Assessment Comments
Assessment is based on the results of IDNR/UHL biological (biocriteria) monitoring in 2003: upstream/downstream FIBI = 25 (poor) / 20 (poor), downstream BMIBI = 38 (fair).
Basis for Assessment
SUMMARY: The general aquatic life uses remain assessed (evaluated) as "partially supported" based on the results of IDNR/UHL biological (biocriteria) monitoring in 2003. This is the same basic assessment that was developed for the 2004 report but using updated (2003) biological data. This waterbody segment was included on Iowa's 2002 Section 303(d) list. Due to a change in IDNR's assessment methodology, however, this general use-only reach of Bear Creek will be moved off the Section 303(d) list and placed in Category 3b of the 2004 Integrated Report and will remain in that category for the 2006 report..
EXPLANATION: Results of IDNR/UHL biological monitoring near the Roland wastewater treatment plant in 2003 suggested only "partial support" of the general aquatic life uses. The FIBI score upstream/downstream of the Roland wastewater treatment plant was 25 (poor)/ 20 (poor), and the downstream BMIBI score was 38 (fair). The aquatic life use support status was assessed as partially supporting (= PS), based on a comparison of the FIBI and BMIBI scores with biological impairment criteria (BIC) established from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2004. The FIBI BIC for this ecoregion is 32 and the BMIBI BIC for this ecoregion is 62. Even though this site failed both the FIBI and BMIBI BICs, it is uncertain as to whether or not this segment is meeting the aquatic life criteria because it is a small general use stream and doesn’t fall in the calibrated watershed size.
