Pomme de Terre River Watershed Biotic Stressor Identification

Stressor Identification analysis is a step-by-step approach for identifying probable causes of impairment in a particular system. There are five stream reaches within the Pomme de Terre River watershed that were identified as impaired for aquatic life based on a lack of biological community. Further evaluation was completed to connect the biological community to the stressor(s) causing the impairment. The objective of this report is to describe the evaluation of the environmental data and the diagnoses of the probable causes for the biological impairments. Numerous candidate causes for impairment were evaluated using U.S. Environmental Protection Agency's (EPA's) Causal Analysis/Diagnosis Decision Information System (CADDIS), Minnesota Pollution Control Agency's (MPCA's) biological Total Maximum Daily Load (TMDL) protocols, and a weight of evidence analysis.