A Hamilton Conservation area is restricting swimming following the discovery of possible blue-green algae.
The beach and swimming area at Christie Lake Conservation Area in Dundas is now closed to swimmers and animals as testing continues.
People who come into contact with visible blue-green algae or ingest water containing blue-green algae may experience skin irritation, rash, sore throat, sore red eyes, swollen lips, fever, nausea and vomiting and/or diarrhea.
Blue-green algae forms in shallow, warm, slow-moving or still waters.
Temperature fluctuations, high nutrient loads, water mixing, slow-moving or still waters, provide the ideal environment for the proliferation of naturally occurring blue-green algae.
Algae/vegetation in the water can give off an offensive odour as it dies and decays.
Testing has been carried out by the Ministry of Environment, Conservation and Parks.