National Wetland Inventory Update for Minnesota

The National Wetland Inventory (NWI) data for Minnesota are being updated through a multi-agency collaborative effort under leadership of the Minnesota Department of Natural Resources (MNDNR). The update is being conducted in geographic phases with data released for each region as it is finalized. This metadata record covers the first four geographic regions: central, east-central, northeast, and southern Minnesota. Major funding was provided by the Environmental and Natural Resources Trust Fund. The updated NWI classify wetlands according to the system developed by Cowardin et al. (1979). The data also contains a simplified plant community classification (SPCC) and a simplified hydrogeomorphic (HGM) classification. Quality assurance of the data included visual inspection, automated checks for attribute validity and topologic consistency, as well as a formal accuracy assessment based on an independent field verified data set. Further details on the methods employed can be found in the technical procedures document for this project located on the project website (http://www.dnr.state.mn.us/eco/wetlands/nwi_proj.html ). The updated NWI data are primarily based on spring aerial imagery acquired in 2011 and LiDAR elevation data as well as other modern ancillary data. These data are intended to replace the original 1980s NWI data. NWI data support effective wetland management, protection, and restoration. The data provide a baseline for assessing the effectiveness of wetland policies and management actions. These data are used at all levels of government, as well as by private industry and non-profit organizations for wetland regulation and management, land use and conservation planning, environmental impact assessment, and natural resource inventories.<br/><br/>The ESRI File Geodatabase download includes four layer files that classify data with symbology using an attribute field in the base data:<br/>1) NWI Circular 39 Class 2009-2014 (CIRC39_CLASS): The classification system known as Circular 39 is an older classification system developed primarily for the inventory and classification of waterfowl habitat (Shaw and Fredine 1956). Wetlands are classified based on the frequency and depth of inundation as well as vegetation community. This classification system has 20 different wetland types, of which eight (8) are present in Minnesota.<br/>2) NWI Cowardin Class 2009-2014 (COW_CLASS1): The Cowardin system is the primary classification system used by the National Wetland Inventory to describe wetlands and ecologically related deep water habitats. It is a hierarchical classification organized into ecological system, classes, and subclasses. The class and subclass levels are primarily based on plant community or substrate. Beyond this, the system also provides information on water regime and a variety of other special cases.<br/>3) NWI Simplified HGM Class 2009-2014 (HGM_SYMBOL): This Simplified Hydrogeomorphic system classifies wetlands not based on their plant communities, but rather based on their geomorphic setting (i.e. landscape position), water source, and hydrodynamics.<br/>4) NWI Simplified Plant Community Class 2009-2014 (SPCC_DESC): This classification system is based on the Wetland Plants and Plant Communities of Minnesota and Wisconsin (Eggers & Reed 2011). Some of the distinctions between these plant community classes are difficult to reliably assess using aerial imagery data; therefore, for the NWI we have reduced the simplified this system to nine vegetated classes and one non-vegetated class.<br/> <br/> CENTRAL: Operational support for wetland mapping and classification was provided by Ducks Unlimited (DU) and support for methods development and field validation were provided by the Remote Sensing and Geospatial Analysis Laboratory at the University of Minnesota. The DNR Resource Assessment Office provided additional support data processing, field checking, and quality control review. The east-central project area consists of 15 counties including: Aitkin, Beltrami, Benton, Cass, Crow Wing, Hubbard, Itasca, Kanabec, Mille Lacs, Morrison, Pine, Stearns, Todd, Wadena, and a portion of Carlton Counties. The updated wetland inventory area included complete coverage for all USGS quarter quadrangles that intersect any of these counties (about 20,300 square miles).The NWI classification process for east-central Minnesota consisted of three basic steps: 1) creation of image segments (polygons), 2) RandomForest classification of the segments, and 3) photo-interpretation/editing of the classified image segments.<br/> <br/> EAST-CENTRAL: Operational support for wetland mapping and classification was provided by Ducks Unlimited (DU) and support for methods development and field validation were provided by the Remote Sensing and Geospatial Analysis Laboratory at the University of Minnesota. The DNR Resource Assessment Office provided additional support data processing, field checking, and quality control review. The east-central project area consists of 13 counties including: Anoka, Carver, Chisago, Dakota, Goodhue, Hennepin, Isanti, Ramsey, Rice, Scott, Sherburne, Washington, and Wright Counties. The updated wetland inventory area included complete coverage for all USGS quarter quadrangles that intersect any of these counties (about 7,150 square miles).The NWI classification process for east-central Minnesota consisted of three basic steps: 1) creation of image segments (polygons), 2) RandomForest classification of the segments, and 3) photo-interpretation/editing of the classified image segments.<br/><br/> NORTHEAST: Operational support for wetland mapping and classification was provided by Ducks Unlimited (DU) and support for methods development and field validation were provided by the Remote Sensing and Geospatial Analysis Laboratory at the University of Minnesota. The DNR Resource Assessment Office provided additional support data processing, field checking, and quality control review. The project area consists of 5 counties in northeast Minnesota including: Cook, Koochiching, Lake, St. Louis, and a portion of Carlton Counties. The project encompasses 1,097 USGS quarter quads covering an area of 14,330 square miles (17% of the state). The NWI classification process for northeast Minnesota consisted of three basic steps: 1) creation of image segments (polygons), 2) RandomForest classification of the segments, and 3) photo-interpretation of the classified image segments. Please note that a portion of Koochiching County was completed as a separate pilot project. Those data are not yet included in the greater northeast regional product and will be incorporated after their validation is complete.<br/> <br/> SOUTHERN: Operational support for wetland mapping and classification was provided by Geospatial Services of St. Mary's University of Minnesota (SMUMN) and support for methods development and field validation were provided by the Remote Sensing and Geospatial Analysis Laboratory at the University of Minnesota. The MNDNR Resource Assessment Office provided additional support data processing, field checking, and quality control review. Major funding was provided by the Environmental and Natural Resources Trust Fund. The project area consists of 36 counties in southern Minnesota including: Big Stone, Blue Earth, Brown, Chippewa, Cottonwood, Dodge, Faribault, Fillmore, Freeborn, Houston, Jackson, Kandiyohi, Lac qui Parle, Le Sueur, Lincoln, Lyon, Martin, McLeod, Meeker, Mower, Murray, Nicollet, Nobles, Olmstead, Pipestone, Redwood, Renville, Rock, Sibley, Steele, Swift, Wabasha, Waseca, Watonwan, Winona, and Yellow Medicine Counties. The project encompasses 1,787 USGS quarter quads covering an area of 23,900 square miles (28% of the state). The NWI classification process for southern Minnesota relied on visual image interpretation and other geospatial techniques to identify and classify wetlands using remote sensing data. <br/><br/> NOTE: The layer files for this data have been set up to restrict drawing of the data when zoomed out beyond 1:250,000 scale. This is, in part, to prevent problems with slow performance with this large dataset.

Additional Info

Field Value
Last Updated September 22, 2018, 10:02
Created July 29, 2014, 15:04
dsAccessConst None
dsCurrentRef Based on 2009 - 2014 digital aerial photos. Time Period of Content Date indicates when dataset was last updated.
dsMetadataUrl ftp://ftp.gisdata.mn.gov/pub/gdrs/data/pub/us_mn_state_dnr/water_nat_wetlands_inv_2009_2014/metadata/metadata.html
dsModifiedDate 2018-09-22 00:13:03
dsOriginator Minnesota Department of Natural Resources, Ducks Unlimited, and St. Mary's University of Minnesota
dsPeriodOfContent 9/14/2018
dsPurpose The updated NWI data for central, east-central, northeast, and southern MN are primarily based on spring aerial imagery acquired 2009 - 2014 and LiDAR elevation data as well as other modern ancillary data. These data are intended to replace the original 1980s NWI. NWI data support effective wetland management, protection, and restoration. The data provide a baseline for assessing the effectiveness of wetland policies and management actions. These data are used at all levels of government, as well as by private industry and non-profit organizations for wetland regulation and management, land use and conservation planning, environmental impact assessment, and natural resource inventories.

Dataset extent