Test results for the week of June 12 indicate that all public beaches are posted as unsafe for swimming, said Durham Health yesterday.
In a separate advisory, the City of Oshawa announced that from Friday, June 16 to Thursday, June 22, Lakeview Park Beach is considered unsafe for swimming by the Durham Region Health Department.
Beaches are posted as unsafe for swimming when elevated levels of E. coli exceed the provincial standard of 200 E. coli per 100 ml of water.
The Health Department reminded the public not to swim in beach water for at least 48 hours after heavy rainfall, as bacteria levels can increase due to run-off.
Throughout the summer, the Health Department conducts bacteriological water tests to determine if beaches are safe for swimming. The Public Health Ontario Laboratory in Peterborough tests the water samples. Results are shared with the media by the Friday of each week, to assist with public notification of beach postings.