Only one local beach is posted as unsafe for swimming this week.
The Windsor-Essex County Health Unit said swimming is not recommended at Colchester Beach in Essex because bacteria levels are too high. Colchester Beach has an E. coli count of 897.
It's the fifth time this year that Colchester Beach has tested high for bacteria and a harmful algae bloom in western Lake Erie has also reached that area.
No beaches are closed this week and swimming is still not allowed at Holiday Beach in Amherstburg because erosion from high water levels on Lake Erie have made it unsafe.
Warnings are posted when the water samples have E. coli levels that are greater than 200 per 100 millilitres of water and are shut down when the E. coli count is 1,000 per 100 millilitres of water or higher.
People can get sick from water with high levels of E. coli. The most common illnesses are stomach and intestinal illnesses such as vomiting and diarrhea, along with lung, eye, ear, nose, or throat infections or skin issues. Swallowing contaminated water is the main way people may get sick.
Health officials have started conducting beach water quality monitoring at all nine public beaches at least once a week. The testing runs from June to September to make sure the E. coli counts in the water are below provincial standards. Beach sampling will take place every Monday and if the beach is closed due to high E. coli levels, it will be resampled on Thursday of the same week. Beach water quality results are released every Wednesday during the summer.
The health unit does not recommend swimming after a heavy rainfall even if the beach is open for swimming.