Review of the Long-Term Operations of the Central Valley Project and the State Water Project

National Academy of Sciences (NAS) | November 10th, 2025

The CVP and SWP (referred to collectively as “the Projects”) rarely deliver their full contracted  amount of water. Some of this is inherent in the operation of larg

The CVP and SWP (referred to collectively as “the Projects”) rarely deliver their full contracted  amount of water. Some of this is inherent in the operation of large water projects with diverse demands in a dry and highly variable climate. A growing, complex regulatory environment of state and federal laws, some of which were created to protect fish species endemic to the Delta, has further restricted CVP and SWP operations.  These fish include the southern distinct population segment of North American green sturgeon, California Central Valley steelhead, Central Valley spring-run Chinook salmon, Sacramento River winter-run Chinook salmon, longfin smelt, and Delta smelt. Operating the Projects while trying to prevent species extinction can be a source of conflict if the actions to prevent extinction reduce the amount of water that can be exported. Project operation into the future will likely become more challenging as changes in various climatic factors push the listed species closer to their thresholds of survivability. Hence, in late 2023 USBR contracted with the National Academies of Sciences, Engineering, and Medicine (NASEM) to form an expert committee that could serve as an independent review for the CVP and SWP as they operate into the future. The Committee’s statement of task appears in Box S-1. The three actions chosen for the study—the Shasta Coldwater Pool Management Action, the Old and Middle River Flow Management Action, and the Summer-Fall Habitat Action for Delta Smelt— are perceived as consequential for species survival and controversial for their effects on water deliveries to contractors.

Review of the Monitoring Enterprise in the Sacramento-San Joaquin Delta

Delta Stewardship Council (Delta Council) | March 3rd, 2022

Review of the Monitoring Enterprise in the Sacramento-San Joaquin Delta Summary Sheet

Delta Stewardship Council (Delta Council) | April 28th, 2022

Review of Water Supply Reliability Estimation Related to the Sacramento-San Joaquin Delta

Delta Stewardship Council (Delta Council) | June 16th, 2022

Revised Incidental Take Methodology for the Coordinated Long-Term Operation of the CVP and SWP

U.S. Fish and Wildlife Service (FWS) | January 30th, 2019

Revised Water Right Decision 1641

California State Water Resources Control Board (SWRCB) | December 29th, 1999

Reviving Central Valley Rivers

CALFED | June 1st, 2003

RipZET: Documentation of Tool Demonstration in Marin County

San Francisco Estuary Institute (SFEI) | March 31st, 2015

The San Francisco Estuary Institute and Aquatic Science Center (SFEI‐ASC) has developed the Riparian Zone Estimation Tool (RipZET) to help the California community of

The San Francisco Estuary Institute and Aquatic Science Center (SFEI‐ASC) has developed the Riparian Zone Estimation Tool (RipZET) to help the California community of riparian interests visualize and characterize riparian areas as habitat unto themselves as well as their capacity to function as buffers for protecting the ecosystem services of the state’s streams, lakes and wetlands. RipZET is a tool used with Geographic Information System (GIS) and spreadsheet software to estimate “functional riparian width,” or the width associated with different riparian functions (e.g., large woody debris input, shading, floodwater storage), which varies with channel type and watershed location. The concept of functional riparian width is central to the riparian definition recommended by the National Research Council (NRC 2002) and is integral in many recently developed riparian design and management guidelines around the country.

Risk-Informed Future Climate Scenario Development for the State Water Project Delivery Capability Report

California Department of Water Resources (DWR) | August 24th, 2023

This report introduces and documents an extensive effort undertaken by the California Department of Water Resources (DWR) to develop risk-informed future climate scenario

This report introduces and documents an extensive effort undertaken by the California Department of Water Resources (DWR) to develop risk-informed future climate scenarios for the State Water Project (SWP) Delivery Capability Report (DCR), a report issued by the SWP every two years. These reports present DWR’s analysis of the SWP system and planning information for users of SWP water. The analysis provides information about how climate change, regulatory, and operational considerations affect SWP delivery capability. Specifically, the report must provide “…under a range of hydrologic conditions, the then existing overall delivery capability of the project facilities and the allocation of that capacity to each contractor. The range of hydrologic conditions shall include the historic extended dry cycle and long-term average.” (Settlement Agreement 2003).

Root Causes Analyses of the Oroville Dam Gated Spillway Failures and Other Developments

University of California, Berkeley (UC Berkeley) | July 20th, 2017

We have performed forensic Root Causes Analyses of the Oroville Dam Gated Spillway failures and other associated developments as unfunded (approximately 3,000 pro-bono h

We have performed forensic Root Causes Analyses of the Oroville Dam Gated Spillway failures and other associated developments as unfunded (approximately 3,000 pro-bono hours) volunteers of the University of California at Berkeley (UCB) Center for Catastrophic Risk Management (CCRM) Oroville Dam Advisory Group (ODAG). We initiated this work on January 27, 2017. The results contained in this report have been developed based on the currently available public document and information sources cited at the end of this report, included in the Preliminary Root Causes Analysis of the Failures of the Oroville Dam Gated Spillway report dated April 17, 2017, and in the Legislative Oversight Report: Oroville Dam report dated May 11, 2017.  This report documents our analyses of the Root Causes of the initial failure of the Gated Spillway. Appendix A of this report provides summaries of the procedures and processes we used to perform the Root Causes analyses, background on the components that comprise Engineered Systems, and background on the Human and Organizational Factor malfunctions (errors) responsible for failures of Engineered Systems. Appendix B provides details of our analyses of the Physical and Organizational Root Causes of the initial failure of the Gated Spillway. The opinions expressed in this Report are ours alone. The opinions expressed herein are a fair and accurate summary of our opinions, based upon our experience, education, training, and expertise.