Thompson River IA 05-GRA-1354

Assessment Comments

Stream use assessment in 1990.

Basis for Assessment

Used a review of the field sheet from the October 1990 DNR stream use assessment 7 mi E of Greenfield to upgrade the assessement of support of the Class B(LR) aquatic life uses from FST to FS due to (1) presence of a relatively diverse fish community (15 species from 5 families) for streams in the portion of the Southern Iowa Rolling Loess Prairies (47f) subecoregion in the Missouri River basin, (2) presence of all the expected fish taxa (6 of 6) for streams in this region, and (3) lack of any significant threats to the continued support of the Class B(LR) uses as identified on the field sheet for the October 1990 stream use assessment.   As noted above, however, this assessment was conducted near the Class B(LR)/general use boundary and thus is likely not representative of the entire Class B(LR) reach downstream to the confluence with West Branch Creek at the Union/Madison County line.   The data upon which this assessment is based are more than 5 years old.   Additional monitoring is needed to update this assessment and to determine the status of the aquatic communities and habitats of this stream.