Rock Creek IA 02-CED-493

Assessment Comments

Assessment based on results of IDNR/UHL biological (biocriteria) monitoring in 2001: FIBI = 71 (excellent), BMIBI = 65 (good) and 2002 Fisheries data: FIBI = 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.

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 FIBI score was 71 (excellent) and the BMIBI score was 65 (good).   The 2002 Fisheries FIBI score was 67 (good).   The aquatic life use support was assessed as fully supporting (= FS), based on a comparison of the FIBI and BMIBI scores with biological impairment criteria (BIC) established for previous Section 305(b) reports.  The biological impairment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2004.   The FIBI BIC for this ecoregion is 36 and the BMIBI BIC for this ecoregion is 51.

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