Assessment Comments
Assessment is based on results of IDNR/UHL biological (biocriteria) sampling in 1994: Fish IBI= 33(fair), 28 (fair), BM-IBI= 67(good), 59(good).
Basis for Assessment
[Note: For the 2002 report, the previous waterbody segment for the West Nishnabotna River (IA 05-NSH-0090-2), which extended 30 miles from the West Fork West Nishnabotna R. at Harlan to an unnamed tributary NE of Manning in Carroll Co., was split into three subsegments: (1) West Fork West Nishnabotna R. to Elk Creek at Irwin (IA 05-NSH-0090-2), (2) Elk Creek to the Crawford-Carroll county line (IA 05-NSH-0090-3), and (3) Crawford-Carroll county line to the unnamed tributary NE of Manning (IA 05-NSH-0090-4). See above for previous Section 305(b) assessments for the original 30-mile stream segment.]
SUMMARY: The Class B(LR) aquatic life uses remain assessed as "fully supported / threatened" based on results of biological monitoring and habitat assessment conducted as part of IDNR/UHL biocriteria monitoring in 1994. Due to the age of these data, the assessment category is changed from "monitored" (higher-confidence assessment) to "evaluated" (lower confidence assessment). This assessment is the same as that developed for the 2002 reporting cycle.
EXPLANATION: Continue to use the assessment developed for the 1998 and 2000 reporting cycles that was based on results of the 1994 IDNR biocriteria assessment conducted approximatey 2.5 miles NNE of Kirkman in Shelby County. Because these data are now considered too old (greater than five years) to accurately characterize current water quality conditions, the assessment category is changed from "monitored" (indicating an assessment with relatively high confidence) to "evaluated" (indicating an assessment with relatively low confidence).
