Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Silver Creek IA 01-TRK-192

mouth (S16 T94N R5W Clayton Co.) to confluence with unnamed tributary in S32 T95N R5W Clayton Co.

Assessment Cycle
1998
Result Period
1994 - 1996
Designations
Assessment Type
Evaluated
Integrated Report
Category 0
Legacy ADBCode
IA 01-TRK-0381_0
Overall Use Support
Partial
Aquatic Life Use Support
Partial
Documentation
Assessment Comments

1991 stream use assessment in Clayton County. Fish surveys conducted for UHL study in 1988.

Basis for Assessment

Used a review of the UHL report "A Survey of the Benthic Macroinvertebrates and Fishes of the Big Spring Basin, Iowa" (UHL Report 88-9) to assess support of the Class B(LR) aquatic life uses as PS due to (1) indications of problems with fish kills due to a creamery near Monona (see page 21), and (2) results of fish sampling that show very low fish community diversity for streams in the Driftless Area ecoregion and presence of very few of the expected fish taxa for streams in this region.   The data upon which this assessment is based are approximately 10 years old and thus are of questionable utility for developing an assessment of use support.   These data, however, suggest that follow-up monitoring should be conducted to determine the status of the aquatic communities of this stream and to determine whether the Class B(LR) uses might be impaired.

Monitoring and Methods
Assessment Key Dates
Methods
150 Monitoring data more than 5 years old
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
Organic enrichment/Low DO Overall Use Support Moderate
  • Agriculture
  • Grazing related Sources
  • Municipal Point Sources
  • Pasture grazing - Riparian
  • Moderate
  • Moderate
  • Moderate
  • Moderate
Organic enrichment/Low DO Aquatic Life Support Moderate
  • Agriculture
  • Grazing related Sources
  • Municipal Point Sources
  • Pasture grazing - Riparian
  • Moderate
  • Moderate
  • Moderate
  • Moderate
Other habitat alterations Overall Use Support Moderate
  • Agriculture
  • Grazing related Sources
  • Habitat Modification (other than Hydromodification)
  • Pasture grazing - Riparian
  • Removal of Riparian Vegetation
  • Moderate
  • Moderate
  • Moderate
  • Moderate
  • Moderate
Other habitat alterations Aquatic Life Support Moderate
  • Agriculture
  • Grazing related Sources
  • Habitat Modification (other than Hydromodification)
  • Pasture grazing - Riparian
  • Removal of Riparian Vegetation
  • Moderate
  • Moderate
  • Moderate
  • Moderate
  • Moderate
Siltation Overall Use Support Moderate
  • Agriculture
  • Grazing related Sources
  • Habitat Modification (other than Hydromodification)
  • Pasture grazing - Riparian
  • Removal of Riparian Vegetation
  • Moderate
  • Moderate
  • Moderate
  • Moderate
  • Moderate
Siltation Aquatic Life Support Moderate
  • Agriculture
  • Grazing related Sources
  • Habitat Modification (other than Hydromodification)
  • Pasture grazing - Riparian
  • Removal of Riparian Vegetation
  • Moderate
  • Moderate
  • Moderate
  • Moderate
  • Moderate