Impaired Water - Upper Saint Croix Lake (Upper St. Croix Lake)
Douglas County, Wisconsin
SC18
2747300
828.28
Condition has remained stable; water is not impaired.
Notes
This water was assessed during the 2014 listing cycle; total phosphorus and chlorophyll-a data clearly met 2014 WisCALM Recreation and Fish and Aquatic Life thresholds.

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. This water was also assessed for chlorides and sample data were clearly below 2016 WisCALM chronic and acute listing criteria for the Fish and Aquatic Life use.

This water was assessed during the 2018 listing cycle; new total phosphorus and chlorophyll sample data were clearly below 2018 WisCALM listing thresholds for the Recreation use and the Fish and Aquatic Life use.

Assessments of new total phosphorus and chlorophyll data during the 2020 listing cycle confirm good condition of Aquatic Life and Recreation uses.
Listing Details
Pollutant
Mercury
Listed For
Impairments
Mercury Contaminated Fish Tissue
Current Use
Listing Status
Water Delisted
Attainable Use
Priority
Delisted 2010
Designated Use
303(d) ID
Listing Date
4/1/1998
Impaired Water Notes
Sites where data collected post 2000 -2007 and shows that general advice is sufficient. Bold shows sites that have been removed from the post-2000 site specific advisory list. Unbolded sites may be on the 303d list because they were on a pre-2000 advisory list but the locations fall under the general advisory.

Delist in 2010 Hg FCA based on Walleye 2004 data (10 samples). This waterbody has data after the methodology changed for fish consumption advice. This waterbody has enough fish tissue samples to remove these waters from the 303(d) list as a FCA, although they will still all be covered under the state's general advisory for fish consumption. The post-2000 data confirms that these sites do not need advice more stringent that the statewide general advice.
Date
10/1/2009