Wisconsin Wetlands: Locating Wetlands

NOTE: Although there are many clues that you can use to get a sense of potential wetland areas, determining the legal extent of a wetland for federal or state regulations must be done by professionals trained in wetland boundary delineation.

1. Use existing wetland maps.
2. Review other existing map resources.
3. Review existing soil data.
4. Look for plants and plant communities that indicate wet conditions.
5. Look for evidence of water.

1. Use existing wetland maps.

   Look for mapped wetlands in and near your project area.

   Information Sources:
   • Wisconsin Wetland Inventory
   • The Natural Resources Conservation Service has paper copies of wetland maps available at their county offices (exit DNR)

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2. Review other existing map resources.

   Other maps may also include information about wetlands.

   Information Sources:
   • DNR Surface Water Data Viewer

   The surface water data view can be used to view WISCLAND land cover data, which includes wetlands information. Under “Layers,” select the “Forests & Landcover” folder and check the “WISCLAND Landcover” box.

   

   The surface water data viewer can also be used to find USGS topographic maps and aerial photographs. The USGS maps have topographic lines that show changes in elevation and slope. These maps also show large wetland areas.

   

   Aerial photographs are also available on the surface water data viewer. Look for dark areas that may indicate wet soil conditions. Sometimes wetlands that are dominated by reed canary grass will look white on black and white aerials photos.

   

   • Southeastern Wisconsin Regional Planning Commission Regional Map Server (exit DNR)

     This map server contains some wetland information for southeastern Wisconsin.

   • WiscLINC: Wisconsin Land Information Clearinghouse (exit DNR)

     The geodata catalog provides links to Wisconsin county/city/village GIS and mapping websites.

     Many communities have websites with sophisticated mapping capabilities that show waterways, aerial photographs, wetlands and soil information. Other communities may currently only provide paper maps. Please contact your county or municipality to inquire about what wetland information they have available.

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3. Review existing soil data.

   The Natural Resources Conservation Service has maps that identify areas that contain hydric soils. In laymen’s terms, hydric soils (exit DNR) are soils that exhibit characteristics of being wet over extended periods of time. The presence or absence of hydric soils is a pivotal clue in locating wetlands and wetland restoration opportunities. Directions for obtaining hydric soils information can be found at the NRCS Web Soil Survey (exit DNR).

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4. Look for plants and plant communities that indicate wet conditions.

   There are plant species, such as cattails, that are obvious to most as being wetland plants. However, there are hundreds of plants that normally only grow in wet conditions.

   Information Sources:
   • Wetland Plants and Plant Communities of Minnesota and Wisconsin (exit DNR)
   • Midwestern Wetland Flora (exit DNR)
   • Wisconsin Wetland Types
   • US EPA Wetland Types (exit DNR)

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5. Look for evidence of water.

   This can be the most difficult clue to find and many times there is no evidence of water on or above the surface of the ground. Some wetlands have saturated soils and some are ponded only at certain times of the year. Here are a few examples of visual clues.

   

   Dry cracked surface surrounded by vegetation. This is an indication of standing water for long periods of time.

   

   

   Buttressed tree roots and clumped vegetation. This is an adaptation to be able to live in the wet soil environment.

   

   Stains on vegetation, leaves and structures provide evidence of standing water for long periods of time.

   Non-visual clues of the presence of water include "squishy or soft" ground surface, getting wet feet after standing in area for a period of time, and the smell of sulfur or rotten eggs when you step or dig in the area.

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For assistance in using this website or for additional information on locating wetlands please contact your local Water Management Specialist or U.S. Army Corps of Engineers Project Manager (exit DNR).