Water Quality Update

Visual observations of Three Mile Lake on July 31st by the Simcoe Muskoka District Health Unit confirmed the likelihood of a blue-green algal bloom. The MECP collected a water sample from the Deebank Village area (west end of the lake) on August 1, 2018 and confirmed it.

Note that since 2011, the MECP lab results have regularly exceeded the safe drinking level, but they have NOT exceeded the safe recreational water (swimming) level. Swimming and other water sport activities should be avoided in areas where the blue-green algae bloom is visible.

The MECP lab results for microcystins levels are below. The safe drinking maximum is 1.5 µg/L. Past history shows that sample results from separate locations can be very different.
Our own weekly testing at two locations over the entire summer show microcystins levels below 0.2 µg/L.

August 1st – 1.5 µg/L
August 14th – 0.56 µg/L