Amendments to Water Quality Standards: Use classification 2 (2021-2022)

The MPCA plans to amend Minnesota Rules chapter 7050, which establishes designated uses for rivers, streams, and lakes. The proposed amendments affect Class 2 (Aquatic Life) designations. The MPCA routinely reviews use designations to ensure that assigned beneficial uses are protective and attainable as defined by the Clean Water Act and Minnesota Rule. As the result of routine monitoring, the MPCA has identified waters where the currently designated beneficial use does not accurately reflect an attainable use. Learn more about the agency's proposed amendments:

PDF icon [DRAFT] Amendments to Aquatic Life (Class 2) Use Designations for Streams (wq-rule4-21aa)

PDF icon Appendix A: Amendments to Aquatic Life (Class 2) Use Designations (wq-rule4-21aa1)

Detailed descriptions of thermal habitat use designation reviews.

The Request for Comments on this rulemaking was published in the State Register on April 5, 2021. A copy of the notice and comments received are available as procedural rulemaking documents.

Procedural rulemaking documents

April 2021

Why update designated uses?

The use designations in this rulemaking were initiated based on routine monitoring and rulemaking by the Minnesota Department of Natural Resources. The most important reason to make these changes is that the designated use for each waterbody needs to be correct and appropriate because it affects many water quality protection and restoration efforts (e.g., assessment, stressor identification, National Pollutant Discharge Elimination System permitting, total maximum daily loads). Assigning the correct beneficial uses to Minnesota’s waters also accurately documents the types and condition of Minnesota’s aquatic resources.  


The draft use designations enhance the protection and maintenance of the biological, chemical, and physical integrity of state water resources by:

  • Establishing protective and attainable designated uses. The proposal assigns beneficial uses that will result in appropriate management actions to maintain or improve aquatic life condition.
  • Assigning beneficial uses to protect high-quality water resources. Draft beneficial uses identify high quality water resources and establish higher biological goals to maintain those conditions.
  • Assigning beneficial uses to appropriately classify modified water resources. These include channelized streams and ditches and will result in achievable goals that are consistent with maintaining existing uses.
  • Documenting existing beneficial uses. The revision records the baseline goal for these waters to ensure their restoration or protection.

Technical support documents


Dates Task(s)
Spring 2020 - Dec. 2020  Development of Technical Support Document
April 5, 2021 Notice of Request for Comments published in the State Register  
Winter 2020 - Fall 2021 Informal Public Engagement
Winter 2020 - Summer 2021 Drafting of Rule Language/Statement of Need and Reasonableness
Fall 2021 publish in the State Register Dual Notice of Intent to Adopt Rules/Public Comment Period  
To be determined Public Information Meeting on Proposed Rule Amendments


  • 3 months after Dual Notice of Intent
  • 6 months after Dual Notice of Intent

Adoption of rules

  • No hearing
  • With a hearing
To be determined U.S. EPA review and approval

MPCA contacts

Questions about aquatic life designated uses: Will Bouchard, 651-757-2333 or

Questions about the rule process or schedule: Mary H. Lynn, 651-233-6735 or