Sixmile Creek IA 06-BSR-1533

Assessment Comments

Assessment is based on occurrence of a fish kill in June 1998 and on two 1991 DNR stream use assessments conducted in Sioux county.

Basis for Assessment

SUMMARY:  The Class B(LR) aquatic life uses were assessed as "partially supported".   EXPLANATION:  The assessment of support of the Class B(LR) uses developed for the previous (1998) report ("partially supported"; see 1998 assessment) was based on results from two DNR stream use assessment conducted in 1991.   The results from these assessments are now considered too old (greater than five years) to be useful for developing water quality assessments of current conditions.   A fish kill occurred on Sixmile Creek on June 15, 1998; no specific location information is available.   This kill was attributed to cattle manure.   An estimated 1,150 fish were killed (an previous fish kill on Sixmile Creek occurred near Hawarden on November 6, 1993; this kill was attributed to the Farmers Coop Society in Sioux Center).   According to DNR's assessment methodology for Section 305(b) reporting, occurrence of a single pollution-caused fish kill within the most recent three-year period (1997-1999) indicates that the aquatic life uses of a waterbody are only "partially supported."  Thus, the assessment of support of the Class B(LR) aquatic life uses of this stream was assessed as "partially supported" due to the June 1998 fish kill.