summarizes the key findings from a sensitivity analysis performed to analyze operations of the proposed Delta Conveyance Project (DCP) and potential project water supply benefits under a range of potential scenarios for 2070 conditions. These scenarios consider climate change, sea level rise (SLR), and various water management responses. In addition, this sensitivity analysis also helps to identify whether proposed project operations and potential project impacts detailed in the Final DCP Environmental Impact Report (EIR) would remain similar or differ under a different climate change and SLR scenario under 2070 conditions, a more distant future.

CalSim II Simulation of Historical SWP-CVP Operations Technical Memorandum Report

California Department of Water Resources (DWR) | November 12th, 2003

CalSim is a generalized water resources planning tool developed jointly by the Department of Water Resources (DWR) and the US Bureau of Reclamation Mid-Pacific Region (Re

CalSim is a generalized water resources planning tool developed jointly by the Department of Water Resources (DWR) and the US Bureau of Reclamation Mid-Pacific Region (Reclamation). CalSim II is the application of the CalSim software to model the State Water Project (SWP), the federal Central Valley Project (CVP) and areas tributary to the Sacramento-San Joaquin Delta (Delta). The primary purpose of the CalSim II model is to evaluate the water supply reliability of the CVP and SWP, 1) at current or future levels of development, 2) with and without various assumed future facilities and, 3) with different modes of facilities operations. The purpose of the Historical Operations Study is to evaluate the ability of CalSim-II to represent CVP and SWP operations, in general, and the delivery capability of the projects, in particular, through the monthly simulation of recent historical conditions. The Historical Operations Study is part of a larger CalSim II evaluation process. Other components of the evaluation include a survey of the water community to gather their views and opinions of the model, a model peer review by leading academics and practitioners, and a sensitivity analysis on model inputs. It is hoped that this effort, to assess the quality and limitations of CalSim II, will lead to a wider debate about critical model issues, help direct model development in both the near and long term, and eventually lead to greater public confidence and acceptance of the model.

Carbon Sequestration and Subsidence Reversal in the Sacramento–San Joaquin Delta and Suisun Bay: Management Opportunities for Climate Mitigation and Adaptation

University of California, Davis (UC Davis) | August 28th, 2023

Case History No. 9.14. Santa Clara Valley, California, U.S.A.

United Nations Educational, Scientific and Cultural Organization (UNESCO) | June 30th, 1984