Delta Operations for Salmonids and Sturgeon (DOSS) Technical Working Group

Delta Stewardship Council (Delta Council) | November 1st, 2018

Delta Reclamation District Financing and Budgets

Delta Stewardship Council (Delta Council) | August 16th, 2016

This report explains the financing of the 93 reclamation districts that maintain the Delta’s levees. Reclamation districts’ primary method for raising funds is thr

This report explains the financing of the 93 reclamation districts that maintain the Delta’s levees. Reclamation districts’ primary method for raising funds is through assessments, which are levied on a per-acre basis upon property owners within a district’s boundaries. Assessments are subject to Proposition 218 procedures, and they must be approved by a vote of the affected people. A second financing tool that reclamation districts have is charging fees for services, such as irrigation or drainage services for landowners. In addition to relying on these direct financing tools, reclamation districts can also receive funds from the State or from other entities. According to data from the State Controller’s office, the median Delta reclamation districts have annual budgets of around $370,000, with property assessments serving as the primary source of revenue. Typical assessments in these districts are about $32 per acre. State funding is a supplementary source of revenue for these districts, making up about 30 percent of total revenues. On the expenditure side, more than 80 percent of typical reclamation districts’ expenditures are for “services and supplies,” which includes levee work, but also other expenses. Only 12 Delta reclamation districts have long-term debt, so State funding appears to have been successful in helping Delta reclamation districts avoid overly burdensome debt levels. The State has concentrated its reclamation district funding on certain strategic islands. Ten reclamation districts have received 62 percent of state funding over the past five years. These 10 reclamation districts that receive the most state funding also tend to have much higher property assessment rates compared to other reclamation districts. This suggests that reclamation districts are increasing their assessment rates as the State steps up its funding. Finally, reclamation districts receiving a large amount of state funds also spend much more on services and supplies, even after controlling for the size of the reclamation district. This difference suggests that reclamation districts that are not receiving significant funding from the State are primarily paying for levee maintenance projects rather than undertaking large-scale levee improvement projects.

Delta Region Integrated Flood Management: Key Considerations and Statewide Implications

California Department of Water Resources (DWR) | September 1st, 2012

This Background / Reference Memorandum (BRM) presents highlights from flood-related technical, legislative and funding information regarding the Sacramento-San Joaquin De

This Background / Reference Memorandum (BRM) presents highlights from flood-related technical, legislative and funding information regarding the Sacramento-San Joaquin Delta (Delta), with emphasis on activities by the California Department of Water Resources (DWR). The BRM is intended to provide historical and existing conditions (year 2011) context for DWR’s use in conveying strategies for future investments in integrated flood management in the Delta under a separate document. The State of California has entrusted DWR as the agency with the responsibility for managing water flow through the Delta and for representing State interests in Delta levees. DWR invests in the Delta levee system to protect clear and identifiable State interests, including but not limited to: • Human life, public health, and property within the Delta; • Water quality and water supply for agriculture, ecosystem, and municipal and industrial water users within the Delta and water users outside of the Delta; • Ecosystem protection and enhancement, including protection and recovery of threatened and endangered species; • Critical infrastructure such as highways, railroads, aqueducts, and pumping plants; • Other infrastructure such as transmission lines (electric & petroleum), shipping channels, and public infrastructure (water and wastewater treatment plants); • Agriculture and recreation; and • Cultural, historical, aesthetic, and other values included in “Delta as a place.” State legislation and modifications to the California Water and Public Resources codes have repeatedly demonstrated the State’s interest in preserving the Delta and the importance of Delta levees. The legislation and modifications to the codes have made strong statements about the importance of the Delta, provided direction for the DWR’s levee programs, and provided funding for flood management activities and environmental stewardship in the Delta. This BRM should be considered a reference document. Due to the large number of existing documents on the Delta and its levees, this BRM provides highlights of important material with references to other documents for more detailed information. This base information should be useful when considering modifications to investment strategies for integrated flood management in the Delta.

Delta smelt resiliency strategy

California Department of Water Resources (DWR) | July 11th, 2016

The Delta Smelt Resiliency Strategy (Strategy) is a science-based document that has been prepared by the State of California (State) to voluntarily address both immediate

The Delta Smelt Resiliency Strategy (Strategy) is a science-based document that has been prepared by the State of California (State) to voluntarily address both immediate and near-term needs of Delta Smelt, to promote their resiliency to drought conditions as well as future variations in habitat conditions. The Strategy relies on the MAST Report and Conceptual Models (IEP 2015) to articulate a suite of actions that can be implemented in the next few years that are intended to benefit Delta Smelt. Although the feasibility and effectiveness of each action included in the Strategy requires further exploration and study, the Strategy is an aggressive approach to implementing any actions that can be implemented in the near term, can be implemented by the State with minimal involvement of other entities, and have the potential to benefit Delta Smelt. State agencies that could implement this Strategy include Department of Water Resources (DWR), Department of Fish and Wildlife (DFW), and Division of Boating and Waterways (DBW). Several of the actions identified in this Strategy could also benefit other species, and coordination across various resource management agencies as appropriate may allow for benefits beyond Delta Smelt. All of the actions will be in compliance with applicable laws, including the Federal Endangered Species Act, California Endangered Species Act, California Environmental Quality Act, National Environmental Policy Act, and the Federal Clean Water Act. The Collaborative Science and Adaptive Management Program (CSAMP) will be used to determine the appropriate research approach to designing and assessing the outcomes of these management actions individually and synergistically. Additionally, it is expected that the Bureau of Reclamation (Reclamation) would participate in the implementation of this Strategy, including providing enhanced outflows in 2016.

Delta Vision Strategic Plan

State of California | October 17th, 2008

When it was created by Governor Schwarzenegger’s Executive Order S-17-06 in 2006, the charge of the Delta Vision Blue Ribbon Task Force (Task Force) was nothing less th

When it was created by Governor Schwarzenegger’s Executive Order S-17-06 in 2006, the charge of the Delta Vision Blue Ribbon Task Force (Task Force) was nothing less than to create a vision to repair the ecological damage to the Sacramento-San Joaquin River Delta (Delta), and then prepare a strategic plan which would sustain the Delta in future decades while ensuring a reliable water supply for the two-thirds of California’s population who depend in whole or in part on water from the Delta.

Delta Vision Strategic Plan -- from Phil Isenberg, 1939-2023

State of California | October 17th, 2008

When it was created by Governor Schwarzenegger’s Executive Order S-17-06 in 2006, the charge of the Delta Vision Blue Ribbon Task Force (Task Force) was nothing less th

When it was created by Governor Schwarzenegger’s Executive Order S-17-06 in 2006, the charge of the Delta Vision Blue Ribbon Task Force (Task Force) was nothing less than to create a vision to repair the ecological damage to the Sacramento-San Joaquin River Delta (Delta), and then prepare a strategic plan which would sustain the Delta in future decades while ensuring a reliable water supply for the two-thirds of California’s population who depend in whole or in part on water from the Delta.

Delta-Estuary California's Inland Coast A Public Trust Report

California State Lands Commission (SLC) | May 1st, 1991

Delta-Mendota Subbasin Staff Assessment

California State Water Resources Control Board (SWRCB) | March 2nd, 2026

The Delta-Mendota Subbasin (subbasin) is located in the western portion of the San Joaquin Valley, in portions of Fresno, Madera, Merced, San Joaquin, San Benito, and Sta

The Delta-Mendota Subbasin (subbasin) is located in the western portion of the San Joaquin Valley, in portions of Fresno, Madera, Merced, San Joaquin, San Benito, and Stanislaus counties, and contains the cities of Dos Palos, Firebaugh, Gustine, Los Banos, Mendota, Newman, and Patterson. It is critically overdrafted and managed by 7 GSA Groups, comprised of 23 GSAs, which include: the Aliso Water District GSA Group, the Farmers Water District GSA Group, the Fresno County Management Areas A and B GSA Group, the Grassland GSA Group, the Northern Delta-Mendota GSA Group, the Central Delta-Mendota GSA Group, and the San Joaquin River Exchange Contractors GSA Group. During most years, agriculture accounts for more than 85% of groundwater use in the subbasin (Water Year 2019–Water Year 2024 Annual Reports). The state intervention process for the Delta-Mendota Subbasin was initiated in March 2023 when DWR determined the subbasin’s six 2022 GSPs were inadequate.  The GSAs released a single revised draft GSP in May 2024, which they adopted with slight revisions in July 2024 (2024 GSP). State Water Board staff evaluated the 2024 GSP to determine if identified deficiencies were resolved. The GSAs made significant progress. State Water Board staff concludes the GSAs amended the GSP such that a probationary designation of the Delta-Mendota Subbasin is unnecessary and recommends the Board return the subbasin to DWR’s jurisdiction for continued evaluation of local management under SGMA.

Department of the Interior Nature-Based Solutions Roadmap

Nicholas Institute for Energy, Environment & Sustainability (Duke University) | December 1st, 2023

Design Life Level: Quantifying risk in a changing climate

American Geophysical Union (AGU) | September 23rd, 2013

In the past, the concepts of return levels and return periods have been standard and important tools for engineering design. However, these concepts are based on theassu

In the past, the concepts of return levels and return periods have been standard and important tools for engineering design. However, these concepts are based on theassumption of a stationary climate and do not apply to a changing climate, whether local orglobal. In this paper, we propose a refined concept, Design Life Level, which quantifies risk in a nonstationary climate and can serve as the basis for communication. In current practice, typical hydrologic risk management focuses on a standard (e.g., in terms of a high quantile corresponding to the specified probability of failure for a single year). Nevertheless, the basic information needed for engineering design should consist of (i) the design life period (e.g., the next 50 years, say 2015–2064); and (ii) the probability (e.g., 5% chance) of a hazardous event (typically, in the form of the hydrologic variable exceeding a high level) occurring during the design life period. Capturing both of these design characteristics, the Design Life Level is defined as an upper quantile (e.g., 5%) of the distribution of the maximum value of the hydrologic variable (e.g., water level) over the design life period. We relate this concept and variants of it to existing literature and illustrate how they, and some useful complementary plots, may be computed and used. One practically important consideration concerns quantifying the statistical uncertainty in estimating a high quantile under nonstationarity.