Save Cliefden Caves Association secretary Harrison Burkitt said the caves met the criteria for listing because they were important to the state’s natural and cultural history, they were the first limestone deposits discovered in NSW and the 450 million-year‐old invertebrate fossils at Fossil Hill were found nowhere else in the world.

Mr Burkitt also said the site was rare because the thermal spring was one of only three in the state and its blue stalactites were in only one other location.

“We regret that it took such a threat [as the Cranky Rock dam proposal] to begin the listing process, but we hope that good will come out of it through this,” he said.

“Cliefden needs and deserves protection, with or without the looming threat of flooding.”

Inland Rivers Network Bev Smiles said in her submission there was a need for ongoing research into the hydrology of the karst system.

“The connectivity in the landscape with groundwater and surface water sources is essential knowledge to inform policy and decision-making in regard to improved management of water use into the future,” she said.

“The protection through listing on the State Heritage Register will enable this research to be undertaken and thus improve our understanding of the movement of water through the landscape and through timescales.” 

The Heritage Council of NSW signalled its intention to consider the site in February and will assess the submissions before making a recommendation to the minister.