Some of the Illawarra and South Coast's most vulnerable areas may be left without a fire station, if a NSW Government push to temporarily close stations in the event of staffing shortages goes ahead.
"Catastrophic" fires could result, Leighton Drury of the Fire Brigade Employees Union says.
Helensburgh, Scarborough and Nowra Fire and Rescue are three of the stations which would be affected by the proposed changes.
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Mr Drury said "there's absolutely the potential" for a repeat of the Black Summer bushfires, which killed 25 people, if the proposed cuts go ahead.
"The longer you leave a fire burning the bigger it gets and the harder it becomes to control," he said.
"If resources are further away the problem gets exponentially worse."
We used to have a guaranteed response time of eight minutes - now we don't guarantee a response time at all- Leighton Drury, Fire Brigade Employees Union
Fire and Rescue NSW denies there are any plany to cut services.
"We are not closing fire stations," a spokesperson said.
"Trucks will only be temporarily taken offline if it is safe to do so and there are other trucks in the network which could quickly respond to an incident."
When asked how long trucks might be taken offline for, Fire and Rescue NSW did not respond. The union says there has been no upper limit placed on how long stations might be closed for in the event of insufficient local retained firefighters being available.
"If a fire station is not available it takes longer for resources to come from elsewhere," Mr Drury said.
"Minutes count in a fire. We used to have a guaranteed response time of eight minutes - now we don't guarantee a response time at all."
Mr Drury rejected suggestions that RFS volunteers could breach the gap.
"The RFS is made up of volunteers, there's no guarantee of service," he said.
"We don't just respond to fires, it's motor vehicle accidents, chemical spills, flooding. Beaing late to any of these can mean lives lost. We're the largest accredited rescue organisation in NSW - our capability goes beyond what the RFS is able to provide."
The union says the proposed changes are part of an ongoing cost-cutting exercise by the NSW Government.
"The shortage happens for a number of reasons," Mr Drury said.
"Retained firefighters on call have their own lives so their availability will always differ. It comes down to there not being enough retained firefighters and positions not being backfilled because of the cost. The state government hasn't given Fire and Rescue enough money over the past few years, and we can't operate the way we need to protect the community as a result."
Member for Heathcote, Lee Evans, and Member for the South Coast, Shelley Hancock, were both contacted for comment, but neither had responded by the time of publication.
Mr Drury said he hoped the community would pressure their local MP's to guarantee Fire and Rescue NSW stations would be given the funds they need to remain open around the clock.
"We've been fighting this with Industrial Relations for two years, but at the end of the day the NSW Government can provide the budget, and it's going to take political pressure to fix," he said.
The NSW Government and Australian Government say they funded a $4.5 billion program for bushfire recovery, response and preparedness in NSW. It is not known how much, if any of that money went to frontline fire services.
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