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Watersheds

A watershed is an area of land that drains all the streams and rainfall to a common outlet such as the outflow of a reservoir, mouth of a bay, or any point along a stream channel. Watersheds can be as small as a footprint or large enough to encompass all the land that drains water into rivers that drain into San Francisco Bay, where it enters the Pacific Ocean. The word "watershed" is sometimes used interchangeably with drainage basin or catchment. Watersheds consist of surface water--lakes, streams, reservoirs, and wetlands--and all the underlying groundwater. 

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Basin Characterization Model (BCM)

The Basin Characterization Model (BCM) is a simple grid-based model that calculates the water balance for any time step or spatial scale by using climate inputs, precipitation, minimum and maximum air temperature. The BCM can translate fine-scale maps of climate trends and projections into the hydrologic consequences, to permit evaluation of the impacts to water availability at regional, watershed...
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Basin Characterization Model (BCM)

The Basin Characterization Model (BCM) is a simple grid-based model that calculates the water balance for any time step or spatial scale by using climate inputs, precipitation, minimum and maximum air temperature. The BCM can translate fine-scale maps of climate trends and projections into the hydrologic consequences, to permit evaluation of the impacts to water availability at regional, watershed...
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Development of Numeric Flow Criteria to Support Freshwater Biological Objectives and Hydrologic Modification Management in California's Wadeable Streams

The State Water Resources Control Board (SWRCB) of California has initiated a process to develop numerical biological objectives for wadeable freshwater streams and rivers for the entire state. Use of biological endpoints for regulatory or compliance purposes requires the ability to relate specific stressors to key biological metrics and to use this understanding to influence management actions...
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Development of Numeric Flow Criteria to Support Freshwater Biological Objectives and Hydrologic Modification Management in California's Wadeable Streams

The State Water Resources Control Board (SWRCB) of California has initiated a process to develop numerical biological objectives for wadeable freshwater streams and rivers for the entire state. Use of biological endpoints for regulatory or compliance purposes requires the ability to relate specific stressors to key biological metrics and to use this understanding to influence management actions...
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Sediment supply, salt marsh monitoring, and the carbon budget of Humboldt Bay, CA

Suspended-sediment measurements are essential for coastal planning, resource management, and for assessing the sustainability of salt marshes in relation to expected sea-level rise. Suspended sediment can have positive or negative effects, depending on its characteristics and amount, and on the location and ecosystem services of interest. Sediment deposition in salt marshes helps sustain marsh...
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Sediment supply, salt marsh monitoring, and the carbon budget of Humboldt Bay, CA

Suspended-sediment measurements are essential for coastal planning, resource management, and for assessing the sustainability of salt marshes in relation to expected sea-level rise. Suspended sediment can have positive or negative effects, depending on its characteristics and amount, and on the location and ecosystem services of interest. Sediment deposition in salt marshes helps sustain marsh...
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Increasing Soil Organic Carbon to Mitigate Greenhouse Gases and Increase Climate Resiliency for California

Rising air temperatures are projected to continue to drive up urban, agricultural, and rangeland water use, straining both surface and groundwater resources. Scientific studies have shown that managing farms, ranches, and public lands to increase soil carbon can increase soil waterholding capacity and increase hydrologic benefits such as increased baseflows and aquifer recharge, reduced flooding...
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Increasing Soil Organic Carbon to Mitigate Greenhouse Gases and Increase Climate Resiliency for California

Rising air temperatures are projected to continue to drive up urban, agricultural, and rangeland water use, straining both surface and groundwater resources. Scientific studies have shown that managing farms, ranches, and public lands to increase soil carbon can increase soil waterholding capacity and increase hydrologic benefits such as increased baseflows and aquifer recharge, reduced flooding...
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Pesticide Fate Research Group (PFRG)

Pesticides are used in both agricultural and urban settings to manage unwanted plants, insects, fungi, and other pests. However, these substances and their breakdown products can move beyond their intended application sites through various means, ending up in areas where they weren't meant to be. This movement can happen via the air, through water (both surface and groundwater), and by sticking to...
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Pesticide Fate Research Group (PFRG)

Pesticides are used in both agricultural and urban settings to manage unwanted plants, insects, fungi, and other pests. However, these substances and their breakdown products can move beyond their intended application sites through various means, ending up in areas where they weren't meant to be. This movement can happen via the air, through water (both surface and groundwater), and by sticking to...
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Assessing Geomorphic Change in Support of Science-Based Restoration, Trinity River, CA

Historic landuse, dam construction, water storage and flow diversion within the Trinity River watershed resulted in downstream geomorphic changes that simplified the river planform and lead to dramatic losses of salmonid habitat and significant population declines. The Trinity River Restoration Program (TRRP) requested the USGS complete an assessment of geomorphic change that could be used to...
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Assessing Geomorphic Change in Support of Science-Based Restoration, Trinity River, CA

Historic landuse, dam construction, water storage and flow diversion within the Trinity River watershed resulted in downstream geomorphic changes that simplified the river planform and lead to dramatic losses of salmonid habitat and significant population declines. The Trinity River Restoration Program (TRRP) requested the USGS complete an assessment of geomorphic change that could be used to...
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Estimating Natural Flows for Hydrologic Reference Streams

Scientists develop metrics of expected hydrological conditions at ungaged sites throughout Callifornia
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Estimating Natural Flows for Hydrologic Reference Streams

Scientists develop metrics of expected hydrological conditions at ungaged sites throughout Callifornia
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