USGS provides essential science to help ensure the health and function of the San Francisco Bay/Sacramento-San Joaquin Delta system. The “Bay-Delta” supplies water to 25 million California residents, farms, and habitats for fish and wildlife. Currently, USGS scientists are working on more than 90 research studies in the Bay-Delta.
Water Quantity and Quality
USGS has a vast network of monitoring stations in the Bay-Delta that collects real-time water-quantity and water-quality data, including water level, temperature, direction and speed, salinity, and clarity. These data are used daily by State and Federal water managers to balance the needs of California’s communities, agriculture, and wildlife.
Aquatic Stressors
Habitat Quality
Environmental Contamination
USGS studies contaminants in the Bay-Delta to understand and predict the impacts that they may have on human and wildlife health. The Bay-Delta has many contaminants of concern, including naturally occurring trace metals—such as mercury and selenium—as well as pesticides, excess nutrients, and harmful toxins released by algal blooms.
Trace Metals
Pesticides
Nutrients
Animals and Habitat
USGS provides essential science on ecosystem function to inform species survival and recovery and habitat restoration in the Bay-Delta. Studies include monitoring the health and status of crucial species and understanding the impacts of habitat loss, contaminants, invasive species, sea-level rise, and changes in temperature and salinity.
Avian Studies
Fish Studies
Bottom-Dwelling (Benthic) Invertebrates
Protected Terrestrial Species
Habitat Restoration
Marsh Sustainability
Natural Hazards
USGS provides essential science on ecosystem function to inform species survival and recovery and habitat restoration in the Bay-Delta. Studies include monitoring the health and status of crucial species and understanding the impacts of habitat loss, contaminants, invasive species, sea-level rise, and changes in temperature and salinity.
Earthquake Monitoring
Fault Characterization
Land Subsidence
USGS scientists are studying the causes and impacts of land subsidence to help protect Bay-Delta communities from flooding and ensure the integrity of water-conveyance systems in California’s Central Valley. Subsidence weakens levees and threatens crucial aqueducts that supply water to more than 25 million California residents and vast farmlands.
Delta Island Subsidence
San Joaquin Valley Subsidence
Climate Impacts
USGS science is providing information crucial to understanding how climate-induced impacts to the Bay-Delta region may affect fish and wildlife habitat locally, as well as agriculture and water availability in much of California. Reduced statewide precipitation, sea-level rise, and prolonged drought are major climate-change threats to the State.
Predictive Tools
Sea-Level Rise
Drought
Atmospheric River Storms
USGS—in cooperation with Federal, State of California, and local agencies; academia; and the public—is working to provide science essential to addressing issues in the Bay-Delta. Research topics include water quantity and quality, environmental contamination, animals and habitats, natural hazards, land subsidence, and climate impacts.
For more than a century, USGS scientists have conducted research in California’s Bay-Delta region. Informing natural-resource management decisions on the region’s issues, this research has been published in thousands of documents, some highlighted below. A link to the larger collection of published USGS science for the region is also provided.
Estimating juvenile Chinook salmon (Oncorhynchus tshawytscha) abundance from beach seine data collected in the Sacramento–San Joaquin Delta and San Francisco Bay, California
Bivalve effects on the food web supporting delta smelt - A long-term study of bivalve recruitment, biomass, and grazing rate patterns with varying freshwater outflow
High-resolution remote sensing of water quality in the San Francisco Bay-Delta Estuary
California's BAY-DELTA: USGS Science Supports Decision Making
The following video presentations highlight the work of USGS scientists in California’s Bay-Delta region. For more than a century, USGS science has informed natural-resource management decisions in the region.
Below are partners associated with this project.
- Overview
USGS provides essential science to help ensure the health and function of the San Francisco Bay/Sacramento-San Joaquin Delta system. The “Bay-Delta” supplies water to 25 million California residents, farms, and habitats for fish and wildlife. Currently, USGS scientists are working on more than 90 research studies in the Bay-Delta.
Water Quantity and Quality
USGS has a vast network of monitoring stations in the Bay-Delta that collects real-time water-quantity and water-quality data, including water level, temperature, direction and speed, salinity, and clarity. These data are used daily by State and Federal water managers to balance the needs of California’s communities, agriculture, and wildlife.
Aquatic Stressors
Habitat Quality
Environmental Contamination
USGS studies contaminants in the Bay-Delta to understand and predict the impacts that they may have on human and wildlife health. The Bay-Delta has many contaminants of concern, including naturally occurring trace metals—such as mercury and selenium—as well as pesticides, excess nutrients, and harmful toxins released by algal blooms.
Trace Metals
Pesticides
Nutrients
Animals and Habitat
USGS provides essential science on ecosystem function to inform species survival and recovery and habitat restoration in the Bay-Delta. Studies include monitoring the health and status of crucial species and understanding the impacts of habitat loss, contaminants, invasive species, sea-level rise, and changes in temperature and salinity.
Avian Studies
Fish Studies
Bottom-Dwelling (Benthic) Invertebrates
Protected Terrestrial Species
Habitat Restoration
Marsh Sustainability
Natural Hazards
USGS provides essential science on ecosystem function to inform species survival and recovery and habitat restoration in the Bay-Delta. Studies include monitoring the health and status of crucial species and understanding the impacts of habitat loss, contaminants, invasive species, sea-level rise, and changes in temperature and salinity.
Earthquake Monitoring
Fault Characterization
Land Subsidence
USGS scientists are studying the causes and impacts of land subsidence to help protect Bay-Delta communities from flooding and ensure the integrity of water-conveyance systems in California’s Central Valley. Subsidence weakens levees and threatens crucial aqueducts that supply water to more than 25 million California residents and vast farmlands.
Delta Island Subsidence
San Joaquin Valley Subsidence
Climate Impacts
USGS science is providing information crucial to understanding how climate-induced impacts to the Bay-Delta region may affect fish and wildlife habitat locally, as well as agriculture and water availability in much of California. Reduced statewide precipitation, sea-level rise, and prolonged drought are major climate-change threats to the State.
Predictive Tools
Sea-Level Rise
Drought
Atmospheric River Storms
- Science
USGS—in cooperation with Federal, State of California, and local agencies; academia; and the public—is working to provide science essential to addressing issues in the Bay-Delta. Research topics include water quantity and quality, environmental contamination, animals and habitats, natural hazards, land subsidence, and climate impacts.
- Publications
For more than a century, USGS scientists have conducted research in California’s Bay-Delta region. Informing natural-resource management decisions on the region’s issues, this research has been published in thousands of documents, some highlighted below. A link to the larger collection of published USGS science for the region is also provided.
Estimating juvenile Chinook salmon (Oncorhynchus tshawytscha) abundance from beach seine data collected in the Sacramento–San Joaquin Delta and San Francisco Bay, California
Resource managers rely on abundance or density metrics derived from beach seine surveys to make vital decisions that affect fish population dynamics and assemblage structure. However, abundance and density metrics may be biased by imperfect capture and lack of geographic closure during sampling. Currently, there is considerable uncertainty about the capture efficiency of juvenile Chinook salmon (OAuthorsRussell W. Perry, Joseph E. Kirsch, A. Noble HendrixBivalve effects on the food web supporting delta smelt - A long-term study of bivalve recruitment, biomass, and grazing rate patterns with varying freshwater outflow
Executive Summary Phytoplankton is an important and limiting food source in the Sacramento-San Joaquin Delta (the Delta) and San Francisco Bay; the decline of phytoplankton biomass is one possible factor in the pelagic organism decline and specifically in the decline of the protected delta smelt. The bivalves Corbicula fluminea andPotamocorbula amurensis have been shown to control phytoplankton biAuthorsJeff S. Crauder, Janet K. Thompson, Francis Parchaso, Rosa I. Anduaga, Sarah A. Pearson, Karen Gehrts, Heather Fuller, Elizabeth WellsHigh-resolution remote sensing of water quality in the San Francisco Bay-Delta Estuary
The San Francisco Bay–Delta Estuary watershed is a major source of freshwater for California and a profoundly human-impacted environment. The water quality monitoring that is critical to the management of this important water resource and ecosystem relies primarily on a system of fixed water-quality monitoring stations, but the limited spatial coverage often hinders understanding. Here, we show hoAuthorsCédric G. Fichot, Bryan D. Downing, Brian A. Bergamaschi, Lisamarie Windham-Myers, Mark C. Marvin-DiPasquale, David R. Thompson, Michelle M. GierachCalifornia's BAY-DELTA: USGS Science Supports Decision Making
U.S. Geological Survey (USGS) scientists are in the forefront of the effort to understand what causes changes in the hydrology, the ecology and the water quality of the Sacramento-San Joaquin River Delta and the San Francisco Bay estuary. Their scientific findings play a crucial role in how agencies manage the Bay-Delta on a daily basis.AuthorsJames Nickles, Kimberly Taylor, Roger Fujii - News
The following video presentations highlight the work of USGS scientists in California’s Bay-Delta region. For more than a century, USGS science has informed natural-resource management decisions in the region.
- Partners
Below are partners associated with this project.