Assessment Comments
Assessment is based on results of IDNR/UHL biological (biocriteria) monitoring in 2002: Fish IBI= 54 (good), BM-IBI= 57 (good).
Basis for Assessment
[NOTE: For the 2002 report, the previous waterbody segment for Prairie Creek (IA 04-UDM-0280-0), which extended 9.4 miles from its mouth to the confluence with Drainage Ditch 29 in Webster County, was split into two subsegments: (1) mouth to road crossing in center, Section 28, T88N, R28W, Webster Co. (IA 04-UDM-0280-1) and (2) from road crossing to confluence with Drainage Ditch 29 (IA 04-UDM-0280-2). This split resulted from the addition of the Class A (primary contact recreation) use designation to the lower reach of Prairie Creek in 2001. For more information, see previous Section 305(b) assessments for the original 9.4-mile segment of Prairie Creek.]
SUMMARY: The Class A (primary contact recreation) uses remain "not assessed" due to the lack of information upon which to base an assessment. 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 2002.
EXPLANATION: The Class A designation was added to this segment of Prairie Creek in September 2001; no water quality data or other information are available upon which to base an assessment of support for this use designation.
The Class B(LR) aquatic life assessment was based on data collected in 2002 as part of the DNR/UHL stream biocriteria project. The 2002 Fish IBI score was 54 (good) and the BM-IBI score was 57 (good). 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.
