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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: 44

Coordinated Pesticide Reconnaissance Study of Surface Waters in California

Pesticides are used throughout the State of California in both urban and agricultural settings and are routinely detected in surface water. Each year, new pesticides are introduced to the market and often become detected in surface water. It can take several years or more for routine monitoring programs to acquire the capability to detect new and understudied pesticides of concern because...
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Coordinated Pesticide Reconnaissance Study of Surface Waters in California

Pesticides are used throughout the State of California in both urban and agricultural settings and are routinely detected in surface water. Each year, new pesticides are introduced to the market and often become detected in surface water. It can take several years or more for routine monitoring programs to acquire the capability to detect new and understudied pesticides of concern because...
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The Effects of Artificial Recharge on Nitrate Concentrations in Groundwater in the Joshua Tree Subbasin, California

The Joshua Basin Water District (JBWD) is implementing an artificial groundwater recharge program to reverse the decline of groundwater levels and to store water in the Joshua Tree groundwater subbasin of the Morongo groundwater basin (~100 mi east of Los Angeles, CA).
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The Effects of Artificial Recharge on Nitrate Concentrations in Groundwater in the Joshua Tree Subbasin, California

The Joshua Basin Water District (JBWD) is implementing an artificial groundwater recharge program to reverse the decline of groundwater levels and to store water in the Joshua Tree groundwater subbasin of the Morongo groundwater basin (~100 mi east of Los Angeles, CA).
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Yucaipa Valley Hydrogeology

This study assesses the quality of water in the Yucaipa area, primarily in the Yucaipa plain. This hydrogeology study will aid local water purveyors in understanding and evaluating local resources and using those resources effectively in combination with water imported from northern California and from the adjacent San Bernardino area.
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Yucaipa Valley Hydrogeology

This study assesses the quality of water in the Yucaipa area, primarily in the Yucaipa plain. This hydrogeology study will aid local water purveyors in understanding and evaluating local resources and using those resources effectively in combination with water imported from northern California and from the adjacent San Bernardino area.
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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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Temecula Hydrogeology

This site provides hydrologic data collected or compiled by the USGS for the Temecula area; some additional data may be available from the USGS database National Water Information System (NWIS) .
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Temecula Hydrogeology

This site provides hydrologic data collected or compiled by the USGS for the Temecula area; some additional data may be available from the USGS database National Water Information System (NWIS) .
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San Bernardino Optimal Basin Management

The San Bernardino area of southern California has complex water-management issues. As an aid to local water managers, this report provides an integrated analysis of the surface-water and ground-water systems, documents ground-water flow and constrained optimization models, and provides seven examples using the models to better understand and manage water resources of the area. As an aid to...
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San Bernardino Optimal Basin Management

The San Bernardino area of southern California has complex water-management issues. As an aid to local water managers, this report provides an integrated analysis of the surface-water and ground-water systems, documents ground-water flow and constrained optimization models, and provides seven examples using the models to better understand and manage water resources of the area. As an aid to...
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Injection, storage, and extraction of water, Roseville, California

The purpose of this study is evaluate how vertical variations in aquifer properties and well hydraulics may affect the injection, storage, and extraction of water and the transport of associated disinfection by-products in the Mehrten Formation underlying the City of Roseville.
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Injection, storage, and extraction of water, Roseville, California

The purpose of this study is evaluate how vertical variations in aquifer properties and well hydraulics may affect the injection, storage, and extraction of water and the transport of associated disinfection by-products in the Mehrten Formation underlying the City of Roseville.
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Sources of Microbial Contamination at Public Beaches, Santa Barbara

The focus of this study is on analysis of existing hydrologic, chemical, and microbiological data; collection of surface-water and shallow ground-water hydrologic, chemical, and microbiological data; and characterization of dissolved organic carbon composition.
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Sources of Microbial Contamination at Public Beaches, Santa Barbara

The focus of this study is on analysis of existing hydrologic, chemical, and microbiological data; collection of surface-water and shallow ground-water hydrologic, chemical, and microbiological data; and characterization of dissolved organic carbon composition.
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