Public Waters Inventory Update Project

By Jean Meiners

Technician, Root River SWCD

Public waters are all water basins and watercourses that meet the criteria set forth in Minnesota Statute, Section 103G.005, subd. 15, and include lakes, wetlands and watercourses of certain sizes and characteristics. A 2024 statute revision clarified that public waters are not determined by their inclusion in or exclusion from the Public Waters Inventory (PWI). The DNR has been directed to update the PWI over the next eight years. The PWI update will provide better water resource protection and a shared understanding for landowners, local governments and the public at large.

The PWI is the result of a 1979 directive for the DNR to assemble county maps and lists of water bodies in Minnesota that met the statutory definition in Minnesota Statute 103G.005 of “public waters.” The original PWI was completed in the mid-1980s.

The presence of a public water carries benefits and obligations for riparian landowners. Public waters are held in trust by the state for the benefit of all Minnesotans. As such, the DNR is charged under state law with regulating activities within public waters to ensure the public’s collective interest in those waters is protected.

The PWI is also used to determine buffer requirements under the Buffer Law. Minnesota’s Buffer Law requires perennial vegetation buffers of up to 50 feet along rivers, streams and ditches that help filter out phosphorus, nitrogen and sediment. 

The DNR is authorized to change the PWI under certain conditions, one of which is to make corrections. The PWI update will remove waterbodies that are on the inventory that don’t meet the statutory definition and add waterbodies that are not on the inventory that do meet the statutory definition.

The DNR is currently developing the process that will be used to update the PWI. Although the process is not finalized, key aspects of the project will include:

• Assembling a team of hydrologists to use the best available technology, within the time constraints of the project, to conduct technical analysis of needed PWI corrections.
• Proceeding county by county, with the goal of completing an average of 12 counties a year (adjusting, as appropriate, for county size and number of public waters). The specific counties and order of county updates has not been determined.
• Providing preliminary corrections for each county, with opportunity for review, questions and comments. A public meeting will be held in each county, to share and discuss preliminary corrections. Any comments received will be considered prior to finalization of PWI corrections for that county.