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Comparison of potential drinking water source contamination across one hundred U.S. cities.

ABSTRACT: Drinking water supplies of cities are exposed to potential contamination arising from land use and other anthropogenic activities in local and distal source watersheds. Because water quality sampling surveys are often piecemeal, regionally inconsistent, and incomplete with respect to unregulated contaminants, the United States lacks a detailed comparison of potential source water contamination across all of its large cities. Here we combine national-scale geospatial datasets with hydrologic simulations to compute two metrics representing potential contamination of water supplies from point and nonpoint sources for over a hundred U.S. cities. We reveal enormous diversity in anthropogenic activities across watersheds with corresponding disparities in the potential contamination of drinking water supplies to cities. Approximately 5% of large cities rely on water that is composed primarily of runoff from non-pristine lands (e.g., agriculture, residential, industrial), while four-fifths of all large cities that withdraw surface water are exposed to treated wastewater in their supplies.

SUBMITTER: Turner SWD

PROVIDER: S-EPMC8669013 | biostudies-literature | 2021 Dec

REPOSITORIES: biostudies-literature

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Comparison of potential drinking water source contamination across one hundred U.S. cities.

Turner Sean W D SWD Rice Jennie S JS Nelson Kristian D KD Vernon Chris R CR McManamay Ryan R Dickson Kerim K Marston Landon L

Nature communications 20211213 1

Drinking water supplies of cities are exposed to potential contamination arising from land use and other anthropogenic activities in local and distal source watersheds. Because water quality sampling surveys are often piecemeal, regionally inconsistent, and incomplete with respect to unregulated contaminants, the United States lacks a detailed comparison of potential source water contamination across all of its large cities. Here we combine national-scale geospatial datasets with hydrologic simu ...[more]

PMID: 34903744

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Dataset Information

Comparison of potential drinking water source contamination across one hundred U.S. cities.

Publications

Comparison of potential drinking water source contamination across one hundred U.S. cities.

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