San Francisco Bay-Delta
The Bay-Delta is a nexus for challenging issues about water, ecosystems, and human use. USGS science helps address key problems and uncertainties.
The Bay-Delta is a nexus for challenging issues about water, ecosystems, and human use. USGS science helps address key problems and uncertainties.
Grand Canyon Monitoring and Research Center
How does Glen Canyon Dam affect downstream Colorado River resources?
How does Glen Canyon Dam affect downstream Colorado River resources?
Lake Tahoe
An underwater view of periphyton growing on rocks near the shore of Lake Tahoe with a reflection of the rocks on the water surface
An underwater view of periphyton growing on rocks near the shore of Lake Tahoe with a reflection of the rocks on the water surface
Salton Sea
The Salton Sea is facing many challenges as inflows and water levels decline. USGS science helps identify problems and evaluate possible solutions.
The Salton Sea is facing many challenges as inflows and water levels decline. USGS science helps identify problems and evaluate possible solutions.
New Technologies for Mapping Surface Soil Moisture
Coastal Dwellers
Southwest Region
The Southwest Region covers Arizona, California, Nevada, and a portion of southern Oregon. Our scientists do a broad array of research and technical assistance throughout the U.S. and across the globe. The Regional Office, headquartered in Sacramento, provides Center oversight & support, facilitates internal & external collaborations, and works to further USGS strategic science direction.
News
RAMPS Newsletter - 2026
RAMPS Newsletter - 2026
Media Alert: Low-level flights to image geology of southern Colorado
Media Alert: Low-level flights to image geology of southern Colorado
Lithium in Eastern States Could Replace Imports for a Century or More
Lithium in Eastern States Could Replace Imports for a Century or More
Publications
Invasion resistance varies by fuel break type in sagebrush ecosystems Invasion resistance varies by fuel break type in sagebrush ecosystems
Background Wildfire is an increasingly important driver of changes within sagebrush (Artemisia spp. L.) ecosystems of the western USA, often resulting in increased spread of exotic annual grasses, such as cheatgrass (Bromus tectorum L.), and subsequent losses of native vegetation and wildlife habitat. Fuel breaks— areas of land treated to reduce or redistribute fuel loads — are widely...
Precipitation timing mediates life-stage and population-level associations with climate for an indicator species Precipitation timing mediates life-stage and population-level associations with climate for an indicator species
Global climate change is contributing to declines in biodiversity, although changes vary across geographic regions and species. The iconic greater sage-grouse (Centrocercus urophasianus; sage-grouse) is central to conservation within the North American sagebrush ecosystem, yet its vulnerability to climate effects remains poorly understood. We used hierarchical models to explore weather...
Imperiled Great Basin terminal lakes: Synthesizing ecological and hydrological science gaps and research needs for waterbird conservation Imperiled Great Basin terminal lakes: Synthesizing ecological and hydrological science gaps and research needs for waterbird conservation
Terminal lakes are declining globally because of human water demands, drought, and climate change. Through literature synthesis and feedback from the resource and conservation community, we review the state of research for terminal lakes in the Great Basin of the United States, which support millions of waterbirds annually, to prioritize ecological and hydrologic information needs. From...
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Ecosystems Mission Area, Water Resources Mission Area, Species Management Research Program, Water Availability and Use Science Program, Forest and Rangeland Ecosystem Science Center, Fort Collins Science Center, Nevada Water Science Center, Oregon Water Science Center, Utah Water Science Center, Western Ecological Research Center (WERC), Saline Lake Ecosystems Integrated Water Availability Assessment
Science
Water Quality
The USGS, in partnership with multiple other groups, is learning about water-quality conditions across time and space in terminal lakes across the Great Basin. This effort is part of the Saline Lake Ecosystems Integrated Water Availability Assessment.
Copper mining, critical minerals, and long-term drought in the Southwest United States
Long-term drought in the Southwest U.S. affects water use across many sectors as well as the natural environment. The Southwest U.S. is an important area for mining porphyry copper deposits, which consist of copper minerals disseminated in breccia, a type of rock composed of coarse rock fragments held together by cement or a fine-grained matrix, that are the World's largest source of copper...
USGS Sagebrush Science: Supporting Public Safety and Economic Decision Making Across the West
The sagebrush biome is one of the largest ecosystems in North America. Encompassing nearly one-third of the continental U.S., it provides critical resources for millions of Americans and a home for hundreds of plants and animal species in the West. Natural resource management in sagebrush ecosystems can be complex, and science can support management decisions by providing knowledge and tools to...
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Core Science Systems Mission Area, Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Climate Adaptation Science Centers, Cooperative Research Units, Land Management Research Program, Species Management Research Program, Earth Resources Observation and Science (EROS) Center, Forest and Rangeland Ecosystem Science Center, Fort Collins Science Center, Northern Rocky Mountain Science Center, Southwest Biological Science Center, Western Ecological Research Center (WERC), Wildland Fire Science