Bluff Creek TMDL Biological Stressor Identification

In 2004, Bluff Creek was placed on the Minnesota Pollution Control Agency's (MPCA) list of impaired waters in need of a Total Maximum Daily Load (TMDL) study for impaired biota due to low fish Index of Biotic Integrity (IBI) scores. Once water bodies are listed as impaired, stressors causing impairment must be identified, and remediation efforts, including development of total maximum daily loads (TMDL) for identified pollutants, need to be initiated. The Stressor Identification process is a formal method developed by the Environmental Protection Agency (EPA) by which the causes of biological impairment may be identified through a step-by-step procedure. In this process, existing biological, chemical, physical, and land-use data are analyzed to determine probable causes of impairment for aquatic organisms.