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Hydrologic Extremes

Drought

The USGS monitors the effects of drought through data collection and research of long-term hydrologic, climatic, and environmental changes. These studies support successful planning and science-based decision-making by water managers who must address complex issues and competing interests in times of drought. They also and help decision-makers prepare for climate change and possible future drought.

Flooding

The USGS maintains a network of nearly 500 streamgages in California that delivers a continuous source of streamflow data. When water levels change rapidly, or reach flood-stage levels, flood-warning alerts are issued help emergency managers assess potential hazardous conditions near the gage or for downstream locations.

Wildfires

In an increasingly arid California landscape, wildfires pose significant threat to life, property, and air quality, and have long-term impacts on the state's water. Wildfire can significantly alter the hydrologic response of a watershed to the extent that even modest rainstorms can produce dangerous flash floods and debris flow, and water quality within and downstream from a burn area may be significantly impacted.

Filter Total Items: 43

Emergency Drought Barrier’s Impacts on cyanoHABs and Water Quality

Drought is making the Delta Saltier. Less freshwater coming from watershed runoff and reservoir releases means that more salty water flows into the Sacramento San Joaquin Delta (Delta) from the Pacific Ocean. Changes in Delta salinity have far-reaching impacts, affecting the water supply for agriculture, drinking, wildlife, and Delta ecosystems.
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Emergency Drought Barrier’s Impacts on cyanoHABs and Water Quality

Drought is making the Delta Saltier. Less freshwater coming from watershed runoff and reservoir releases means that more salty water flows into the Sacramento San Joaquin Delta (Delta) from the Pacific Ocean. Changes in Delta salinity have far-reaching impacts, affecting the water supply for agriculture, drinking, wildlife, and Delta ecosystems.
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Salinas Valley Operational Model: Interlake Tunnel and San Antonio Spillway Modification Project

An operational model for Salinas Valley is needed to evaluate and compare ecosystem, conservation, and water demands. This model must simulate current operations, assess benefits of and evaluate scenarios for tunnel operation and potential reservoir and spillway modifications.
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Salinas Valley Operational Model: Interlake Tunnel and San Antonio Spillway Modification Project

An operational model for Salinas Valley is needed to evaluate and compare ecosystem, conservation, and water demands. This model must simulate current operations, assess benefits of and evaluate scenarios for tunnel operation and potential reservoir and spillway modifications.
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California Drought

The USGS closely monitors the effects of drought through data collection and research. USGS science supports water managers in preparing for possible future drought by providing information that takes into account long-term hydrologic, climatic, and environmental changes. These studies support successful planning and science-based decision-making by water managers who must address complex issues...
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California Drought

The USGS closely monitors the effects of drought through data collection and research. USGS science supports water managers in preparing for possible future drought by providing information that takes into account long-term hydrologic, climatic, and environmental changes. These studies support successful planning and science-based decision-making by water managers who must address complex issues...
Learn More

Soil moisture datasets at five sites in the central Sierra Nevada and northern Coast Ranges, California

Soil moisture is a critical variable for understanding the impacts of drought on ecological, hydrological, and agricultural systems, as soil moisture content has a direct affect on runoff amounts. Runoff occurs as the result of precipitation (both rainfall and snowfall) that is in excess of the demands of evaporation from land surfaces, transpiration from vegetation, and infiltration into soils...
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Soil moisture datasets at five sites in the central Sierra Nevada and northern Coast Ranges, California

Soil moisture is a critical variable for understanding the impacts of drought on ecological, hydrological, and agricultural systems, as soil moisture content has a direct affect on runoff amounts. Runoff occurs as the result of precipitation (both rainfall and snowfall) that is in excess of the demands of evaporation from land surfaces, transpiration from vegetation, and infiltration into soils...
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Researching Climate Conditions for CAL FIRE Wildfire Restoration Efforts

In California, drought and warmer climates have increased the prevalence, severity, and duration of wildfires. These fires have destroyed over 129 million trees. In the aftermath of this devastation, there is heightened urgency to increase the capacity of seedling production, particularly for the lower-elevation and private lands that CAL FIRE is responsible to help manage. To support CAL FIRE in...
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Researching Climate Conditions for CAL FIRE Wildfire Restoration Efforts

In California, drought and warmer climates have increased the prevalence, severity, and duration of wildfires. These fires have destroyed over 129 million trees. In the aftermath of this devastation, there is heightened urgency to increase the capacity of seedling production, particularly for the lower-elevation and private lands that CAL FIRE is responsible to help manage. To support CAL FIRE in...
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Basin Characterization Model - Simulating Effects of Iowa Soil Management on Water Availability

As a result of climate change, heavy rainfall, as well as extended dry periods, are becoming more common in the Midwestern United States. These trends are only expected to continue. So, increasing the capacity of soil to store water has become more critical. Storing water increases availability in dry conditions. And the absorption of additional water in wet conditions reduces potential flooding...
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Basin Characterization Model - Simulating Effects of Iowa Soil Management on Water Availability

As a result of climate change, heavy rainfall, as well as extended dry periods, are becoming more common in the Midwestern United States. These trends are only expected to continue. So, increasing the capacity of soil to store water has become more critical. Storing water increases availability in dry conditions. And the absorption of additional water in wet conditions reduces potential flooding...
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Characterizing the Influence of Fire on Hydrology in Southern California

The frequency of fire in southern California forests has steadily increased over time as a result of ignitions at the growing wildland-urban interface, as well as a result of warming due to climate change. Understanding the implications of increased wildfire on hydrologic conditions and water supply is particularly important given the increasing demands for water resources to satisfy growing...
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Characterizing the Influence of Fire on Hydrology in Southern California

The frequency of fire in southern California forests has steadily increased over time as a result of ignitions at the growing wildland-urban interface, as well as a result of warming due to climate change. Understanding the implications of increased wildfire on hydrologic conditions and water supply is particularly important given the increasing demands for water resources to satisfy growing...
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Estimates of soil water deficit during California drought, January 1, 2014: U.S. Geological Survey Data Release

Because the following information has immediate and time-sensitive relevance to public health and welfare owing to the Governor's declared drought emergency it is being released as preliminary information. As preliminary information, it had been reviewed and approved to meet the needs for timely best science, but the methodology is subject to refinement. The information is provided on the...
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Estimates of soil water deficit during California drought, January 1, 2014: U.S. Geological Survey Data Release

Because the following information has immediate and time-sensitive relevance to public health and welfare owing to the Governor's declared drought emergency it is being released as preliminary information. As preliminary information, it had been reviewed and approved to meet the needs for timely best science, but the methodology is subject to refinement. The information is provided on the...
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Characterization of Hydrologic Conditions for Species Distributions Along Environmental Gradients

Plant distributions at local to global scales are influenced by the interplay among plant traits (physiology, anatomy, morphology), the physical setting, biotic interactions, and historical factors such as disturbances and responses to past climate change. Physiological strategies and functional traits provide a key starting point to understand how distributions are shaped along gradients of...
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Characterization of Hydrologic Conditions for Species Distributions Along Environmental Gradients

Plant distributions at local to global scales are influenced by the interplay among plant traits (physiology, anatomy, morphology), the physical setting, biotic interactions, and historical factors such as disturbances and responses to past climate change. Physiological strategies and functional traits provide a key starting point to understand how distributions are shaped along gradients of...
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Climate and Natural Resources Analysis and Planning for California's Northern Coast

The North Coast Resource Partnership (NCRP) is an innovative, stakeholder-driven collaboration among local government, Tribes, watershed groups, and interested partners in the North Coast region of California. The North Coast comprises seven counties, Tribal lands, major watersheds, and a planning area of 19,390 square miles representing 12% of California's landscape. The NCRP integrates long-term...
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Climate and Natural Resources Analysis and Planning for California's Northern Coast

The North Coast Resource Partnership (NCRP) is an innovative, stakeholder-driven collaboration among local government, Tribes, watershed groups, and interested partners in the North Coast region of California. The North Coast comprises seven counties, Tribal lands, major watersheds, and a planning area of 19,390 square miles representing 12% of California's landscape. The NCRP integrates long-term...
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Climate Ready Vulnerability Assessment

To create a framework for adapting to climate change, decision makers need to understand specific threats to our water supply, land use suitability, hazard risks, ecosystems and quality of life. A vulnerability assessment that defines the projected degree to which an ecosystem, landscape, or watershed is vulnerable to change will help to create this framework. Presently those who are open to...
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Climate Ready Vulnerability Assessment

To create a framework for adapting to climate change, decision makers need to understand specific threats to our water supply, land use suitability, hazard risks, ecosystems and quality of life. A vulnerability assessment that defines the projected degree to which an ecosystem, landscape, or watershed is vulnerable to change will help to create this framework. Presently those who are open to...
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Coping with Drought in the Russian River Watershed

Drought in the Russian River region is keyed to the absence of large winter storms-the RR is winter rain-driven, with a few atmospheric river (AR) storms each year bringing 40-50% of the annual rainfall. Two multi-purpose reservoirs provide storage for warm-season uses, and there is little to no snow pack to extend the runoff season. The same ARs that provide beneficial water supply can also cause...
link

Coping with Drought in the Russian River Watershed

Drought in the Russian River region is keyed to the absence of large winter storms-the RR is winter rain-driven, with a few atmospheric river (AR) storms each year bringing 40-50% of the annual rainfall. Two multi-purpose reservoirs provide storage for warm-season uses, and there is little to no snow pack to extend the runoff season. The same ARs that provide beneficial water supply can also cause...
Learn More