Waukesha County, Wisconsin
FX04
762700
469.76
Water is impaired due to one or more pollutants and associated quality impacts.
Notes
Little Muskego Lake was listed from 1998 - 2018 for low dissolved oxygen impairment due to total phosphorus levels in the lake. This lake was assessed in the 2018 and 2024 cycles; phosphorus, algae, and dissolved oxygen data indicated healthy conditions. In 2026 the aquatic plant community was found to be impaired due to unspecified pollutants and this water was placed on the Impaired Waters List. Pollutant
Unknown Pollutant
Listed For
Fish and Aquatic Life
Impairments
Degraded Aquatic Vegetation
Current Use
Unsupported Aquatic Life
Listing Status
Proposed for List
Attainable Use
Default - Fish and Aquatic Life
Priority
Low
Designated Use
Default - Fish and Aquatic Life
303(d) ID
2026-48
Listing Date
4/1/2026
Pollutant
Total Phosphorus
Listed For
Fish and Aquatic Life
Impairments
NA
Current Use
Unsupported Aquatic Life
Listing Status
Water Delisted
Attainable Use
Default - Fish and Aquatic Life
Priority
Delisted 2018
Designated Use
Default - Fish and Aquatic Life
303(d) ID
241
Listing Date
4/1/1998
Impaired Water Notes
This water was assessed during the 2018 listing cycle; new total phosphorus, chlorophyll, and dissolved oxygen sample data were clearly below 2018 WisCALM listing thresholds for the Recreation use and the Fish and Aquatic Life use. The total phosphorus/DO listing is proposed for delisting in 2018.
Date
7/14/2017