Assessment Comments
Assessment is based on results of IDNR/UHL biological (biocriteria) sampling: Avg.1994 - 1998 Biocriteria scores: Fish IBI=58 (good), BM-IBI=67 (good); the 2000 biocriteria data are Fish IBI= 48 (fair) and BM-IBI= 62 (good).
Basis for Assessment
[Note: For the 2002 report, the previous waterbody segment for White Fox Creek (IA 04-UDM-0220-0), which extended 17 miles from its mouth to confluence with an unnamed tributary in Wright County, was split into two subsegments: (1) mouth to the Hamilton / Wright county line (IA 04-UDM-0220-1) and (2) Hamilton / Wright county line to confluence with unnamed tributary WNW of Big Wall Lake (IA 04-UDM-0220-2). See above for previous Section 305(b) assessments for the original 42-mile river reach.]
SUMMARY: The Class B(LR) aquatic life uses are assessed (monitored) as "fully supported / threatened" (minor impacts) based on results of IDNR/UHL biological (biocriteria) sampling in August 1998; this stream segment was also sampled twelve additional times as part of the IDNR/UHL biocriteria project from 1994 to 1998 in attempt to determine the influence of sampling season (spring, summer, fall) on results of biocriteria monitoring. This is the same assessment as that developed for the 2002 reporting cycle.
EXPLANATION: This assessment was based on data collected in 2000 as part of the DNR/UHL stream biocriteria project. The 2000 Fish IBI score was 48 (fair) and the BM-IBI score was 62 (fair). The aquatic life use support was assessed as fully supporting/threatened (=FST), 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.
The fish and aquatic macroinvertebrates of this stream segment were also sampled twelve times from July 1994 to May 1998 as part of the IDNR/UHL stream biocriteria project. As stated in the assessment developed for the 2000 reporting cycle, the average F-IBI score for samplings over the 1994-1998 period was 58 (good) and the average BM-IBI score was 67 (good). Based on this information, the Class B(LR) aquatic life uses were assessed as fully supported / threatened (=FST), based on a comparison of the F-IBI and BM-IBI scores with biological assessment criteria established specifically for the 2000 Section 305(b) report. The biological assessment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-1998.
