Wollongong City councillors fear bulldozers will roll in and demolish an important piece of NSW history before assessing the Waterfall site's heritage significance.
The NSW Department of Health has earmarked many of the buildings at the former Garrawarra Hospital for demolition.
The purpose-built hospital cared for and quarantined people with tuberculosis from the early 1900s to the 1950s. The run-down site is situated near the current residential aged care Garrawarra Centre.
The health department claims buildings are set to be demolished out of work health and safety concerns due to the age of the structures and the hazardous materials used in the construction.
Cr Leigh Colacino and the council are calling on the state government to provide funding to the state heritage office to facilitate an assessment of the heritage significance of the entire Waterfall site prior to any demolition.
The buildings marked for demolition include the female and male wards, a chalet, the water tower, furnace and some residential houses.
"The site should be state heritage listed," Cr Colacino said. "It was a state-of-the-art facility put out in Waterfall because it was so far away from Sydney. Building it was not a slap-dash approach. The establishment was considered the best facility to help people get better.
"The facility was self-sufficient with their own markets, orchards and water supply.
"The site has been left to go to wrack and ruin. How can we say that 100 years after the facility was built that we don't care about its historical merit and value?"
Cr Colacino recognised not all buildings needed to be retained but said the majority of them did for their historical link.
The NSW Health department has not set a start date for demolition.
At Monday night's meeting, councillors gave council staff the power to apply for a interlocutory injunction through the court if demolition begins before a heritage assessment is undertaken.
He wants residents across the state to be consulted before demolition is approved.
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Last year the council released a report concluding the site should be listed on the state heritage list and the NSW Health department also had a peer-reviewed report that assigned buildings with an "exceptional, high, moderate and low value".
Cr Colacino said several of the buildings to be demolished were deemed "exceptional".
He said the health department had previously indicated the expense to perverse and remediate the site was too high.
Brief history of the hospital
The site was known as the Hospital for Consumptives from 1909-1913 because it became the Waterfall State Sanatorium.
According to the South East Services Local Health District, as at 1914 the Waterfall State Sanatorium was the principal hospital in the state for the treatment of consumptives and contained 370 beds.
In 1919 Waterfall was now the largest sanatorium in NSW and accommodated 788 patients.
More than 2000 people died, including doctors and nurses, and were buried in the nearby cemetery.
With the rise of penicillin use, after extensive remodelling Garrawarra Hospital was re-opened in 1958 as a hospital for people with chronic diseases and diseases of the ageing.
From 2000, it has been Garrawarra Centre for Aged Care, which is a multi-purpose aged care centre specialising in dementia care services.