Impaired Water - Big Lake (Big Lake)
Polk County, Wisconsin
SC04
2615900
244.72
Proposed for removal from impaired waters during assessment period.
Notes
Big Lake was evaluated for phosphorus and algae every two years between 2014 and 2020. Chlorophyll-a values were too high as seen in algal blooms on the lake during the summer months. In the 2022 cycle algal levels were below criteria, prompting delisting.

This lake is covered by a restoration plan: Implementation Plan for the Lake St. Croix Nutrient Total Maximum Daily Load (2025).

Listing Details
Pollutant
Unknown Pollutant
Listed For
Impairments
NA
Current Use
Listing Status
Delist
Attainable Use
Priority
Not Applicable
Designated Use
303(d) ID
2014-291
Listing Date
4/1/2014
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
7/12/2017

Impaired Water Notes
This water was assessed during the 2014 listing cycle; chlorophyll sample data exceed 2014 WisCALM listing thresholds for the Recreation use, however, total phosphorus data do not exceed REC thresholds. Total phosphorus and chlorophyll data do not exceed Fish and Aquatic Life thresholds.
Date
1/15/2014

Impaired Water Notes
This water was assessed during the 2016 listing cycle; total phosphorus sample data were clearly below 2016 WisCALM listing thresholds for Recreation use and Fish and Aquatic Life use. Chlorophyll sample data were clearly below FAL use listing thresholds and did not exceed REC listing thresholds. The Excess Algal Growth listing remains because chlorophyll data were not clearly below REC listing thresholds.
Date
10/26/2015

Impaired Water Notes
This water was assessed during the 2020 listing cycle; new chlorophyll sample data were clearly below 2020 WisCALM listing thresholds for the Aquatic Life use. Implementation Plan for the Lake St. Croix Nutrient Total Maximum Daily Load (2025).
Date
7/24/2019

Impaired Water Notes
This water was assessed during the 2022 cycle; new chlorophyll-a data were clearly below 2022 WisCALM listing criteria for Recreation use.
Date
6/14/2021