Lugarno resident Megan Argent has launched a petition calling on the NSW government to purchase the historic 'Glenlee' property.
The homestead and surrounding bushland, which is located on the banks of the Georges River, could soon be subdivided into 31 residential lots, pending approval from the Georges River Local Planning Panel.
The development application lodged on May 6 also includes demolition works, construction of new roads, drainage and tree removal.
Mrs Argent believes the property should be retained as public land for future generations.
She said Glenlee, also known as Lugarno Farm, is listed on the National Trust Register as a part of the Lugarno Early Settlers Local Heritage Precinct.
"It is an irreplaceable part of St George district history," Mrs Argent said.
"It has been beautifully preserved by the same family as a working farm since 1908 and contains culturally significant evidence of Aboriginal occupation.
"There is no other site left like it in our LGA and it is a snapshot in time of our agricultural past, preserved since the area was first settled."
Mrs Argent said residents were concerned that a proposed 31-lot subdivision, bisected by two roads would 'obliterate' the entire historical and natural heritage of the site including rare Aboriginal rock carvings.
She said residents were also concerned about additional traffic congestion on the peninsula.
"They believe that development of such a scale will be disastrous for the ecologically sensitive Lime Kiln Bay, where endangered Eastern Curlew feed on the sand flats," Mrs Argent said.
"One hectare of the property is covered by blackbutt eucalypt bushland classed as 'High Ecological Value' which filters stormwater runoff from surrounding streets, and is habitat for swamp wallabies, echidnas and 12 species of threatened wildlife, including eastern ospreys, powerful owls, white-bellied sea eagles andendangered microbats."
Mrs Argent maintains that Glenlee is the only foreshore land in Lugarno where locals would be able to access and picnic on the river.
She said it enhances the iconic view enjoyed by thousands of visitors looking westwards from Oatley Park.
Georges River Environmental Alliance secretary Dr Sharyn Cullis said the organisation also held concerns about impact of stormwater on the Georges River if the 80 Boronia Parade development is to be approved.
"The design of the stormwater system for this gross over-development of Glenlee is deeply disturbing," she said.
"It involves the hardscaping of what has been two hectares of softly vegetated land that has absorbed and filtered run-off from the surrounding streets.
"The proposed underground pipe and drain system, will channel and dump the entire stormwater load of those established streets and this additional estate through one huge outlet pipe onto what is now a steep and pretty little creek-line, that is approximately 50 metres from its confluence with Lime Kiln Bay, on the Georges River. The little creek will be smashed by filthy flows."
Dr Cullis said a foreshore park would be a better use of the site.
"This is a unique opportunity for every level of government to be involved in sourcing the funds to buy the site, and achieve it," she said.
"If commercial development occurs, there are more socially and environmentally sensitive options.
Why not seek a mixture of public access to the foreshore, with the re-purposing of the old boatsheds and farm workshops.
"Here is where there could be a café or gallery for community functions, blended into the natural landscape, and with some urban lots."
Lugarno Progress Association president Michael Spring said Glenlee was an irreplaceable part of St George district history.
"The property has been on the market for some time and federal, state and local governments have had ample opportunity to recognise the value of this property to the community and the environment," he said.
"They have failed to act on any acquisition at fair market value and the property is now the subject of a development application which proposes subdividing the property into 31 separate lots with the possibility of multiple dwellings on some lots."
Georges River councillor Sam Elmir is expected to raise a question with notice about the proposed development at Monday's council meeting.
In the officer's response to Cr Elmir's questions the council officer stated that the land could only be compulsorily acquired by council "if an adopted strategic study showed that Peakhurst Ward had a shortage of open space".
However, it also noted "the Peakhurst Ward has the highest amount of open space per dwelling in the local government area".
"The site is not currently available for sale," the report stated.
"A compulsory acquisition of the site would need to occur in accordance with the provisions of the Land Acquisition (Just Terms Compensation) Act 1991.
"Council would need to resolve to prepare a planning proposal (Draft LEP) for the site and rezone it to RE1 Public Recreation (open space) and list the site on the land acquisition map.
"It is expected that based on its current residential zoning and the statutory requirement to take into account the site's development potential, the estimated cost of acquisition (including land value, legal costs, displacement costs, interests in the land) could exceed $15 million.
"Council would need to engage a qualified valuer to obtain a valuation to confirm this estimate."
To sign the petition, visit: parliament.nsw.gov.au.