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: February 17, 2021

Scientists Study Longfin Smelt Distribution in the Coastal Pacific Ocean

USGS scientists have begun a project to estimate the marine distribution of longfin smelt (Spirinchus thaleichthys) along the North American Pacific coast.

Date published: February 16, 2021

Public Webinar on the USGS study results for  Groundwater Quality of Aquifers Overlying the Oxnard Oil Field, Ventura County, California

The USGS and State Water Board Oil and Gas Regional Groundwater Monitoring Program are hosting a webinar Friday, February 19 at 10am PT to discuss the scientific findings of the Groundwater Quality of Aquifers Overlying the Oxnard Oil Field, Ventura County, California study.

Date published: January 29, 2021

Scientists Assess Sediment Nutrient Storage and Release in California's Sacramento-San Joaquin Delta

California Water Science Center scientists have begun the first comprehensive assessment of sediment nutrient inventories and fluxes in the Sacramento-San Joaquin Delta (Delta). Their findings will serve as a baseline for assessing water quality improvements following upcoming upgrades to the Sacramento Regional Wastewater Treatment Plant and wetland restoration efforts.


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Year Published: 2021

Multi-taxa database data dictionary

The conservation of biological resources relies on the successful management of ecological and physiological research data. The Western Ecological Research Center of the U.S. Geological Survey is working with researchers, land managers, and decision makers from non-government organizations and city, county, state, and federal resource agencies to...

Watson, Elise; Rochester, Carlton J.; Brown, Chris W.; Holmes, Donn A.; Hathaway, Stacie A.; Fisher, Robert N.
Watson, E., Rochester, C.J., Brown, C.W., Holmes, D.A., Hathaway, S.A., and Fisher, R.N., 2021, Multi-taxa database data dictionary: U.S. Geological Survey Techniques and Methods 16–B1, 149 p.,

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Year Published: 2021

Environmental and anthropogenic drivers of contaminants in agricultural watersheds with implications for land management

If not managed properly, modern agricultural practices can alter surface and groundwater quality and drinking water resources resulting in potential negative effects on aquatic and terrestrial ecosystems. Exposure to agriculturally derived contaminant mixtures has the potential to alter habitat quality and negatively affect fish and other aquatic...

Smalling, Kelly; Devereux, Olivia H.; Gordon, Stephanie; Phillips, Patrick J.; Blazer, Vicki S.; Hladik, Michelle; Kolpin, Dana W.; Meyer, Michael T.; Sperry, Adam; Wagner, Tyler

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Year Published: 2021

Multi-region assessment of chemical mixture exposures and predicted cumulative effects in USA wadeable urban/agriculture-gradient streams

Chemical-contaminant mixtures are widely reported in large stream reaches in urban/agriculture-developed watersheds, but mixture compositions and aggregate biological effects are less well understood in corresponding smaller headwaters, which comprise most of stream length, riparian connectivity, and spatial biodiversity. During 2014–2017,...

Bradley, Paul; Journey, Celeste A.; Romanok, Kristin; Breitmeyer, Sara; Button, Daniel T.; Carlisle, Daren; Huffman, Bradley; Mahler, Barbara; Nowell, Lisa H.; Qi, Sharon L.; Smalling, Kelly; Waite, Ian R.; Van Metre, Peter C.