Concern: Ann Lake in west central Kanabec County, has impaired waters due to high phosphorus levels.

The majority of the high phosphorus is due to internal loading or high phosphorus levels in the bottom lake sediment.

Study Results: This study looked at four treatment options to address the high internal phosphorus levels.

For each treatment option, the study lists the treatment areas, chemical dosing rates, costs, phosphorus removal efficiency and potential impacts to wild rice and other environmental factors.

Four Treatment Options Studied:

• Aluminum Sulfate
• Phoslock (trademarked)
• Polyaluminum Chloride
• Hypolimnetic Aeration

We hope this study will create further discussion for other similar lakes with high internal nutrient loading. Looking for input from concerned lakeshore owners.  Also looking to agency staff for an open discussion of these options for environmental concerns and funding options.