California Water Science Center


The California Water Science Center has adjusted activities in response to guidance concerning the global COVID-19 pandemic. We will carry on the work of the USGS, while also maintaining the health and safety of our employees and community.  Based on direction from the White House, the CDC, and state and local authorities, we are shifting to a virtual mode. 

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Water Research Projects

Water Research Projects

Over 100 research projects addressing California's key water issues including: long-term water supply and availability, water quality, droughts and floods, climate change, aquatic ecology, the Delta, management of watersheds and groundwater.

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Partnering with Us

Partnering with Us

The USGS partners with local, state, and other federal agencies to provide scientific information needed by water-resources managers across the Nation.

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California Water Data

Basic hydrologic data collection, processing, analysis, dissemination, and archiving are major parts of the California Water Science Center program.

National Water Information System Mapper

Current California Streamflow Conditions

California Runoff

USGS WaterWatch

USGS Flood Event Viewer

California Post-Fire Debris-Flow Maps

California Water-Quality Mapper

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Date published: September 17, 2021

Public notice for the upgrade and expansion of the water monitoring network in the Sacramento-San Joaquin Delta

The U.S. Geological Survey (USGS) provided the public an opportunity  to review and comment on an Environmental Assessment (EA) for the construction, upgrade, and maintenance of new and existing monitoring stations in the Sacramento-San Joaquin Delta (Delta). Public...

Date published: September 16, 2021

USGS Scientists Compare Analytical Methods for the Analysis of Imidacloprid in Biological Matrices

In a recent research project, California Water Science Center scientists compared analytical techniques for the analysis of imidacloprid in biological matrices.

Date published: September 1, 2021

Increased Pumping in California’s Central Valley During Drought Worsens Groundwater Quality

SACRAMENTO, Calif. – Intensive pumping of aquifers during drought can speed up deterioration of groundwater quality, according to a new study by the U.S. Geological Survey. The results highlight clean drinking water supply vulnerabilities in California and other western states currently experiencing record drought conditions.


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Year Published: 2022

Evaluation of ELISA for the analysis of imidacloprid in biological matrices: Cross-reactivities, matrix interferences, and comparison to LC-MS/MS

Imidacloprid is among the most used pesticides worldwide and there are toxicity concerns for nontarget organisms. Accurate and sensitive methods are necessary to quantitate imidacloprid concentrations in biological matrices to better understand their fate and effects. Here we evaluated an enzyme-linked immunosorbent assay (ELISA) kit for...

Gross, Michael S.; Woodward, Emily; Hladik, Michelle

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Year Published: 2021

Development of a groundwater-simulation model in the Los Angeles Coastal Plain, Los Angeles County, California

Executive SummaryThe Los Angeles Coastal Plain (LACP) covers about 580 square miles and is the largest coastal plain of semiarid southern California. The LACP is heavily developed with mostly residential, commercial, and industrial land uses that rely heavily on groundwater for water supply. In 2010, the LACP was home to about 14 percent of...

Paulinski, Scott
Paulinski, S., ed., 2021, Development of a groundwater-simulation model in the Los Angeles Coastal Plain, Los Angeles County, California: U.S. Geological Survey Scientific Investigations Report 2021-5088, 489 p.,

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Year Published: 2021

Continuous water-quality and suspended-sediment transport monitoring in the San Francisco Bay, California, water years 2018–19

Water-Quality in San Francisco BayThe U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay (Bay) as part of a multi-agency effort to address estuary management, water supply, and ecological concerns. The San Francisco Bay area is home to millions of people, and the Bay teems with marine and...

Einhell, Darin C.; Davila Olivera, Selina; Palm, Danielle L.
Einhell, D.C., Davila Olivera, S., and Palm, D.L., 2021, Continuous water-quality and suspended-sediment transport monitoring in the San Francisco Bay, California, water years 2018–19: U.S. Geological Survey Fact Sheet 2021-3043, 4 p.,