Motorhomes could be banned from parking on a beach overnight amid claims toilets have been emptied on the sand.
Gwynedd council is also considering increased beach access charges at Morfa Bychan, known locally as Black Rock Sands, in Porthmadog.
Councillor Selwyn Griffiths claimed campers staying overnight had left a "disgusting" mess.
The council confirmed it is planning to bring in "additional measures".
Emma Walters, a warden at the Black Rock Sands Touring and Camping Park, claimed she had caught a camper emptying a toilet at the weekend.
She said: "When I told him it was disgusting, he said 'tough'. You have to be careful.
"People are very annoyed. It's not only a tourist area, it's a nature area."
The council said its beach staff told drivers they should not park overnight, but owners of motorhomes and campervans were "failing to comply with the requirements" so it would look at amending a by-law in order to take enforcement action.
A spokesman added: "The council will be taking action... additional measures being considered include significantly increasing beach access charges for motorhomes and campervans and amending the beach by-laws to include the prohibition of remaining on the beach in a motor vehicle overnight."
Mr Griffiths said up to 70 vehicles have been staying at the site overnight, leaving residents "very upset".
"People walk along the sand dunes and are disgusted by what they see there," he added.
Public toilets at the beach have also been used to empty toilet contents, according to Mr Griffiths - leaving them "clogged up... disgusting, overflowing."