Tuesday, March 3, 2009

MPCA Water Quality Standards - Revised Rule 7050 - 7052

The Minnesota Pollution Control Agency (MPCA) is requesting comments on its planned amendments (“Triennial Review”) to rules governing state water quality standards found in Minnesota Rules Chapters. 7050 and 7052.

- Chapter 7050 includes provisions to protect Minnesota’s waters from pollution.
- Chapter 7052 provides standards specific to surface waters of the state in the Lake Superior Basin.


The Federal Clean Water Act (CWA) requires States to review their water quality standards every three years (“Triennial Review”) and to amend and update them if necessary. The MPCA initiated this triennial review by seeking comments in a Request for Comments published in the July 28, 2008, State Register. The key amendments being considered for the upcoming Triennial Review include:

  • Planned Amendments for Numeric Standards for Class 2 waters
  • Eutrophication standards for river systems.
  • Revised turbidity standards
  • New or revised contaminant standards for protection of aquatic life and human health from toxic effects related to:
    1. Cadmium
    2. Copper
    3. Chloride
    4. Diazinon
    5. Nonylphenol
    6. Nitrate

  • Updates in methods to human health-based chronic water quality standards
  • Amendments to Class 3 (Industrial Consumption) and Class 4 (Agriculture and Wildlife) standards.
  • Potential Water Use Classification Changes for Specific Water Bodies

Caltha LLP provides expert consulting services to public and private sector clients nationwide to address water quality standards, wastewater permitting and assessing potential impacts of chemicals in the aquatic environment.

Caltha LLP Aquatic Toxicology / WQ Standards Services Website