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Dutch Hollow 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 Reservoir lake, this is considered Excellent.
Dutch Hollow Lake has been monitored by volunteers since 1998. 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. Additional monitoring has been done through projects funded in part by DNR Lake Grants. 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 |
|---|
| Dutch Hollow Lake - Black Forest Bay (Herbicide Monitoring) | 10048308 | Map | 2021 | Details |
| Dutch Hollow Lake - Deep Hole | 573060 | Map | 2024 | Details |
| Dutch Hollow Lake - Marina (Herbicide Monitoring) | 10048310 | Map | 2021 | Details |
| Dutch Hollow Lake - Summit Bay (Herbicide Monitoring) | 10048309 | Map | 2021 | Details |
| Dutch Hollow Lake - Woodland Bay (Herbicide Monitoring) | 10048307 | Map | 2021 | Details |