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  • Title

    Delta Regional Monitoring Program Mercury Monitoring

    Lead Delta Regional Monitoring Program [RMP]
    Description Monitoring of sport fish and water was conducted by the Delta Regional Monitoring Program (Delta RMP) from August 2016 to April 2017 to begin to address the highest priority information needs related to implementation of the Sacramento–San Joaquin Delta Estuary Total Maximum Daily Load (TMDL) for Methylmercury (Wood et al. 2010). Two species of sport fish, largemouth bass (Micropterus salmoides) and spotted bass (Micropterus punctulatus), were collected at six sampling locations in August and September 2016. The length-adjusted (350 mm) mean methylmercury (measured as total mercury, which is a routinely used proxy for methylmercury in predator fish) concentration in bass ranged from 0.15 mg/kg or parts per million (ppm) wet weight at Little Potato Slough to 0.61 ppm at the Sacramento River at Freeport. Water samples were collected on four occasions from August 2016 through April 2017. Concentrations of methylmercury in unfiltered water ranged from 0.021 to 0.22 ng/L or parts per trillion. Concentrations of total mercury in unfiltered water ranged from 0.91 to 13 ng/L. Over 99% of the lab results for this project met the requirements of the Delta RMP Quality Assurance Program Plan, and all data were reportable. This data report presents the methods and results for the first year of monitoring. Historic data from the same or nearby monitoring stations from 1998 to 2011 are also presented to provide context. Monitoring results for both sport fish and water were generally comparable to historic observations. For the next several years, annual monitoring of sport fish will be conducted to firmly establish baseline concentrations and interannual variation in support of monitoring of long-term trends as an essential performance measure for the TMDL. Monitoring of water will solidify the linkage analysis (the quantitative relationship between methylmercury in water and methylmercury in sport fish) in the TMDL. Water monitoring will also provide data that will be useful in verifying patterns and trends predicted by numerical models of mercury transport and cycling being developed for the Delta and Yolo Bypass by the California Department of Water Resources (DWR).
    Science topics Biosentinels, Fish, Methylmercury, Restoration, Water
    Updated November 17, 2022
  • Title

    Do light, nutrient, and salinity interactions drive the “bad Suisun” phenomenon? A physiological assessment of biological hotspots in the San Francisco Bay-Delta

    Lead University of California - Santa Cruz [UCSC]
    Description This project assessed the physiological basis for reduced phytoplankton growth in Suisun Bay, prior to the major upgrade at the Sacramento Regional Wastewater Treatment Plant (SRWTP), which is responsible for 90% of the nitrogen released into the bay. The work involved analyzing almost three decades of historical eld data from the bay-delta and using it to build a model to evaluate environmental drivers of phytoplankton biomass. Discoveries from the eld data were then tested through laboratory culturing experiments. By illuminating the interacting e ects of bottom- up drivers (light, nutrients, salinity) on phytoplankton, this research helps provide a fundamental understanding of this complex ecosystem.
    Science topics Ammonia, Flushing rates, Light, Open water, Pelagic fish, Phytoplankton, Salinity, Wastewater discharge, Water temperature
    Updated November 17, 2022
  • Title

    Operation Baseline Project 1: Conceptual Framework

    Lead Delta Stewardship Council
    Description A multidisciplinary team will develop a thorough conceptual model that will describe current conditions and consider changes from the WWTP upgrade. The model will be used to identify the highest priority science questions and investigations to pursue before, during, and after the plant upgrade.
    Science topics Algae, Floating aquatic vegetation, Food webs, Nitrogen / ammonia, Open water, Other discharge contaminants, Phytoplankton, Submerged aquatic vegetation, Wastewater discharge, Water operations / exports, Wetlands, Zooplankton
    Updated December 14, 2022
  • Title

    Assessing Sediment Nutrient Storage and Release in the Delta: Linking Benthic Nutrient Cycling to Restoration, Aquatic Vegetation, Phytoplankton Productivity, and Harmful Algal Blooms

    Lead U.S. Geological Survey [USGS]
    Description Nutrients in sediment play a large role in influencing food webs, harmful algal blooms, aquatic vegetation, and drinking water quality. This study will investigate the amount, types, and dynamics of nutrients in Delta sediments. It will also examine sediment microbial communities that mediate these processes. Results of this study will help determine how the planned reduction in nutrient inputs to the Delta will effect sediment nutrients and microbial communities following the upgrade of the Sacramento Regional County Sanitation District’s wastewater treatment plant. Data will also inform how wetland restoration and invasive aquatic vegetation influence sediment nutrients and microbial communities. These data will contribute to improving computer models that inform large-scale nutrient management actions.
    Science topics Aquatic vegetation, Benthic, Cyanobacteria, Harmful algal blooms HAB, Nitrogen, Nitrogen / ammonia, Nutrients, Phytoplankton, Sediments
    Updated May 14, 2024
  • Title

    Pesticide risk analyses and management actions, chemical fate and transport

    Lead University of California - Santa Barbara [UCSB]
    Description

    This project work will model the risk of pesticide pollution in 225 sub-catchments of the Sacramento-San Joaquin Bay-Delta. The model will account for water management practices, land use, pesticide use rates, and cumulative pesticide stress. Additionally, this work will produce a web-based tool to simulate current and future risks based on the ranking of primary sources of pesticide contribution. This work will provide a framework to predict risk from chemical stressors. Specific objectives are: (1) enhanced pro-active chemical risk assessment, (2) creation of a tool which enables science-based chemical use decisions, (3) improved risk screening for vulnerable areas, and (4) identification of adverse effects of current and future chemical use strategies.
    Science topics Herbicides
    Updated February 27, 2025
  • Title

    Nitrogen cycling and ecosystem metabolism before and after regulatory action

    Lead Stanford University
    Description

    This project focuses on nitrogen and carbon cycling within the Bay-Delta, both before and after planned 2021 upgrades to the Sacramento Regional Wastewater Treatment Plant (SRWTP). We will measure in situ benthic nitrate (NO3- ) and oxygen (O2) fluxes using a new non-invasive technique, which provides high frequency continuous data over a much larger sediment surface area than traditional methods. The SRTWP currently represents one of the largest point sources of nitrogen to the Bay-Delta, with the upgrades projected to cut nitrogen outputs from the plant by ~65%. This project will help assess the efficacy of this major management action and our results will add to biogeochemical models for the Bay-Delta.
    Science topics Nitrogen / ammonia
    Updated February 27, 2025
  • Title

    San Francisco Bay Joint Venture

    Lead U.S. Fish and Wildlife Service [USFWS]
    Description The San Francisco Bay Joint Venture (SFBJV) brings together over one hundred environmental organizations, governmental agencies, landowners, and the business community to achieve a common goal and vision: protect, restore and enhance wetlands throughout the nine Bay Area counties, for the benefit of wildlife and people. The San Francisco Bay Joint Venture (SFBJV) is one of twenty-two habitat-based Migratory Bird Joint Ventures (JV) that cover nearly all of the U.S. and Canada and much of Mexico. The SFBJV coordinates strategic habitat conservation throughout the nine San Francisco (SF) Bay Area counties in accordance with the SFBJV Implementation Plan. SFBJV partners work to protect, restore and enhance habitats through project implementation and by advancing related science, policy and communication priorities. The Joint Venture program provides opportunities to develop and deliver creative solutions to our current conservation challenges through the power of collaboration and partnership. The SFBJV is funded by the U.S. Fish and Wildlife Service (USFWS) and grants from other partners and programs.
    Science topics Hunting, Agriculture, Urban development, Recreation & tourism, Surface water / flow, Flood, Mudflats, Intertidal / transition zones, Above-highwater refugia, Main channels, Sloughs, Backwater, Submerged aquatic vegetation, Floating aquatic vegetation, Seasonally flooded, Open water, Managed ponds, Riparian wildlife, Delta islands, Pacific flyway, Waterfowl, Shorebirds, Gulls, Saltwater / freshwater marshes, Habitat, Non-resident / overwintering birds
    Updated April 29, 2022
  • Title

    Water Quality Data for California

    Lead U.S. Geological Survey [USGS]
    Description The USGS collects and analyzes chemical, physical, and biological properties of water, sediment and tissue samples from across the Nation. The Water Data for the Nation discrete sample data base is a compilation of over 4.4 million historical water quality analyses in the USGS district data bases through September 2005. The discrete sample data is a large and complex set of data that has been collected by a variety of projects ranging from national programs to studies in small watersheds.
    Science topics Water temperature, Dissolved oxygen, pH, Conductivity
    Updated April 29, 2022
  • Title

    Grasslands Bypass Project Monitoring

    Lead U.S. Bureau of Reclamation [USBR]
    Description The Grassland Bypass Project has been under waste discharge requirements (WDRs) since 1998. Historically, subsurface agricultural drainage water (tile drainage) and surface runoff (irrigation tail water) from the Grassland Watershed was discharged to the San Joaquin River through Salt Slough and/or Mud Slough (north). These two sloughs are tributary to the San Joaquin River and serve as the primary drainage outlets for the Grassland Watershed. With the start of the Grassland Bypass Project in 1996, all tile drainage from a 97,000 acre area known as the Grassland Drainage Area is consolidated and conveyed through San Luis Drain to Mud Slough, eliminating discharges of drainage water from the Grassland Drainage Area into Salt Slough and wetlands. Reducing selenium in wetland channels is the primary goal of the Project, as elevated concentrations of selenium have been documented to be hazardous to wildlife. The Project prevents discharge of subsurface agricultural drainage water into wildlife refuges and wetlands in central California . The drainage water is conveyed instead through a segment of the San Luis Drain to Mud Slough, a tributary of the San Joaquin River. The Project improves water quality in the wildlife refuges and wetlands, sustains the productivity of 97,000 acres of farmland, and fosters cooperation between area farmers and regulatory agencies in drainage management reduction of selenium and salt loading. The Project is operated by the Bureau of Reclamation and the San Luis & Delta-Mendota Water Authority (Authority).
    Science topics Agriculture, Surface water / flow, Water temperature, pH, Selenium, Conductivity
    Updated April 29, 2022
  • Title

    Bioaccumulation Monitoring Program

    Lead San Francisco Estuary Institute [SFEI]
    Description The Bioaccumulation Oversight Group (BOG) is a subcommittee of the SWAMP Roundtable that provides oversight of SWAMP's statewide bioaccumulation monitoring program. The BOG is also a workgroup of the California Water Quality Monitoring Council, and in this role manages the Safe to Eat Portal and is a forum for coordination of bioaccumulation monitoring in California. The mission of the BOG is to assess the impacts of contaminants in fish and shellfish on beneficial uses in California water bodies through statewide monitoring under SWAMP and perform syntheses of information from other studies, and to develop an internet portal that presents this information to decision-makers and the public in a form that they can easily use. See the Workgroup Charter for more information.
    Science topics Fishing, Main channels, Sloughs, Backwater, Chinook Salmon, Steelhead Trout, Pelagic fish, Striped bass
    Updated April 29, 2022
  • Title

    California Aquatic Resource Inventory [CARI]

    Lead San Francisco Estuary Institute [SFEI]
    Description The California Aquatic Resource Inventory is a standardized statewide map of surface waters and related habitat types, including wetlands, rivers, streams, lakes, and their riparian areas. The CARI v0 dataset includes: the National Wetland Inventory (NWI, last updated in 2010) of the US Fish and Wildlife Service, the National Hydrography Dataset (NHD, high resolution dataset at 1:2400 scale, last updated in 1999) of the US Geological Survey, three regional datasets developed by SFEI's GIS team using CARI's standardized, and more detailed, mapping protocols and used to demonstrate the WRAMP framework. Links to more information about these mapping efforts are listed below under "Subprojects" (below). San Francisco Bay Area Aquatic Resources Inventory (BAARI)- 2011 Lake Tahoe Basin (TARIv2.1) - 2016 Laguna de Santa Rosa Plain (near Santa Rosa ,CA. NCARI) - 2013, and Six County Aquatic Resources Inventory (including Sacramento, Placer, Yolo, El Dorado, Yuba, and Sutter Counties, California) developed by the US Army Corps of Engineers (Sacramento District) through federal funding - 2010. For more information contact ecoatlas@sfei.org
    Science topics Mudflats, Intertidal / transition zones, Above-highwater refugia, Saltwater / freshwater marshes
    Updated April 29, 2022
  • Title

    Water Quality of San Francisco Bay

    Lead U.S. Geological Survey [USGS]
    Description This website provides information about the following components of water quality: salinity, temperature, suspended particulate matter, dissolved oxygen, light penetration, and chlorophyll concentration. These parameters are measured using a submersible instrument package called a CTD. This program complements the Interagency Ecological Program (IEP) for the San Francisco Bay/Delta Ecosystem.
    Science topics Solar irradiance, Chlorophyll A / B, Suspended sediment, Salinity, Water temperature, Dissolved oxygen, Other discharge contaminants, Main channels
    Updated April 29, 2022
  • Title

    Regional Monitoring Program for Water Quality in San Francisco Bay

    Lead U.S. Geological Survey [USGS]
    Description The Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) is SFEI's largest program. It provides the information that regulators and decision-makers need to manage the Bay effectively. The RMP is an innovative collaborative effort between SFEI, the Regional Water Quality Control Board, and the regulated discharger community.
    Science topics Stage, Solar irradiance, Nitrogen / ammonia, Phosphorous, Carbon, Chlorophyll A / B, Suspended sediment, Salinity, Water temperature, Dissolved oxygen, Turbidity, Hg and methyl mercury, Copper, Selenium, Other discharge contaminants, Main channels, Conductivity, Habitat
    Updated April 29, 2022