Results from samples taken from Lake Rosalind and Marl Lake on November 24, 2016 by the Ministry of the Environment and Climate Change continue to show the presence of microcystins in both lakes.
However, because the results from both lakes indicate microcystin levels below the Maximum Allowable Drinking Water Concentration of 1.5 micrograms/litre, the Grey Bruce Health Unit has rescinded its advisory. The advisory originally recommended that water from the lakes not be used for bathing or as a source of potable water, and that fish from the lakes not be consumed.