The following wetland inventory maps were drafted pursuant to Part 303, Wetlands Protection, of the Natural Resources and Environmental Protection Act, 1994 PA 451, as amended. The wetland inventory maps show potential and approximate locations of wetlands and wetland conditions. It is intended that the inventories be used in planning for development, open space designations, etc. as a way to protect wetland resources. The maps are not intended to be used to determine the specific locations and jurisdictional boundaries of wetlands for regulatory purposes. Only an on-site evaluation performed by the DEQ in accordance with Part 303 can be used for jurisdictional determinations. The DEQ has a Wetland Identification Program to assist property owners with identifying the location of any wetlands on their property and whether the wetlands are regulated.

Wetland inventories for the state were produced on a county-by-county basis, all in the same manner. Inventories were produced by overlaying data from the following sources:

1. The National Wetland Inventory (NWI), conducted by the U.S. Fish and Wildlife Service through interpretation of topographic data and aerial photographs.
2. Land Cover, as mapped by the Michigan Department of Natural Resources' Michigan Resource Inventory System (MIRIS), through interpretation of aerial photographs.
3. Soils, as mapped by the U.S. Department of Agriculture, Natural Resource Conservation Service.

The MIRIS and NWI data are shown as one data layer in dark green on the wetland inventory maps.

The inventories represent existing information that suggests the probability that a wetland may or may not exist in a given area. Areas shown as wetlands, wetland soils, or open water on the map are potential wetlands, and deserve further site investigation to verify if wetlands are actually present. The maps may not identify all potential wetlands in a county. It may show wetlands that are not actually present and it may not show wetlands which are actually present.

Wetland inventory maps for all counties are available in pdf format from the Center for Geographic Information website. 

Paper copies of these wetland inventory maps can be ordered with a Request for Wetland Inventory Maps Form.

The DEQ has certified that all county wetland inventories required by Part 303 were complete as of January 1, 2007.  Now that the wetland inventories are complete, all non-contiguous wetlands over five acres in size are regulated regardless of county population, making permit requirements uniform in all counties, in accordance with the requirements of Part 303. Issuance of the final wetland inventory maps follows the review of preliminary maps which were distributed to local agencies and reviewed at twenty-eight public hearings held throughout the state.