Assessment Comments
Stream use assessment in Delaware County.
Basis for Assessment
Used a review of the field sheet from the October 1991 DNR stream use assessment in Delaware County to continue to assess support of the Class B(LR) aquatic life uses as PS due to (1) very low fish community diversity (2 cyprinid species) and (2) presence of only one of the 11 expected fish taxa for streams in the Iowan Surface subecoregion (47c). The field sheet does not indicate potential reasons for this low aquatic diversity other than very shallow conditions: ie, habitat quality is relatively high, with fair diversity of substrates, presence of several pool/riffle sequences, and lack of significant impacts to the physical characteristcs of this stream. The data upon which this assessment is based are more than 5 years old. Follow-up monitoring is needed to update the assessment, to determine the status of the aquatic communities and habitats, and to determine the degree to which the Class B(LR) uses may be impaired.
