Assessment Comments

Assessment is based on results of IDNR ambient monthly monitoring during 2000 & 2001 near Ackworth.

Basis for Assessment

SUMMARY:  The Class B(LR) aquatic life are assessed (evaluated) as "fully supported / threatened."  The source of data for this assessment is the results of IDNR ambient monthly monitoring during the 2000-2001 biennial period at station 10910003 (formerly station 426046) at the Highway 92 bridge near Ackworth.   EXPLANATION:  The Class B(LR) aquatic life uses were assessed as "fully supported / threatened."  None of the 24 samples collected during the 2000-2001 biennial period at the IDNR monthly station violated Class B(LR) water quality criteria for pH, dissolved oxygen, or ammonia-nitrogen; no violations occurred in the four samples analyzed for toxic metals or in the six samples analyzed for pesticides and other toxic organic compounds.   These results suggest full support of the Class B(LR) aquatic life uses.   Although results of chemical monitoring suggest relatively good water quality and full support of the aquatic life uses of this river segment, previous assessments has indicated potential impacts due to alteration of aquatic habitats (see assessments for previous 305(b) reports above).   Thus, the Class B(WW) aquatic life uses remain assessed (evaluated) as "fully supported /threatened."  Biological monitoring is needed to better define the status of aquatic communities in this river segment.