Assessment Comments
Assessment is based on results of IDNR/UHL biological (biocriteria) monitoring in 1997 & 2001 and on 2002 Fisheries data: Fish IBI = 33 (fair).
Basis for Assessment
SUMMARY: The Class B(LR) aquatic life uses are assessed (monitored) as "partially supported" based on results of IDNR/UHL biological (biocriteria) sampling in 1997 and 2001 and 2002 IDNR Fisheries data. This is the same assessment that was developed for the 2002 reporting cycle.
EXPLANATION: This assessment was based on data collected in 1997 and 2001 as part of the IDNR/UHL stream biocriteria project and on data collected in 2002 as part of a IDNR Fisheries stream sampling project: Cold Springs Fish Management. 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 (F-IBI) and a benthic macroinvertebrate index (BM-IBI). The indexes rank the biological integrity of a stream sampling reach on a rising scale from 0 (minimum) to 100 (maximum). The 1997 and 2001 IDNR/UHL Fish IBI scores were 0 (poor) and 0 (poor); the 1997 and 2001 BM-IBI scores were 50 (fair) and 63 (good), respectively. The 2002 IDNR Fisheries evaluated Fish IBI was 33 (fair). The aquatic life use support was assessed as partially supporting (=PS), 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.
