Assessment Comments
Assessment is based on results of a September 1994 IDNR stream use assessment.
Basis for Assessment
SUMMARY: The Class B(LR) aquatic life uses remain assessed as "partially supported" based on results of biological monitoring and habitat assessment conducted as part of the September 1994 IDNR stream use assessment. Due to the age of these data, the assessment category is changed from "monitored" (higher-confidence assessment) to "evaluated" (lower-confidence assessment).
EXPLANATION: Continue to use the assessment developed for the 1998 and 2000 reporting cycles that was based on results of the 1994 IDNR stream use assessment. As stated in the assessment developed for the 1998 reporting cycle, the Class B(LR) uses were assessed as "partially supported" due to (1) very low fish community diversity (4 species from 2 families) for streams in the Des Moines Lobe subecoregion and (2) presence of less than a majority of the expected fish taxa (2 of 11) for streams in this subregion. Although the sampling of the fish community was negatively affected by large rocks and other debris in the stream, the low diversity suggests that follow-up monitoring should be conducted to better determine the status of the aquatic communities and habitats and to determine whether the Class B(LR) aquatic life uses are impaired. The field sheet did not indicate any significant impacts to the physical characteristics of this stream. Because these data are now considered too old (greater than five years) to accurately characterize current water quality conditions, the assessment category is changed from "monitored" (indicating an assessment with relatively high confidence) to "evaluated" (indicating an assessment with relatively low confidence). Follow-up monitoring is still needed in this stream reach to determine the status of aquatic communities and habitats and to determine the degree to which the Class B(LR) uses may be impaired.
