CALPE council closed La Fossa beach to bathers on Wednesday morning after water tests taken on Tuesday.
A sample reviewed by the General Directorate of Water suggested the water was unsuitable for swimming due to pollution concerns.
Red flags were raised and new sampling has been taking place which means swimming cannot resume until Thursday at the earliest.
Calpe council said it was confident that the fresh tests will give the all-clear and any issues have been resolved.
Local water firm Aquas de Calpe carried out sampling on Monday which showed no problems.
La Fossa beach has been a ‘Blue Flag’ environmental award holder for 36 years.
Javea’s Arenal beach was closed for two days in late July after tests reported fecal matter in the water.
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