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My lake is green. Can I swim in it still?

This is the time of year when warm weather makes ideal conditions for the growth of blue-green algae (cyanobacteria). As of now, none of the lakes are experiencing full-lake algal blooms as defined by the State of Maine, which is when water clarity is less than 13 feet. But you may see some localized algae accumulation on your shoreline, depending on how the wind is blowing. If you live on North Pond, your lake is definitely green and trending toward full bloom conditions.

Currently, water clarity in North Pond is 7 feet at our regular deep hole monitoring site. 7 Lakes Alliance and the North Pond Association are closely monitoring the situation. Whether you are on North Pond or another lake, the conditions on the shoreline of any one camp can change from day to day and hour to hour, depending on the wind. If the water clarity drops below 3 feet at our regular monitoring site, we do not recommend swimming anywhere in the lake. You also should not swim in scums like the one pictured to the right (nor let your pets do so either!). The Maine Department of Environmental Protection suggests you shouldn't swim in water where you can't see your feet if the water is up to your chest.


Because things change so quickly, we can't come to everyone's camp and tell you if the water is safe. It is important to note there have been no documented cases of pet deaths due to algae in Maine, and we have not yet detected any significant algal toxin in any of the lakes (including in the middle of the North Pond bloom last year). There is always the potential for a bloom to be harmful, and some people are skin-sensitive to the algae, so everyone needs to be aware of the conditions.


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