Water Quality
Providing foundational data and scientific analysis to address water quality issues facing California
Providing foundational data and scientific analysis to address water quality issues facing California
California Flood Science
Helping emergency managers and others protect life and property from floods and other water-related hazards
Helping emergency managers and others protect life and property from floods and other water-related hazards
Surface Water
Understanding the science about California surface-water use for irrigation, public consumption, and ecosystems
Understanding the science about California surface-water use for irrigation, public consumption, and ecosystems
Science Programs and Partnerships
Supplying necessary scientific information to local, state, and federal agencies, and non-governmental organizations
Supplying necessary scientific information to local, state, and federal agencies, and non-governmental organizations
Aquatic Ecology
Gaining better understanding of the effects that human activity, hydrologic extremes, and climate change have on aquatic ecosystems
Gaining better understanding of the effects that human activity, hydrologic extremes, and climate change have on aquatic ecosystems
Groundwater
Using science to assess and quantify the availability and quality of California's groundwater resources
Using science to assess and quantify the availability and quality of California's groundwater resources
California Drought
Monitoring the effects of drought in California through data collection and research
Monitoring the effects of drought in California through data collection and research
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.
Large Storms & Floods in California History
Large Storms & Floods in California History
Storms unleash torrential rain and intense winds, posing significant challenges to infrastructure and triggering widespread flooding. Since it became a state in 1850, California has experienced numerous large storms and floods.
New Study on Mercury Contamination
New Study on Mercury Contamination
Legacy Mercury Contamination from Historical Gold Mining -- A visualization tool for spatial data on sediment, water, and biota in the Sierra Nevada, California
California Water & Drought Data
California Water & Drought Data
Basic hydrologic data collection, processing, analysis, dissemination, and archiving are major parts of the California Water Science Center program.
News
New Maps Identify Legacy Mercury Contamination in California’s Sierra Nevada
New Maps Identify Legacy Mercury Contamination in California’s Sierra Nevada
USGS Scientists Present Findings at Clear Lake Integrated Science Symposium 2024
USGS Scientists Present Findings at Clear Lake Integrated Science Symposium 2024
Publications
The anatomy of a drought in the upper San Francisco Estuary: Water quality and lower-trophic responses to multi-year droughts
Multi-year droughts are important and impactful features of California’s Mediterranean climate and can fundamentally affect the water quality and the ecosystem response of the San Francisco Estuary (Estuary) and the Sacramento-San Joaquin Delta (Delta). This study assesses data collected by long-term monitoring programs over the past 46 years (1975-2021) to evaluate how water quality in...
Three-dimensional hydrogeologic framework model of the Russian River watershed, California
The Russian River watershed is in northern Sonoma County and southern Mendocino County, California, in the northern part of the California Coast Ranges. The Russian River serves as a supply for agricultural irrigation and for municipal, domestic, and commercial uses. Through a cooperative agreement with the California State Water Resources Control Board and Sonoma County Water Agency...
Management of tidal wetland restoration and fish in the upper San Francisco Estuary: Where are we now and how do we move forward? A summary of the 2023 Wetland Science Symposium
Tidal wetland restoration to benefit at-risk fish species in the Sacramento-San Joaquin Delta and Suisun marsh has gained momentum over the past decade, much of it in response to mitigation requirements for the State Water Project and Central Valley Project. In fall 2023, the Department of Water Resources and the State Water Contractors convened a symposium, entitled Delta-Suisun Tidal...
Science
A National Predictive Model for PFAS Occurrence in Groundwater
In October of 2024, USGS Scientist’s published a study where they created a model to predict PFAS occurrence in groundwater at the depths of drinking water supplies. This model can help guide our partners to sample areas where PFAS in drinking water could be an issue for the public.
By
Ecosystems Mission Area, Water Resources Mission Area, Contaminant Biology, Environmental Health Program, Toxic Substances Hydrology, California Water Science Center, Eastern Ecological Science Center, Lower Mississippi-Gulf Water Science Center, New England Water Science Center, New Jersey Water Science Center, New Mexico Water Science Center, New York Water Science Center, Pennsylvania Water Science Center, South Atlantic Water Science Center (SAWSC), Western Ecological Research Center (WERC)
Coastal Wetland Vulnerability to Climate Change and Sea-Level Rise: Understanding Ecological Thresholds and Ecosystem Transformations
Eighteen USGS coastal scientists from all four coasts of the conterminous United States are working together to advance the understanding of climate change and sea-level rise impacts to coastal wetlands.
By
California Water Science Center, Chesapeake Bay Activities, Eastern Ecological Science Center, Florence Bascom Geoscience Center, Great Lakes Science Center, Pacific Coastal and Marine Science Center, St. Petersburg Coastal and Marine Science Center, Western Ecological Research Center (WERC), Western Geographic Science Center, Wetland and Aquatic Research Center , Woods Hole Coastal and Marine Science Center
In situ chlorophyll fluorometer validation and comparison study
The Sacramento-San Joaquin Delta (Delta) supplies drinking water to much of California. The Delta also provides irrigation water to the Central Valley and is an important habitat to many aquatic and terrestrial species. In the past decade, there has been an increase in harmful algal blooms (HABs) in the Delta. While some HABs are nontoxic, others contain cyanobacteria that can produce dangerous...