Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Buck Creek IA 01-MAQ-45

mouth (S11 T87N R4W Delaware Co.) to Golden Branch in S11 T87N R5W Delaware Co.

Assessment Cycle
2000
Result Period
1996 - 1998
Designations
Assessment Type
Evaluated
Integrated Report
Category 0
Legacy ADBCode
IA 01-MAQ-0210_0
Overall Use Support
Partial
Aquatic Life Use Support
Partial
Documentation
Assessment Comments

Fish kill July 20, 1998.

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 ("fully supported / threatened"; see above) was based primarily on results from a DNR stream use assessment conducted in 1991.   The results from this assessment 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 an unnamed tributary to Buck Creek near Ryan in Delaware County on July 20, 1998.   The kill proceeded down the unnamed tributary for approximately four miles into the upper reaches of the Class B(LR) portion of this stream.   The kill was attributed to runoff of animal waste from a dairy operation; an estimated 92,400 fish were killed.   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 was assessed as "partially supported" due to this fish kill.

Monitoring and Methods
Assessment Key Dates
9/30/1999 Fixed Monitoring End Date
7/20/1998 Fishkill
9/30/1984 Fixed Monitoring Start Date
Methods
120 Surveys of fish and game biologists/other professionals
140 Incidence of spills and/or fish kills
220 Non-fixed station physical/chemical monitoring (conventional pollutant only)
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
Flow alteration Overall Use Support Moderate
  • Source Unknown
  • Moderate
Flow alteration Aquatic Life Support Moderate
  • Source Unknown
  • Moderate
Nutrients Overall Use Support Moderate
  • Source Unknown
  • Moderate
Nutrients Aquatic Life Support Moderate
  • Source Unknown
  • Moderate
Other habitat alterations Overall Use Support Moderate
  • Source Unknown
  • Moderate
Other habitat alterations Aquatic Life Support Moderate
  • Source Unknown
  • Moderate
Siltation Overall Use Support Moderate
  • Source Unknown
  • Moderate
Siltation Aquatic Life Support Moderate
  • Source Unknown
  • Moderate