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Green Lake
Water Quality
One measure of a lakes health is the trophic state, which relates to the amount of algae in the water. The average summer trophic state for the last 5 years was 43 (Mesotrophic) and was determined using chlorophyll data. For a Deep Seepage lake, this is considered Good. Deep Seepage lakes stratify, or form separate layers of water, during the summer months and have no inlet or outlet.
Green Lake has been monitored by volunteers since 1986. Volunteers monitor water clarity with a black and white Secchi disk. Some also collect water samples, which are sent to the State Lab of Hygiene to be analyzed. Volunteers are the source of the majority of Wisconsin's lake water quality data, and their dedication is greatly appreciated. Reports and graphs featuring data collected by volunteers, DNR staff and others can be viewed below.
Water Quality Reports and Graphs
| Station Name | Station ID | Map | Max Year | Reports |
|---|
| Green Lake - Deep Hole | 673208 | Map | 2024 | Details |
| Green Lake - Green Lake | 674003 | Map | 1979 | Details |
| Green Lake - [Herbicide Sampling Site GL1] | 10051486 | Map | 2019 | Details |
| Green Lake - [Herbicide Sampling Site GL2] | 10051487 | Map | 2019 | Details |
| Green Lake - [Herbicide Sampling Site GL3] | 10051488 | Map | 2019 | Details |
| Green Lake - [Herbicide Sampling Site GL4] | 10052079 | Map | 2019 | Details |