Platte River IA 05-PLA-1469

Assessment Comments

Stream use assessment in August 1991. Natural fishkill in August 1995.

Basis for Assessment

Used a review of the field sheet from the August 1991 DNR stream use assessment SW of Creston to upgrade the assessment of support of the Class B(LR) aquatic life uses from FST to FS due to (1) presence of a moderately diverse fish community (11 species from 4 families) for streams in the Missouri River portion of the Southern Iowa Rolling Loess Prairies (47f) subecoregion, (2) presence of all the expected fish taxa (6 of 6) for streams in this region, and (3) indications on the field sheet of good quality aquatic habitats, including servarl pool/riffle sequences, only isolated areas of channel alterations, and very stable stream banks.   This reach is located downstream from the Creston WWTP and a "slight sewage odor" was noticed during the assessment; however, the fish community present did not suggest impairments due to any point source of pollution.  The data upon which this assessment is based is more than 5 years old.   Additional monitoring is needed to update this assessment and to determine the status of the aquatic communities and habitats.   A fish kill occurred on this stream 1.5 miles SSW of Kent in Union County on August 31, 1995.   An estimated 400 fish were killed; the kill was attributed to natural causes, especially low stream flow and high water temperatures.