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Updated: June 15, 2018

Lake of Two Rivers Beach Now Open

Public beaches on Lake of Two Rivers are now open for 2018. Lab results obtained this spring have determined that toxins were not detected and naturally-occurring blue-green algae have returned to normal levels in Lake of Two Rivers.

Originally Posted: September 21, 2017 Updated: May 25, 2018

Lake of Two Rivers Beach Closure - Public Health Risk – Presence of Algae

Public beaches on Lake of Two Rivers are closed for swimming until further notice. Lab results from 2017 did confirm the presence of blue-green algae on Lake of Two Rivers. This type of algae can pose a health risk to pets and humans. Ontario Parks is continuing to monitor conditions for 2018, including further testing. Advisories issued in 2017 for Lake of Two Rivers will remain active until lab results can confirm water quality has improved.

When recreating on or near Lake of Two Rivers and the presence of algae is observed, please take the following precautions:

  • People or pets should not drink lake water (even if treated or boiled);
  • Do not use the water for food preparation or bathing;
  • Minimize direct contact with the water surface; and
  • If consuming fish, avoid eating the skin, organs, and fatty tissues.

What are blue-green algae?

Blue-green algae are microscopic organisms (cyanobacteria) that are naturally present in lakes and streams. They are usually present in low numbers but can, under the right conditions, rapidly increase and form blooms that discolour the water or produce floating rafts or scum.

Why can’t I drink the water if it is filtered or treated?

Boiling the water may rupture the cells and release more toxins. Toxins that may be released by blue-green algae are not removed by small scale treatment methods such as filtration, chlorination or ultraviolet light disinfection.

What are the potential health effects from drinking or coming in contact with water containing blue-green algae?

Some blue-green algae produce toxins that can pose a health risk to people and animals. Toxins are released into the water when the algae cells are damaged or begin to decay. Direct contact with the toxin can cause skin irritation and if ingested in higher concentrations may result in vomiting, nausea, diarrhea and abdominal pain.

Is it safe to eat fish caught from waters affected by a blue-green algae bloom?

Eating fish caught from affected waters is an unknown health risk. It is known that some algae toxins have been found to accumulate in fish tissues (for a short period of time), and particularly in organs such as the liver and kidneys. Toxin accumulation studies suggest that the muscle (fillet) tissue is less affected by algae toxins.

Please consult your local Health Unit for more information on blue-green algae and any potential health effects.

Please check back for updates.

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