UPDATE Blue-Green Algae Bloom – Sept 4 & 5 2023

UPDATE Blue-Green Algae Bloom – Sept 4 & 5 2023

Blue-Green Algae Confirmed

Lab Tests – Toxin Levels Below Drinking Water and Recreational Limits

A blue-green algae bloom was reported on the north shore of Kennisis Lake near the second bridge at Kelly Lake.  The algal bloom was first noticed midday on September 4.  The visible bloom dispersed later in the day when the wind and lake wave action increased and then returned the next day (Sept 5) when the lake was calm. The visible bloom had dispersed by September 6 and has not returned.

A report was made to the MECP (Ontario Ministry of the Environment, Conservation and Parks) and MECP staff were able to visit the site on September 5, assess the algal bloom and take samples for laboratory analysis. 
The results of the lab analysis were provided to the KLCOA on September 11.  The results of the testing show that the bloom was indeed blue-green algae, but fortunately toxin levels were well below the Ontario Drinking Water Standard for Microcystin-LR of 1.5 ug/L and Health Canada’s recreational limit of 10 ug/L.

The MECP advises to err on the side of caution from a health and safety perspective, when a potential bloom is present.  Follow the guidelines as laid out  here and here . 
Here is an additional information sheet on Blue-green algae prepared by the MECP.  

Algal blooms more typically occur in the fall when unseasonably warm temperatures occur. The KLCOA is encouraging people to check their shorelines if they are at their properties and report any possible sightings as follows:

  1. Take pictures of the possible bloom and surrounding shoreline.  Note the date, time and weather conditions (wind intensity and direction, wave action).
  2. Report the possible bloom to the MECP:

Spills Action Centre at 1-866-663-8477


  1. Collect a sample of the algae in a clean large glass container and keep the sample refrigerated.
  2. Notify the KLCOA.  

The KLCOA is regularly in contact with the MECP and will continue to update you as new information becomes available.  The KLCOA has also reported this possible bloom to the Municipality of Dysart et al, the County of Haliburton and the Haliburton, Kawartha, Pine Ridge District Health Unit.

The KLCOA has been working with our community to control nutrient loading in our lakes by advocating for natural healthy shorelines, proper septic inspection and maintenance and eliminating the use of fertilizers near our lakes.  With this confirmed blue-green algae event, this focus will become even more critical.