Sue Jackson said the environmental vandalism was carried out on the rocks at the crossing to the Sheepskin property at Burragate, where she says, the owner is equally upset.

"The river is a beautiful swimming area and was utilised by many locals over this Christmas/New Year period - as it usually is," Ms Jackson said.

Barrie Jackson said that although it was accessed by a privately maintained road, the Jacksons and the owner of Sheepskin were happy for people to come and enjoy what the river had to offer.

"For the most part, visitors do not leave rubbish and respect the private road sign," he said.

Mr Jackson said he noticed the graffiti on Tuesday, January 4 and said that the police had been informed.

"It appears from the graffiti that there is one or more individuals trying to stop people gaining access to this beautiful part of the Towamba River. How they can justify this by such a gross act of vandalism beggars belief," Mr Jackson said.

"We would like to see the individuals involved held to account and required to return the river bed to its former natural beauty. The police have been notified of the vandalism by ourselves and the owner of Sheepskin and have logged our complaints," Mr Jackson said.