Assessment Comments
Assessment is based on 2002 DNR/UHL REMAP data: FIBI = 36 (fair), BMIBI = 43 (fair). FIBI BIC = 43, BMIBI BIC = 54.
Basis for Assessment
SUMMARY: For the 2006 reporting period, the assessment of Class B(LR) aquatic life uses remain assessed as "partially supporting" (PS). The assessment segment includes data collected in 2002 as part of the DNR/UHL stream REMAP project. The 2002 FIBI score was 36 (fair) and the BMIBI score was 43 (fair). The segment was assessed as partially supporting (= PS) based on a comparison of the FIBI and BMIBI scores with biological impairment criteria (BIC) established for previous Section 305(b) reports. The biological impairment criteria were determined from a statistical analysis of data collected at stream ecoregion reference sites from 1994-2004. The FIBI BIC for this ecoregion is 43 and the BMIBI BIC for this ecoregion is 54.
EXPLANATION: The 2006 assessment relies on more recent (2002) sample data collected from a different (upstream) area of the assessment segment than the reference site located in this segment. This area exhibited degraded physical habitat and water quality conditions compared with stream reference site conditions. Elevated levels of total phosphorus, TSS, and turbidity were found in two summer base flow water samples. Seston (water column) chlorophyll a, and high estimated rates of gross primary production and community respiration were indicative of a nutrient/organically-enriched environment. Several types of physical habitat alteration were evident, including removal (grazing) of riparian vegetation, bank destabilization, channel widening, and excessive sediment deposition.
