The cruise ship Quest For Adventure is at anchor in the Foyle Estuary at Carnagarve – between Moville and Greencastle today.
Hundreds of passengers are visiting various parts of Co Donegal and Derry.
But local environment campaigners say the ship is just 50 metres from a beach where Donegal County Council has set a proposed sewage discharge point of the proposed Moville Greencastle Waste Water Treatment Plant.
Spokesperson Enda Craig said "It is difficult to comprehend that should this plant go ahead these visitors to our shores will be met in the first instance by the unholy sight and smell of this offensive discharge in the immediate vicinity of their ship.
This proposal and its location is hardly a suitable welcome and surely flies in the face of all attempts by local people attempting to attract additional footfall to this beautiful part of the Inishowen Peninsula. First impressions are all important.
It is surely high time our elected representatives made a determined stand and called for protection for this areas most valuable and beautiful asset."