Little Sioux River IA 06-LSR-1565

Assessment Comments

Assessment is based on results of DNR ambient monthly water quality monitoring in 1998 & 1999 near Smithland in Woodbury Co.

Basis for Assessment

SUMMARY:  The Class B(WW) aquatic life uses were assessed as "fully supported."  The fish consumption uses remain "not assessed."  EXPLANATION:  The assessments of the Class B(WW) uses were based on results of monitoring during the 1998-1999 biennial period from the DNR quarterly station on the Little Sioux River northeast of Smithland in Woodbury County.   Based on the lack of violations of Class B(WW) criteria for pH, dissolved oxygen, and ammonia in the eight samples analyzed during the biennial period, and due to the lack of violations of Class B(WW) chronic criteria for toxic metals in the two samples analyzed during this period, the aquatic life uses were assessed as "fully supported."  This assessment was based on results of quarterly monitoring.   Results from stations monitored monthly or more frequently, however, are preferred for Section 305(b) assessments in order to improve the accuracy and confidence level of the assessment.   As part of DNR's expanded water quality monitoring program, monthly monitoring at the Smithland station began in October 1999.   Fish consumption uses remain "not assessed" due to the lack of fish tissue monitoring in this river reach.