This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the United States and its Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). The National Wetlands Inventory - Version 2, Surface Waters and Wetlands Inventory was derived by retaining the wetland and deepwater polygons that compose the NWI digital wetlands spatial data layer and reintroducing any linear wetland or surface water features that were orphaned from the original NWI hard copy maps by converting them to narrow polygonal features. Additionally, the data are supplemented with hydrography data, buffered to become polygonal features, as a secondary source for any single-line stream features not mapped by the NWI and to complete segmented connections. Wetland mapping conducted in WA, OR, CA, NV and ID after 2012 and most other projects mapped after 2015 were mapped to include all surface water features and are not derived data. The linear hydrography dataset used to derive Version 2 was the U.S. Geological Survey's National Hydrography Dataset (NHD). Specific information on the NHD version used to derive Version 2 and where Version 2 was mapped can be found in the 'comments' field of the Wetlands_Project_Metadata feature class. Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries. Please reference the metadata for contact information.

This data set represents the extent, approximate _location and type of wetlands and deepwater habitats in the United States and its Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979), which represents a biological definition of wetlands and deepwater habitats. There is no attempt to define the limits of proprietary jurisdiction of any Federal, State, or local government, or to establish the geographical scope of the regulatory programs of government agencies. Some wetland habitats may be under represented or excluded in certain areas because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters and also some deepwater reef communities (coral or tuberficid worm reefs). These habitats, because of their depth and water clarity, go undetected by most aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project boundaries, specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries.

This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the United States and its Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). The National Wetlands Inventory - Version 2, Surface Waters and Wetlands Inventory was derived by retaining the wetland and deepwater polygons that compose the NWI digital wetlands spatial data layer and reintroducing any linear wetland or surface water features that were orphaned from the original NWI hard copy maps by converting them to narrow polygonal features. Additionally, the data are supplemented with hydrography data, buffered to become polygonal features, as a secondary source for any single-line stream features not mapped by the NWI and to complete segmented connections. Wetland mapping conducted in WA, OR, CA, NV and ID after 2012 and most other projects mapped after 2015 were mapped to include all surface water features and are not derived data. The linear hydrography dataset used to derive Version 2 was the U.S. Geological Survey's National Hydrography Dataset (NHD). Specific information on the NHD version used to derive Version 2 and where Version 2 was mapped can be found in the 'comments' field of the Wetlands_Project_Metadata feature class. Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries.

Note that due to the quantity and complexity of the data there is scale dependent rendering enabled. The vector data only draws when zoomed in to 1:250,000 map scale or larger. To view the wetlands data at a smaller scale utilize the Wetlands Raster service (https://www.fws.gov/wetlandsmapservice/rest/services/Wetlands_Raster/ImageServer) to display generalized wetlands at all scales.. For specific questions or assistance please email wetlands_team@fws.gov.For more information visit: https://www.fws.gov/wetlands/index.htmlView Wetlands Data on the Wetlands Mapper at: https://www.fws.gov/wetlands/Data/Mapper.htmlWetlands Web Services are available at: https://www.fws.gov/wetlands/Data/Web-Map-Services.htmlWetlands Data available as a KML at: https://www.fws.gov/wetlands/Data/Google-Earth.htmlWetlands Data Downloads available at: https://www.fws.gov/wetlands/Data/Data-Download.htmlWetland Data Standards available at: https://www.fws.gov/wetlands/Data/Data-Standards.htmlWetland Codes available at: https://www.fws.gov/wetlands/Data/Wetland-Codes.htm

Indiana Wetlands from the USFWS NWI as of October 6, 2022 at https://www.fws.gov/node/264847

This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the United States and its Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). The National Wetlands Inventory - Version 2, Surface Waters and Wetlands Inventory was derived by retaining the wetland and deepwater polygons that compose the NWI digital wetlands spatial data layer and reintroducing any linear wetland or surface water features that were orphaned from the original NWI hard copy maps by converting them to narrow polygonal features. Additionally, the data are supplemented with hydrography data, buffered to become polygonal features, as a secondary source for any single-line stream features not mapped by the NWI and to complete segmented connections. Wetland mapping conducted in WA, OR, CA, NV and ID after 2012 and most other projects mapped after 2015 were mapped to include all surface water features and are not derived data. The linear hydrography dataset used to derive Version 2 was the U.S. Geological Survey's National Hydrography Dataset (NHD). Specific information on the NHD version used to derive Version 2 and where Version 2 was mapped can be found in the 'comments' field of the Wetlands_Project_Metadata feature class. Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries.

The NWI 2005 was an update to the original 1978 NWI Layer produced by US Fish and Wildlife Service, and utilized 1998 and 2005 imagery to map wetland loss/change over time. Classification of wetlands is based on the Cowardin Wetland Classification system with a minimum mapping unit of 1/10 acre. Wetland data produced by interpreting aerial imagery and digitizing boundaries in a heads up GIS environment. The most current up to date statewide wetland inventory for Michigan available as of 2020. NWI 2015 update is currently in progress in a partnership between EGLE and Ducks Unlimited, with expected statewide completion in 2025.

Field Name

Descriptions

NWICode

The wetland classification codes are a series of letter and number codes that have been developed to adapt the national wetland classification system to map form. These alpha-numeric codes correspond to the classification nomenclature that best describes a particular wetland habitat. For example, PFO1A = Palustrine (P), Forested (FO), Broad-leaved Deciduous (1), Temporarily Flooded (A).

Acres

Size of the wetland.

WETLAND_TYPE

Written description of the wetland type.

For questions about this content reach out to Jeremy Jones at jonesj28@michigan.gov.

The National Wetlands Inventory (NWI) dataset was downloaded from the US Fish and Wildlife Service website at https://www.fws.gov/wetlands/Data/State-Downloads.html on 05/04/2021. Metadata derives from original NWI database and updated to reflect the date of download. According to website, this layer was updated last October 1st, 2020. This is a clip of all wetlands features within the Westchester County boundary minus all riverines, Long Island Sound, and the Hudson River.This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the United States and its Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). The National Wetlands Inventory - Version 2, Surface Waters and Wetlands Inventory was derived by retaining the wetland and deepwater polygons that compose the NWI digital wetlands spatial data layer and reintroducing any linear wetland or surface water features that were orphaned from the original NWI hard copy maps by converting them to narrow polygonal features. Additionally, the data are supplemented with hydrography data, buffered to become polygonal features, as a secondary source for any single-line stream features not mapped by the NWI and to complete segmented connections. Wetland mapping conducted in WA, OR, CA, NV and ID after 2012 and most other projects mapped after 2015 were mapped to include all surface water features and are not derived data. The linear hydrography dataset used to derive Version 2 was the U.S. Geological Survey's National Hydrography Dataset (NHD). Specific information on the NHD version used to derive Version 2 and where Version 2 was mapped can be found in the 'comments' field of the Wetlands_Project_Metadata feature class. Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries.

(Link to Metadata) VCGI downloaded NWI quads from the US FWS web site and reprojected to VCS NAD83. NWI digital data files are records of wetlands location and classification as developed by the U.S. Fish & Wildlife Service. This dataset is one of a series available in 7.5 minute by 7.5 minute blocks containing ground planimetric coordinates of wetlands point, line, and polygon features and wetlands attributes. When completed, the series will provide coverage for all of the contiguous United States, Hawaii, Alaska, and U.S. protectorates in the Pacific and Caribbean. Coverage includes both digital data and hardcopy maps. The NWI maps do not show all wetlands since the maps are derived from aerial photointerpretation with varying limitations due to scale, photo quality, inventory techniques, and other factors. Consequently, the maps tend to show wetlands that are readily photointerpreted given consideration of photo and map scale. In general, the older NWI maps prepared from 1970s-era black and white photography (1:80,000 scale) tend to be very conservative, with many forested and drier-end emergent wetlands (e.g., wet meadows) not mapped. Maps derived from color infrared photography tend to yield more accurate results except when this photography was captured during a dry year, making wetland identification equally difficult. Proper use of NWI maps therefore requires knowledge of the inherent limitations of this mapping. It is suggested that users also consult other information to aid in wetland detection, such as U.S. Department of Agriculture soil survey reports and other wetland maps that may have been produced by state and local governments, and not rely solely on NWI maps. See section on "Completeness_Report" for more information. Also see an article in the National Wetlands Newsletter (March-April 1997; Vol. 19/2, pp. 5-12) entitled "NWI Maps: What They Tell Us" (a free copy of this article can be ordered from U.S. Fish and Wildlife Service, ES-NWI, 300 Westgate Center Drive, Hadley, MA 01035, telephone, 413-253-8620).

Wetlands Wetlands provide a multitude of ecological, economic and social benefits. They provide habitat for fish, wildlife and plants - many of which have a commercial or recreational value - recharge groundwater, reduce flooding, provide clean drinking water, offer food and fiber, and support cultural and recreational activities. Unfortunately, over half of America’s wetlands have been lost since 1780, and wetland losses continue today. This highlights the urgent need for geospatial information on wetland extent, type, and change. The National Wetlands Inventory The US Fish and Wildlife Service (FWS) is the principal US Federal agency tasked with providing information to the public on the status and trends of our Nation's wetlands. The US FWS National Wetlands Inventory (NWI) is a publicly available resource that provides detailed information on the abundance, characteristics, and distribution of US wetlands. NWI data are used by natural resource managers, within the US FWS and throughout the Nation, to promote the understanding, conservation and restoration of wetlands. Resources in this dataset:Resource Title: National Wetlands Inventory. File Name: Web Page, url: https://www.fws.gov/program/national-wetlands-inventory

NWI digital data files are records of wetlands location and classification as defined by the U.S. Fish & Wildlife Service. This dataset is one of a series available in 7.5 minute by 7.5 minute blocks containing ground planimetric coordinates of wetlands point, line, and area features and wetlands attributes. When completed, the series will provide coverage for all of the contiguous United States, Hawaii, Alaska, and U.S. protectorates in the Pacific and Caribbean. The digital data as well as the hard copy maps that were used as the source for the digital data are produced and distributed by the U.S. Fish & Wildlife Service's National Wetlands Inventory project. The data provide consultants, planners, and resource managers with information on wetland location and type. The data were collected to meet U.S. Fish & Wildlife Service's mandate to map the wetland and deep-water habitats of the United States.The full Kansas geospatial catalog is administered by the Kansas Data Access & Support Center (DASC) and can be found at the following URL: https://hub.kansasgis.org/

This data set is a Status Map that identifies the location of wetland data and no data areas. The wetland data itself represents the extent, approximate location and type of wetlands and deepwater habitats in the United States and its Trust Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). Certain wetland habitats may be excluded because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition.The U.S. Fish and Wildlife Service (Service) is the principal Federal agency that provides information to the public on the extent and status of the Nation's wetlands. The Service's strategic plan for our vast national wetland data holdings is focused on the development, updating, and dissemination of wetlands data and information to Service resource managers and the public. The development of the Wetlands Master Geodatabase is in direct response to the need to integrate digital map data with other resource information to produce timely and relevant management and decision support tools.For more information visit: https://www.fws.gov/wetlands/index.htmlView Wetlands Data on the Wetlands Mapper at: https://www.fws.gov/wetlands/Data/Mapper.htmlWetlands Web Services are available at: https://www.fws.gov/wetlands/Data/Web-Map-Services.htmlWetlands Data available as a KML at: https://www.fws.gov/wetlands/Data/Google-Earth.htmlWetlands Data Downloads available at: https://www.fws.gov/wetlands/Data/Data-Download.htmlWetland Data Standards available at: https://www.fws.gov/wetlands/Data/Data-Standards.html

This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the United States and its Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). The National Wetlands Inventory - Version 2, Surface Waters and Wetlands Inventory was derived by retaining the wetland and deepwater polygons that compose the NWI digital wetlands spatial data layer and reintroducing any linear wetland or surface water features that were orphaned from the original NWI hard copy maps by converting them to narrow polygonal features. Additionally, the data are supplemented with hydrography data, buffered to become polygonal features, as a secondary source for any single-line stream features not mapped by the NWI and to complete segmented connections. Wetland mapping conducted in WA, OR, CA, NV and ID after 2012 and most other projects mapped after 2015 were mapped to include all surface water features and are not derived data. The linear hydrography dataset used to derive Version 2 was the U.S. Geological Survey's National Hydrography Dataset (NHD). Specific information on the NHD version used to derive Version 2 and where Version 2 was mapped can be found in the 'comments' field of the Wetlands_Project_Metadata feature class. Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries.

National Wetlands Inventory map showing wetlands within Scott County.

This dataset contains the National Wetland Inventory lines as digitized from the final 1:24,000 NWI map sheets

Digital wetlands data are intended for use with base maps and digital aerial photography at a scale of 1:12,000 or smaller. Due to the scale, the primary intended use is for regional and watershed data display and analysis, rather than specific project data analysis. The map products were neither designed nor intended to represent legal or regulatory products. Due to the quantity and complexity of the wetlands data the wetlands only display at 1:250,000 scale and greater. For wetland information visit: https://www.fws.gov/program/national-wetlands-inventoryView Dataset on the Gateway

This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the United States and its Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). The National Wetlands Inventory - Version 2, Surface Waters and Wetlands Inventory was derived by retaining the wetland and deepwater polygons that compose the NWI digital wetlands spatial data layer and reintroducing any linear wetland or surface water features that were orphaned from the original NWI hard copy maps by converting them to narrow polygonal features. Additionally, the data are supplemented with hydrography data, buffered to become polygonal features, as a secondary source for any single-line stream features not mapped by the NWI and to complete segmented connections. Wetland mapping conducted in WA, OR, CA, NV and ID after 2012 and most other projects mapped after 2015 were mapped to include all surface water features and are not derived data. The linear hydrography dataset used to derive Version 2 was the U.S. Geological Survey's National Hydrography Dataset (NHD). Specific information on the NHD version used to derive Version 2 and where Version 2 was mapped can be found in the 'comments' field of the Wetlands_Project_Metadata feature class. Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries.

This is a MD iMAP hosted service layer. Find more information at http://imap.maryland.gov. This data set represents the extent - approximate location and type of wetlands and deepwater habitats in the conterminous United States. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats - because of their depth - go undetected by aerial imagery. By policy - the Service also excludes certain types of farmed wetlands"" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. Last Updated: Feature Service Layer Link: https://mdgeodata.md.gov/imap/rest/services/Hydrology/MD_Wetlands/MapServer ADDITIONAL LICENSE TERMS: The Spatial Data and the information therein (collectively the ""Data"") is provided "as is" without warranty of any kind either expressed implied or statutory. The user assumes the entire risk as to quality and performance of the Data. No guarantee of accuracy is granted nor is any responsibility for reliance thereon assumed. In no event shall the State of Maryland be liable for direct indirect incidental consequential or special damages of any kind. The State of Maryland does not accept liability for any damages or misrepresentation caused by inaccuracies in the Data or as a result to changes to the Data nor is there responsibility assumed to maintain the Data in any manner or form. The Data can be freely distributed as long as the metadata entry is not modified or deleted. Any data derived from the Data must acknowledge the State of Maryland in the metadata.

Wetlands identified by the National Wetlands Inventory within Stark County, Ohio. This layer was originally downloaded in May, 2019, from https://www.fws.gov/wetlands/Data/Data-Download.html and clipped to the Stark County boundary. This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the United States and its Territories. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). The National Wetlands Inventory - Version 2, Surface Waters and Wetlands Inventory was derived by retaining the wetland and deepwater polygons that compose the NWI digital wetlands spatial data layer and reintroducing any linear wetland or surface water features that were orphaned from the original NWI hard copy maps by converting them to narrow polygonal features. Additionally, the data are supplemented with hydrography data, buffered to become polygonal features, as a secondary source for any single-line stream features not mapped by the NWI and to complete segmented connections. Wetland mapping conducted in WA, OR, CA, NV and ID after 2012 and most other projects mapped after 2015 were mapped to include all surface water features and are not derived data. The linear hydrography dataset used to derive Version 2 was the U.S. Geological Survey's National Hydrography Dataset (NHD). Specific information on the NHD version used to derive Version 2 and where Version 2 was mapped can be found in the 'comments' field of the Wetlands_Project_Metadata feature class. Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries.

This wetland mapping project was funded by the King County Water and Land Services, Ecological Restoration and Engineering Services Unit, as part of a Best Available Science update. Wetlands within the King County boundary were mapped and classified, and reviewed by King County team members and National Wetland Inventory Staff. Wetlands were mapped and classified using: the National Wetlands Inventory (NWI) classification system (Cowardin et al., 1979) and the Landscape Position, Landform, Water Flow Path, and Water Body Type (LLWW) classification developed for the Western U.S. (Lemly et al. 2018).

The main objective for this project was to improve the knowledge of wetland extent and value within King County. In all, more than approximately 6,600 square miles of land comprise the county. King County contracted with Geospatial Services (GSS) at Saint Mary's University of Minnesota to create of high-quality National Wetlands Inventory Plus (NWIPlus) level mapping for the county. Program staff will conduct some ground truthing of data. NWIPlus is an enhanced NWI product with hydrogeomorphic-type descriptors that can facilitate predicting wetland functions. The enhanced attributes describe wetland landform, water flow path and water body type. The updated mapping will be utilized by developers and landowners to avoid wetland impacts, and may be incorporated into other GIS models which would identify potential wetland restoration projects and conservation priorities. Finalized mapping was made available through the county’s online map applications and submitted to the US Fish and Wildlife Service for addition to the National Wetlands Inventory.

King County completed this work as part of a Landscape Level 1 wetlands assessment. This work fits into the counties Wetland Program Plan (“The Plan”) and its goal of providing greater projection of wetlands and aquatic resources statewide. This work is overseen and is supported by the King County Wetland Program, within the Water and Land Services Department. The project, entitled “King County Wetland Inventory Update, King County, WA ” used geospatial techniques and image interpretation processes to remotely map and classify wetlands (includes deepwater habitats) and riparian areas in King County, WA. Wetlands for the project area were mapped and classified using on-screen digitizing methods in a Geographical Information System (GIS). This process was supported by development of a selective image interpretation key that resulted from field verification of image signatures and wetland classifications. Wetland image interpretation employed a variety of input image and collateral data sources, as well as field verification techniques. All mapping was completed at an on-screen scale of 1:5,000 or larger in compliance with national wetland mapping standards. The primary source imagery for mapping consisted of Eagleview, 2021, one-quarter foot, true-color pictometry. 8-bit, tiled orthophotography in TIFF format published by King County and mosaiced by GSS. Collateral data used in the mapping process included Light Detection and Ranging (LiDAR) Digital Elevation Model (DEM) 1.5 ft resolution and LiDAR derived products such as hillshade, contours, depth grids, and synthetic flow networks; King County Digital Surface Model Vegetation Height; King County Coho intrinsic potential stream layer; Beaver Intrinsic Potential (BIP); Historic National Wetland Inventory (NWI); National Hydrography Dataset (NHD) springs and watershed boundaries; ESRI basemap imagery; and Google Earth Time Slider True Color Imagery (GE); King County wetland layers; King County Stormwater features; King County wetland mitigation sites; King County Habitat Restoration sites; and Wetland Intrinsic Potential (WIP). All feature creation and attribution were completed with on-screen digitization procedures using ESRI, ArcGIS Pro 3.2.0 with advanced editing tools. For wetland mapping and classification projects at the landscape level, a desktop computer heads-up digitizing process is performed referencing the Federal Geographic Data Committee (FGDC) Wetlands Mapping Standard (FGDC-STD-015-2009, FGDC 2009) and the FGDC Classification of Wetlands and Deepwater Habitats of the United States Standard (FGDC-STD-004-2013, FGDC 2013). Field reviews are used to address questions regarding image interpretation, land use practices, classification of wetland type and verification of preliminary mapping. The King County inventory of wetlands used source imagery and collateral data to identify and classify features within the FGDC Standards (FGDC-STD-015-2009, FGDC 2009; FGDC-STD-004-2013, FGDC 2013). The projects Target Mapping Unit was 0.25 acres; however, features mapped beyond this TMU by request of King County and at the interpreters discretion. Following this process, the King County inventory went through a standardized Quality Assurance and Quality Control (QA/QC) process with the United States Fish and Wildlife Service (USFWS) NWI program, King County, and GSS’s internal QAQC review.