English River IA 02-IOW-671

Assessment Comments

Assessment is based on results from the IDNR ambient monthly water quality monitoring station near Riverside.

Basis for Assessment

Used results from the DNR monthly WQ monitoring station at Riverside to develop assessments of support of designated uses.   The Class B(WW) aquatic life uses were assessed as FS:  none of the 24 samples collected during the Oct 95-Sep 97 period violated chronic or acute Class B(WW) WQ criteria; one of 24 samples violated the Class B(WW) WQ criterion for dissolved oxygen (2.8 mg/l on February 8, 1996).   Because less than 10% of samples violated this criterion, support of aquatic life uses is assessed as FS (see p.  3-17 of Supplement to the U.S.  EPA Guidelines for Preparation of the 1998 Section 305(b) reports).   Overall support assessed as FST due to known threats from nonpoint source pollution.