Assessment Comments

Two stream use assessments in 1991.

Basis for Assessment

Used a review of the field sheets from the two 1991 DNR stream use assessments to upgrade the assessment of support of the Class B(WW) aquatic life uses from PS to FST due to (1) presence of good populations of the expected game fish species (channel catfish) at both locations, with flathead catfish also present at Hawleyville (YOY at both locations, abundant at Hawleyville; adults from 12 to 18" TL at Shambaugh), (2) presence of a majority of the expected fish taxa for streams in the Missouri River portion of the Southern Iowa Rolling Loess Prairies (47f) subecoregion at both locations (4 of 6 at Shambaugh; 6 of 6 at Hawleyville), (3) presence of the typical fish diversity (8 species from 3 families) at Shambaugh to exceptional diversity (15 species from 4 families) at Hawleyville, (4) habitat scores equal to, or better than, the overall median habitat score for DNR stream use asessments conducted from 1990-1995, and (5) lack of violations of Class B(WW) WQ criteria at the DNR quarterly WQ monitoring station near Shambaugh during 1992 and 1993.   Primary threats to continued support of the Class B(WW) uses include impacts of old channelization, streambank erosion, and siltation.