Amendments to Water Quality Standards: Use classifications 2 and 7

Small stream running through banks of tall green grass past a tree

The Minnesota Pollution Control Agency (MPCA) has adopted amendments to rules governing water quality standards: Class 2 and Class 7 use designations, Minnesota Rules chapter 7050 (see Notice of Adopted Rules in the procedural rulemaking documents section below). The rule amendments are effective June 8, 2020.

The rule amendments affect Class 2 (Aquatic Life) and Class 7 (Limited Resource Value Waters) designated uses for lakes and streams. 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.  

Public hearing

The MPCA held a public hearing on the proposed rule amendments on December 11, 2019. Administrative Law Judge Ann C. O’Reilly conducted the hearing. Following the hearing, a post-hearing comment and rebuttal comment period were held, during which additional written comments on the proposed amendments were submitted to the Office of Administrative Hearings. With the conclusion of the rebuttal comment period on January 8, 2020, the hearing record closed. Administrative Law Judge O’Reilly issued her report on February 1, 2020. The judge’s report is available in the procedural rulemaking documents section below. 

Procedural rulemaking documents

May 2020

Feb. 4, 2020

Jan. 9, 2020

MPCA Rebuttal Response submitted to the OAH

No non-MPCA rebuttal responses were submitted to the OAH.

Jan. 2, 2020

MPCA Post Hearing Comments submitted to the OAH

Non-MPCA Post Hearing Comments submitted to the OAH

Dec. 11, 2019

November 2019

September 2019

September 2018

Why update designated uses?

The use designations in this rulemaking were initiated based on routine monitoring, rulemaking by the Minnesota Department of Natural Resources, and requests by the public. 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. And as part of the cold water reviews, changes to Minn. R. 7050.0420 are needed to modernize the MPCA’s process for designating cold and warm/cool water habitats.


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.
  • Revising rule language to better align rules with MPCA and CWA goals. The revision specifies requirements for designating cold water habitats.
  • 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

MPCA contact

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