Priority Margin Unit Stormwater Monitoring to Support Load Estimates of PCBs into San Leandro Bay and the Emeryville Crescent

San Francisco Estuary Institute (SFEI) | July 15th, 2022

The Priority Margin Unit Studies: The 2014 update of the RMP PCB Strategy called for a multi-year effort to implement the recommendations of the  PCB Synthesis Report (D

The Priority Margin Unit Studies: The 2014 update of the RMP PCB Strategy called for a multi-year effort to implement the recommendations of the  PCB Synthesis Report (Davis et al., 2014) including: 1. identifying margin units that are high priorities for management and monitoring, 2. developing conceptual models and mass budgets for margin units downstream of watersheds where management actions will occur, and 3. monitoring in these units as a performance measure. The goal of the effort was to inform the review and possible revision of the PCB TMDL and the reissuance of the Municipal Regional Permit for Stormwater (MRP).

Productive wetlands restored for carbon sequestration quickly become net CO2 sinks with site-level factors driving uptake variability

PLOS | March 25th, 2021

Inundated wetlands can potentially sequester substantial amounts of soil carbon (C) over the long-term because of slow decomposition and high primary productivity, partic

Inundated wetlands can potentially sequester substantial amounts of soil carbon (C) over the long-term because of slow decomposition and high primary productivity, particularly in climates with long growing seasons. Restoring such wetlands may provide one of several effective negative emission technologies to remove atmospheric CO2 and mitigate climate change. However, there remains considerable uncertainty whether these heterogeneous ecotones are consistent net C sinks and to what degree restoration and management methods affect C sequestration. Since wetland C dynamics are largely driven by climate, it is difficult to draw comparisons across regions. With many restored wetlands having different functional outcomes, we need to better understand the importance of site-specific conditions and how they change over time. We report on 21 site-years of C fluxes using eddy covariance measurements from five restored fresh to brackish wetlands in a Mediterranean climate. The wetlands ranged from 3 to 23 years after restoration and showed that several factors related to restoration methods and site conditions altered the magnitude of C sequestration by affecting vegetation cover and structure. Vegetation established within two years of re-flooding but followed different trajectories depending on design aspects, such as bathymetry-determined water levels, planting methods, and soil nutrients. A minimum of 55% vegetation cover was needed to become a net C sink, which most wetlands achieved once vegetation was established. Established wetlands had a high C sequestration efficiency (i.e. the ratio of net to gross ecosystem productivity) comparable to upland ecosystems but varied between years undergoing boom-bust growth cycles and C uptake strength was susceptible to disturbance events. We highlight the large C sequestration potential of productive inundated marshes, aided by restoration design and management targeted to maximise vegetation extent and minimise disturbance. These findings have important implications for wetland restoration, policy, and management practitioners.

Property Prices in Peril

First Street | February 3rd, 2025

Regional desirability is being reshaped by chronic changes in climate across the country: coastal areas are increasingly threatened by sea level rise, while inland region

Regional desirability is being reshaped by chronic changes in climate across the country: coastal areas are increasingly threatened by sea level rise, while inland regions face intensifying heat waves, droughts, and floods. At the same time, the increased frequency and intensity of natural disasters has triggered unprecedented levels of property damage, prompting insurance providers to increase premiums or withdraw coverage from high-risk areas altogether. Chronic climate changes create additional financial burdens – from surging utility bills to increased maintenance costs. Ultimately, environmental stressors and associated rising homeownership costs are together reshaping home values. With residential real estate representing one of the largest economic sectors in the country, these shifts will result in serious impacts that ripple through communities. Understanding these dynamics is crucial as public and private stakeholders navigate an increasingly complex landscape where housing decisions must balance traditional location value drivers with new climate realities.

Proposal for a Revised ITL and Expected Take for Adult Delta Smelt

Delta Stewardship Council (Delta Council) | July 29th, 2014

The 2008 USFWS Incidental Take Level (ITL) calculation determines the amount of annual delta smelt salvage allowed to be taken by the State Water Project (SWP) an

The 2008 USFWS Incidental Take Level (ITL) calculation determines the amount of annual delta smelt salvage allowed to be taken by the State Water Project (SWP) and Central Valley Project (CVP) during operating conditions expected under Reasonable and Prudent Alternative (RPA) thresholds. There is an ITL for adult and juvenile delta smelt. Using advances in statistical models, data sources, and overall improved knowledge of entrainment dynamics, we offer a robust approach for calculating a revised ITL and accompanying expected take method under the RPA for the SWP and CVP that remains protective of the species while providing improved flexibility for managing water operations.

Proposal for Calculating Cumulative Salvage Index Values Used For Estimating Take Likely to Occur under the USFWS Old and Middle River Flow RPA for Adult Delta Smelt

Delta Stewardship Council (Delta Council) | September 19th, 2014

The objectives of this paper are to provide a rationale why the United States Fish and Wildlife Service (USFWS) Incidental Take Statement should include more year

The objectives of this paper are to provide a rationale why the United States Fish and Wildlife Service (USFWS) Incidental Take Statement should include more years in its calculation of anticipated incidental take of adult delta smelt under the 2008 Biological Opinion with the Reasonable and Prudent Alternative (RPA) action to avoid jeopardy to the species and adverse modification of critical habitat and provide a statistical method by which this can be achieved.

Protocol for Closure of Delta Waterways

Office of Emergency Services | November 21st, 1997

This protocol describes the process for placing restrictions on vessel traffic on the San Joaquin/Sacramento Delta waterways during periods of high water levels and flood

This protocol describes the process for placing restrictions on vessel traffic on the San Joaquin/Sacramento Delta waterways during periods of high water levels and flood events that involve conditions of disaster or extreme peril to the safety of persons and property. Restrictions will provide for flood fight priorities and control of vessel wakes that may exacerbate levee erosion or overtopping.

Prototyping structured decision making for water resource management in the San Francisco Bay-Delta

Environmental Science & Policy (Elsevier) | May 2nd, 2024

A structured decision making (SDM) approach can help evaluate tradeoffs between conservation and human-benefit objectives by fostering communication and knowledge transfe

A structured decision making (SDM) approach can help evaluate tradeoffs between conservation and human-benefit objectives by fostering communication and knowledge transfer among stakeholders, decision makers, and the public. However, the process is iterative and completing the full process may take years. It can be difficult to initiate an SDM effort when problems seem insurmountable. Occasionally, SDM may not even be the best or correct approach for addressing the conservation problem at hand. We describe the implementation of an SDM process to help inform difficult decisions related to competing objectives. We convened a diverse stakeholder group from the largest estuary in the western United States; the San Francisco Bay and Sacramento-San Joaquin Delta (Bay-Delta). The stakeholder group consisted of representatives from local, state, and federal agencies, non-profit organizations, and recreational fishers. The stakeholder group agreed on a problem statement and identified four priority objectives related to Chinook salmon, delta smelt, water availability and reliability, and agricultural water use. Furthermore, they proposed 14 candidate management actions to achieve their objectives. The group then used existing quantitative models and data to evaluate trade-offs in proposed management actions to identify areas of agreement of proposed candidate actions. The clear communication of the problem statement and objectives among the stakeholder group, along with evaluation of tradeoffs and uncertainty via decision-support models suggest that a full SDM approach may work in the Bay-Delta. We further communicate lessons learned during our implementation of SDM to help guide future SDM efforts in the region and elsewhere. See also: Structured Decision Making Delta Stewardship Council June 2024 meeting report.

Pulse of the Delta 2011

San Francisco Estuary Institute (SFEI) | March 16th, 2011

Welcome to the first issue of the Pulse of the Delta: Monitoring and Managing Water Quality in the Sacramento – San Joaquin Delta, the new publication of the emerging D

Welcome to the first issue of the Pulse of the Delta: Monitoring and Managing Water Quality in the Sacramento – San Joaquin Delta, the new publication of the emerging Delta Regional Monitoring Program (RMP). This report is a direct response to Delta RMP stakeholders’ desire for an accessible water quality summary for the Delta that addresses important regional questions. Table of Contents: Did Contaminants Play a Role in the Pelagic Organism Decline? The Delta RMP: Re-thinking Water Quality Monitoring in the Delta Ammonia in the Delta: The science, implications for management How Delta Studies Have Reshaped Our Understanding Pyrethroid Insecticides Contaminants of Emerging Concern: Adapting to a Moving Target New Pesticides

Pulse of the Delta 2012

San Francisco Estuary Institute (SFEI) | August 2nd, 2013

This second edition of the Pulse of the Delta includes the following sections: The KEY TOPIC article introduces this year’s theme, LINKING SCIENCE AND MANAGEMENT THR

This second edition of the Pulse of the Delta includes the following sections: The KEY TOPIC article introduces this year’s theme, LINKING SCIENCE AND MANAGEMENT THROUGH REGIONAL MONITORING (PAGE 6). The MANAGEMENT UPDATE section provides updates on Delta RMP development (PAGE 12) and the U.S. Environmental Protection Agency (EPA)’s Delta Clean Water Act evaluation (PAGE 18). It further provides an update on the development of Nutrient Numeric Endpoints for San Francisco Bay, due to the relevance of this topic to Delta stakeholders (PAGE 28). And as a new feature, the Management Update section now also provides a regulatory status update for pollutants of concern. This edition of the Pulse of the Delta introduces a NEW STATUS AND TRENDS section with updates on important monitoring results (PAGE 44) and leading indicators (PAGE 50) for the Delta. The STATUS AND TRENDS section was made possible thanks to significant contributions by the Interagency Ecological Program, U.S. Geological Survey, the Central Valley Regional Water Board, California Department of Fish and Game, California Department of Water Resources, and scientists at the UC Berkeley and San Francisco State University Romberg Tiburon Center. Two FEATURE ARTICLES provide an overview of recent research findings that could help wetland managers reduce the methylmercury problem and a glimpse into the future of the Interagency Ecological Program (IEP). One of the main challenges as ecosystem restoration efforts are moving forward will be the mercury problem. Large-scale restoration of wetland areas will be required to provide a sufficient amount of aquatic habitat for restoring the Delta ecosystem. At the same time, water quality managers will need to identify actions to protect people and wildlife from exposure to methylmercury that may originate from restored wetlands, due to a legacy of mercury contamination in Delta soils. Recently completed and ongoing studies in the Yolo Bypass provide new information on management options for controlling methylmercury production in wetlands and offsite transport (PAGE 66). IEP scientists have been monitoring and researching the San Francisco Estuary since 1970. Now the IEP has arrived at an important crossroads, and its future is being decided at the same time as environmental managers are determining what a desirable future ecosystem would look like, how it would function, and how it can be established (PAGE 76).

Putting People over Fish: Stopping Radical Environmentalism to Provide Water to Southern California

The White House | January 20th, 2025