Unnamed Creek (aka Tibbetts Cr) IA 01-MAQ-40

Assessment Comments

Stream use assessment in Jones County.

Basis for Assessment

Used a review of the field sheet from the October 1991 DNR stream use assessment in Jones County to downgrade the assessment of support of the Class B(LR) aquatic life uses due to (1) very low fish community diversity (3 cyprinid species) for streams in the Iowan Surface subecoregion (47c) and (2) presence of less than a majority of the expected fish taxa (2 of 11) for streams in this subregion.  The cause of this low diversity is not apparent from the field sheet: habitat quality is above average due to diverse substrates, numerous pool/riffle sequences, and lack of significant impacts to the physical characteristics of this stream, and field sheet does not indicate problems with seining or other water quality problems.  The data upon which this assessment is based are more than 5 years old.  Follow-up monitoring is needed to update this assessment, to determine the status of the aquatic communities, and to determine the degree to which the Class B(LR) uses may be impaired.