A march to protest the proposed raising of the Warragamba Dam wall will be held in Katoomba on Sunday, June 9.
Protest organiser Harry Burkitt, the Colong Foundation's Give a Dam campaigner, said he expected 700 people to attend the march which kicks off at 11.30am outside the Carrington Hotel.
The march will head down Katoomba, Waratah and Lurline streets before gathering at Kingsford Smith Park around 12.30pm. Speakers from the Blue Mountains Conservation Society, the Public Service Association, a traditional owner, Blue Mountains mayor Mark Greenhill and Mr Burkitt will address the crowd.
"We're calling for the federal Liberal government to step up and call out the NSW Liberal party for indiscriminately going after a plan that will destroy a World Heritage site," Mr Burkitt said. "We call on environment minister Sussan Ley to make the right decision and protect this Australian site."
It's proposed to raise the Warragamba Dam wall by 14 metres to reduce flood risk in the Hawkesbury-Nepean Valley. Environmentalists say parts of the Blue Mountains World Heritage Area will be inundated as a consequence. Hundreds of Indigenous sacred sites are also at risk of inundation.
The NSW government is developing an environmental impact statement for the dam plan, to be released this year.