Skip to main content
U.S. flag

An official website of the United States government

California Water Science Center

The U.S. Geological Survey, California Water Science Center provides reliable, impartial, foundational data and scientific analysis to address water issues facing California today. We conduct hydrologic monitoring and investigative studies in partnership with tribal, federal, state, and local agencies to assist them in managing California's water resources.

News

link

Physics to Fish

link

USGS Supports Effort to Understand Impacts on Water Quality Caused by 2018 Camp Fire in Paradise, California

link

Streamgages Play Critical Role During Atmospheric Rivers

Publications

Evaluating the reliability of environmental concentration data to characterize exposure in environmental risk assessments

Environmental risk assessments often rely on measured concentrations in environmental matrices to characterize exposure of the population of interest—typically, humans, aquatic biota, or other wildlife. Yet, there is limited guidance available on how to report and evaluate exposure datasets for reliability and relevance, despite their importance to regulatory decision-making. This paper is the sec
Authors
Michelle Hladik, Arjen Markus, Dennis R. Helsel, Lisa H. Nowell, Stefano Polesello, Heinz Rudel, Drew Szabo, Iain Wilson

Methods of analysis—Determination of pesticides in filtered water and suspended sediment using liquid chromatography- and gas chromatography-tandem mass spectrometry

The widespread application of pesticides in agricultural and urban areas leads to their presence in surface waters. Presence of these biologically active chemicals in environmental waters potentially has adverse effects on nontarget organisms. To better understand the environmental fate of these contaminants, a robust method to capture chemicals with wide-ranging physicochemical properties has bee
Authors
Michael S. Gross, Corey J. Sanders, Matthew D. De Parsia, Michelle L. Hladik

Multigenerational, indirect exposure to pyrethroids demonstrates potential compensatory response and reduced toxicity at higher salinity in estuarine fish

Estuarine environments are critical to fish species and serve as nurseries for developing embryos and larvae. They also undergo daily fluctuations in salinity and act as filters for pollutants. Additionally, global climate change (GCC) is altering salinity regimes within estuarine systems through changes in precipitation and sea level rise. GCC is also likely to lead to an increased use of insecti
Authors
Sara Hutton, Samreen Siddiqui, Emily Pedersen, Christopher Markgraf, Amelie Segarra, Michelle Hladik, Richard E Connon, Susanne M. Brander

Science

Culturally Prescribed Fire

Culturally prescribed burning has been long practiced by the Yurok Tribe for a variety of reasons. This study explores using culturally prescribed fire as a land management tool for increasing the resiliency of streams and watersheds.
link

Culturally Prescribed Fire

Culturally prescribed burning has been long practiced by the Yurok Tribe for a variety of reasons. This study explores using culturally prescribed fire as a land management tool for increasing the resiliency of streams and watersheds.
Learn More

Water Availability of the Salton Sea Watershed

Throughout history, the Salton Sea has formed and dried up due to flooding from the Colorado River. It was most recently formed in 1905 when the Colorado River broke through an irrigation canal and flowed uncontrolled into the Salton Sea watershed. The Salton Sea is a terminal lake (it has no outlets). It is also in transboundary watershed, with area in both the state of California and Mexico’s...
link

Water Availability of the Salton Sea Watershed

Throughout history, the Salton Sea has formed and dried up due to flooding from the Colorado River. It was most recently formed in 1905 when the Colorado River broke through an irrigation canal and flowed uncontrolled into the Salton Sea watershed. The Salton Sea is a terminal lake (it has no outlets). It is also in transboundary watershed, with area in both the state of California and Mexico’s...
Learn More

Hazards Summary for Mammoth Mountain

Pyroclastic flow and carbon dioxide hazards at Mammoth Mountain.
link

Hazards Summary for Mammoth Mountain

Pyroclastic flow and carbon dioxide hazards at Mammoth Mountain.
Learn More