Impaired Water - Cedar Lake (Cedar Lake)
Polk, St. Croix County, Wisconsin
SC04
2615100
1,120.36
Water is impaired due to one or more pollutants and associated quality impacts.
Notes
Cedar Lake has been listed on the state's 303(d) impaired waters list since the 1998 cycle for Total Phosphorus. The TMDL for phosphorus was approved in 2003.

This lake was assessed for phosphorus and algae every two-year cycle from 2012 to 2024; there was consistently elevated phosphorus and algae.
Listing Details
Pollutant
Total Phosphorus
Listed For
Recreation
Impairments
Excess Algal Growth, Elevated pH
Current Use
Restricted Recreation
Listing Status
TMDL Approved
Attainable Use
Recreation
Priority
Not Applicable
Designated Use
Recreation
303(d) ID
70
Listing Date
4/1/1998
Impaired Water Notes
This water was assessed during the 2018 listing cycle; new total phosphorus and chlorophyll sample data exceeded 2018 WisCALM listing thresholds for the Recreation use and Fish and Aquatic Life use.
Date
7/10/2017

Impaired Water Notes
This TMDL report is for Cedar Lake, located in Alden Township in Polk county and Star Prairie Township in St. Croix county Wisconsin, respectively. The lake is located within the St. Croix River drainage basin and geographically spans Sections 34 and 35, T32N, R 18W - Polk county and Sections 2 and 3, T31-32 N R18W in St. Croix county on the New Richmond North USGS quadrangle. Cedar Lake is listed on the Wisconsin Department of Natural Resources’ (WDNR) 1998 303(d) List of Impaired Waters. The Lake is nutrient (phosphorus (P)) impaired as a result of agriculture, internal loading and local land use, is listed as a medium priority water with external load sources are nonpoint source (NPS) dominating. The designated use for Cedar Lake is defined as a full recreation, warm water sport fishery water.

Water quality in Cedar Lake is generally poor to very poor, falling into the eutrophic to hypereutrophic category (see Cedar Lake - Management Plan, Polk and St. Croix Counties, page 3) dated 1989 (Attachment 2). Summer (1986-2001) surface water column total phosphorus levels average 83 ug/l. Summer algal blooms result in foul odors and an unsightly build-up of algae biomass on the shoreline. In addition, trophic conditions in the lake limit rooting depth for emergent vegetation used by the resident fish populations. As a result, these impairments impact the recreational/aesthetic value of the lake and stress sport fish populations.
Date
7/3/2003

Impaired Water Notes
Water quality in Cedar Lake is generally poor to very poor, falling into the eutrophic to hypereutrophic category (see Cedar Lake - Management Plan, Polk and St. Croix Counties, page 3) dated 1989 (Attachment 2). Summer (1986-2001) surface water column total phosphorus levels average 83 ug/l. Summer algal blooms result in foul odors and an unsightly build-up of algae biomass on the shoreline. In addition, trophic conditions in the lake limit rooting depth for emergent vegetation used by the resident fish populations. As a result, these impairments impact the recreational/aesthetic value of the lake and stress sport fish populations.

Water quality standards Cedar Lake is not currently meeting applicable narrative water quality criterion as defined in NR 102.04 (1); Wis. Admin. Code: “To preserve and enhance the quality of waters, standards are established to govern water management decisions. Practices attributable to municipal, industrial, commercial, domestic, agricultural, land development or other activities shall be controlled so that all waters including the mixing zone and the effluent channel meet the following conditions at all times and under all flow conditions: (a) Substances that will cause objectionable deposits on the shore or in Cedar Lake TMDL the bed of a body of water, shall not be present in such amounts as to interfere with public rights in waters of the state, (b) Floating or submerged debris, oil, scum or other material shall not be present in such amounts as to interfere with public rights in waters of the states, (c) Materials producing color, odor, taste or unsightliness shall not be present in such amounts as to interfere with public rights in waters of the state.” The application of a narrative criterion for Cedar Lake necessitates the development of a site-specific in-water value for the purpose of this TMDL.

The site-specific eplimnetic total phosphorus concentration goal has been identified as 50 ug/L. The in-lake TP concentration represents the mean growing season (GSM) eplimnetic concentration. This narrative criterion is based on a comparison with similar lake types in the area taking into account site-specific conditions, using available monitoring data and modeling tools. The receiving water capacity in this situation represents cleaning-up the waterbody to achieve attainable uses.1 Based on a 2001 growing season (June/September) mean total phosphorus concentration of 100 ug/l, Cedar Lake is hypereutrophic. Specifically, the intent is to minimize the frequency of algal blooms and reduce nuisance conditions in the lake. The chlorophyll-a concentration in Cedar Lake responds directly to the in-lake phosphorus concentration. Cedar Lake is phosphorus limited based on a TN/TP ratio of 25. Lakes with ratios above 10 are considered to be phosphorus limited. As P concentration rises, the chlorophyll-a concentration rises and algal biomass production increases. This cause and effect relationship is measured using a Secchi disk to measure water clarity (poor water clarity results in limited emergent vegetation rooting depth and indicates the presence of significant biomass in the water column). Reducing P reduces chlorophyll-a, which results in improved water clarity and diminished algae production.
Date
4/7/2003

Impaired Water Notes
This water was assessed during the 2012 listing cycle, and total phosphorus and chlorophyll sample data exceed 2012 WisCALM listing criteria for the fish and aquatic life and recreation uses. Based on the 2012 assessment, a recreation use impairment (excess algal growth) caused by total phosphorus was added to this listing.
Date
6/15/2011

Impaired Water Notes
The phosphorus TMDL for Cedar Lake was approved by the USEPA August 19, 2003.
Date
8/19/2003

Impaired Water Notes
This water was assessed during the 2014 listing cycle; total phosphorus sample data overwhelmingly exceed 2014 WisCALM listing thresholds for the Recreation use and exceeded Fish and Aquatic Life use, however, chlorophyll data only exceeds REC thresholds.
Date
2/28/2014

Impaired Water Notes
This water was assessed during the 2016 listing cycle; total phosphorus sample data overwhelmingly exceed 2016 WisCALM listing thresholds for the Recreation use, and chlorophyll data exceed REC thresholds. Total phosphorus and chlorophyll data do not exceed Fish and Aquatic Life thresholds.
Date
10/12/2015

Impaired Water Notes
This water was assessed during the 2020 listing cycle; new total phosphorus sample data exceeded 2020 WisCALM listing thresholds for the Recreation use and Fish and Aquatic Life use; chlorophyll data only exceeded REC thresholds, not FAL.
Date
6/19/2019

Impaired Water Notes
This water was assessed during the 2022 listing cycle; new total phosphorus sample data may exceed 2022 WisCALM listing thresholds for the Recreation use and Fish and Aquatic Life use; chlorophyll data only exceeded REC thresholds, not FAL.
Date
5/30/2021