Publications
The following list of California Water Science Center publications includes both official USGS publications and journal articles authored by our scientists.
Filter Total Items: 1734
Correspondence of biological condition models of California streams at statewide and regional scales
We used boosted regression trees (BRT) to model stream biological condition as measured by benthic macroinvertebrate taxonomic completeness, the ratio of observed to expected (O/E) taxa. Models were developed with and without exclusion of rare taxa at a site. BRT models are robust, requiring few assumptions compared with traditional modeling techniques such as multiple linear regression. The BRT m
Authors
Jason T. May, Larry R. Brown, Andrew C. Rehn, Ian R. Waite, Peter R Ode, Raphael D Mazor, Kenneth C Schiff
Hindcast of water availability in regional aquifer systems using MODFLOW Farm Process
Coupled groundwater and surface-water components of the hydrologic cycle can be simulated by the Farm Process for MODFLOW (MF-FMP) in both irrigated and non-irrigated areas and aquifer-storage and recovery systems. MF-FMP is being applied to three productive agricultural regions of different scale in the State of California, USA, to assess the availability of water and the impacts of alternative m
Authors
Wolfgang Schmid, Randall T. Hanson, Claudia C. Faunt, Steven P. Phillips
Land subsidence in the San Joaquin Valley, California, USA, 2007-14
Rapid land subsidence was recently measured using multiple methods in two areas of the San Joaquin Valley (SJV): between Merced and Fresno (El Nido), and between Fresno and Bakersfield (Pixley). Recent land-use changes and diminished surface-water availability have led to increased groundwater pumping, groundwater-level declines, and land subsidence. Differential land subsidence has reduced the fl
Authors
Michelle Sneed, Justin T. Brandt
An updated conceptual model of Delta Smelt biology: Our evolving understanding of an estuarine fish
The main purpose of this report is to provide an up-to-date assessment and conceptual model of factors affecting Delta Smelt (Hypomesus transpacificus) throughout its primarily annual life cycle and to demonstrate how this conceptual model can be used for scientific and management purposes. The Delta Smelt is a small estuarine fish that only occurs in the San Francisco Estuary. Once abundant, it i
Authors
Randy Baxter, Larry R. Brown, Gonzalo Castillo, Louise Conrad, Steven D. Culberson, Matthew P. Dekar, Melissa Dekar, Frederick Feyrer, Thaddeus Hunt, Kristopher Jones, Joseph Kirsch, Anke Mueller-Solger, Matthew Nobriga, Steven B. Slater, Ted Sommer, Kelly Souza, Gregg Erickson, Stephanie Fong, Karen Gehrts, Lenny Grimaldo, Bruce Herbold
Status and understanding of groundwater quality in the Sierra Nevada Regional study unit, 2008: California GAMA Priority Basin Project
Groundwater quality in the Sierra Nevada Regional (SNR) study unit was investigated as part of the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment Program Priority Basin Project. The study was designed to provide statistically unbiased assessments of the quality of untreated groundwater within the primary aquifer system of the Sierra Nevada. The prima
Authors
Miranda S. Fram, Kenneth Belitz
Groundwater quality in the Sierra Nevada, California
Groundwater provides more than 40 percent of California’s drinking water. To protect this vital resource, the State of California created the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The Priority Basin Project (PBP) of the GAMA Program provides a comprehensive assessment of the State’s groundwater quality and increases public access to groundwater-quality information. The Sier
Authors
Miranda S. Fram, Kenneth Belitz
Groundwater-quality data in the Santa Cruz, San Gabriel, and Peninsular Ranges Hard Rock Aquifers study unit, 2011-2012: results from the California GAMA program
Groundwater quality in the 2,400-square-mile Santa Cruz, San Gabriel, and Peninsular Ranges Hard Rock Aquifers (Hard Rock) study unit was investigated by the U.S. Geological Survey (USGS) from March 2011 through March 2012, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project (PBP). The GAMA-PBP
Authors
Tracy A. Davis, Jennifer L. Shelton
The role of tidal marsh restoration in fish management in the San Francisco Estuary
Tidal marsh restoration is an important management issue in the San Francisco Estuary (estuary). Restoration of large areas of tidal marsh is ongoing or planned in the lower estuary (up to 6,000 ha, Callaway et al. 2011). Large areas are proposed for restoration in the upper estuary under the Endangered Species Act biological opinions (3,237 ha) and the Bay Delta Conservation Plan (26,305 ha). In
Authors
Bruce Herbold, Donald Baltz, Larry R. Brown, Robin Grossinger, Wim J. Kimmerer, Peggy W. Lehman, Charles A. Simenstad, Carl Wilcox, Matthew L. Nobriga
Pesticide concentrations in frog tissue and wetland habitats in alandscape dominated by agriculture
Habitat loss and exposure to pesticides are likely primary factors contributing to amphibian decline in agricultural landscapes. Conservation efforts have attempted to restore wetlands lost through landscape modifications to reduce contaminant loads in surface waters and providing quality habitat to wildlife. The benefits of this increased wetland area, perhaps especially for amphibians, may be ne
Authors
Kelly L. Smalling, Rebecca Reeves, Erin L. Muths, Mark W. Vandever, William A. Battaglin, Michelle Hladik, Clay L. Pierce
Analysis of projected water availability with current basin management plan, Pajaro Valley, California
The projection and analysis of the Pajaro Valley Hydrologic Model (PVHM) 34 years into the future using MODFLOW with the Farm Process (MF-FMP) facilitates assessment of potential future water availability. The projection is facilitated by the integrated hydrologic model, MF-FMP that fully couples the simulation of the use and movement of water from precipitation, streamflow, runoff, groundwater fl
Authors
Randall T. Hanson, Brian Lockwood, Wolfgang Schmid
Groundwater-flow and land-subsidence model of Antelope Valley, California
Antelope Valley, California, is a topographically closed basin in the western part of the Mojave Desert, about 50 miles northeast of Los Angeles. The Antelope Valley groundwater basin is about 940 square miles and is separated from the northern part of Antelope Valley by faults and low-lying hills. Prior to 1972, groundwater provided more than 90 percent of the total water supply in the valley; si
Authors
Adam J. Siade, Tracy Nishikawa, Diane L. Rewis, Peter Martin, Steven P. Phillips
Groundwater-quality data in the North San Francisco Bay Shallow Aquifer study unit, 2012: results from the California GAMA Program
Groundwater quality in the 1,850-square-mile North San Francisco Bay Shallow Aquifer (NSF-SA) study unit was investigated by the U.S. Geological Survey (USGS) from April to August 2012, as part of the California State Water Resources Control Board (SWRCB) Groundwater Ambient Monitoring and Assessment (GAMA) Program’s Priority Basin Project (PBP). The GAMA-PBP was developed in response to the Calif
Authors
George L. Bennett V, Miranda S. Fram