Swimmers at Primrose Sands Beach have been told to stay out of the water after recent tests revealed high levels of bacteria on two separate occasions.
The Sorell Council imposed a precautionary swimming ban on Thursday following poor results from the latest round of testing.
Warning signs have been placed at all beach entrances, advising against swimming for public safety.
The council said the signs will be removed once water quality is confirmed to have returned to safe levels.
Additional water samples are being collected today in the hope that conditions have improved since the first poor results were reported on Monday.
The latest closure comes after the Clarence City Council closed parts of Bellerive Beach late last week due to elevated levels of bacteria.
According to the council, the contamination at Bellerive Beach was likely caused by wet weather and stormwater runoff affecting the River Derwent.
Sampling this week has shown improved water quality at Bellerive Beach, opening it up to swimmers once again.
