Impaired Water - Trego Lake (Trego Lake)
Washburn County, Wisconsin
SC21
2712000
383.26
Water is impaired due to one or more pollutants and associated quality impacts.
Notes
Trego Lake was evaluated for phosphorus and algae every two-year cycle from 2014 and 2024. Chlorophyll-a values were too high as seen in algal blooms on the lake during the summer months. Chloride evaluation in the 2022 cycle showed good conditions.

This lake is covered by a restoration plan: Implementation Plan for the Lake St. Croix Nutrient Total Maximum Daily Load (expires in 2025).
Listing Details
Pollutant
Unknown Pollutant
Listed For
Recreation
Impairments
Excess Algal Growth
Current Use
Restricted Recreation
Listing Status
303d Listed
Attainable Use
Recreation
Priority
Low
Designated Use
Recreation
303(d) ID
2018-282
Listing Date
4/1/2018
Impaired Water Notes
This water was assessed during the 2018 listing cycle; new chlorophyll sample data exceeded 2018 WisCALM listing thresholds for the Recreation use. Total phosphorus data were clearly below Recreation use and Fish and Aquatic Life use listing thresholds.
Date
8/4/2017

Impaired Water Notes
This lake is covered by the following restoration plan and was classified as Category 5W as a result: Implementation Plan for the Lake St. Croix Nutrient Total Maximum Daily Load (2025).
Date
7/24/2019