Impaired Water - Long Lake (Long Lake (Big Long))
Manitowoc County, Wisconsin
MA04
77500
127.28
Water is impaired due to one or more pollutants and associated quality impacts.
Notes
Long Lake was listed in 2010 due to high phosphorus concentrations and eutrophication impairment of the Aquatic Life use.

was evaluated for phosphorus and algae every two years between 2014 and 2020. Phosphorus levels were found to be too high, which was reflected in algal blooms. This lake is covered by a watershed plan: CalMan Lakes Watershed Plan (2028).
Listing Details
Pollutant
Total Phosphorus
Listed For
Recreation
Impairments
Eutrophication, Degraded Biological Community, Excess Algal Growth
Current Use
Restricted Recreation
Listing Status
TMDL Development
Attainable Use
Full Body Contact - Swimming, Boating
Priority
High
Designated Use
Full Body Contact - Swimming, Boating
303(d) ID
2010-7
Listing Date
4/1/2010
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
Long Lake is a deep seepage lake with a long history of poor water quality. Data dating back to 1992 to present show high total phosphorus concentrations and low secchi values, and significant algae blooms during the summer. Its average Total phosphorus concentration (Deep Hole Station 363230 in 2005, 2006, 2008,) is .068 mg/l, which is three times above the impairment threshold of .02 for deep seepage lakes. There have been high TP readings from 1992 to present each summer. Average TSI based on 7 Chlorophyll samples collected between 7/15/2005 and 9/15/2008 was 64, which exceeds the impairment threshold of 63 for deep lakes. It exhibits poor water clarity with a summer average secchi depth of 2.9 feet (2004 to 2008 data); its average TSI based on Secchi is 63, which also places it in the 'Poor' category for Deep Seepage lakes. The lake receives a considerable amount of agriculture runoff which highly impacts the lake water quality, habit, and fisheries. Several lake planning grants have been given to the Long Lake Advancement Association to assess the lake's condition. These studies have pointed to the fact that Long Lake's most significant problem is external phosphorus loading.
Date
10/16/2009

Impaired Water Notes
Degraded biological community impairement is proposed to be added in 2014 list based on aquatic macrophyte community assessment.
Date
6/7/2013

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, exceeded Fish and Aquatic Life use, and chlorophyll data exceeded REC and FAL thresholds.
Date
10/9/2015

Impaired Water Notes
This water was assessed during the 2020 listing cycle; total phosphorus sample data overwhelmingly exceeded 2020 WisCALM listing thresholds for the Recreation use and Fish and Aquatic Life use, and chlorophyll data also exceeded REC and FAL thresholds. Based on the most updated information, no change in existing impaired waters listing is needed.
Date
6/19/2019

Impaired Water Notes
This lake is covered by the following watershed plan and was classified as Category 5W as a result: CalMan Lakes Watershed Plan (2028).
Date
8/14/2019