Donegal County Council is warning the public not to swim at Lady's Bay in Buncrana this weekend due to high levels of bacteria.
According to a safety notice from the local authority, there are currently elevated levels of E.coli in the water.
The issue is said to the result of a combination of heavy rainfall and agricultural activities.
Bathers are being advised that this is temporary measure with the Council monitoring the situation closely.
Local Cllr Jack Murray is urging the public to heed the warning: