If a private well is a properly installed drilled well, it is unlikely to be impacted by Harmful Algal Blooms present in the lake. If the well is a shallow well installed along the shore of a lake experiencing a harmful algal bloom, toxins associated with the bloom may be present in the well water. In-home treatments such as boiling, disinfecting water with chlorine or ultraviolet (UV), and water filtration units do not remove the toxins associated with harmful algal blooms.
There are treatment units on the market that have been shown to reduce microcystin levels in water, but it is not known if the microcystins would be reduced to a level considered safe. Since individual water supplies are not regulated or monitored, it is not known if there is a health risk to drinking the water from your private well.