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    • The StreamCat Dataset: Accumulated Attributes for NHDPlusV2 (Version 2.1) Catchments for the Conterminous United States: Index of Watershed Integrity / Index of Catchment Integrity (IWI/ICI)

    Metadata Updated: February 10, 2026

    This dataset represents the Index of Watershed Integrity / Index of Catchment Integrity (IWI/ICI) within individual local NHDPlusV2 catchments and upstream, contributing watersheds based on 23 other StreamCat metrics. The Index of Watershed Integrity (IWI) is based on first order approximations of relationships between stressors and six watershed functions: hydrologic regulation, regulation of water chemistry, sediment regulation, hydrologic connectivity, temperature regulation, and habitat provision. Link to paper: https://doi.org/10.1016/j.ecolind.2017.10.070\nThe Index of Watershed Integrity / Index of Catchment Integrity (IWI/ICI) were summarized to produce local catchment-level and watershed-level metrics as a continuous data type.

    Access & Use Information

    Public: This dataset is intended for public access and use. License: See this page for license information.

    Downloads & Resources

    References

    https://www.epa.gov/national-aquatic-resource-surveys/streamcat-dataset#access-streamcat-data
    https://edg.epa.gov/metadata/catalog/search/resource/details.page?uuid=520397B1-342A-45EA-B8F9-B05694C0A194

    Dates

    Metadata Created Date January 30, 2026
    Metadata Updated Date February 10, 2026
    Data Update Frequency R/P3Y

    Metadata Source

    Harvested from EPA Non Geo Repository

    Other Data Resources

    Additional Metadata

    Resource Type Dataset
    Metadata Created Date January 30, 2026
    Metadata Updated Date February 10, 2026
    Publisher U.S. Environmental Protection Agency, Office of Water,
    Maintainer
    Identifier 520397B1-342A-45EA-B8F9-B05694C0A194
    Data First Published 2015-04-23
    Language en-US
    Data Last Modified 2023-11-13
    Rights public (Data asset is or could be made publicly available to all without restrictions)
    Category environment
    Public Access Level public
    Data Update Frequency R/P3Y
    Bureau Code 020:00
    Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
    Metadata Catalog ID https://edg.epa.gov/data/nongeo_data.json
    Schema Version https://project-open-data.cio.gov/v1.1/schema
    Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
    Data Quality True
    Data Dictionary https://www.epa.gov/national-aquatic-resource-surveys/streamcat-metrics-and-definitions
    Data Dictionary Type text/html
    Harvest Object Id 135bb4ce-0b06-441b-b051-a1b4a5f1b0e2
    Harvest Source Id 9c1c2b5b-7925-4ca2-a663-ca2131653db1
    Harvest Source Title EPA Non Geo Repository
    Homepage URL https://www.epa.gov/national-aquatic-resource-surveys/streamcat-dataset
    License https://edg.epa.gov/EPA_Data_License.html
    Old Spatial -125.0,24.5,-66.5,49.5
    Program Code 020:072
    Related Documents https://www.epa.gov/national-aquatic-resource-surveys/streamcat-dataset#access-streamcat-data, https://edg.epa.gov/metadata/catalog/search/resource/details.page?uuid=520397B1-342A-45EA-B8F9-B05694C0A194
    Source Datajson Identifier True
    Source Hash 28e51b22a5323147c32f998c7821d80bb935181a75c0efcdad083b817e185141
    Source Schema Version 1.1
    Spatial {"type": "Polygon", "coordinates": -125.0, 24.5, -125.0, 49.5, -66.5, 49.5, -66.5, 24.5, -125.0, 24.5}
    Temporal 2015/2030

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