Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Willow Slough IA 05-NSH-1443

Mills County S29T73NR40W 3 mi. SW of Henderson.

Assessment Cycle
2004
Result Period
2000 - 2002
Designations
Assessment Methodology
Assessment Type
Evaluated
Integrated Report
Category 2a
Legacy ADBCode
IA 05-NSH-00820-L_0
Overall Use Support
Threatened
Aquatic Life Use Support
Threatened
Fish Consumption
Not assessed
Documentation
Assessment Comments

Assessment is based on information from the IDNR Wildlife Bureau.

Basis for Assessment

SUMMARY:  The Class B(LW) aquatic life uses remained assessed as "fully supported / threatend" based on information from the IDNR Wildlife Bureau.    Fish consumption uses remain "not assessed."  This is the same assessment as that developed for the 2002 reporting cycle.

EXPLANATION:  Based on a review of the previous (2000) assessment by the DNR Wildlife Bureau, the Class B(LW) aquatic life uses remain assessed as "fully supported / threatened."  The primary threat remains siltation from agricultural nonpoint sources.   According to the local DNR Wildlife Biologist, Willow Slough normally has very good water quality but receives considerable sedimentation due to locally heavy rains.  

Fish consumption uses remain "not assessed" due to the lack of fish contaminant monitoring at this wetland.   In general, Iowa wetlands are not managed for recreational fisheries; thus, fish contaminant monitoring is not typically conducted at these waterbodies.

Monitoring and Methods
Assessment Key Dates
Methods
120 Surveys of fish and game biologists/other professionals
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
Siltation Aquatic Life Support Not Impairing
  • Agriculture
  • Natural Sources
  • Not Impairing
  • Not Impairing