San Francisco Bay

Delta Landscapes Executive Summary

San Francisco Estuary Institute (SFEI) | December 1st, 2017

The Sacramento-San Joaquin Delta supplies freshwater to a large portion of California’s cities and agriculture, supports an agricultural economy and culture, and is hom

The Sacramento-San Joaquin Delta supplies freshwater to a large portion of California’s cities and agriculture, supports an agricultural economy and culture, and is home to native wildlife found nowhere else in the world. This complex region is hampered by many environmental challenges, including an over-allocated water supply, invasive species, water quality problems, novel ecosystems that no longer support desired functions, aging infrastructure, and a complex management structure. Beyond these challenges, sea level rise, other impacts from climate change, and earthquakes pose significant risks to Delta ecosystems, agriculture and water supply. There is general consensus that ecosystem restoration and planning for future resilience needs to take place, within the context of the Delta’s unique culture and economy. Imagining a healthy Delta ecosystem in the future and taking bold, concrete steps toward that future requires an understanding and vision of what that healthy ecosystem could look like. For a place as extensive, unique, and modified as the Delta, critical knowledge can be acquired through the study of the past, investigating the Delta as it existed just prior to the substantial human modifications of the past two centuries. Though the Delta is irrevocably altered, its history is still relevant. Underlying geologic and hydrologic processes still influence the landscape. Native species adapted to live in the historical ecosystems, so restoring functional landscapes that reflect historical patterns can increase the success of restoration efforts.  The Delta Landscapes project investigates the historical ecosystems of the Delta and how they have been modified in the current landscape in order to produce a holistic, aspirational approach to restoration of desired ecological functions. The project goes beyond immediate planning horizons and mandated protection of particular species to explore how restoration of large-scale processes of sediment and water could drive a broad suite of ecological benefits. Restoration or emulation of such processes requires large areas and long time scales. The Delta Landscapes project produced three reports, summarized here, that speak to the past, present, and potential future Delta. The final report, A Delta Renewed, provides a framework for how individual projects planned in the near-term can contribute to a coherent, long-term vision of improving ecosystem function across the Delta. The purpose of this planning framework is to foster more effective and economical restoration of desired functions in a smaller footprint, because each project is contributing to improving a larger system, than could be achieved by projects planned in isolation that each focus on more narrow, varied benefits. The project is purposefully conceived to address only ecological benefits, in the context of a working agricultural landscape with critical water-supply and cultural considerations. The reports can contribute to discussions where social and economic benefits are also evaluated in planning the future Delta landscape. A Delta Renewed User Guide was developed to help different audiences access the information in this report and apply it effectively.  This research was conducted at the request of the California Department of Fish and Game (CDFG) and the Ecosystem Restoration Program (ERP). 

Delta Landscapes: A Delta Renewed User Guide

San Francisco Estuary Institute (SFEI) | December 1st, 2017

A Delta Renewed User Guide aims to increase the accessibility of the technical findings in A Delta Renewed for easier application to restoration and conservation efforts

A Delta Renewed User Guide aims to increase the accessibility of the technical findings in A Delta Renewed for easier application to restoration and conservation efforts across the Delta. The recommendations in A Delta Renewed focus on landscape-scale ecological guidance. We present three examples of how the information in A Delta Renewed might be used to address different management and restoration questions. Because of the complexity of the Delta system, this guide does not address all possible questions and does not replace the need for detailed, site-specific data and expertise. Rather, it shows how the information in A Delta Renewed might provide a common foundation for restoration planning.  The User Guide was written for a broad audience, including restoration practitioners, landowners, and local, state and federal agencies. The guide provides a step-by-step path through A Delta Renewed; a user is walked through how to apply the findings of the report via a series of steps to address each of the three restoration and management questions. This process is intended to help the user access regionally-specific recommendations and strategies to plan and manage future Delta landscapes that can support desired ecological functions over the long term.  The goal of A Delta Renewed and this guide is not to recreate the Delta of the past. Rather, the objective is to understand how we can re-establish or mimic important natural processes and patterns within this altered system to support desirable ecological functions (such as healthy native fish populations, a productive food web, and support for endangered species), now and into the future. 

Delta Levee Investment Strategy: Final Report

Delta Stewardship Council (Delta Council) | August 4th, 2017

In the California Sacramento-San Joaquin Delta (Delta), levee failure could cause catastrophic flooding, potentially causing injury or loss of life, and possibly damaging

In the California Sacramento-San Joaquin Delta (Delta), levee failure could cause catastrophic flooding, potentially causing injury or loss of life, and possibly damaging property, water supply, infrastructure, and environmental resources of importance to the entire State of California (State). Though levee maintenance and improvements over the past three decades have reduced the frequency of levee failures, the State has no comprehensive method to prioritize its investments in Delta levees operations, maintenance, and improvement projects. The Delta Plan, adopted on May 16, 2013, recommends that the Delta Stewardship Council (Council), in consultation with the California Department of Water Resources (DWR), the Central Valley Flood Protection Board (CVFPB), the Delta Protection Commission (DPC), local agencies, and the California Water Commission, implement California Water Code (CWC) section 85306 by developing a Delta Levees Investment Strategy (DLIS) to identify funding priorities for State investments in Delta levees. The DLIS is an innovative approach for determining priorities for State funds for levee improvement in the Delta and Suisun Marsh. The DLIS, which considers the assets protected by levees, the threats to levees, and the multiple beneficiaries of levee investments, uses a risk analysis methodology to recommend priorities for State investments in levee operations, maintenance, and improvements. This methodology was developed in close coordination with State agency partners, local and regional flood management and emergency response planning agencies, and other interested parties. In total, the Council worked with 113 different stakeholders and conducted 10 public meetings, 60 stakeholder outreach meetings, and 60 interagency coordination meetings. The Council also discussed DLIS issues at 38 Council meetings and workshops, which provided opportunities for public comment. The DLIS team developed a Decision Support Tool (DST) to enable the Council and stakeholders to review and update the data and analysis that form the basis of the risk evaluation. The DST supports deliberations by summarizing information about baseline and future risks, aggregating and displaying risks, and then identifying portfolios of investments that have the potential to reduce risk to State interests. The data components in the DST are designed to be updated as new information is collected or identified.

Delta Levees – Types, Uses, and Policy Options

Delta Vision Blue Ribbon Task Force (Delta Vision) | August 7th, 2008

This document was developed to support Delta Vision discussions on the role of levees in the Delta’s future. It is to clarify the different types (or design standards)

This document was developed to support Delta Vision discussions on the role of levees in the Delta’s future. It is to clarify the different types (or design standards) of levees that now exist for the Delta and what improvements could be considered. It is especially oriented toward an improved understanding of what types of levees are suitable for protecting various land uses or for other applications. Based on understanding the levee types, policy options are identified for a) selecting levee improvements to be included in the vision of the Delta’s future and b) implementing the improvements selected.

Delta Narratives: Saving the Historical and Cultural Heritage of the Sacramento-San Joaquin Delta

Delta Protection Commission (DPC) | August 1st, 2015

From August 2014 through July 2015, the Delta Narratives project, on contract to the Delta Protection Commission, addressed two questions. First, in what ways does the hi

From August 2014 through July 2015, the Delta Narratives project, on contract to the Delta Protection Commission, addressed two questions. First, in what ways does the historical experience of the Sacramento-San Joaquin Delta contribute to an understanding of key themes in regional and American history? Second, how might Delta stories gain wider appreciation within the region, throughout Northern California, and among people in the rest of California and beyond? Scholars on the project team documented ways the history of the Delta illustrates trends in land management and reclamation, technological shifts in transportation and agriculture, the impact of ethnicity and labor specialization on community building, and finally, the shifting visioning of America's promise and fall from grace by artists and writers in response to the intense cultivation of the Delta and the conditions which workers there endured. Their essays testify to the intrinsic value of Delta stories and to the additional perspectives they bring to regional and national history. With these essays in hand, the project team investigated the current infrastructure for the preservation and dissemination of historical and cultural information in the Delta. It created a directory of institutions committed to promoting Delta stories. In order to stimulate conversations between these stakeholders, the team organized two workshops at which the scholars and archivists shared insights and invited commentary and conversation. Subsequently, with the support of the Center for California Studies at Sacramento State University, a conference entitled “More than H2O: Saving the History and Culture of the Sacramento-San Joaquin Delta” presented findings and discussed strategies with an audience of state and local stakeholders. Delta Narratives culminated with a conference organized around an American Assembly model. The conference generated a list of suggestions for further action regarding the recognition, preservation, and dissemination of Delta stories. High on the list of initiatives were adequate mapping of historically significant locations, an organization that would draw together the many cultural and historical groups in the Delta toward common action, the initiation of annual Delta Days to celebrate the region, and the creation of educational materials including web applications (apps), and a website devoted to the region.

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 Regional Monitoring Program Annual Monitoring Report for Fiscal Year 2015–16: Pesticides and Toxicity

San Francisco Estuary Institute (SFEI) | March 1st, 2018

The primary purpose of this report is to document the first year (FY15/16) of pesticide monitoring by the Delta Regional Monitoring Program (Delta RMP). This document rep

The primary purpose of this report is to document the first year (FY15/16) of pesticide monitoring by the Delta Regional Monitoring Program (Delta RMP). This document reports the results from samples collected monthly from July 2015 through June 2016. The data described in this report are available for download via the California Environmental Data Exchange Network (CEDEN) website. Pesticide monitoring of the Delta RMP includes chemical analysis and toxicity testing of surface water samples. The parameters analyzed include 154 current use pesticides, dissolved copper, field parameters, and “conventional” parameters (ancillary parameters measured in the laboratory, such as dissolved/particulate organic carbon and hardness). Toxicity tests included an algal species (Selenastrum capricornutum, also known as Raphidocelis subcapitata), an invertebrate (Ceriodaphnia dubia, a daphnid or water flea), and a fish species (Pimephales promelas, fathead minnow). Toxicity testing included the evaluation of acute (survival) and chronic (growth, reproduction, biomass) toxicity endpoints. The surface water samples were collected from 5 fixed sites representing key inflows to the Delta that were visited monthly: Mokelumne River at New Hope Road, Sacramento River at Hood, San Joaquin River at Buckley Cove, San Joaquin River at Vernalis, and Ulatis Creek at Brown Road. A total of 52 pesticides were detected above method detection limits (MDLs) in water samples (19 fungicides, 17 herbicides, 9 insecticides, 6 degradates, and 1 synergist). A total of 9 pesticides (5 herbicides, 3 insecticides, and 1 degradate) were detected in suspended sediments in 10 of a total of 60 samples collected during the study period. All collected samples contained mixtures of pesticides ranging from 2 to 26 pesticides per sample. From a total of 154 target parameters, 100 compounds were never detected in any of the samples.

Delta Regional Monitoring Program Nutrients Synthesis: Modeling to Assist Identification of Temporal and Spatial Data Gaps for Nutrient Monitoring

San Francisco Estuary Institute (SFEI) | March 1st, 2018

Nutrient loads are an important water quality management issue in the Sacramento-San Joaquin Delta (Delta) and there is consensus that the current monitoring activities d

Nutrient loads are an important water quality management issue in the Sacramento-San Joaquin Delta (Delta) and there is consensus that the current monitoring activities do not collect all the information needed to answer important management questions.  The purpose of this report is to use hydrodynamic model outputs to refine recommendations for monitoring nutrients and related conditions in the Delta. The basic premise was that variability in water source and hydraulic residence time can serve to estimate variability in water quality. Therefore, using existing hydrodynamic models that are highly resolved in space and time could be a cost-effective way to get information about likely spatial and temporal variability in nutrients and nutrient-associated parameters. We assume that the Delta can be divided into relatively homogeneous subregions (e.g., such as those proposed in a previous report by Jabusch et al. 2016) and that a representative monitoring location can be chosen in each subregion to track status and trends. We also assume that, within any subregion, areas with long hydraulic residence time and source water mixing may represent potential nutrient transformation hotspots.  Two types of modeling approaches were applied: 1) volumetric water source analysis to evaluate the mix of source waters within each subregion; and 2) particle tracking simulations. Results from the source water analysis were evaluated to assess heterogeneity of water sources within each of the subregions. Results from the particle tracking analysis were evaluated to identify high-residence-time areas. Finally, we compared analysis results to current monitoring locations to inform potential monitoring gaps or redundancies within each of the subregions. 

Delta Salinity Management Workshops 2022 Information Sheet

Delta Stewardship Council (Delta Council) | March 7th, 2022