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
Oceanography Beyond the Golden Gate
Information about the USGS Pacific Coastal and Marine Science Center's oceanographic studies offshore of San Francisco Bay, from 1989-2003.
SAGEMAP
A GIS Database for Sage-grouse and Shrubsteppe Management in the Intermountain West
Water-Quality Sampling at Five Hydrologic Benchmark Stations in the Western United States
The Hydrologic Benchmark Network (HBN) was established in 1963 to provide Swiftwater Creek, MT long-term measurements of streamflow and water quality in areas of the United States that are minimally affected by human activities. Historically, the HBN has used a fixed-interval sampling strategy, however other more robust sampling strategies are now available. Trend networks, for example, can...
Mapping Shipping Hazards in San Francisco Bay
Information about the 1997-1998 study by USGS Pacific Coastal and Marine Science Center, to map the floor of San Francisco Bay in order to reveal the bay's shipping hazards.
Reprocessed boomer 3D seismic-reflection data of field activity P-04-11-CC, in San Luis Obispo Bay, offshore of Pismo Beach, central California, 2011-12-06 to 2012-10-05
This dataset includes reprocessed boomer 3D seismic data collected by the Fugro Consultants Inc. in 2012, in San Luis Obispo Bay, offshore of Pismo Beach, central California.
CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 flood-hazard depth and duration projections: 100-year storm in Los Angeles County
Projected Hazard: Maximum depth of flooding surface (in cm) in the region landward of the present day shoreline that is inundated for the storm condition and sea-level rise (SLR) scenario indicated. Note: Duration datasets may have occasional gaps in open-coast sections.
Model Summary: The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) o
Water pressure/depth, velocity, and turbidity time-series data from SPA14 Bay shallows stations in San Pablo Bay and China Camp Marsh, California
Files contain hydrodynamic and sediment transport data for the location and deployment indicated. Time-series data of water depth, velocity, turbidity, and temperature were collected in San Pablo Bay and China Camp Marsh as part of the San Francisco Bay Marsh Sediment Experiments. Several instruments were deployed in tidal creek, marsh, mudflat, and Bay locations, gathering data on
Bathymetry hillshade--Offshore of Point Conception Map Area, California
This part of DS 781 presents data for bathymetry for several seafloor maps of the Offshore of Point Conception Map Area, California. The vector data file is included in "Bathymetry_OffshorePointConception.zip," which is accessible from https://doi.org/10.5066/F7QN64XQ. These data accompany the pamphlet and map sheets of Johnson, S.Y., Dartnell, P...
CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 ocean-currents projections: 20-year storm in Ventura County
Model-derived ocean current velocities (in meters per second) 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
CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 water-level projections: 100-year storm in Orange County
Model-derived total water levels (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 Souther
Bathymetry hillshade--Offshore of Gaviota Map Area, California
This part of DS 781 presents data for bathymetry for several seafloor maps of the Offshore of Gaviota Map Area, California. The vector data file is included in "BathymetryHS_OffshoreGaviota.zip," which is accessible from https://doi.org/10.5066/F7TH8JWJ. These data accompany the pamphlet and map sheets of Johnson, S.Y., Dartnell, P., Cochrane, G.R...
Faults--Offshore of Gaviota Map Area, California
This part of DS 781 presents fault data for the geologic and geomorphic map of the Offshore of Gaviota map area, California. The vector data file is included in "Faults_OffshoreGaviota.zip," which is accessible from https://doi.org/10.5066/F7TH8JWJ. These data accompany the pamphlet and map sheets of Johnson, S.Y., Dartnell, P., Cochrane, G.R.,...
Reprocessed boomer 3D seismic-reflection data of field activity P-04-11-CC in Estero Bay, offshore of Morro Bay, central California, 2012-08-12 to 2012-10-05
This dataset includes reprocessed boomer 3D seismic data collected by the Fugro Consultants Inc. in 2012, in Estero Bay, offshore of Morro Bay, central California.
CoSMoS (Coastal Storm Modeling System) Southern California v3.0 Phase 2 flood-hazard depth and duration projections: 100-year storm in Orange County
Maximum depth of flooding surface (in cm) in the region landward of the present day shoreline that is inundated for the storm condition and sea-level rise (SLR) scenario indicated. Note: Duration datasets may have occasional gaps in open-coast sections.
The Coastal Storm Modeling System (CoSMoS) makes detailed predictions (meter-scale) over large geographic scales (100s of k
Contour--Offshore of Gaviota Map Area, California
This part of DS 781 presents data for bathymetric contours for several seafloor maps of the Offshore of Gaviota Map Area, California. The vector data file is included in "Contours_OffshoreGaviota.zip," which is accessible from https://doi.org/10.5066/F7TH8JWJ. These data accompany the pamphlet and map sheets of Johnson, S.Y., Dartnell, P.,...
Water pressure/depth, velocity, and turbidity time-series data from SPB14 Bay shallows stations in San Pablo Bay and China Camp Marsh, California
Files contain hydrodynamic and sediment transport data for the location and deployment indicated. Time-series data of water depth, velocity, turbidity, and temperature were collected in San Pablo Bay and China Camp Marsh as part of the San Francisco Bay Marsh Sediment Experiments. Several instruments were deployed in tidal creek, marsh, mudflat, and Bay locations, gathering data on
Time-averaged image from video of beach in Santa Cruz, California
Time-averaged image, or “timex,” created by averaging the intensity of light recorded at each spot, or “pixel,” during a 10-minute video taken at Santa Cruz, California, on May 6, 2017. Blurred white zones show where waves are breaking. Line between wet and dry sand shows the maximum height on the beach reached by the waves (“runup”). Researchers at the USGS are using
...Variance image from video of beach in Santa Cruz, California
“Variance” image produced from video shot at Cowells Beach in Santa Cruz, California, on May 6, 2017. The more the light intensity changes at a given spot, or “pixel,” during the video, the brighter the value assigned to that pixel. Motion tends to produce changes in light intensity. Note bright areas along and beyond the shore where waves were breaking. Researchers are
...An extremely rare Mojave River western pond turtle
An extremely rare Mojave River western pond turtle was recently observed by USGS scientists and staff from The Living Desert Zoo and Gardens in the Mojave Desert. Turtles of this population have rarely been seen since the late 1990s.
Sacramento National Wildlife Refuge, CA
Sacramento National Wildlife Refuge, CA
Hot plate set-up
After mixing about 20 grams of a sediment sample with distilled water, we add strong hydrogen peroxide to break down or "digest" organic matter that may be in the sample. Organic matter makes clay particles stick together and we need them separate in order to calculate accurate particle size fractions of the sample. Digestion takes place overnight. Then we cook off the
...Brazilian waterweed
Tips of Brazilian waterweed (Egeria densa) break the surface at low tide in Lindsey Slough in the northern Sacramento-San Joaquin River Delta. More commonly, this invasive plant is completely submerged.
Establishing Forster's Tern Nesting Colonies
Scientists from the USGS Western Ecological Research Center (WERC) are conducting a "social attraction" study for seabirds in the Don Edwards San Francisco Bay National Wildlife Refuge. Historically, this region offered wetland habitats to local wildlife. With the introduction of industrial salt ponds and human development, however, much of this habitat was lost. Now,
California Wildflower Superbloom, Spring 2017, Landsat 8
After 5 years of drought, California finally got relief during the winter of 2016–2017 with much needed precipitation. One result of this additional moisture was a springtime abundance of wildflowers in 2017. This Landsat 8 image shows a large area of wildflower "superbloom" just north of Los Padres National Forest in southern California.
The Wildflower Superbloom in California from Landsat’s Perspective
After 5 years of drought, California finally got relief during the winter of 2016–2017 with much needed precipitation. One result of this additional moisture was a springtime abundance of wildflowers.
There were many places to see this wildflower “superbloom” in southern California. This pair of images from Landsat
...Recovering instrument package from Monterey Canyon
On March 21, 2017, the sediment trap from this instrument package (deployed the previous October into Monterey Canyon) is gone and the mounting frame is mangled, having been exposed to several significant turbidity currents in one deployment.
Sieving sediment
Washing a sediment sample through two sieves with distilled water lets us measure the fractions of gravel (bigger than 2 millimeters or -1 phi) and sand (2 millimeters to 63 microns, -1 phi to 4 phi). Smaller sediment passes through the sieves into a standard 1-liter graduated cylinder.
Sediment suspension preparation
After adding a little sodium hexametaphosphate dispersant, we use a plunger to carefully stir the cylinder then let it settle, to ensure good mixing and standardized suspension of the sediment.

On May 22, 1915 an explosive volcanic eruption occurred at Lassen Peak, California.
MENLO PARK, Calif. – Members of the news media are invited to attend the U.S. Geological Survey Open House in Menlo Park this weekend. This event includes over 80 exhibits that highlight the work USGS scientists do. Join them in action as they share the excitement of their scientific work and discoveries with the general public.
PORTLAND, Ore.– The U.S. Geological Survey has developed models to help water managers identify strategies to use groundwater for meeting competing water demands in the semi-arid upper Klamath Basin.
MENLO PARK, Calif. – Many Bay Area residents know what it’s like to experience an earthquake, but fewer of them know why earthquakes happen. The concepts behind earthquakes and living safely in earthquake country are as simple as a fishing line hooked to a stack of bricks, explains USGS geophysicist Ross Stein, whose family-friendly seismic demos and models are part of the...
CONTRA COSTA COUNTY, Calif. -- For the first time, scientists have measured the amounts of mercury flowing into the San Francisco estuary from tidal wetlands using a new technique that can measure concentrations of mercury in water every few minutes, which is essential for understanding mercury flows in a complex tidal estuarine environment.
MENLO PARK, Calif. – Education and entertainment await visitors of all ages at the U.S. Geological Survey's Menlo Park Campus Open House on Saturday, May 19 and Sunday, May 20, from 10 a.m. to 4 p.m.
Building an Earthquake Early Warning System for California
SAN DIEGO —Organic solvents were detected at high concentrations in 18 percent of the aquifer system used for public supply in the San Fernando and San Gabriel basins. However, groundwater is not directly used as drinking water; water purveyors may treat groundwater before delivering it to customers to ensure compliance with water quality standards.
MENLO PARK, Calif. Decisions made by the global community about emissions will directly impact the future of the western United States. On March 22nd, Tom Suchanek, U.S. Geological Survey climate change coordinator, will discuss how increasing atmospheric carbon dioxide might affect human land-use and environmental systems in California and the Bay Area.
MENLO PARK, Calif.— The El Mayor-Cucapah earthquake in northern Baja California, Mexico on April 4, 2010 triggered surface movement on several Southern California faults. Detailed mapping of these small movements by the U.S. Geological Survey, California Geological Survey, and other institutions, revealed previously unknown faults in the greater Salton Sea area...
SACRAMENTO, Calif.— Scientists at the U.S. Geological Survey have, for the first time, demonstrated how aquifer composition can affect how excessive levels of phosphorous (an essential nutrient contained in fertilizers) can be carried from fertilized agricultural fields via groundwater to streams and waterways.
Waterfowl in California can spread low pathogenic avian influenza viruses during summertime when wetland temperatures are warm and waterfowl densities are low, according to a recent U.S. Geological Survey study.