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Groundwater Quality

Every day, millions of gallons of groundwater are pumped to supply drinking water for almost one-half of the Nation’s population. Groundwater is also critical to agriculture, one of California's main economic drivers. The California Water Science Center studies aquifers throughout the state that are critical sources of groundwater used for public supply. This research informs us about the quality and availability of groundwater for drinking, where and why groundwater quality is degraded, and where groundwater quality is changing.

Filter Total Items: 43

Evaluating the Geohydrology in the San Gorgonio Pass Area

The San Gorgonio Pass, in southern California, is located between the San Bernardino and San Jacinto Mountain ranges. The mountain ranges to either side of the pass rise almost 9,000 feet (2,700 meters) above. The San Gorgonio Pass serves as a corridor for U.S. Interstate 10. It is also known for its strong winds that make it a popular spot for wind turbine energy production.
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Evaluating the Geohydrology in the San Gorgonio Pass Area

The San Gorgonio Pass, in southern California, is located between the San Bernardino and San Jacinto Mountain ranges. The mountain ranges to either side of the pass rise almost 9,000 feet (2,700 meters) above. The San Gorgonio Pass serves as a corridor for U.S. Interstate 10. It is also known for its strong winds that make it a popular spot for wind turbine energy production.
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Forecasting Total Dissolved Solids Concentrations of Groundwater from the Lower Colorado Water Supply Project

The USGS seeks to increase understanding of the groundwater system in the vicinity of the Lower Colorado Water Supply Project well field and to estimate future groundwater levels and total dissolved solids concentrations in the wells and the long-term viability of the Lower Colorado Water Supply Project.
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Forecasting Total Dissolved Solids Concentrations of Groundwater from the Lower Colorado Water Supply Project

The USGS seeks to increase understanding of the groundwater system in the vicinity of the Lower Colorado Water Supply Project well field and to estimate future groundwater levels and total dissolved solids concentrations in the wells and the long-term viability of the Lower Colorado Water Supply Project.
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Developing Spatial Data on Mineral Deposits Found on Abandoned Mine Lands

Better understanding of mineral deposits and their impact on the environment, including the water system, is necessary for the protection of public health. The USGS is working with other federal and state agencies to identify the environmental behavior of these deposits and their waste products. USGS scientists are using geospatial data (data that can be mapped) to prioritize abandoned mine land...
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Developing Spatial Data on Mineral Deposits Found on Abandoned Mine Lands

Better understanding of mineral deposits and their impact on the environment, including the water system, is necessary for the protection of public health. The USGS is working with other federal and state agencies to identify the environmental behavior of these deposits and their waste products. USGS scientists are using geospatial data (data that can be mapped) to prioritize abandoned mine land...
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San Diego Hydrogeology

This is the first comprehensive geologic and hydrologic study for the San Diego area. This study will provide the integrated hydrogeologic knowledge necessary in this important and highly visible area of the United States and will serve as a role model for similar coastal settings throughout the world that have modest rainfall and small aquifers. Locally, results will help state and federal...
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San Diego Hydrogeology

This is the first comprehensive geologic and hydrologic study for the San Diego area. This study will provide the integrated hydrogeologic knowledge necessary in this important and highly visible area of the United States and will serve as a role model for similar coastal settings throughout the world that have modest rainfall and small aquifers. Locally, results will help state and federal...
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Groundwater Ambient Monitoring & Assessment (GAMA)

The Groundwater Ambient Monitoring and Assessment Program’s Priority Basin Project (GAMA-PBP) was established by the California State Water Resources Control Board (SWRCB) in response to the Ground-Water Quality Monitoring Act of 2001 (Sections 10780-10782.3 of the California Water Code). The USGS is the technical lead for the GAMA-PBP and between 2004-2012 focused on characterizing the quality of...
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Groundwater Ambient Monitoring & Assessment (GAMA)

The Groundwater Ambient Monitoring and Assessment Program’s Priority Basin Project (GAMA-PBP) was established by the California State Water Resources Control Board (SWRCB) in response to the Ground-Water Quality Monitoring Act of 2001 (Sections 10780-10782.3 of the California Water Code). The USGS is the technical lead for the GAMA-PBP and between 2004-2012 focused on characterizing the quality of...
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Groundwater Age

The age of groundwater is key in predicting which contaminants it might contain. There are many tracers and techniques that allow us to estimate the age—or mix of ages—of the groundwater we depend on as a drinking water supply.
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Groundwater Age

The age of groundwater is key in predicting which contaminants it might contain. There are many tracers and techniques that allow us to estimate the age—or mix of ages—of the groundwater we depend on as a drinking water supply.
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Salinas and Carmel River Basins Study

Together, the Salinas and Carmel river basins include some of the world’s most fertile agricultural lands and are internationally known for their natural beauty; ecological diversity; multi-national cultural history; and recreation opportunities such as fishing, auto racing, and golfing. The area is oftentimes referred to as the “Salad Bowl of the World” or “America’s Salad Bowl” because of the...
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Salinas and Carmel River Basins Study

Together, the Salinas and Carmel river basins include some of the world’s most fertile agricultural lands and are internationally known for their natural beauty; ecological diversity; multi-national cultural history; and recreation opportunities such as fishing, auto racing, and golfing. The area is oftentimes referred to as the “Salad Bowl of the World” or “America’s Salad Bowl” because of the...
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Salinas and Carmel Rivers Basin Study: Paso Robles Model Update

The existing Paso Robles Basin Model (PRBM) needed to be updated and enhanced to achieve the timeline and objectives of the Salinas Carmel River Basin Study (SCRBS) for the U.S. Bureau of Reclamation (Reclamation) and local partners.
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Salinas and Carmel Rivers Basin Study: Paso Robles Model Update

The existing Paso Robles Basin Model (PRBM) needed to be updated and enhanced to achieve the timeline and objectives of the Salinas Carmel River Basin Study (SCRBS) for the U.S. Bureau of Reclamation (Reclamation) and local partners.
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SGMApy: An open source platform for computing sustainability metrics and visualizing MODFLOW data

Climate change and demographic changes have underscored the need to improve effectiveness of managing valuable water resources for sustainability. In 2014, the Sustainable Groundwater Management Act (SGMA) established a framework for sustainable, local groundwater management. SGMA requires groundwater-dependent regions to halt overdraft and bring basins into balanced levels of pumping and recharge...
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SGMApy: An open source platform for computing sustainability metrics and visualizing MODFLOW data

Climate change and demographic changes have underscored the need to improve effectiveness of managing valuable water resources for sustainability. In 2014, the Sustainable Groundwater Management Act (SGMA) established a framework for sustainable, local groundwater management. SGMA requires groundwater-dependent regions to halt overdraft and bring basins into balanced levels of pumping and recharge...
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Pajaro Valley Hydrologic Model Update, Data Collection, and Analysis for Sustainability

The Pajaro Valley is home to a billion-dollar agricultural industry, providing food and food processing services for the nation. The water for these enterprises is supplied, in large part, by the groundwater resources (aquifers) in the area. The Pajaro Valley Water Management Agency (PV Water) and the USGS have partnered to improve aquifer monitoring software, allowing better quantification and...
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Pajaro Valley Hydrologic Model Update, Data Collection, and Analysis for Sustainability

The Pajaro Valley is home to a billion-dollar agricultural industry, providing food and food processing services for the nation. The water for these enterprises is supplied, in large part, by the groundwater resources (aquifers) in the area. The Pajaro Valley Water Management Agency (PV Water) and the USGS have partnered to improve aquifer monitoring software, allowing better quantification and...
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Cuyama Valley Water Availability Study

Currently, groundwater is the only source for domestic, agricultural and municipal water use in the Cuyama Valley groundwater basin in Santa Barbara County, California. Groundwater withdrawals, mainly to irrigate agricultural crops, have resulted in water-level declines of as much as 300 feet in the area since the 1940s. To plan for sustainable future use of the groundwater, the U.S. Geological...
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Cuyama Valley Water Availability Study

Currently, groundwater is the only source for domestic, agricultural and municipal water use in the Cuyama Valley groundwater basin in Santa Barbara County, California. Groundwater withdrawals, mainly to irrigate agricultural crops, have resulted in water-level declines of as much as 300 feet in the area since the 1940s. To plan for sustainable future use of the groundwater, the U.S. Geological...
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Borrego Valley Groundwater Conditions

Groundwater is effectively the sole source of water supply for Borrego Valley, California. By the mid-2000s, agriculture, recreation (predominantly golf courses), municipal uses, and the Anza-Borrego Desert State Park required about four times more water than is available through natural recharge. As a result, the U.S. Geological Survey began a cooperative study of the Borrego Valley with the...
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Borrego Valley Groundwater Conditions

Groundwater is effectively the sole source of water supply for Borrego Valley, California. By the mid-2000s, agriculture, recreation (predominantly golf courses), municipal uses, and the Anza-Borrego Desert State Park required about four times more water than is available through natural recharge. As a result, the U.S. Geological Survey began a cooperative study of the Borrego Valley with the...
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