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Delta-Wide Mapping Surveys: Water quality, nutrients, and phytoplankton

The Sacramento-San Joaquin River Delta and San Francisco Bay

Much of the fresh water used for agriculture, municipal and industrial use in central and southern California passes through the Delta, where it is subjected to tidal forcing and other inputs that impact its quality.

Bay Delta
  • Delta-Wide Mapping Survey: 2018

    2018 mapping survey parameters

    San Francisco Bay-Delta Water Quality, Nutrient, and Phytoplankton Mapping, 2018

  • Delta-Wide Mapping Surveys: 2018-2024

    2018-2024 comparison

    San Francisco Bay-Delta Water Quality, Nutrient, and Phytoplankton Mapping, 2018 through 2024 Comparison