Small Tributaries Pollutants of Concern Reconnaissance Monitoring: Loads and Yields-based Prioritization Methodology Pilot Study

San Francisco Estuary Institute (SFEI) | October 1st, 2019

Watershed yields (mass exported per unit watershed area) can be used as an indicator variable to help identify watersheds or source areas of higher management interest i

Watershed yields (mass exported per unit watershed area) can be used as an indicator variable to help identify watersheds or source areas of higher management interest in relation to mass loads that impact the Bay. When prioritization includes an analysis of uncertainty, a recommendation can also be made for priority investigations necessary to reduce uncertainties. A method is presented for generating comparable yield estimates for small industrial watersheds where only a single storm has been sampled and for which a watershed boundary has been generated. The method generates standardized storm-based yields for each sampled site for a 0.5-year annual return frequency storm with 2-hour peak rainfall intensity. No attempt has been made to estimate annual average yields (the metric upon which the TMDL was based).

Small Tributaries Pollutants of Concern Reconnaissance Monitoring: Pilot Evaluation of Source Areas Using PCB Congener Data

San Francisco Estuary Institute (SFEI) | October 1st, 2019

PCB congener profiles can be used to help identify source areas that contribute most to the PCB mass exported from the watershed via stormwater and to illustrate variabi

PCB congener profiles can be used to help identify source areas that contribute most to the PCB mass exported from the watershed via stormwater and to illustrate variability in PCB mobilization from source areas over time. A method is presented for estimating the contributions of different Aroclor mixtures to the congener profiles of samples of stormwater and sediment. The method is based on the use of indicator congeners that are representative of each of the four most commonly used Aroclors. In this report, the method was applied in three watersheds. In the Pulgas Pump Station watershed, stormwater and sediment had high concentrations with a unique congener profile, dominated by congeners indicative of a combination of Aroclors 1242 and 1260. The concentrations and congener profiles in sediment suggest that there are two distinct source areas in the watershed that combine to create the mix of 1242 and 1260 that is dominant in stormwater at the Pump Station. The data indicate that if PCB flux from one of these areas could be eliminated, loads from the watershed would be reduced by 50% or more. For the Coyote Creek watershed, the similarity in congener profiles for the highest concentration sediment samples and the stormwater samples suggest that the important source areas in the watershed have been identified, and that reduction of loading from an area at the south end of the Charcot Avenue Storm Drain watershed would yield the greatest reduction in export at the Coyote Creek station. The concentrations and congener profiles in stormwater and sediment from the Guadalupe River watershed indicate the presence of one source area that is likely a substantial contributor to PCB export from the watershed, but that all of the significant sources areas may not yet have been identified.

Sniffing the Delta for Greenhouse Gases

San Francisco Estuary Partnership (SFEP) | June 16th, 2022

Global food production contributes an estimated 21% to 37% of the greenhouse gases that are warming the planet, including huge releases of carbon when vast aquatic ecosys

Global food production contributes an estimated 21% to 37% of the greenhouse gases that are warming the planet, including huge releases of carbon when vast aquatic ecosystems like the Delta are transformed for agriculture. [Dennis] Baldocchi and colleagues are now trying to figure out if bringing back tidal wetlands like the one at Dutch Slough can help reverse these processes.

So, You Want a Farm in Westlands Water District

University of California | August 2nd, 1976

State Investments in Delta Levees

Delta Stewardship Council (Delta Council) | January 1st, 2015

This 43-page Issue Paper, authored by Dustin Jones, the Council's Integrated Regional Water Management Supervising Engineer, is entitled State Investments in Delta Levees

This 43-page Issue Paper, authored by Dustin Jones, the Council's Integrated Regional Water Management Supervising Engineer, is entitled State Investments in Delta Levees, Key Issues for Updating Priorities. The Delta Reform Act requires that the Delta Plan promote strategic levee investments that attempt to reduce risks to people, property, and state interests in the Delta (Water Code section 85305) and recommend priorities for state investment in levee operation, maintenance, and improvements in the Delta (Water Code section 85306). In addition, the Delta Plan may identify actions to be taken outside of the Delta, if those actions are determined to significantly reduce flood risks in the Delta and may include local plans of flood protection (Water Code section 85307(a-b)). This paper outlines 15 issues that will need to be considered as the Council updates the Delta Plan’s provisions regarding State investment in the Delta’s levees. It summarizes background information about these issues, provides references for further information, and highlights key points to be addressed through the development of the Delta Levees Investment Strategy.

State Investments in Delta Levees: Key Issues For Updating Priorities

Delta Stewardship Council (Delta Council) | January 9th, 2015

This paper outlines 15 issues that will need to be considered as the Council updates the Delta Plan’s 36 provisions regarding State investment in the Delta’s levees.

This paper outlines 15 issues that will need to be considered as the Council updates the Delta Plan’s 36 provisions regarding State investment in the Delta’s levees. It summarizes background information 37 about these issues, provides references for further information, and highlights key points that will need 38 to be addressed over the coming months.

State of Bay Delta Science 2016: Introduction

University of California, Davis (UC Davis) | July 1st, 2016

The first edition of SBDS presented seven shifts in perspective or changes in the way that scientists understood the Delta and water supply that had emerged in the decade

The first edition of SBDS presented seven shifts in perspective or changes in the way that scientists understood the Delta and water supply that had emerged in the decade before its publication (Healey et al. 2008). These changes in scientific understanding have profoundly affected the long-term vision for the Delta and the way that it is managed (Delta Vision Task Force 2008; Delta Stewardship Council 2010). A similar evolution in understanding has emerged in the eight years since publication of the first edition of SBDS, and we expect our understanding of the Delta and California water will continue to evolve and change as new studies are conducted. SBDS will be a living document, updated from time to time as sufficient new findings accumulate and, in particular, as the effects of climate change become more apparent. Meeting the new and unprecedented challenges to water supply and ecosystem conservation that climate change will bring will require both an intensification of scientific effort and much better coordination and planning of Delta science. The papers that make up the second edition of SBDS represent one step toward an integrated and policy-relevant compilation of science in the Delta.

State of the Estuary 2019 Update

San Francisco Estuary Partnership (SFEP) | October 22nd, 2019

The San Francisco Estuary is a large and diverse system. Hundreds of miles of coastline stretch from the wide valleys of the Sacramento and San Joaquin Rivers to the stee

The San Francisco Estuary is a large and diverse system. Hundreds of miles of coastline stretch from the wide valleys of the Sacramento and San Joaquin Rivers to the steep headlands of the Golden Gate, with vast agricultural fields in the Delta and urbanized shorelines in Silicon Valley and many of the region’s cities. The complexity and scale of this system means it can take years to detect and assess changes. This interim State of the Estuary Report checks in on a few indicators of health and explores where the assessment should head over time. In the four years since the 2015 State of the Estuary Report, two issues have emerged as critical to how we assess the health of the estuarine ecosystem at the heart of the Bay Area and the Delta. First, the health of the Estuary and of the people who live near it and depend on it are inextricably linked. We need a healthy Bay and Delta to protect our shorelines from sea level rise, help keep our waters clean, provide food and habitat for fish and wildlife, and give people a place to enjoy nature. We also need to think more about human communities as we assess the health of natural communities. This focus means addressing environmental injustices that are deeply embedded in our culture and patterns of development. The second critical issue to emerge is the need for a greater focus on landscape resilience—how well the Bay and the Delta are equipped to respond to change—so that people and wildlife can thrive as climate change progresses. Taking these two ideas together, this report focuses on the nexus of social and ecological resilience as we look toward the future. The first section of the Report updates indicators of ecological health that span the entire extent of the San Francisco Estuary (Bay and Delta). Recent data show continued progress along the trajectories of the past decade. Tidal marsh restoration is proceeding at a brisk pace in the Bay and gaining traction in the Delta, while urban water conservation continues to meet mandated benchmarks, even during the drought. On the other hand, flows through the Estuary and across its floodplains continue to be well below levels that could increase and restore ecosystem health. Freshwater flows are a lynchpin of ecosystem processes that sustain physical habitats, fuel the food web, and regulate water quality. Creative approaches to using and re-using fresh water for environmental purposes are needed. Long-term trend analysis shows that fish communities in the Bay are declining. This analysis scores an index of 10 attributes of a healthy fish community. The index focuses on fish in offshore areas, and may not capture benefits to fish from near-shore wetland restoration projects. Despite this slow decline, fish communities in the saltier parts of the Estuary remain in good condition, while those in the brackish and freshwater areas are in poor condition. The next section of the report discusses three emerging indicators of Estuary health, offering options for how to assess resilience in future reports. Here, for the first time, the resilience of the Estuary’s shores is evaluated through the lens of subsidence and nature-based features. Elevation relative to sea level is a basic currency that must be tracked as the Pacific Ocean rises into the Estuary. The potential for the Estuary shore to be resilient to climate change and continue to provide benefits to people is related to how much of the shore zone is nature-based. The final emerging indicator, urban green space, is a first attempt to assess how access to nature is distributed across more and less advantaged communities. More work is needed to finalize all these emerging indicators before they can be included in any future quantitative assessment of the State of the Estuary. These emerging and updated indicators will help focus efforts to restore the Estuary’s health. In addition to continuing the successful aspects of restoration and conservation that this report describes, we need more investment in creative ways to use and restore flows for environmental health, to expand and build resilient shorelines and to weave considerations of social equity more strongly into efforts to improve environmental health. - J. Letitia Grenier, Lead Scientist

State of the Estuary, October 2013

San Francisco Estuary Partnership (SFEP) | October 31st, 2013

State Plan of Flood Control Descriptive Document (2010)

California Department of Water Resources (DWR) | January 15th, 2010

This report provides an inventory and description of the existing flood control works (facilities), lands, programs, plans, conditions, and mode of operations and mainten

This report provides an inventory and description of the existing flood control works (facilities), lands, programs, plans, conditions, and mode of operations and maintenance (O&M) for the State-Federal flood protection system in the Central Valley of California. This flood protection system is composed of federally authorized project levees and related facilities for which the State has provided assurances1 of cooperation to the federal government. These State-provided assurances are an important distinction for what constitutes the State-federal flood protection system since other flood protection facilities in the Central Valley are not covered by State assurances and are not part of the State-federal system. Collectively, the facilities, lands, programs, conditions, and mode of O&M for the State-Federal flood protection system in the Central Valley are referred to as the State Plan of Flood Control (SPFC). This SPFC Descriptive Document is the first time that an inventory of the SPFC has been compiled or referenced in a single document. Until now, much of the information on the SPFC has been individually maintained for each of the many flood protection projects that constitute State-federal flood protection along the Sacramento and San Joaquin rivers and tributaries. For example, much of the information contained in sections of this report originates in 118 individual project (unit-specific) O&M manuals. The O&M manuals provide key information about each project and how it should be operated and maintained (see reference digital versatile disc (DVD) at the back of this report). In addition, since the individual projects for the system were implemented over almost a century, some information may have been lost or never obtained. In those cases, gaps exist in the information presented in this report and further research is required. It is important to note that the SPFC is only a portion of the larger system that provides flood protection for the Central Valley. The SPFC relies on many other features that do not meet the definition of the SPFC. For example, non-SPFC reservoirs provide substantial regulation of flows to levels that SPFC facilities can mostly handle. Private levees, locally operated drainage systems, and other facilities work in conjunction with SPFC facilities. Management practices such as emergency response, floodplain management, and other practices are part of the overall flood protection system. All parts of the system, including the SPFC, depend on other parts of the system to operate as a unit. This report is structured as a reference document for the SPFC. It includes narrative descriptions, tables, and figures, especially maps, to help the reader find information for this complex flood management system. Some sections include summary sections for readers who only need an overview of the subject. RELATED DOCUMENT: State Plan of Flood Control Descriptive Document 2016 Update