Impaired Water - Hemlock Lake (Hemlock Lake)
Chippewa County, Wisconsin
LC21
1853400
29.62
Water is impaired due to one or more pollutants and associated quality impacts.
Notes
Hemlock lake is on the 303(d) list due to mercury from atmospheric deposition and is proposed for removal based on 2001 updated Fish Consumption advisories.

Total phosphorus and chlorophyll were assessed for Hemlock Lake in 2012, 2014, and 2016. This lake was listed as impaired for phosphorus in 2012.
Listing Details
Pollutant
Total Phosphorus
Listed For
Recreation
Impairments
Impairment Unknown
Current Use
Restricted Recreation
Listing Status
303d Listed
Attainable Use
Recreation
Priority
Low
Designated Use
Recreation
303(d) ID
2012-2011
Listing Date
4/1/2012
Impaired Water Notes
This lake was assessed during the 2012 listing cycle, and total phosphorus sample data exceed criteria for the recreational use.
Date
3/1/2013

Impaired Water Notes
This water was assessed during the 2014 listing cycle; total phosphorus sample data exceed 2014 WisCALM listing thresholds for the Recreation use, however, chlorophyll data do not exceed REC thresholds. Total phosphorus and chlorophyll data do not exceed Fish and Aquatic Life thresholds.
Date
3/24/2014

Impaired Water Notes
This water was assessed during the 2016 listing cycle; total phosphorus sample data exceeded 2016 WisCALM listing thresholds for the Recreation, however, chlorophyll data do not exceed REC thresholds. Total phosphorus and chlorophyll data clearly met thresholds for Fish and Aquatic Life use.
Date
10/16/2015

 
Pollutant
Mercury
Listed For
Impairments
NA
Current Use
Listing Status
Pollutant Removed
Attainable Use
Priority
Delisted 2020
Designated Use
303(d) ID
183
Listing Date
4/1/1998
Impaired Water Notes
Hemlock lake is on the 303(d) list due to mercury from atmospheric deposition. This water was assessed during the 2012 listing cycle, and total phosphorus sample data exceed 2012 WisCALM listing thresholds for the recreation use; however, chlorophyll a data are insufficient.
Date
4/19/2012

Impaired Water Notes
This listing was part of a set removed from the impaired waters list due to a change in fish consumption advisory levels in 2001. In 2001 Wisconsin DNR put into effect a statewide fish consumption advisory for mercury due to atmospheric deposition. Most of the lakes removed from the specific fish consumption advisories list in 2001 were not removed from the impaired waters list even though the thresholds had changed. For the 2020 assessment process WDNR requested delisting of 91 waters with residual mercury listings from prior to 2001. This request was approved by US EPA.
Date
9/4/2018