Unified Interior Regions

California

The Southwest Region includes California, Nevada, and Arizona. The Regional Office, headquartered in Sacramento, provides Center oversight and support, facilitates internal and external collaborations, and works to further USGS strategic science directions.

States L2 Landing Page Tabs

Filter Total Items: 393
Date published: October 30, 2017
Status: Active

Ecology and Population Dynamics of Ridgway's Rails along the West Coast of the U.S.

The Ridgway’s rail is a federal and state listed endangered species that occurs in wetlands along the Pacific Coast and from the Lower Colorado River drainage to southern Baja California. Three subspecies of Ridgway’s rail are found within the United States: the California Ridgway’s Rail, Yuma Ridgway’s rail, and Light-footed Ridgway’s rail.  All three subspecies have declined since 1900 as a...

Contacts: Michael Casazza
Date published: October 30, 2017
Status: Active

Wildland Fire Science in Forests and Deserts

Fuel conditions and fire regimes in western forests and deserts have been altered due to past land management, biological invasions, and recent extreme weather events and climate shifts. These changes have created extreme fire risk to local and regional communities, threatening their economic health related to wildland recreation, forest production, livestock operations, and other uses of...

Contacts: Matthew Brooks
Date published: October 30, 2017
Status: Active

Coastal Ecosystem Response to Sea-level Rise

USGS WERC’s Dr. Karen Thorne, her team of reseachers, and her partners are currently taking a local site network approach to describe current and future conditions and projected responses of coastal ecosystems to sea-level rise and other stressors. The Coastal Ecosystem Response to Climate Change (CERCC) program’s goal is to understand how ecosystems vary in their ability to keep up with sea-...

Date published: October 30, 2017
Status: Active

Aridlands Disturbances and Restoration Ecology

Desert landscapes are rapidly changing due to increases in invasive plant species, frequency of wildfires, urban and energy development, recreational use, military training, and climate variation. Dr. Todd Esque, USGS researchers, and collaborators are working together to investigate these changes and provide managers with key information that can be used to manage natural resources more...

Contacts: Todd Esque
Date published: October 30, 2017
Status: Active

Breeding and Wintering Ecology of Waterfowl

Western U.S. wetlands provide critical habitat for wintering and breeding waterfowl in California. WERC's Dr. Josh Ackerman is working toward collecting data to understand factors influencing duck nest success, to improve and restore breeding habitat for resident duck populations in California, and understand composition of predator communities. To learn more about how USGS WERC is...

Contacts: Josh T Ackerman
Date published: September 20, 2017

Land Treatment Digital Library

The LTDL was created by the U.S. Geological Survey (USGS) to catalog information about land treatments on Federal lands in the western United States for all interested parties. The flexible framework of the library allows for the storage of a wide variety of data in different formats. The LTDL currently stores previously established land treatments or what often are called legacy data. The...

Date published: August 5, 2017
Status: Active

RestoreNet: Distributed Field Trial Network for Dryland Restoration

U.S. Geological Survey (USGS) researchers and land managers are co-producing a network of restoration field trial sites on DOI and surrounding lands in the southwestern U.S. The network systematically tests restoration treatments across a broad range of landscape, soil, and climate conditions. Each site in the network is used to test suitable seed mixes and treatments that promote plant...

Contacts: Seth Munson, Molly McCormick, Katie Laushman, Rebecca Mann, Mike Duniway, Ph.D., Brad Butterfield, Elise Gornish, Loralee Larios, Akasha Faist, Helen Rowe, Christopher Lortie, Caroline A. Havrilla
Date published: August 5, 2017
Status: Active

Hazards Societal Consequences and Risk Communication

The Hazards Societal Consequences and Risk Communication project is led by Anne Wein at the Western Geographic Science Center (WGSC).

The umbrella project is Science Application for Risk Reduction (SAFRR), which estimates consequences of natural hazard disaster scenarios as a strategy to engage decision-makers in increasing a community’s ability to cope with the effects of a disaster....

Date published: June 22, 2017
Status: Active

Land use and tsunami hazards in the Pacific Northwest

Tsunamis have the potential to cause considerable damage to communities along the U.S. Pacific Northwest coastline. As coastal communities expand over time, the potential societal impact of tsunami inundation changes.

To understand how community exposure to tsunami hazards may change in coming decades, we projected future development (i.e. urban, residential, and rural), households, and...

Date published: June 22, 2017
Status: Active

California land-change projections

This dataset consists of modeled projections of land use and land cover and population for the State of California for the period 1970-2101. For the 1970-2001 period, we used the USGS's LUCAS model to "backcast" LULC, beginning with the 2001 initial conditions and ending with 1970. For future projections, the model was initialized in 2001 and run forward on an annual time step to 2100. In...

Date published: June 22, 2017
Status: Active

Land use and carbon modeling in the Sierra Nevada Mountains

The goal of this study was to develop an integrated, regional-scale terrestrial carbon model, which can project changes in ecosystem carbon dynamics resulting from both changing biophysical conditions (e.g. CO2 fertilization, changes in climate) and land-change processes (e.g. urbanization, agricultural intensification, wildfire, harvest).

Our objective was to develop a modeling...

Date published: June 9, 2017
Status: Active

Role Nutrients Play in Fish Death Rates at Rodeo Lagoon

Scientists investigate excessive nutients levels in Rodeo Lagoon that are believed to be cause of dying fish

Filter Total Items: 519
Date published: January 1, 2018

CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 wave-hazard projections: average conditions in Channel Islands

Model-derived significant wave height (in meters) for the given storm condition and sea-level rise (SLR) scenario.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-level rise (SLR) scenarios. CoSMoS v3.0 for So

Date published: January 1, 2018

Central California CoSMoS v3.1 projections of coastal cliff retreat due to 21st century sea-level rise

This dataset contains spatial projections of coastal cliff retreat (and associated uncertainty) for future scenarios of sea-level rise (SLR) in Central California. Present-day cliff-edge positions used as the baseline for projections are also included. Projections were made using numerical models and field observations such as historical cliff retreat rate, nearshore slope, coastal cl

Date published: January 1, 2018

Water well data used for preliminary regional groundwater salinity mapping near selected oil fields in central and southern California

This digital dataset is comprised of three separate data files that contain total dissolved solids, well construction, and well identifying information for 3,546 water wells used to map salinity in and around 31 southern and central California oil fields. Salinity mapping was done for 27 fields located in the southern San Joaquin Valley of Kern County (North Belridge, South Belridge,

Date published: January 1, 2018

High-Resolution Aeromagnetic Survey of Mountain Pass, California

A detailed aeromagnetic survey of Mountain Pass, California was flown by CGG Canada Services Ltd. (CGG) during November and December, 2016. The high-resolution helicopter survey was flown at a flightline spacing of 100 and 200 m, a flightline azimuthal direction of 70 degrees, a nominal flightline elevation above ground of 70 m, and consists of about 1,814 line-kilometers. Tie l

Date published: January 1, 2018

Study Boundary and Grid Cells for the North and South American, Cosumnes, and Mokelumne River Watersheds Shallow Aquifer Study Unit

The U.S. Geological Survey collected groundwater samples from 67 domestic wells and 1 spring used for domestic supply in Placer, El Dorado, Amador, and Calaveras Counties, California in 2016-2017. The sites were sampled for the Mokelumne, Cosumnes, and American River Watersheds (MCAW) Shallow Aquifer Study Unit of the California State Water Resources Control Board Groundwater Ambi

Date published: January 1, 2018

Repeat high-resolution bathymetry datasets collected between 2014 and 2016 of a field of crescent-shaped rippled scour depressions in northern Monterey Bay, California

Between November 2014 and June 2016 the U.S. Geological Survey, Pacific Coastal and Marine Science Center (PCMSC) conducted eight repeat, high-resolution bathymetry and acoustic-backscatter surveys of a small patch of seafloor offshore Santa Cruz in northern Monterey Bay, California. PCMSC also collected oceanographic time-series data over the same two-year period. This metadata file de

Date published: January 1, 2018

Bathymetry data collected in 2007 from the San Miguel Passage in the Channel Islands, California

This portion of the data release presents bathymetry data from the San Miguel Passage, in the Channel Islands, California. Bathymetry data were collected in the San Miguel Passage, Channel Islands, California in August 2007 by the U.S. Geological Survey, Pacific Coastal and Marine Science Center (USGS, PCMSC). Collection was accomplished using a 234.5 kHz SEA (AP) Ltd. SWATHpl

Date published: January 1, 2018

CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 wave-hazard projections: 20-year storm in Channel Islands

Model-derived significant wave height (in meters) for the given storm condition and sea-level rise (SLR) scenario.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-level rise (SLR) scenarios. CoSMoS v3.0 for So

Date published: January 1, 2018

Recent historical and projected (years 2006–99) areas (km2) of managed, flooded habitats used by waterbirds overwintering in Central Valley, California basins for 17 climate, urbanization, and water management scenarios.

Matchett and Fleskes (2018) evaluated availability of wetland and agricultural habitats used by waterbirds overwintering in the Central Valley of California under 17 scenarios of projected climate, urbanization, and water supply management (for more information about scenarios see scenario description and Table 1 in Matchett and Fleskes [2018]). Central Valley waterbird habitats investigated...

Date published: January 1, 2018

CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 wave-hazard projections: 100-year storm in Channel Islands

Model-derived significant wave height (in meters) for the given storm condition and sea-level rise (SLR) scenario.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of kilometers) of storm-induced coastal flooding and erosion for both current and future sea-level rise (SLR) scenarios. CoSMoS v3.0 for So

Date published: January 1, 2018

Geophysical and geochemical data for salinity mapping in the Midway-Sunset oil field area

The U.S. Geological Survey (USGS) and California State University-Sacramento, in cooperation with the California State Water Resources Control Board and U.S. Bureau of Land Management, compiled and analyzed data for mapping groundwater salinity in selected oil and gas fields in California. The data for the Midway-Sunset (MWSS) oil field includes digitized borehole geophysical data,

Date published: January 1, 2018

Recent historical and projected (years 2006–99) areas (km2) of managed, flooded habitats used by waterbirds overwintering in Central Valley, California basins for 17 climate, urbanization, and water management scenarios.

Matchett and Fleskes (2018) evaluated availability of wetland and agricultural habitats used by waterbirds overwintering in the Central Valley of California under 17 scenarios of projected climate, urbanization, and water supply management (for more information about scenarios see scenario description and Table 1 in Matchett and Fleskes [2018]). Central Valley waterbird habitats investigated...

Filter Total Items: 355
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Year Published: 1998

Chapter C. The Loma Prieta, California, Earthquake of October 17, 1989 - Landslides

Central California, in the vicinity of San Francisco and Monterey Bays, has a history of fatal and damaging landslides, triggered by heavy rainfall, coastal and stream erosion, construction activity, and earthquakes. The great 1906 San Francisco earthquake (MS=8.2-8.3) generated more than 10,000 landslides throughout an area of 32,000 km2; these...

Keefer, David K.
Chapter C. The Loma Prieta, California, Earthquake of October 17, 1989 - Landslides; 1998; PP; 1551-C; The Loma Prieta, California, Earthquake of October 17, 1989: Strong Ground Motion and Ground Failure; Edited by Keefer, David K.

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Year Published: 1998

Chapter B. The Loma Prieta, California, Earthquake of October 17, 1989 - Highway Systems

This paper summarizes the impact of the Loma Prieta earthquake on highway systems. City streets, urban freeways, county roads, state routes, and the national highway system were all affected. There was damage to bridges, roads, tunnels, and other highway structures. The most serious damage occurred in the cities of San Francisco and Oakland, 60...

Yashinsky, Mark
Chapter B. The Loma Prieta, California, Earthquake of October 17, 1989 - Highway Systems; 1998; PP; 1552-B; The Loma Prieta, California, Earthquake of October 17, 1989: Performance of the Built Environment; Yashinsky, Mark

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Year Published: 1998

Chapter B. The Loma Prieta, California, Earthquake of October 17, 1989 - Liquefaction

The 1989 Loma Prieta earthquake both reconfirmed the vulnerability of areas in the San Francisco-Monterey Bay region to liquefaction and provided an opportunity to test methodologies for predicting liquefaction that have been developed since the mid-1970's. This vulnerability is documented in the chapter edited by O'Rourke and by the investigators...

Holzer, Thomas L.
Chapter B. The Loma Prieta, California, Earthquake of October 17, 1989 - Liquefaction; 1998; PP; 1551-B; The Loma Prieta, California, Earthquake of October 17, 1989: Strong Ground Motion and Ground Failure; Edited by Holzer, Thomas L.

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Year Published: 1998

The influence of the San Gregorio fault on the morphology of Monterey Canyon

A side-scan sonar survey was conducted of Monterey Canyon and the San Gregorio fault zone, off shore of Monterey Bay. The acoustic character and morphology of the sonar images, enhanced by SeaBeam bathymetry, show the path of the San Gregorio fault zone across the shelf, upper slope, and Monterey Canyon. High backscatter linear features a few...

McHugh, C.M.G.; Ryan, William B. F.; Eittreim, S.; Donald, Reed
The influence of the San Gregorio fault on the morphology of Monterey Canyon; 1998; Article; Journal; Marine Geology; McHugh, C. M. G.; B. f. , Ryan, W.; Eittreim, S.; Donald, Reed

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Year Published: 1998

The Loma Prieta, California, Earthquake of October 17, 1989: Performance of the built environment

Professional Paper 1552 focuses on the response of buildings, lifelines, highway systems, and earth structures to the earthquake. Losses to these systems totaled approximated $5.9 billion. The earthquake displaced many residents from their homes and severely disrupted transportation systems. Some significant findings were: * Approximately 16,...

Coordinated by Holzer, Thomas L.
The Loma Prieta, California, Earthquake of October 17, 1989: Performance of the Built Environment; 1998; PP; 1552; Coordinated by Holzer, Thomas L.

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Year Published: 1997

Drainage-return, surface-water withdrawal, and land-use data for the Sacramento-San Joaquin Delta, with emphasis on Twitchell Island, California

Partial data on drainage returns and surface-water withdrawals are presented for areas of the Sacramento-San Joaquin Delta, California, for March 1994 through February 1996. These areas cover most of the delta. Data are also presented for all drainage returns and some surface-water withdrawals for Twitchell Island, which is in the western part of...

Templin, William E.; Cherry, Daniel E.
Drainage-return, surface-water withdrawal, and land-use data for the Sacramento-San Joaquin Delta, with emphasis on Twitchell Island, California; 1997; OFR; 97-350; Templin, William E.; Cherry, Daniel E.

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Year Published: 1997

Chapter D. The Loma Prieta, California, Earthquake of October 17, 1989 - Aftershocks and postseismic effects

While the damaging effects of the earthquake represent a significant social setback and economic loss, the geophysical effects have produced a wealth of data that have provided important insights into the structure and mechanics of the San Andreas Fault system. Generally, the period after a large earthquake is vitally important to monitor. During...

Reasenberg, Paul A.
Chapter D. The Loma Prieta, California, Earthquake of October 17, 1989 - Aftershocks and Postseismic Effects; 1997; PP; 1550-D; The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence; Edited by Reasenberg, Paul A.

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Year Published: 1996

Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Main shock characteristics

The October 17, 1989, Loma Prieta, Calif., earthquake (0004:15.2 G.m.t. October 18; lat 37.036? N., long 121.883? W.; 19-km depth) had a local magnitude (ML) of about 6.7, a surface-wave magnitude (MS) of 7.1, a seismic moment of 2.2x1019 N-m to 3.5x1019 N-m, a source duration of 6 to 15 s, and an average stress drop of at least 50 bars. Slip...

Spudich, Paul
Chapter A. The Loma Prieta, California, Earthquake of October 17, 1989 - Main Shock Characteristics; 1996; PP; 1550-A; The Loma Prieta, California, Earthquake of October 17, 1989: Earthquake Occurrence; Edited by Spudich, Paul

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Year Published: 1996

Riparian vegetation and its water use during 1995 along the Mojave River, Southern California

The extent and areal density of riparian vegetation, including both phreatophytes and hydrophytes, were mapped along the 100-mile main stem of the Mojave River during 1995. Mapping was aided by vertical false-color infrared and low-level oblique photographs. However, positive identification of plant species and plant physiological stress required...

Lines, Gregory C.; Bilhorn, Thomas W.
Riparian vegetation and its water use during 1995 along the Mojave River, Southern California; 1996; WRI; 96-4241; Lines, Gregory C.; Bilhorn, Thomas W.

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Year Published: 1995

Water-resources data network evaluation for Monterey County, California; Phase 2, northern and coastal areas of Monterey County

This report presents an evaluation of water- resources data-collection networks in the northern and coastal areas of Monterey County, California. This evaluation was done by the U.S. Geological Survey in cooperation with the Monterey County Flood Control and Water Conservation District to evaluate precipitation, surface water, and ground water...

Templin, W.E.; Smith, P.E.; DeBortoli, M.L.; Schluter, R.C.
Water-resources data network evaluation for Monterey County, California; Phase 2, northern and coastal areas of Monterey County; 1995; WRI; 95-4210; Templin, W. E.; Smith, P. E.; DeBortoli, M. L.; Schluter, R. C.

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Year Published: 1995

Land use and water use in the Antelope Valley, California

Urban land use and water use in the Antelope Valley, California, have increased significantly since development of the valley began in the late 1800's.. Ground water has been a major source of water in this area because of limited local surface-water resources. Ground-water pumpage is reported to have increased from about 29,000 acre-feet in 1919...

Templin, William E.; Phillips, Steven P.; Cherry, Daniel E.; DeBortoli, Myrna L.; Haltom, T.C.; McPherson, Kelly R.; Mrozek, C.A.
Land use and water use in the Antelope Valley, California; 1995; WRI; 94-4208; Templin, W. E.; Phillips, S. P.; Cherry, D. E.; DeBortoli, M. L.; Haltom, T. C.; McPherson, K. R.; Mrozek, C. A.

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Year Published: 1995

Look before you build; geologic studies for safer land development in the San Francisco Bay area

This Circular provides a general description of the types of geologic hazards that exist throughout the United States. In nontechnical language this book describes how geologic information can be incorporated in the land-use development process and contains useful discussion of several examples from the San Francisco Bay area and elsewhere in the...

Blair-Tyler, Martha
Look before you build; geologic studies for safer land development in the San Francisco Bay area; 1995; CIR; 1130; Blair-Tyler, Martha

Filter Total Items: 1,005
two men in camo-patterned overalls standing next to a boat on the shore of a river with an instrument on the ground.
December 31, 2017

Technicians prepare to board a boat to measure water flow.

USGS technicians prepare to board a boat to go out to the center of the channel in the San Joaquin River below Friant Dam to get an accurate measurement of water flow during releases from the Dam for flood control.

Air photo of Paul's slide (left); photo of repair equipment/construction (right)
December 31, 2017

Air photo, Paul's slide (left); repair equipment/construction (right)

Paul’s Slide. Left: Air photo taken May 27, 2017, one of many that Beth Haddon will analyze with structure-from-motion software to measure changes in ground elevation. Right: Caltrans employees and contractors use an excavator and bulldozer to remove Paul’s Slide debris from California State Highway 1. Note recent construction of concrete and a line of grouted reinforcing

...
 model grid with four rows and four columns showing A, types of cascading hydrologic response units (HRUs) and B, land-surface a
December 31, 2017

Model Grids with Cascading Hydrologic Response Units

Hypothetical model grid showing A, types of cascading hydrologic response units and B, land-surface altitudes and cascading flow directions.

man in yellow slicker standing in rushing river up to his thighs, holding a stick-like instrument in the water
December 31, 2017

Measuring streamflow in fast moving floodwater.

USGS hydrographer measuring streamflow using a handheld Acoustic Doppler Velocimeter in fast moving floodwater Cajon Creek near Keenbrook, California. 

Cheryl Hapke is now sharing her knowledge of the Big Sur region with Warrick’s team
December 31, 2017

Cheryl Hapke shares her knowledge of the Big Sur region

Cheryl Hapke is now sharing her knowledge of the Big Sur region with Warrick’s team, and she is eager to leap back into studies of Big Sur coastal change.

Satellite showing the burn scars from the Thomas fire in California
December 25, 2017

Southern California Wildfires Update

In the Landsat 8 image acquired on December 9, smoke is carried west by strong winds, which also continued to spread fire through the dry terrain, mountain passes, and canyons. The diagonal lines are an airplane contrail and its shadow cast on the ground. Landsat 8’s December 25 image reveals the burn scar and shows

...
December 15, 2017

Image of the Week - Southern California Wildfires, December 2017

The Thomas fire has burned more than 230,000 acres and continues to blaze across souther California. These images show some of the burn scar left behind.

At the USGS EROS Center, we study land change, operate the Landsat satellites, and maintain the longest, continuously acquired collection of images of the Earth's land surface.

USGS EROS Center (

A woman shows a young child how she uses sediment sieves.
December 9, 2017

Sifting sand with sieves

Research geologist Amy East (left) shows a budding geologist how to sift sand to determine its size during our Open House in Santa Cruz, California.

Two young children sit on top of machines that are not moving, in a yard.
December 9, 2017

Posing for pictures

Posing for pictures on personal watercraft during the USGS Open House in Santa Cruz in December, 2017 was very popular.

A man wearing glasses talks into a microphone while gesturing with his hand.
December 9, 2017

Talking to the news

Open house organizer Rex Sanders explains the wide range of USGS research for a TV interview. Screen capture from KION video.

A young boy sits atop a personal watercraft on the lawn outside a USGS building.
December 9, 2017

Checking out the personal watercraft

A future personal watercraft captain checked out the controls on a beautiful December day in Santa Cruz.

Filter Total Items: 938
Lidar image showing the upper parts of the landslide that occurred in northwest Washington on March 22, 2014.
May 14, 2014

Want to know how elevation will benefit your state? The USGS National Geospatial Program is advancing the 3D Elevation Program, known as 3DEP, in response to the growing need for high-quality three-dimensional representations of the Nation’s natural and constructed features.

USGS science for a changing world logo
May 7, 2014

Results of a new hydrologic model show a decrease in groundwater levels in response to pumping, which in turn causes a reduction in groundwater discharge to streams, a reduction in groundwater evapotranspiration, and a reduction in groundwater storage in the Santa Rosa Plain watershed.

USGS science for a changing world logo
April 30, 2014

The coastal geology of Simeonof Island, the southeastern-most island in the Shumagin archipelago of the Aleutian Islands, suggests the region has not experienced a great megathrust earthquake in at least the past 3,400 years.

Catastrophic Earthquakes – In a Crowded World Public Lecture Flyer
April 22, 2014

Why have there been so many catastrophic earthquakes at the beginning of the 21stcentury? On April 24th, USGS Research Geologist Thomas Holzer will tell us the history and future of earthquake death tolls, and the urbanization of the planet. Find out what makes modern megacities vulnerable to natural hazards.

USGS science for a changing world logo
April 22, 2014

Inorganic trace elements – fluoride, arsenic, molybdenum and boron – were detected at high concentrations in 42 percent of groundwater used for public supply in the Borrego Valley, and southern desert areas of California, according to a recent study by the U.S. Geological Survey. The USGS evaluated the quality of untreated groundwater for this study – not treated tap water.

Image:  Desert Perchlorate Field Work
April 3, 2014

Newly published research is the first to characterize the distribution and interactions of natural perchlorate in a terrestrial ecosystem. The study results are important in assessing risks associated with ecological and human health and with potential movement of natural perchlorate contamination into groundwater.

Lecture flyer thumbnail
March 24, 2014

How much will California's climate warm in future decades and what are the greatest vulnerabilities to climate change? On March 27th, USGS Climate Researcher Dan Cayan will explain about how scientists are investigating the way climate change might impact resources that are crucial to the state, including the Sierra Nevada snowpack, California coastal sea levels and the San Francisco Bay and Delta

USGS science for a changing world logo
March 20, 2014

Why does the 1964 Great Alaska Earthquake Matter 50 Years Later? Scientific experts will talk about a half-century of scientific and monitoring advances triggered by the 1964 events.

USGS science for a changing world logo
March 17, 2014

How does drought affect California's water supply? Does it impact the surface water only, or what about groundwater? How does it impact water quality? What about streamflow? How is the water shortage affecting ecosystems? How is the drought related to climate change?

Screenshot Location of Mammoth Mountain
February 18, 2014

The earthquake swarm under Mammoth Mountain which started on February 3, 2014 has declined over the past few days. The daily numbers of earthquakes, however, are not yet at background levels. Most earthquakes were (are) M1.5 and less.

Screenshot Location of Mammoth Mountain
February 6, 2014

An earthquake swarm under Mammoth Mountain (Mono County, CA), which started slowly on February 3, 2014 intensified in the early hours of February 5 with many small-magnitude earthquakes occurring in rapid succession, a phenomenon known as "spasmodic bursts."