Assessment Comments
Assessment is based on results of IDNR/UHL biological (biocriteria) monitoring in 2001: Fish IBI = 17, 19, 16 (all poor); BM-IBI = 65, 71, 70 (all good) and on 2002 Fisheries data: Fish IBI = 24 (poor).
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 2001 and IDNR Fisheries sampling in 2002. This is the same assessment as that developed for the 2002 reporting cycle except for the addtion of the Fisheries data.
EXPLANATION: The assessment was based on data collected in 2001 as part of the DNR/UHL stream biocriteria project and on 2002 Manchester Fisheries stream sampling data. 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 2001 Fish IBI scores were 17 (poor), 19 (poor) and 16 (poor); the BM-IBI scores were 65 (good), 71 (good) and 70 (good). The 2002 Fisheries Fish IBI score was 24 (poor). 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.
