Measuring and Monitoring

The USGS closely monitors the occurence and effects of drought through data collection and research. USGS science supports water managers in preparing for possible future drought by providing information about long-term hydrologic, climatic, and environmental changes. These studies support successful planning and science-based decision-making by water managers who must address complex issues and...

Throughout the nation, the USGS operates a streamgage network in near real-time that helps emergency managers and others protect life and property due to floods and other water-related hazards. The USGS California Water Science Center maintains nearly 500 streamgages that provides key streamflow and water level data for flood forecasters, the public, and emergency managers at the federal, state...

As part of the Urban Waters Federal Partnership (UWFP), this project will enhance water-quality monitoring on a reach of the Los Angeles River slated for revitalization. The UWFP reconnects urban communities—particularly those that are overburdened or economically distressed—with their waterways by improving coordination among federal agencies.

The effect of selenium toxicity on wildlife has been known for more than 50 years. This issue drew particular attention in the 1980s when embryo deformity and mortality was observed in birds at a wildlife refuge in California. Harmful effects from selenium were determined to be connected to irrigation drainage water. As a result, an effort began to monitor levels of selenium in irrigation drainage...

John Izbicki, PhD, a Research Hydrologist with the U.S. Geological Survey (USGS) California Water Science Center (CAWSC), led a five-year scientific study to determine the range of natural and anthropogenic (human-caused) hexavalent chromium concentrations, also referred to as chromium-6 or Cr(VI), in Hinkley Valley. The study was cooperatively funded by the Lahontan Regional Water Quality Control...

Drought is making the Delta Saltier. Less freshwater coming from watershed runoff and reservoir releases means that more salty water flows into the Sacramento San Joaquin Delta (Delta) from the Pacific Ocean. Changes in Delta salinity have far-reaching impacts, affecting the water supply for agriculture, drinking, wildlife, and Delta ecosystems.

The USGS is collecting continuous and discrete monitoring data to document baseline conditions and physical responses in downstream river reaches before, during, and after dam removal. These monitoring data will be integral for post-removal assessments and collaborations with basin partners.

The Upper Feather River Watershed is one of California’s regions of highest precipitation. Its runoff provides the majority of water delivered by the State Water Project, an average 3.2 million-acre feet each year feeding into Lake Oroville.

The USGS seeks to increase understanding of the groundwater system in the vicinity of the Lower Colorado Water Supply Project well field and to estimate future groundwater levels and total dissolved solids concentrations in the wells and the long-term viability of the Lower Colorado Water Supply Project.

Keswick Reservoir, on the Sacramento River, receives both water and contaminants from the Spring Creek Debris Dam. The term contaminants refers here to different kinds of chemicals that are in some instances delivered to lakes and rivers. These chemicals can have a detrimental effect on drinking water supplies and the health of humans, fish, and other aquatic species.

Coastal vegetated habitats, such as tidal wetlands, play an active role in the global carbon cycle. This is done through the removal of CO2 by living vegetation through photosynthesis and by the decay of organic matter and its burial for hundreds to thousands of years.

A partnership between the USGS, Pepperwood Preserve, and Black Swift LLC aims to map soil and fuel moisture over wildfire-prone landscapes.