Five beaches in Windsor-Essex have been posted as unsafe for swimming.
The Windsor Essex County Health Unit reports high levels of bacteria in the water at Colchester, Mettawas, Point Pelee North West, Sandpoint and Seacliff beaches.
The beaches are open, but swimming is not recommended.
Holiday Beach also remains closed due to erosion from high lake levels.
All other beaches in Windsor-Essex are listed as safe for swimming.
The water testing was done on Tuesday.