Rock Creek IA 02-CED-493

Assessment Comments

Assessment based on results of IDNR/UHL biological (biocriteria) monitoring in 2001: Fish IBI = 71 (excellent), BM-IBI =64 (good) and 2002 Fisheries data: Fish IBI = 67 (good).

Basis for Assessment

SUMMARY:  The Class B(WW) aquatic life uses are assessed (monitored) as "fully supported"  based on results of IDNR/UHL biological (biocriteria) sampling in 2001 and Fisheries sampling in 2002.   Fish consumption uses remain "not assessed" due to the lack of fish contaminant monitoring in this stream segment.   This is the same assessment as that developed for the 2002 reporting cycle with the addition of the 2002 Fisheries data.

EXPLANATION:  The assessment was based on data collected in 2001 as part of the DNR/UHL stream biocriteria project and on data collected in 2002 as part of a DNR Fisheries stream sampling project: Manchester research station.  The 2001 Fish IBI score was 71 (excellent) and the BM-IBI score was 64 (good).  The 2002 Fisheries Fish IBI score was 67 (good).   The aquatic life use support was assessed as fully supporting (=FS), based on a comparison of the F-IBI and BM-IBI scores with biological assessment criteria established specifically for the 2002 Section 305(b) report.  The biological assessment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2001.

Fish consumption uses remain "not assessed" due to the lack of fish contaminant monitoring in this stream segment