Iowa DNR

Water Quality Assessments

Impaired Waters List

Little Sioux River IA 06-LSR-1570

from Highway 3 (S26, T92N, R40W, Cherokee Co.) to confluence with Waterman Cr. in S26, T94N, R39W, O'Brien Co.

Assessment Cycle
Release Status
Result Period
1994 - 1996
Assessment Type
Integrated Report
Category 0
Legacy ADBCode
IA 06-LSR-0030_1
Overall Use Support
Aquatic Life Use Support
Fish Consumption
Not assessed
Primary Contact Recreation
Assessment Comments

Assessment is based on results of IDNR monthly ambient monitoring near Larrabee in 1993-1995 and IDNR fisheries surveys conducted in Cherokee and O'Brien counties in 1989; sampling by J. Olson and D. Howell.

Basis for Assessment

Based assessment primarily on results of WQ monitoring at the DNR monitoring station approx 4 mi E of Larabee; this station was monitored from October 1993 through September 1995.   Monitoring results show no violations of Class B(WW) WQ criteria for either conventional or toxic contaminants in the 8 samples collected over the October 93 to September 1995 period (=FS).   One of the three non flow-affected samples contained levels of fecal coliform bacteria that exceeded the Class A primary contact water quality criterion (=200 organisms/100 ml).   Due to less than 10 data points for the two year period, evaluate support of the Class A uses as FST.   Results of the 1989 DNR fisheries surveys are probably still valid but are too old (i.e., > 5 years) to be used for making "monitored" Section 305(b) assessments.

Monitoring and Methods
Assessment Key Dates
230 Fixed station physical/chemical (conventional plus toxic pollutants)
330 Fish surveys
Monitoring Levels
Biological 0
Habitat 0
Physical Chemistry 0
Toxic 0
Pathogen Indicators 0
Other Health Indicators 0
Other Aquatic Life Indicators 0
# of Bio Sites 0
BioIntegrity N/A
Causes and Sources of Impairment
Causes Use Support Cause Magnitude Sources Source Magnitude