The beach, adjacent to the Shore Greens on the town’s waterfront, is a popular spot with locals and day-trippers alike.
The Environmental Protection Agency, which issued the temporary ban on bathing from 11-13 June, says water quality at Lady’s Bay has been affected due to “suspected contamination from extreme weather/flooding”.
There have been recent reports of pollution on the Mill River in Buncrana.
Lady’s Bay had ‘good’ water quality standards for the 2012 and 2013 bathing seasons.
In 2012 the beach achieved a ‘Green Flag’ award, but it lost it for 2013 and did not regain it this year.