Statewide Altered Watercourse Project

The Altered Watercourse Project was a joint effort between the Minnesota Pollution Control Agency (MPCA) and Minnesota Geospatial Information Office (MnGeo) to create a statewide inventory of streams that have been hydrologically altered (e.g. channelized, ditched or impounded). The dataset was created to support MPCA's water quality monitoring and assessment program and provides information about stream habitats that have been compromised through such alteration.<br/><br/>The project entailed digitization of Geographic Information System (GIS) 'events' on to the United States Geological Survey's National Hydrography Dataset (NHD) stream linework. The events were then categorized as one of four types: Altered, Natural, Impounded, or No definable channel, based upon a standardized methodology and criteria. These categorizations were performed manually by GIS technicians using visible interpretation of multiple years of aerial photography, LiDAR (Light Detection And Ranging)-based elevation data, and various other reference data in ArcGIS 10.0.<br/><br/>Beginning in 2018, some custom linework was added to the dataset to represent streams that were not present in the NHD. These custom line features do not have a Reachcode, and have a note in the Permanent ID field and the Source Feature ID. These line features will be incorporated into the NHD in the future.<br/>

Additional Info

Field Value
dsAccessConst None
dsCurrentRef Altered Watercourse data is updated annually to reflect changes identified during the Intensive Watershed Monitoring process supporting the surface water assessments. Select HUC8's are reviewed during the assessment, and changes will be based in those HUC8's for a given assessment year.
dsModifiedDate 2023-03-03 00:11:02
dsOriginator Minnesota Geospatial Information Office (MnGeo) for the Minnesota Pollution Control Agency
dsPurpose This project is being conducted in support of the MPCA's water quality monitoring and assessment program. Specifically, the MPCA is developing a refined use designation process known as 'Tiered Aquatic Life Use' (TALU) to account for situations in which stream habitat has been compromised through hydrological alteration. An accurate state-wide determination of altered streams will assist in the assignment of the correct beneficial use within this new TALU framework.
gdrsDsGuid {a8fd2628-9ab4-4f58-a6c6-090a25472961}
spatial {"type":"Polygon","coordinates":[[[-97.23, 43.5],[-97.23, 49.37], [-89.53, 49.37], [-89.53, 43.5], [-97.23, 43.5]]]}

Dataset extent

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