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Bay-Delta

The Sacramento-San Joaquin River Delta and San Francisco Bay make up the "Bay-Delta.” The USGS monitors flow, water quality, and other dynamics in the Bay-Delta system. Data are gathered and reported in a variety of ways including sediment sampling, mapping surveys, and data collected every 15 minutes at stationary monitoring sites.

Water Quality Mapping Comparisons 2018-2024

Map showing depth of a very intricate bay and delta system color-coded to enhance central bay channels and tidal channels.

Water quality mapping results and comparisons between 2018-2024

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USGS Science at Work in the San Francisco Bay Estuary

Side-looking acoustic Doppler velocity meter and water quality sonde

In an article written for the Interagency Ecological Program for the San Francisco Estuary, Dr. Paul Work and Dr. Maureen Downing-Kunz, of the California Water Science Center, provide examples of the work being done to measure water flow and quality.

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Topics Related to the Bay-Delta

See some of the other ways USGS science is at work in the San Francisco Bay and Sacramento-San Joaquin Delta.

Filter Total Items: 49
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Longfin Smelt

Exploring Drivers of Pelagic Fish Population Decline in Bay-Delta

USGS scientists develop spatially explicit ecosystem model to explore changes pelagic fish species population and distribution in the Sacramento-San Joaquin Delta and Suisun Bay.
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California Water Science Center
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Exploring Drivers of Pelagic Fish Population Decline in Bay-Delta

USGS scientists develop spatially explicit ecosystem model to explore changes pelagic fish species population and distribution in the Sacramento-San Joaquin Delta and Suisun Bay.
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