Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Simpson Creek IA 01-TRK-214

mouth (S30 T95NR10W Fayette Co.) to headwaters in S36 T96N R12W Chickasaw Co.

Assessment Cycle
2002
Result Period
1998 - 2000
Designations
Assessment Methodology
Assessment Type
Evaluated
Integrated Report
Category 0
Legacy ADBCode
IA 01-TRK-0445_0
Overall Use Support
Partial
Aquatic Life Use Support
Partial
Documentation
Assessment Comments

Assessment is based on occurrence of fish kill in July 2001. See attached document for details.

Basis for Assessment

The general aquatic life uses are assessed (evaluated) as "partially supported" due to occurrence of a fish kill.   EXPLANATION:  A fish kill occurred on this stream reach on July 23, 2001.   The kill affected approximately 4 miles of Simpson Creek in Sections 16, 17, 21, 22, and 27 of T95N, R11W, Chickasaw Co.   The kill was caused by discharge of hog manure; an estimated 32,700 fish were killed.   According to DNR's assessment methodology for Section 305(b) reporting, occurrence of a single pollution-caused fish kill during the most recent three-year period indicates "partial support" of the aquatic life uses.   Thus, the general aquatic life uses of this stream were assessed as "partially supported."

Monitoring and Methods
Assessment Key Dates
7/23/2001 Fishkill
Methods
140 Incidence of spills and/or fish kills
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
  • Intensive Animal Feeding Operations
  • Moderate
Organic enrichment/Low DO Aquatic Life Support Moderate
  • Intensive Animal Feeding Operations
  • Moderate
Unionized Ammonia Overall Use Support Moderate
  • Intensive Animal Feeding Operations
  • Moderate
Unionized Ammonia Aquatic Life Support Moderate
  • Intensive Animal Feeding Operations
  • Moderate