Sacramento River

CVFPP Conservation Strategy Appendix I. Floodplain Restoration Opportunity Analysis

California Department of Water Resources (DWR) | July 14th, 2016

As part of the Conservation Strategy for the 2017 Central Valley Flood Protection Plan (CVFPP), a continuation of the Floodplain Restoration Opportunity Analysis (FROA) (

As part of the Conservation Strategy for the 2017 Central Valley Flood Protection Plan (CVFPP), a continuation of the Floodplain Restoration Opportunity Analysis (FROA) (DWR 2012a) was conducted to develop, identify, and prioritize potential locations for implementing management actions. Two types of management actions were considered in this analysis: modification of floodplain topography (specifically, lowering floodplain topography through targeted excavation) and levee relocation (specifically, constructing setback levees). Preliminary areas for floodplain modification and setback levees were identified within the Systemwide Planning Area (SPA) of the State Plan of Flood Control (SPFC) (Figure 1-1). The following technical memorandum documents the goal, objectives, methods, and results of this analysis.

CVFPP Conservation Strategy Appendix J. Existing Conservation Objectives from Other Plans

California Department of Water Resources (DWR) | July 14th, 2016

The Conservation Strategy, in conjunction with the Central Valley Flood Protection Plan (CVFPP), geographically overlaps with multiple regional and collaborative conserva

The Conservation Strategy, in conjunction with the Central Valley Flood Protection Plan (CVFPP), geographically overlaps with multiple regional and collaborative conservation plans that have been implemented or are planned for the Sacramento and San Joaquin Valleys. Regional planning efforts such as the Conservation Strategy are most effective when coordinated with similar programs and plans, in terms of both cost efficiency and ecological benefit. For example, knowledge gained through implementation of existing plans has refined the Conservation Strategy’s objectives and approaches. Additionally, during strategy implementation, collaboration with other planning efforts will provide greater opportunities for effective, integrated, landscape-level conservation. This could support achievement of individual plans’ important ecological objectives, such as improving habitat connectivity and increasing the size of habitat preserves. In other words, the collaborative approach will allow the Conservation Strategy to contribute to the shared objectives of the other plans while meeting its own objectives.  The purpose of this appendix is to describe completed and ongoing planning efforts that have regional, geographically based, or quantifiable conservation measures that may be relevant to the Conservation Strategy. All of the plans and programs described overlap at least partially with the Systemwide Planning Area (SPA). The list presented herein is not comprehensive, but provides examples of efforts that were considered in developing the Conservation Strategy. In this appendix, completed planning efforts are summarized first, followed by those that are in progress. Potential relationships between these plans or programs and the Conservation Strategy are summarized in Table 1-1. Some programs, such as efforts to identify total maximum daily loads or implement Integrated Regional Water Management Plans, may support conservation work, but their objectives are dissimilar to those of the Conservation Strategy (i.e., focused on meeting water quality standards), so were not included.  This appendix is not intended to present an analysis of each plan in detail. Rather, the intent is to identify areas of potential overlap between relevant plans and the Conservation Strategy. As the Conservation Strategy is implemented, potentially synergistic areas and areas of possible conflict between the Conservation Strategy and individual plans can continue to be identified.  This appendix supports and recognizes considerations that will be essential as the Conservation Strategy is implemented. Specifically, this appendix:  • efficiently uses current information to inform the Conservation Strategy regarding potential conservation goals; recognizes that multiple conservation plans and collaborative planning efforts have been completed, are in development, or are being implemented: in whole or in part, the plans address many of the targeted species and habitats that occur in the SPA, and the plans help identify conservation needs and priorities in the flood risk management system; highlights potential conservation partnerships for the California Department of Water Resources (DWR) in implementing the Conservation Strategy, by: describing opportunities to share costs on conservation projects and describing opportunities for DWR to simultaneously meet its own conservation goals and contribute to plans or programs through specific projects; and identifies completed conservation planning efforts, from which “lessons learned” can be applied to Conservation Strategy implementation

CVPIA 10 Years of Progress

U.S. Bureau of Reclamation (USBR) | June 27th, 2015

In 1992, Congress passed the Central Valley Project Improvement Act (Act, or CVPIA), which amended previous authorizations of the California Central Valley Project (CVP)

In 1992, Congress passed the Central Valley Project Improvement Act (Act, or CVPIA), which amended previous authorizations of the California Central Valley Project (CVP) to include fish and wildlife protection, restoration, enhancement, and mitigation as project purposes having equal priority with power generation, and irrigation and domestic water uses. Congress directed the Secretary of the Interior, through the Bureau of Reclamation (Reclamation) and the U.S. Fish and Wildlife Service (Service), to operate the CVP consistent with the purposes of the Act, to meet the Federal trust responsibilities to protect the fishery resources of affected Federally recognized Indian tribes, and to achieve a reasonable balance among competing demands for use of CVP water. For the past 10 years, Reclamation and the Service, working together to implement the CVPIA, have embarked on one of the Nation’s largest fish and wildlife restoration efforts. Reclamation and the Service have developed programs to improve environmental conditions and modify operations, management, and physical facilities, and thus, the associated environmental conditions of the CVP to comply with the purposes and goals of the Act. All of the Act’s restoration measures are planned and implemented by Reclamation and the Service and coordinated with the State of California, CALFED, and other partners. In the following pages, you will find a summary of the protection, restoration, enhancement, and mitigation measures that have been implemented as of the end of fiscal year 2002, demonstrating the contributions Reclamation and the Service have made to the Central Valley. As you read the summary, it should become clear that progress is being made in unprecedented programs, and advancements have been made in resolving complicated watershed issues throughout the Central Valley. Yet much work lies ahead.

Dams within Jurisdiction of the State of California

California Department of Water Resources (DWR) | October 31st, 2023

Data to Decisions: How to Make Science More Relevant for Management of the San Francisco Estuary

University of California, Davis (UC Davis) | March 23rd, 2023

Dealing with the Delta: Envisioning Futures, Finding Solutions (Research Brief)

Public Policy Institute of California (PPIC) | February 15th, 2007

This research brief summarizes a report by Jay Lund, Ellen Hanak, William Fleenor, Richard Howitt, Jeffrey Mount, and Peter Moyle, Envisioning Futures for the Sacramento�

This research brief summarizes a report by Jay Lund, Ellen Hanak, William Fleenor, Richard Howitt, Jeffrey Mount, and Peter Moyle, Envisioning Futures for the Sacramento–San Joaquin Delta.

Debris-Restraining Barriers of the Yuba River

Scientific American | November 19th, 1904

In the years following the discovery of gold in California, the processes of mining for this precious metal caused the removal of vast quantities of detritus from the w

In the years following the discovery of gold in California, the processes of mining for this precious metal caused the removal of vast quantities of detritus from the western slopes of the Sierra Mountains into the streams and rivers of the valleys below. Gold was found in the beginning in gravel beds, where it had probably been deposited by rivers flowing in prehistoric times. These gravel beds exist in great numbers in a comparatively small area along the western slopes of the Sierra Mountains near the headwaters of streams draining into the Sacramento and San Joaquin valleys. In securing gold from these mountains the sorting action of water was necessary, and in order to facilitate mining operations. ditches of great length and size were built, frequently at great expense, to carry water to the localities where gold had been discovered. Streams of water under great pressures were directed at these gravel banks through nozzles sometimes as large as nine inches in diameter, to break down the gravel banks and wash the detritus through sluice ways where the gold could be caught. Streams carry ing as much as 3,500 miner's inches were not uncommon. It is thus easily seen that such powerful agencies would rapidly wash down whole hillsides, which would naturally be carried into the canyons and small streams in the vicinity of the mines, to be washed farther and farther down stream with each succeeding rainy season. These mining operations were carried on for a number of years without interruption until the valley country below became more thickly populated, when the injuries caused to the rivers and the neighboring farm lands became important enough to cause those damaged to seek legal redress.

Decadal Shifts in Groundwater Age Detected by Environmental Tracers Across California

American Geophysical Union (AGU) | March 23rd, 2026

Groundwater age tells us how long water has been underground since it last infiltrated the land surface. Monitoring changes in groundwater age helps identify aquifer stre

Groundwater age tells us how long water has been underground since it last infiltrated the land surface. Monitoring changes in groundwater age helps identify aquifer stress from pumping or shifts toward new hydrologic conditions—key factors for sustainable water management. In this study, changes in groundwater age were tested by comparing chemical tracer data collected about 10 years apart from hundreds of wells across California. Chemical tracers are dissolved substances with known historical records and decay rates that can be used to infer groundwater age. Using models that estimate expected tracer concentrations under steady-age conditions, this study found that nearly one-third of the wells showed significant changes in groundwater age over time. These changes were most common in areas with heavy agricultural use, where pumping and irrigation have altered how water moves underground. These shifts in age can also affect water quality, especially when younger water carries contaminants like nitrate. By using a statistical modeling approach, this study shows how changes in groundwater age can help identify aquifers under stress and support efforts to manage groundwater sustainably.

Decadal trends in the quality of groundwater used for public drinking-water supply in California, 2004–2023, California groundwater ambient monitoring and assessment program, priority basin project

U.S. Geological Survey (USGS) | February 25th, 2026

This study provides a comprehensive assessment of decadal changes in the quality of groundwater used for public drinking-water supply at 444 monitoring site

This study provides a comprehensive assessment of decadal changes in the quality of groundwater used for public drinking-water supply at 444 monitoring sites across California during 2004–2023. We assessed decadal step trends in groundwater quality for 145 water-quality constituents and geochemical indicators statewide and across geographic and land-use based network groups. We evaluated the statistical significance of directional changes (predominant increase or decrease of constituent concentrations) and the magnitude of those changes across all network groups. Uranium showed the most widespread directional and high-magnitude increases of all constituents with regulatory benchmarks statewide, particularly in the agriculture-dominated Central Valley as well as urban- and desert-dominated regions of Southern California. Fluoride and perchlorate showed the most widespread directional and high-magnitude decreases of all constituents with regulatory benchmarks statewide, which were also most pronounced in Southern California. Although arsenic and nitrate did not often register significant directional changes across network groups, they showed widespread, high-magnitude changes in both directions (increase and decrease) at levels often exceeding 10 percent of respective regulatory benchmarks statewide. Triazine herbicides (atrazine and simazine) and the gasoline oxygenate methyl tert-butyl ether (MTBE) showed significant directional decreases statewide, but not at levels considered to be of high magnitude compared to respective regulatory benchmarks. We observed significant directional and high-magnitude increases of total dissolved solids (TDS) statewide, which were most pronounced in agricultural areas. Analysis of explanatory geochemical indicators indicated that prevalent statewide increases of alkalinity and calcium were the predominant components of the observed statewide increases in TDS by mass. Widespread increases in groundwater alkalinity and calcium across agricultural and urban areas may be related, in part, to warm-season irrigation and other anthropogenic factors that have shifted soil weathering dynamics over the long term. Increasing alkalinity concentrations were related to increasing uranium concentrations, particularly in areas with aquifer materials derived from granitic rocks. Conversely, increasing calcium concentrations were related to decreasing fluoride concentrations, particularly in areas where fluoride occurred naturally at elevated concentrations. Decrease of perchlorate, triazine herbicides, and MTBE are likely related to decreased anthropogenic source inputs over time and natural attenuation in aquifers.

Decadal trends in the quality of groundwater used for public drinking-water supply in California, 2004–23

U.S. Geological Survey (USGS) | July 30th, 2026

This study provides a comprehensive assessment of decadal changes in the quality of groundwater used for public drinking- water supply at 444 monitoring sites across Cali

This study provides a comprehensive assessment of decadal changes in the quality of groundwater used for public drinking- water supply at 444 monitoring sites across California during 2004–23. We assessed decadal step trends in groundwater quality for 145 water- quality constituents and geochemical indicators statewide and across geographic and land- use based network groups. We evaluated the statistical significance of directional changes (predominant increase or decrease of constituent concentrations) and the magnitude of those changes across all network groups.