Nutting Creek IA 01-TRK-205

Assessment Comments

Assessment is based on results of IDNR/UHL biological (biocriteria) monitoring in 1999: FIBI = 49 (fair), BMIBI = 56 (good). FIBI BIC = 52, BMIBI BIC = 61.

Basis for Assessment

SUMMARY:  The Class B(LR) aquatic life uses are assessed (evaluated) as "fully supported"  based on results of IDNR/UHL biological (biocriteria) sampling in 1999.   This is an upgrade to the assessment from the 2004 assessment of partial support.   In addition, 2006 biological data (outside of the data window) indicate that this segment is fully supporting its aquatic life uses.  

EXPLANATION:  This assessment was based on data collected in 1999 as part of the DNR/UHL stream biocriteria project.   A series of biological metrics which reflect stream water quality and habitat integrity were calculated from the biocriteria sampling data.   The biological metrics are based on the numbers and types of benthic macroinvertebrate taxa and fish species that were collected in the stream sampling reach.   The biological metrics were combined to make a fish community index of biotic integrity (FIBI) and a benthic macroinvertebrate index (BMIBI).   The indexes rank the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum).   The 1999 FIBI score was 49 (fair) and the BMIBI score was 56 (good).   The aquatic life use support was assessed as partially supporting (=PS), 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 52 and the BMIBI BIC for this ecoregion is 61.