California Water Science Center

Surface Water

Streams, rivers, lakes and reservoirs - collectively referred to as surface water - are important natural resources for irrigation, public supply, wetlands and wildlife. Surface water is also measured as annual runoff, which is the amount of rain and snowmelt drainage left after the demands of nature, evaporation from land, and transpiration from vegetation have been supplied. It supplies most of our basic water needs.

Filter Total Items: 114
Date published: November 27, 2018
Status: Active

Pesticide Occurrence in California – Yolo Bypass Pesticide Analyses

The project is part of an overarching Interagency Ecological Program (IEP)/Department of Water Resources (DWR) study that is focused on understanding the processes by which the Yolo Bypass may provide a fall food web supply for the Cache Slough Complex and downstream regions of the Sacramento/San Joaquin Delta.  Several studies conducted since 2011 have shown that phytoplankton blooms can be...

Contacts: James Orlando
Date published: November 27, 2018
Status: Active

Effects of Climate on Snowmelt and Water Availability for Reservoirs in the Southern Sierra Nevada

Potential changes in air temperature and precipitation due to changes in climate may result in more variable or smaller snow packs and earlier snowmelt in the southern Sierra Nevada in upcoming years. These conditions are likely to result in increased difficulty in planning reservoir operations for hydroelectric power and water availability during springtime snowmelt in this region. Reservoir...

Date published: November 26, 2018
Status: Completed

Methylmercury cycling and export from agricultural and natural wetlands in the Yolo Bypass

The purpose of the work conducted by the USGS California Water Science Center is to help guide Yolo Wildlife Area management practices by identifying the relationships between management effects on dissolved organic matter properties and the resulting role of dissolved organic matter in mercury methylation and biotic uptake measured by the cooperating USGS scientists. The information gathered...

Contacts: Jacob A Fleck
Date published: November 26, 2018
Status: Completed

Development of Precipitation-Runoff Modeling System (PRMS) for the Yuba River Basin, Northeastern California, with application for streamflow predictability and flood forecasting

Reservoirs in the Yuba River Basin are operated by the US Army Corps of Engineers (USACE) as part of the Feather-Yuba Forecast Coordinated Operations Program, and play an important role in flood management, water quality, and the health of fisheries as far downstream as the Sacramento-San Joaquin Delta. The basin has been developed for hydropower and irrigation diversions, so that measured...

Contacts: Kathryn Koczot
Date published: November 20, 2018
Status: Completed

Spatially Explicit Mapping of Hydrologic Residence Time Paired with Water Quality Measurements to Determine the Effects of the Emergency Drought Barrier

The purpose of this study is to assess the distribution of water residence times across the central Delta using rapid water isotope measurements (δ2H, δ18O) made with a boat-based flow-through instrument.

Contacts: Bryan Downing
Date published: November 20, 2018
Status: Active

Aquifer Storage and Recovery

Aquifer storage and recovery (ASR) is a water resources management technique for actively storing water underground during wet periods for recovery when needed, usually during dry periods. The timeframe can range from months to decades. Intentional aquifer storage, with the intent of using the water later, has been used for hundreds of years, but is being further developed and refined as...

Contacts: Claudia C Faunt
Date published: November 19, 2018
Status: Completed

Enterococcus Surface Protein as an Indicator of Human Fecal Pollution in the Lower Russian River Basin

Preliminary evaluation of water-quality data collected in the Lower Russian River Basin, Sonoma County, California during an on-going program by the U.S. Geological Survey (USGS), in cooperation with Sonoma County Water Agency (SCWA), indicated that there is considerable variability in bacterial concentrations from reach to reach and from year to year. Furthermore, tributaries that maintained...

Contacts: Robert Anders
Date published: November 16, 2018
Status: Active

Wildfires and Climate

Over the last several decades, both the incidence of large wildfires and the duration of the wildfire season across much of the United States have increased (Westerling and others, 2006, American Water Works Assn, 2008; Finco and others, 2012). Future wildfire projections based on forecasted climate scenarios indicate both an increase in the expected severity of wildfires, and an...

Date published: November 16, 2018
Status: Completed

Water-Quality Inventory Pesticides in the Golden Gate National Recreation Area

In 1998, all urban creeks in the San Francisco Bay Area were added to the Clean Water Act Section 303d list due to known or suspected diazinon impairment. Diazinon is an organophosphorus insecticide used on lawns, and fruit and vegetables. This pesticide has since been "phased out" and has not been available for purchase since late 2004. Diazinon use is declining and is being replaced by other...

Date published: November 15, 2018
Status: Active

Variability of Salinity and Temperature In San Francisco Bay

The USGS has been collecting specific conductance (salinity) and water temperature data in San Francisco Bay (SF Bay) since 1990. Data are typically collected at 5-10 fixed locations throughout the bay, every fifteen minutes, every minute of the day.

Date published: November 15, 2018
Status: Active

High-Speed Mapping of Nutrient Distributions and Water Quality Survey - Lower South San Francisco Bay

This project aims to characterize spatial heterogeneity for key water quality parameters, and pilot the use of underway-flowthrough mapping of biogeochemical properties as a cost-effective approach to monitoring. 

Date published: November 15, 2018
Status: Active

Delta Regional Monitoring Program: Current-use Pesticides

This study will utilize the unique analytical capabilities of the USGS Pesticide Fate Research Group (PFRG), Organic Chemistry Research Laboratory (OCRL) to assess the occurrence of a large suite of understudied, current-use pesticides and pesticide degradates in surface waters entering the Sacramento/San Joaquin Delta. 

Contacts: James Orlando