Ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs
This content is intended for the public covered by the exceptions of the Charter of the French language and its regulations. If you read on, you confirm that you fall within one of these exceptions.

Blue-green algae

Blue-green algae, or “cyanobacteria” by their scientific name, are microorganisms that have existed for over three billion years. They are naturally present in the lakes and rivers of Québec at low concentrations. Normally they do not cause any problems. However, under certain conditions blue-green algae can reproduce quickly and become extremely abundant. They then form what are called “algal blooms”.

Best practices




Intervention plan


Regulations concerned by the Plan


Governmental partners in the Intervention Plan


Managing algae bloom episodes


Other useful links


For more information about blue-green algae, call:

418-644-4545 (Québec area)
514-644-4545 (Montréal area)
1-877-644-4545 (elsewhere in Québec)
Regional Offices


Evaluation of the page Learn more

As part of its 2019—2023 Strategic Plan, the Ministère wishes to improve access to information that is available on its website. Can we count on your co-operation by responding to a survey at the bottom of each page? This will enable us to evaluate how easy it was to find the information you were looking for.

How easy was it to find the information you were looking for today?
Easy Difficult

Return to the top