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Wetlands as mapped in Department of State Lands’ approved Local Wetlands Inventories. All wetlands greater than or equal to one-half of an acre and all wetlands identified in a Department of State Lands’ approved wetland delineation report were identified and mapped as polygons with a goal accuracy of +/- 25 feet (prior to 2009) or +/- 5 meters (2009 rules). These wetlands trigger cities and counties to submit a wetland land use notice to the Department for proposed land use activities affecting mapped wetlands and other waters (ORS 215.418 and 227.350).
To acquire the complete GIS dataset for the West Eugene Wetland Conservation Plan Inventory please contact the City of Eugene at euggis@ci.eugene.or.us. The dataset is also available at Eugene’s “Mapping Hub” at https://mapping.eugene-or.gov/.
This data set represents the extent, approximate location and type of wetlands and deepwater habitats in Oregon. 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.
The Oregon Biodiversity Information Center, Institute for Natural Resources, Portland has added select fields from the U.S. Fish and Wildlife Service's Wetlands_Project_Metadata layer (https://www.fws.gov/wetlands/Data/Data-Download.html) to the Oregon NWI dataset, thus providing users with a single dataset in which to find project specific wetlands mapping procedures and information on dates and sources of imagery used to map the wetlands within specific project boundaries.
More Oregon Wetlands (MOW) consists of an edited subset of records from the Oregon Wetlands Cover (2009), including those wetland polygons that were not part of a finalized National Wetlands Inventory project, nor generated as part of a Local Wetland Inventory (as indicated by attribute information in the Data_S_Year and Data_S_Type fields). Overlap between MOW polygons and NWI and LWI polygons may exist.
The MOW dataset includes mapping of individual wetland sites by a variety of federal, state, academic, and nonprofit sources. Because MOW is based on the NWI framework, it represents all wetland categories in the Cowardin classification (Federal Geographic Data Committee. 2013. Classification of wetlands and deepwater habitats of the United States. FGDC-STD-004-2013. Second Edition. Wetlands Subcommittee, Federal Geographic Data Committee and U.S. Fish and Wildlife Service, Washington, DC. <https://www.fgdc.gov/standards/projects/wetlands/nwcs-2013>) that are known to be present and mappable in Oregon. It includes perennially inundated "open water" aquatic habitats such as lacustrine limnetic, riverine (all subsystems), and marine and estuarine intertidal and subtidal. Man-made water features such as industrial detention ponds, log ponds, municipal sewage treatment lagoons, and flooded gravel pits are also included because they are often habitat for wetland biota. Portions of upland riparian areas may also be included where they are intermixed with riverine or palustrine wetlands and cannot be separated at the scale used in original mapping.
Metadata for the MOW feature dataset was imported from the Oregon Wetlands Cover (2009) and edited as needed.