Mariposa Lake IA 03-NSK-867

Jasper County S32T81NR18W 6 mi. NE of Newton.

This is a Legacy Assessment. Prior to 2004, assessments were developed under a methodology that pre-dated the Integrated Report guidelines.

Assessment Cycle

1998

Result Period

1994 - 1996

Designations

Assessment Type

Monitored

Integrated Report

Category 0

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

The assessment developed for the 1994 and 1996 reports (above) was reviewed and approved by the DNR Fisheries Bureau. Water quality problems related to siltation and nutrients from nonpoint sources remain for this lake. At the recommendation of the DNR Fisheries Bureau, this lake was placed on the 1998 list of Section 303(d) waters.

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