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Records

  • Title

    Directed Outflow Project

    Lead U.S. Bureau of Reclamation [USBR]
    Description The U.S. Bureau of Reclamation (USBR) and California Department of Water Resources (DWR), along with collaborators, are continuing efforts to evaluate the hypothesized benefits of outflow and outflow alteration for Delta Smelt. The collective aim of these efforts is to better inform management actions that will bolster and stabilize the Delta Smelt population. The planned five-year Directed Outflow Project (DOP) seeks to assist in evaluating the overarching hypothesis that habitat quality and quantity is improved in the summer/fall when X2 is below 81 km and the LSZ occurs in Suisun Bay and Marsh, and this improvement in habitat conditions will translate into a greater catch density, health, and growth for Delta Smelt using this area
    Science topics Delta Smelt, Fish, Flows, Water management
    Updated November 17, 2022
  • Title

    Delta Landscapes Primary Production Project

    Lead San Francisco Estuary Institute [SFEI]
    Description This project compares first-order estimates of primary production among five major groups of primary producers, historically and today, to better identify the potential food production of different habitat types, and inform restoration actions that could increase food availability for wildlife.
    Science topics Primary production, Phytoplankton, Emergent macrophytes, Epiphytic algae, SAV/FAV
    Updated April 29, 2022
  • Title

    Quantifying the contribution of tidal flow variations to survival of juvenile Chinook salmon

    Lead U.S. Geological Survey [USGS]
    Description The purpose of this project is to quantify how tides in the Delta influence survival of juvenile salmon. Juvenile salmon survival increases when there is more flow and the river is less tidally influenced. We hypothesize that the increase in survival is because of reduced travel times causing less exposure to predators. This project will test this hypothesis using multiple models including ones that can predict how management actions that modify tidal patterns affect juvenile salmon survival.
    Science topics Chinook Salmon, Salmon migration, Surface water / flow, Tides, Water management
    Updated January 29, 2024
  • Title

    Resolving Contradictions in Foodweb Support for Native Pelagic Fishes

    Lead San Francisco State University [SFSU]
    Description Much research in the Delta has focused on foodweb dynamics, stimulated by evidence that low productivity of plankton is linked to declines in several fish species including the endangered delta smelt. Pseudodiaptomus forbesi is the most abundant copepod (small crustaceans) in the Delta in summer. It is an important food source for many fishes and makes up about half of the food of delta smelt. This study focuses on the feeding, reproduction, and growth of copepods as essential foodweb support for fishes. This work investigates four diverse habitats including two open-water channels and two shallow habitats. The researchers will measure copepods´ feeding rates on microscopic plants and animals, and relate feeding to their rates of growth and reproduction. Computer models will be used to estimate their movement and death rates. These results will show the sources of nutrition used for growth and reproduction of these key organisms. Results will inform how food webs respond to large scale changes in the Delta ecosystem, for example, restoration and the Sacramento wastewater treatment plant upgrade.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Next Generation Multi-Hazard Levee Risk Assessment

    Lead University of California - Los Angeles [UCLA]
    Description In June 2004, a 350-foot levee section gave way west of Stockton, flooding crops and more than a dozen homes, and challenging state officials to protect the state's water supply. What is the risk of that happening again somewhere in the Delta? In light of agricultural fields sinking, the sea level rising, more frequent and severe floods occurring, and earthquakes looming, improvements are estimated to cost $3.8 - $4.3 billion over the next few decades. This study combines 3-D representations with information on the levee’s structure to analyze how different levees respond to floods, sea level rise, and earthquakes. State officials released the last Delta Risk Management Strategy a decade ago. Since then, scientists have collected significant amounts of data and have developed new procedures to compute the risk of failure. This work will produce new Delta-wide data sets important for characterizing the hazards coming from floods and earthquakes. It will also develop the best method to conduct levee hazard assessments. Applying this new method will ensure wise investments and effective threat mitigation Delta-wide.
    Science topics None specified
    Updated April 29, 2022
  • Title

    Analysis of Delta Salinity during Extended Drought – Pilot Project

    Lead California Department of Water Resource [DWR]
    Description Managing California water operations for multiple priorities under long term drought conditions is becoming an increasing challenge which is compounded by potential sea level rise. This project is a pilot exercise to demonstrate the utility of hydrodynamic and salinity transport models in to understand options for salinity management under extended drought combined with climate change and sea level rise. The project will also consider how to make model outputs available and relevant to other modeling and environmental management decision making efforts. The full range of potential sea level rise, restoration and operational actions is extensive, involving many potential combinations of individual actions. Therefore, it is difficult to fully explore potential actions with high resolution multi-dimensional models. The proposed approach is to use high resolution multi-dimensional flow and transport models to evaluate changes in transport in the Delta under sea level rise, restoration, and operational scenarios. The predicted changes to salinity for a given scenario will inform operations modeling in CALSIM through re-calibration of an ANN to approximately account for the changed salinity response of the estuary. Operations modeling incorporating the revised ANN will then estimate Delta inflows and overall water cost to meet Delta standards for the scenario. “Round-trip” modeling will be performed using the detailed Delta models to verify that the predicted hydrologic inputs allow appropriate compliance with water quality standards and will provide other metrics related to Delta transport.
    Science topics Conductivity, Drought, Landscape change, Restoration planning, Sea level rise, Water operations / exports
    Updated January 29, 2024