Cedar Creek IA 04-RAC-1156

Assessment Comments

Assessment based on 2002 REMAP data: Fish IBI= 44 (fair), BM-IBI= 63 (good) and 1998 evaluated Fisheries data: Fish IBI = 42 (fair).

Basis for Assessment

The assessment was based on data collected in 2002 as part of the DNR/UHL REMAP project and on 1998 data collected by Manchester fisheries.   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 score was 44 (fair) and the BM-IBI score was 63 (good).  The 1998 Fisheries evaluated Fish IBI score was 42 (fair).   The aquatic life use support was assessed as fully supporting/threatened (=FS/T), 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.        

Threats to the continued support of the Class B(LR) uses include over- pasturing of the riparian corridor and channelization in headwater reaches.   Nutrient impacts in this upper (Class B(LR)) reach seem to be less obvious than in the lower (Class B(WW)) reach of Cedar Creek.   A fish kill was reported near Lohrville on August, 16, 1995.  The kill was attributed to natural causes.   No other information is available.