Middle Raccoon River IA 04-RAC-1190

Assessment Comments

Assessment is based on results of an October 1997 IDNR fish survey.

Basis for Assessment

SUMMARY:  The Class A (primary contact recreation) uses remain "not assessed" due to the lack of information upon which to base an assessment.   The Class B(WW) aquatic life uses remain assessed (evaluated) as "fully supported / threatened" (minor impacts) based on results of an IDNR fish survey in 1997.   Fish consumption uses remain "not assessed."  

EXPLANATION:  The Class A uses remain "not assessed" due to the lack of water quality information for this segment upon which to base an assessment.  

The Class B(WW) aquatic life uses remain assessed as "fully supported / threatened " based on results of the biological monitoring conducted by IDNR on this stream segment in 1997.   As stated in the assessment devleoped for the 2000 reporting cycle, the results from the October 1997 DNR fish survey at Hanging Rock Access at Redfield were used to assess support of the Class B(WW) aquatic life uses as FST due to (1) presence of a very diverse fish community of 19 species from 5 families for streams in the Southern Iowa Rolling Loess Prairies (47f) subecoregion, (2) presence of all the expected fish taxa (8 of 8) for streams in this subregion, (3) presence of the expected game fish species (channel catfish reported as "uncommon" with juveniles and adults present, and smallmouth bass reported as "rare" with only 2 juveniles present)), and (4) presence of above average aquatic habitats for a small river with variety substrate types and current velocities, with some water too deep to sample with a backpack electrofisher.   No threats to continued support of the Class B(WW) uses observed, but stream was only assessed at the upstream boundary of the Class B(WW) reach in a public (park) area.   Additional biological monitoring is needed to better determine the degree to which the Class B(WW) uses are supported.   These data are approximately five years old and, based on the availability of information for only one group (fish) of the two groups (fish and benthic macroinvertebrates) typically used to develop a high-confidence (monitored) assessment, the assessment type for this assessment is changed to "evaluted" (lower-confidence assessment).  

Fish consumption uses remain "not assessed" due to the lack of fish contaminant monitoring in this stream segment.