Iowa DNR
Iowa DNR
ADBNet
Water Quality Assessments
Impaired Waters List

Mariposa Lake IA 03-NSK-867

Jasper County S32T81NR18W 6 mi. NE of Newton.

Assessment Cycle
2000
Result Period
1996 - 1998
Designations
Assessment Methodology
Assessment Type
Monitored
Integrated Report
Category 0
Trophic
Hypereutrophic
Trend
Stable
Legacy ADBCode
IA 03-NSK-00350-L_0
Overall Use Support
Partial
Aquatic Life Use Support
Partial
Fish Consumption
Not assessed
Primary Contact Recreation
Not assessed
Documentation
Assessment Comments

Assessment is based on results of water quality monitoring and surveys by IDNR Fisheries Bureau.

Basis for Assessment

SUMMARY:  The Class A (primary contact recreation) uses were considered "not assessed."  The Class B(LW) aquatic life uses were assessed as "partially supported."  Fish consumption uses were "not assessed."  EXPLANATION:  The Class A uses were considered "not assessed" due to lack of information on levels of indicator bacteria at this lake.   Based on the recommendation of the DNR Fisheries Bureau, the Class B(LW) uses remained assessed as "partially supported."  The water quality trend for this lake was changed from "declining" to "stable."  According to the DNR Fisheries Bureau, this lake experienced severe blooms of algae in 1999.   The fish consumption use remain "not assessed" due to lack of fish tissue monitoring at this lake.

Monitoring and Methods
Assessment Key Dates
Methods
340 Primary producer surveys (phytoplankton/periphyton/macrophyton)
120 Surveys of fish and game biologists/other professionals
222 Non-fixed-station monitoring (conventional during key seasons and flows)
Monitoring Levels
Biological 0
Habitat 0
Physical Chemistry 2
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
Algal Grwth/Chlorophyll a Overall Use Support Moderate
  • Internal nutrient cycling (primarily lakes)
  • Moderate
Algal Grwth/Chlorophyll a Aquatic Life Support Moderate
  • Internal nutrient cycling (primarily lakes)
  • Moderate
Algal Grwth/Chlorophyll a Primary Contact Recreation Moderate
  • Internal nutrient cycling (primarily lakes)
  • Moderate
Siltation Overall Use Support Moderate
  • Agriculture
  • Natural Sources
  • Moderate
  • Slight
Siltation Aquatic Life Support Moderate
  • Agriculture
  • Natural Sources
  • Moderate
  • Slight
Nutrients Overall Use Support Slight
  • Agriculture
  • Internal nutrient cycling (primarily lakes)
  • Natural Sources
  • Moderate
  • Moderate
  • Slight
Nutrients Aquatic Life Support Slight
  • Agriculture
  • Internal nutrient cycling (primarily lakes)
  • Natural Sources
  • Moderate
  • Moderate
  • Slight
Nutrients Primary Contact Recreation Slight
  • Agriculture
  • Internal nutrient cycling (primarily lakes)
  • Natural Sources
  • Moderate
  • Moderate
  • Slight