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Records

  • Title

    Yolo Bypass Salmonid Habitat Restoration and Fish Passage

    Lead California Department of Water Resource [DWR]
    Description The Yolo Bypass Salmonid Habitat Restoration Project works to reconnect the floodplain for fish during the winter season and improve connectivity within the bypass and to the Sacramento River. The project provides seasonal inundation that mimics the natural process of the Yolo Bypass floodplain and improves connectivity within the bypass and to the Sacramento River.
    Science topics Chinook Salmon, Endangered species
    Updated April 29, 2022
  • Title

    Yolo Bypass Salmonid Habitat Restoration and Fish Passage: Scenario Analysis of Fremont Weir Notch – Integration of Engineering Designs, Telemetry, and Flow Fields

    Lead U.S. Army Corps of Engineers [USACE]
    Description This study analyzes 12 notch scenarios in the Fremont Weir in terms of entrainment of juvenile salmon. The goal is to quantify the relative entrainment rates (between 0 and 1) across the suite of scenarios and to identify possible strategies for enhancing entrainment outcomes. This study does not predict future entrainment as models generally do not predict future outcomes so much as highlight trends
    Science topics Chinook Salmon, Endangered species, Water conveyance / infrastructure
    Updated April 29, 2022
  • Title

    Reevaluating ecosystem functioning and carbon storage potential of a coastal wetland through integration of lateral and vertical carbon flux estimates

    Lead University of Washington [UW]
    Description This study aims to produce an integrated, net ecosystem carbon budget for Suisun Marsh, a representative ecosystem in the delta. This project combines diverse measurements on land and in the adjacent marine environment to produce the first directly measured, complete carbon budget for a coastal wetland habitat. This work has generated a more complete picture of the potential of wetland preservation for greenhouse gas reduction, as well as the processes that shape wetland accretion and resilience to sea-level rise. The project will provide vital information for understanding the ecosystem services, food webs, and carbon storage potential of the region’s wetlands, as well as provide new methodology that could be used by researchers around the world.
    Science topics Atmosphere, Carbon, Carbon storage, Evaporation / evapotranspiration, Non-forested vegetation, Sea level rise, Sediments, Surface water / flow, Wetlands
    Updated November 17, 2022
  • Title

    Hydrodynamic Influences on the Food Webs of Restoring Tidal Wetlands

    Lead California Department of Fish and Wildlife [CDFW]
    Description Funding will be use to implement targeted studies that examine the effect of hydrogeomorphology and biogeochemistry on aquatic habitat and resident fish. Increased knowledge of how physical processess drive fish and trophic interactions is imperative to the success of potential restoration projects in the region. Objectives are to evaluate and map the physical and hydrodynamic characteristics of the study sloughs;evaluate the effects of elevation and sea level rise;create a network of water quality stations to measure differences in slough functions;evaluate the influence of flow and tide on food production in sloughs and tidal wetlands;charaterize differences and evaluate how slough restoration effects food productions;evaluate fish community composition;evaluate fish response to habitat differences;evaluate fish use of wetlands as nursery habitats;develop recommendations for improving design of tidal wetland restoration projects to increase food availability for juvenile native fishes;evaluate the influence of flow and tide on trophic dynamics in sloughs and tidal wetlands;and characterize differences and evaluate how slough condition affects food production.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Application of cutting-edge tools to retrospectively evaluate habitat suitability and flow effects for Longfin Smelt

    Lead University of California - Davis [UC Davis]
    Description The Longfin Smelt (Spirinchus thaleichthys) is a native forage fish, characteristic of the natural biological community of the San Francisco Estuary (SFE). This study will examine variation and interactions among hatch dates, instantaneous and total growth rates, habitat use, and timing of transitions among habitats with different salinities, and variation among years with very different climate and freshwater outflow conditions. This information is crucial for managing freshwater flows and can be used to evaluate the effects of tidal wetland restoration in the San Francisco Estuary.
    Science topics None specified
    Updated November 19, 2022
  • Title

    Impact of Spatial and Temporal Dynamics of Water Flows on Migratory Behavior of Chinook Salmon Smolts in the South Delta

    Lead University of California - Davis [UC Davis]
    Description Funding for this study project will be use track the swimming movements of salmon smolts during migration using acoustic transmitters and detection arrays near the confluence of Old River and the San Joaquin River. Analyses will be carried out to determine swimming velocity relative to current velocity. Modeling will estimate fish distribution; fish transit times; entrainment of fish into channels of the south Delta; and alternative water export management scenarios that may result in reduced entrainment.
    Science topics None specified
    Updated November 19, 2022
  • Title

    How Abiotic Processes, Biotic Processes, and Their Interactions Sustain Habiata Charactersitics and Functions in River Channels and Their Floodplains: An Investigation of How a Reach of the Merced River Responds to Restoration

    Lead University of California - Santa Barbara [UCSB]
    Description The purpose of this project is to determine how river restoration affects the abundance and distribution of salmonid and non-salmonid fishes at critical life stages. The proposal involves field survey of hydraulics, sedimentation processes, channel changes, habitat conditions, invertebrate and fish communities and their interactions.
    Science topics None specified
    Updated April 29, 2022
  • Title

    A Calibration-Free Approach to Modeling Delta Flows and Transport

    Lead University of California - Berkeley [UC Berkeley]
    Description The purpose of this project is to develop and evaluate an integrated system for the prediction of Delta flows and transport in real-time that doesn't rely upon historical data sets for calibration and validation. The system consists of observational and computational components, along with real-time communication and coordination.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Pilot Mark-Recapture Study to Estimate Delta Smelt Pre-Screen Loss and Salvage Efficiency

    Lead U.S. Fish and Wildlife Service [USFWS]
    Description The purpose of this project is to perform a study to determine whether it is feasible to quantify entrainment losses of juvenile and adult delta smelt due to water exports. This information is critical to better understanding the movement of Delta smelt in the system.
    Science topics Delta Smelt
    Updated April 29, 2022
  • Title

    A Non-Point Source of Contaminants to the Estuarine Food Web: Mobilized Particles from the Intertidal Zone

    Lead California State University [CSU]
    Description The purpose of this research project is to quantify the process of contaminant concentration and resuspension of shallow and intertidal cohesive sediments at sites along the salinity gradient from Prospect Island to San Pablo Bay. This research is important because it helps to understand the pathways by which contaminants are assimilated, which is essential to appropriately manage habitat areas.
    Science topics None specified
    Updated April 29, 2022
  • Title

    A Statistical Model of Central Valley Chinook Incorporating Uncertainty

    Lead R2 Resource Consultants Inc.
    Description The purpose of this project is to develop a statistical modeling approach to the two Central Valley Chinook Salmon species that incorporates mortality in all phases of salmon life history, and includes the effects of uncertainty in assessing population status, guiding future research, and making management decisions.
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    Quantifying Factors Affecting Migration Routing and Survival of Juvenile Late-Fall Chinook Salmon in the Sacramento-San Joaquin River Delta

    Lead U.S. Geological Survey [USGS]
    Description Juvenile Chinook salmon emigrating from natal tributaries of the Sacramento River must negotiate the Sacramento-San Joaquin River Delta where they disperse among the Delta's complex channel network. Natural processes and water management actions affect the fraction of the population using different migration routes through the Delta and survival within those routes, but quantifying these relationships has proven difficult. Since 2006, acoustic telemetry techniques have been used to quantify both movement among migration routes and survival within routes, providing the first insights into how route-specific survival contributes to population-level survival in the Delta. In this project, we propose to use existing acoustic telemetry data from multiple sources to 1) Quantify factors affecting migration routing of juvenile salmon emigrating from the Sacramento River, 2) Quantify factors affecting survival of juvenile salmon within specific migration routes, and 3) Simulate population-level survival through the Delta under a limited number of historical and operational scenarios. Collating telemetry data from multiple sources over numerous years offers a unique opportunity to identify important relationships that might otherwise be difficult to detect for any particular study in a given year. Quantifying such relationships is critical to informing resource management that seeks to balance use of water resources with recovery of endangered salmon populations.
    Science topics Chinook Salmon
    Updated April 29, 2022
  • Title

    An Open-Source, Three-Dimensional Unstructured-Grid Model of the Sacramento/San Joaquin Delta: Model Construction and Application to Delta Hydrodynamics and Temperature Variability

    Lead Stanford University
    Description Motivated by the need to predict transport in the Delta, this project will apply the open-source, unstructured-grid computer model, SUNTANS (Stanford Unstructured Nonhydrostatic Terrain following Adaptive Navier Stokes simulator) to the Sacramento/San Joaquin Delta. SUNTANS solves the governing equations of fluid flow on a grid that permits fine detail in areas of particular interest in the Delta, while allowing us to include the entirety of the Bay/Delta system so as to properly model oceanic and estuarine influences on the Delta We have two aims:(1) to carry out the model development needed to apply SUNTANS to the Delta;(2) to apply the model to look at aspects of the physical variability of the Delta that are critical to ecosystem function and to understanding how physical processes in the Delta affect ecosystem function, most notably entrainment of fish and other organisms by the export facilities. In particular, we propose to look at flow behavior at channel junctions, a key aspect of Delta hydrodynamics that influences dispersion in the Delta and thus the transport of biota, nutrients and contaminants. We also will examine the dynamics of spatial and temperature variability in the Delta in response to tides, atmospheric forcing, river flows, and diversions, variability that must be properly calculated to forecast how climate change and altered project operations may affect key species like Delta Smelt. We will carry out new fieldwork to support our modeling.
    Science topics Water temperature
    Updated April 29, 2022
  • Title

    Integrating Ecosystems, Flood Control, Agriculture, and Water Supply Benefits: An Application to the Yolo Bypass

    Lead University of California - Davis [UC Davis]
    Description The Yolo Bypass presents an opportunity to develop mechanisms governing the management of flows across floodplains that balance ecosystem services with economic and recreational functions, and to study the untapped potential of such floodplains to play a role in conjunctive surface and groundwater management. Analysis to the necessary high degree of spatial resolution for such management decisions is generally lacking for the Yolo Bypass. This proposal seeks funding for an interdisciplinary study to better understand the economic, hydrologic, and ecological functioning of land and water across the bypass, and to develop tools that use this knowledge in identifying promising strategies for the timing and configuration of spring inundation. Agronomic, economic, and hydraulic models will be used with formal interviews to study the relationship between flooding and six Yolo Bypass functions: (1) Agricultural Economics, (2) Waterfowl management, (3) Native Fish habitat, (4) Flood Control, (5) Groundwater storage, and (6) Recreation. Data from these first efforts will be incorporated into an optimization model that identifies promising inundation alternatives for ecosystem services which minimize costs to landowners and waterfowl managers, and maximize potential conjunctive use benefits. This synthesis answers the Delta Science Program's request for coupled hydrologic and ecosystem models, and for water and ecosystem management decision support system development.
    Science topics None specified
    Updated April 29, 2022
  • Title

    CASCaDE II: Computational Asessments of Scenarios of Change for the Delta Ecosystem

    Lead U.S. Geological Survey [USGS]
    Description This proposal builds upon an existing model-based effort to develop a holistic view of the Bay-Delta-River-Watershed system. CASCaDE I developed a set of linked models to assess Delta ecosystem response to climate change. In CASCaDE II, we propose to refine and extend those modeling capabilities to assess Delta ecosystem response to changes in climate and physical configuration. With a new state-of-the-art hydrodynamic and sediment model at its core, CASCaDE II will link models of climate, hydrology, hydrodynamics, sediment, geomorphology, phytoplankton, bivalves, contaminants, marsh accretion, and fish. Our goals are to apply these linked models to 1) better understand Delta ecosystem function, 2) assess possible futures of the Delta under scenarios of climate and structural change, and 3) provide science-based information to support the DSC in its co-equal goals of water supply and ecosystem protection. The tools developed will provide an objective basis for anticipating and diagnosing Delta ecosystem responses to planned and unplanned changes. Experiments using the linked models are designed to address questions such as: How will climate change, together with new conveyance structures or increased flooded island habitat, alter water flow and drinking water quality? With projected changes in residence time, turbidity, temperature, and salinity, how will primary productivity, invasive bivalves, marsh processes, contaminant dynamics, and fish populations respond?
    Science topics None specified
    Updated April 29, 2022
  • Title

    Estuarine fish community responses to climate, flow, and habitat

    Lead University of California - Berkeley [UC Berkeley]
    Description The goal of this research is to better understand how climate change will affect fishes with different life histories and habitat associations across the San Francisco Estuary. Existing datasets will be incorporated in synthetic analyses and cutting-edge statistical models to identify fish community responses to climate, flows, and habitats along the estuarine salinity gradient. This synthesis-science project will use rich long-term datasets that have been collected by Bay-Delta researchers for decades that will then be analyzed in a reproducible and open science framework. It will also support efforts by the Interagency Ecological Program’s Climate Change Project Work Team.
    Science topics Estuaries
    Updated April 29, 2022
  • Title

    Survivial and Migratory Pattern of Central Valley Juvenile Salmonids

    Lead University of California - Davis [UC Davis]
    Description The purpose of this project is to determine the survival and movement patterns of late-fall Chinook salmon smolts and steelhead smolts as they migrate downstream. This information is important to better understand how salmon move through the system.
    Science topics None specified
    Updated April 29, 2022
  • Title

    North Delta Flow Action: Role of Improved Yolo Bypass Flows on Delta Food Web Dynamics

    Lead California Department of Water Resource [DWR]
    Description Description In a collaborative effort between CA Department of Water Resources, US Bureau of Reclamation, CA Department of Fish and Wildlife, United States Geological Survey, San Francisco State University, and UC Davis, this study will investigate the role of augmented summer and fall flows in the Yolo Bypass and North Delta areas on lower trophic food web dynamics and the benefits to listed fish species. Using both continuous and discrete sampling approaches, this study will relate hydrologic patterns to chlorophyll-a, nutrients and primary productivity, plankton densities and composition (phytoplankton and zooplankton), contaminant concentrations, as well as water quality parameters such as electrical conductivity, turbidity, temperature, and dissolved oxygen. In addition, caged hatchery Delta Smelt will be monitored to determine the effects of the managed flow action and increased food web productivity on fish survival, growth, and behavior. Need Due to the food-limited nature of the San Francisco Estuary, it is critical to understand mechanisms that result in successful food web productivity including phytoplankton blooms. Food limitation is one of the primary hypothesized causes of the Pelagic Organism Decline. In 2011 and 2012 there was evidence that a moderate Yolo Bypass flow pulse during fall agricultural drainage periods was followed by phytoplankton blooms in the lower Sacramento River. Managed flow actions in the following years showed an increase in food web productivity could be repeated;however, results varied across years and flow actions indicating more research is warranted to understand correlations between flow and abiotic conditions, and the biological response of the food web. The increases of summer/fall flows in North Delta, has been considered a management strategy as part of complying with USFWS Delta Smelt Biological Opinion Action 4. The augmentation of flows through the Yolo Bypass/North Delta is also included as one of several Delta Smelt Resiliency Strategies by Natural Resources Agency. Objectives • Determine if managed flow actions through the Yolo Bypass stimulate increased primary productivity locally and downstream, and if it is repeatable. • Characterize how nutrients, chlorophyll and plankton (composition and density) in the Toe Drain, Cache Slough Complex, and lower Sacramento River change in response to flow pulses. • Determine if nutrient subsidies of the source water and downstream are limited by abiotic and biotic factors. • Characterize spatial differences and transport of pesticide contaminants in the Yolo Bypass in response to the flow actions. • Determine survival, growth and behavior of caged hatchery Delta Smelt before and after the flow action in the Yolo Bypass.
    Science topics Flows, Water management
    Updated April 29, 2022
  • Title

    Red Bluff Diversion Dam Rotary Screw Traps

    Lead U.S. Bureau of Reclamation [USBR]
    Description Annual juvenile production estimates for ESA species in Sacramento River, Clear Creek, and Battle Creek
    Science topics None specified
    Updated April 29, 2022
  • Title

    Directed Outflow Project [DOP] - Paired Habitat Sampling

    Lead U.S. Bureau of Reclamation [USBR]
    Description Special study supporting water quality, food web, and biological measures regarding seasonal outflow and Delta Smelt.
    Science topics Flows, Water management
    Updated April 29, 2022
  • Title

    Examining the relationship between Longfin Smelt and flow in the San Francisco Bay Delta

    Lead University of California - Berkeley [UC Berkeley]
    Description The overarching goal of this study is to investigate the time-varying effects of flow variation and food availability on longfin smelt population dynamics, via advanced modeling of a diverse set of environmental and ecological monitoring time series. Specifically, this project will:(1) Assess how key environmental drivers (flow, salinity, temperature) have changed over the past 5 decades (1967 to present) across the San Francisco Estuary (SFE); (2) Examine how longfin smelt population dynamics have changed over that time period, and whether/when breakpoints in abundance and trends exist (e.g., periods of 'decline' vs' stability'); (3) Quantify the effects of environmental on driving observed fluctuations in longfin smelt dynamics; (4) Determine whether/how environment-smelt relationships have changed in magnitude or sign over time; and if they changed, whether such changes have been spatially consistent across the SFE. These goals will inform ongoing conservation efforts of longfin smelt by determining the combinations of flow, habitat, and prey availability conditions that lead to stable population dynamics for the species.
    Science topics Fish, Flows, Longfin Smelt, Zooplankton
    Updated May 8, 2024
  • Title

    Assessing sea-level rise and flooding changes in the Sacramento/San Joaquin Delta using historical water-level records

    Lead California State University [CSU]
    Description The project aims to recover, digitize, and analyze more than 1300 station years of ‘lost-and-forgotten’ water level records collected from 1857 to 1982 in the Sacramento-San Joaquin Delta. These measurements, augmented by modern data, will improve our understanding of tidal, flood, and sea level trends in the system. By determining ‘hotspots’ of habitat and flood risk sensitivity, the results may be used to better focus future scientific and management priorities, to protect the environment, manage flood risk, and enhance community resilience to climate change
    Science topics Backwater, Climate change, Environmental drivers, Estuaries, Land elevation, Levees, Outflow, Sea level rise, Stage, Subsidence, Surface water / flow, Tides, Velocity, Vessels and shipping channels, Water, Wind
    Updated October 10, 2023
  • Title

    Continuous Flow and Water Quality Monitoring Network in the Sacramento-San Joaquin Delta

    Lead U.S. Geological Survey [USGS]
    Description This project envisions the continuation, expansion, and further integration of high frequency monitoring for flow, water quality (including chlorophyll and nutrients), sediment, as well as biological responses at key locations in the Delta and Suisun Bay. The physical properties monitored by the fixed-station network are the primary drivers of the habitat conditions and biological responses that management actions hope to achieve. Nutrient dynamics are explicitly measured at select stations to improve our understanding of how physical dynamics, water quality and landscape features shape the base of Delta food webs. These data will provide information about drivers linked to food quantity and quality as well as potential toxins production by harmful algae. Suspended-sediment monitoring provides an understanding of the inputs and internal exchanges between regions, locations of sources and sinks, and provides insight into the underlying cause of turbidity variability in the study area. Suspended-sediment measurements gage the availability of suspended sediment for existing marshes and for proposed large-scale marsh restoration efforts in the Delta. There are a total of 5 sub-tasks in this project: • Task 1: Hydrodynamics Team – Fixed Station Network Operation and Maintenance • Task 2: BioGeoChemistry Team -- Fixed Station Network Operation and Maintenance • Task 3: Delta Sediment Team – Fixed Station Network Operation and Maintenance • Task 4: Bay Sediment Team – Fixed Station Network Operation and Maintenance • Task 5: Project Management
    Science topics Chlorophyll A / B, Conductivity, Dissolved oxygen, Flows, Nutrients, pH, Phytoplankton, Sediments, Stage, Surface water / flow, Tides, Turbidity, Velocity, Water operations / exports, Water temperature
    Updated January 19, 2024