East Otter Creek IA 02-CED-515

Assessment Comments

Assessment is based on results of (1) IDNR/UHL biological (REMAP) monitoring in 2002 (Fish IBI= 46 (fair), 57 (good); BM-IBI= 77 (excellent)); (2) fish surveys conducted by DNR Fisheries Bureau in 1996, and (3) fish surveys conducted by students from Cornell College in 1997.

Basis for Assessment

SUMMARY:  The Class B(LR) aquatic life uses remain assessed as "fully supported" based primarily on results of IDNR/UHL biological (REMAP) monitoring in 2002.   Results of fish surveys conducted in IDNR Fisheries in 1996 and by Cornell College students in 1997 are also conisidered in this assessment.  

EXPLANATION:  The assessment of the Class B(LR) aquatic life uses was based on data collected in 2002 as part of the IDNR/UHL REMAP 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 (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 2002 Fish IBI scores were 46 (fair), 57 (good) and the BM-IBI score was 77 (excellent).  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 for previous Section 305(b) reports.  The biological assessment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2001.   This assessment is consistent with results of biological monitoring conducted on this stream segment by IDNR Fisheries and Cornell College students in 1996 and 1997, repectively (see assessments developed for the 1998 and 2000 reporting cycles).