The DNR is coordinating a collaborative effort to update the National Wetlands Inventory (NWI) in Minnesota. The original NWI for Minnesota was created through a U.S. Fish and Wildlife Service program and was based on aerial photographs that primarily date from 1979 to 1984. The NWI is the only spatially comprehensive wetland inventory for Minnesota, but the original maps are now considerably out-of-date. The NWI data are used for fish and wildlife management, land use planning, environmental impact assessment, natural resource inventories and as a preliminary screening tool for wetland regulation. The primary funding source for this effort is the Environmental and Natural Resources Trust Fund.
Public Waters Inventory (PWI) maps show the lakes, rivers, streams and wetlands that are regulated by the DNR under the Public Waters Permit Program.