Filters: Contacts: Tyler D Johnson (X)
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Invasion by Tamarix (L.) can severely alter riparian areas of the western U.S., which are globally rare ecosystems. The upper Verde River, Arizona, is a relatively free-flowing river and has abundant native riparian vegetation. Tamarix is present on the upper Verde but is a minor component of the vegetation (8% of stems). This study sought to determine whether riparian vegetation characteristics differed between sites where Tamarix was present and sites where Tamarix was absent during the invasion of the upper Verde. We hypothesized that herbaceous understory and woody plant communities would differ between Tamarix present and absent sites. Our hypothesis was generally confirmed, the two types of sites were different....
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Arizona,
Biological Invasions,
Community analysis,
Indicator Species Analysis,
Non-metric Multidimensional Scaling (NMS),
Concentrations of inorganic constituents, dissolved organic carbon (DOC), tritium, per- and polyfluoroalkyl substances (PFAS), volatile organic compounds (VOCs), and pharmaceuticals were measured in groundwater samples collected from 254 wells in 2019 and 2020. Concentrations of inorganic constituents, DOC, VOCs, and pharmaceuticals were measured at the U.S. Geological Survey (USGS) National Water Quality Laboratory in Lakewood, Colorado. Concentrations of tritium were measured at the USGS Tritium Laboratory in Menlo Park, California. Concentrations of PFAS were measured at SGS Laboratory in Orlando, Florida. In addition, several geospatial parameters were determined, including: percentages of selected land uses...
Groundwater quality data were collected in 5,000 wells between 1988-2001 by the National Water-Quality Assessment Project. About 1,500 of these wells were sampled again between 2002-2012 to evaluate decadal changes in groundwater quality. Monitoring wells, domestic supply wells, and some public supply wells were included in this study. All water was collected prior to treatment. Groundwater samples used to evaluate decadal change were collected from networks of wells with similar characteristics. Some networks, consisting of domestic or public supply wells, were used to assess changes in the quality of groundwater used for drinking water supply. Other networks, consisting of monitoring wells, assessed changes in...
The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is implemented by the California State Water Resources Control Board. The U.S. Geological Survey (USGS) is the technical lead for the Priority Basin Project (PBP), one of the components of the GAMA Program. Starting in 2012, GAMA began an assessment of water resources in domestic-supply (shallow) aquifers in California. These aquifers provide water for domestic and small community-supply wells, which are often drilled to shallower depths in the groundwater system than public-supply wells. Domestic-supply aquifers...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: California,
GAMA,
Groundwater,
Priority Basin Project,
United States,
Galvanic corrosion of lead in water distribution systems can occur when lead pipe or lead solder is in contact with a dissimilar metal such as copper. If the source water entering those systems has a relatively elevated chloride-to-sulfate mass ratio (CSMR), the potential for galvanic corrosion to occur is elevated (Gregory 1985; Edwards and Triantafyllidou, 2007), especially in water with low values of alkalinity (Nguyen and others, 2011). Values of CSMR were computed for untreated groundwater samples from 26,631 locations in the United States. Three levels, identified by Nguyen and others (2011), were used to classify CSMR values relative to their potential for promoting galvanic corrosion of lead. The three-level...
The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is implemented by the California State Water Resources Control Board. The U.S. Geological Survey (USGS) is the technical lead for the Priority Basin Project (PBP), one of the components of the GAMA Program. Starting in 2012, GAMA began an assessment of water resources in domestic-supply (shallow) aquifers in California. These domestic-supply aquifers provide water for domestic and small community-supply wells, which are often drilled to shallower depths in the groundwater system than public-supply wells. Domestic-supply...
This dataset provides the estimated number of people using publicly supplied groundwater (PSg) or publicly supplied surface water (PSs) for each county in the conterminous U.S. The county boundaries, the PSg, and the PSs represent the year 2010
Categories: Data;
Tags: United States,
drinking water use,
geoscientificInformation,
groundwater,
public supply water use,
The U.S. Geological Survey collected groundwater samples from 49 wells used for domestic and small system drinking water supplies in Amador, Placer, Sutter, and Sacramento counties, California in 2017. The sites were sampled for the Sacramento Metropolitan (SacMetro) Shallow Aquifer Study Unit of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project’s assessment of the quality of groundwater resources used for domestic and small system drinking water supplies. Domestic and small-system wells are commonly screened at shallower depths than public-supply wells. The SacMetro study unit consisted of three “study areas” corresponding to three...
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Amador County,
California,
Environment,
GAMA,
Groundwater,
The U.S. Geological Survey collected groundwater samples from 38 wells used for domestic and small system drinking water supply in the Coachella Valley of California in 2020. The wells were sampled for the Coachella Valley Basin (CODA) Domestic Aquifer Study Unit of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project’s assessment of the quality of groundwater resources used for domestic and small system drinking water supplies. Coachella Valley is located in the Desert hydrogeologic province (Johnson and Belitz, 2003) and is structurally divided into four subbasins by the San Andreas fault: the Indio subbasin, the Mission Creek subbasin,...
The population using public supply drinking water was mapped in two ways: the census enhanced method (CEM) evenly distributes the population across the census block-group, and the urban land-use enhanced method (ULUEM) distributes the population only to certain urban land use designations in order to more precisely locate public supply users. This dataset consists of the estimated population using public supply surface water distributed across block-groups.
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: United States,
drinking water,
geoscientificInformation,
public supply,
surface water
Evaluating Decadal Changes in Groundwater Quality: Groundwater quality data were collected from 5,000 wells between 1988-2001 by the National Water-Quality Assessment Project. Samples are collected in groups of 20-30 wells with similar characteristics called networks. About 1,500 of these wells in 67 networks were sampled about 10 years later between 2002-2012 (second sampling event) to evaluate decadal changes in groundwater quality. Between 2012 and 2016 (third sampling event), a subset of these networks has been sampled again, allowing additional results to be displayed on the web page: Decadal changes in groundwater quality. This is the third iteration of data added to the website, so this data release is referred...
The 1990 census was the last nationally consistent survey of a home’s source of water, and has not been surveyed since. The associated larger work presents a method for projecting the population dependent on domestic wells for years after 1990, using information from the 1990 census along with population data from subsequent censuses. The method is based on the “domestic ratio” at the census block-group level, defined here as the number of households dependent on domestic wells divided by the total population. Analysis of 1990 data (>220,000 block-groups) indicates that the domestic ratio is a function of the household density. As household density increases, the domestic ratio decreases, once a household density...
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: CDF cumulative distribution function,
United States,
census areas,
data-binning,
domestic well,
The U.S. Geological Survey collected groundwater samples from 71 wells used for domestic and small system drinking water supplies in Stanislaus and Merced counties of California during 2020-2021. The wells were sampled for the Modesto-Turlock-Merced Domestic-Supply Aquifer Study Unit of the State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project’s assessment of the quality of groundwater resources used for domestic and small system drinking water supplies. The study unit was defined by the extent of the Modesto, Turlock, and Merced subbasins of the San Joaquin Valley groundwater basin. The study unit was divided into 62 grid cells and one or more domestic...
Evaluating Decadal Changes in Groundwater Quality: Groundwater quality data were collected from 5,000 wells between 1988-2001 (first sampling event) by the U.S. Geological Survey’s National Water-Quality Assessment Project. Samples are collected in groups of 20-30 wells with similar characteristics called networks. About 1,500 of these wells in 67 networks were sampled about 10 years later between 2002-2012 (second sampling event) to evaluate decadal changes in groundwater quality. Between 2012 and 2014 (third sampling event), a subset of these networks has been sampled again, allowing additional results to be displayed on the web page: Decadal changes in groundwater quality. Changes to this web page are referred...
Evaluating Decadal Changes in Groundwater Quality: Groundwater-quality data were collected from 5,000 wells between 1988-2001 (first decadal sampling event) by the National Water-Quality Assessment Project. Samples are collected in groups of 20-30 wells with similar characteristics called networks. About 1,500 of these wells in 67 networks were sampled again approximately 10 years later between 2002-2012 (second sampling event) to evaluate decadal changes in groundwater quality. Between 2012 and 2020 (third sampling event), a subset of these networks was sampled again, allowing additional results to be displayed on the web page: Decadal changes in groundwater quality (https://nawqatrends.wim.usgs.gov/decadal/)....
The 1990 census was the last nationally consistent survey of a home’s source of water, and has not been surveyed since. The associated larger work presents a method for projecting the population dependent on domestic wells for years after 1990, using information from the 1990 census along with population data from subsequent censuses. The method is based on the “domestic ratio” at the census block-group level, defined here as the number of households dependent on domestic wells divided by the total population. Analysis of 1990 data (>220,000 block-groups) indicates that the domestic ratio is a function of the household density. As household density increases, the domestic ratio decreases, once a household density...
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: CDF cumulative distribution function,
United States,
census areas,
data-binning,
domestic well,
The population using public supply drinking water was mapped in two ways: the census enhanced method (CEM) evenly distributes the population across the census block-group, and the urban land-use enhanced method (ULUEM) distributes the population only to certain urban land use designations in order to more precisely locate public supply users. This dataset consists of the estimated population using public supply groundwater distributed across census block-groups.
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: United States,
drinking water,
geoscientificInformation,
groundwater,
public supply
The U.S. Geological Survey collected groundwater samples from 38 wells used for domestic and small system drinking water supply in the Coachella Valley of California in 2020. The wells were sampled for the Coachella Valley Basin (CODA) Domestic Aquifer Study Unit of the California State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Basin Project’s assessment of the quality of groundwater resources used for domestic and small system drinking water supplies. Coachella Valley is located in the Desert hydrogeologic province (Johnson and Belitz, 2003) and is structurally divided into four subbasins by the San Andreas fault: the Indio subbasin, the Mission Creek subbasin,...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: California,
Coachella Valley,
GAMA,
Groundwater Ambient Monitoring and Assessment Program,
Hydrology,
The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide, comprehensive assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is being implemented by the California State Water Resources Control Board. The USGS is the technical lead for the Priority Basin Project (PBP), one of the components of the GAMA Program. The initial focus of the GAMA Priority Basin Project in 2004 to 2012 was on assessment of water-quality in groundwater resources used for public drinking water supply (Belitz and others, 2003; 2015). Groundwater basins and sub-basins (472 in total) were prioritized based upon a number of factors (Belitz and...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: California,
GAMA,
Groundwater,
Priority Basin Project,
Public supply,
The population using public supply drinking water was mapped in two ways: the census enhanced method (CEM) evenly distributes the population across the census block-group, and the urban land-use enhanced method (ULUEM) distributes the population only to certain urban land use designations in order to more precisely locate public supply users. This dataset consists of the total estimated population using public supply surface water and groundwater combined, distributed using the urban land-use enhanced method.
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: United States,
drinking water,
geoscientificInformation,
public supply,
surface water
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