Hundreds of thousands of Australian homes will be at risk if sea-levels rise as predicted in a report by environmental experts.
The Climate Council has warned half of the nation's coast is vulnerable to a one-metre sea rise by the end of the century.
The damage would extend to hospitals, rail lines, power stations, roads, commercial properties and almost 250,000 homes within 200 metres of the coastline.
Restaurants along Sydney harbour could have water "sloshing in every day", report author Professor Will Steffen said.
Australia's tourism industry would suffer.
"We have a lot of important coastal ecosystems...many of those will be trapped in a coastal squeeze caught between sea levels rising and coastal development," report researcher Professor Lesley Hughes said.
"So there will be nowhere for them to go."
The council - which replaced the Climate Commission which was abolished by the Abbott government - predicts sea levels will rise by between 40 centimetres and a metre by 2100.
However, it says a 1.1 metre increase is not out of the question - an outcome that would put $226 billion in infrastructure at risk of inundation.
More than $200 billion of infrastructure is at risk if the worst-case scenario comes true.
Report author Professor Will Steffen urged Australia to cut its greenhouse gas emissions, saying failure to do so would be "extremely painful and expensive".
"The potential threats to Australia, where the majority of us live on the coast are disproportionately large," he said.
"We're talking about the loss of beaches, property, infrastructure and commercial assets worth billions to our economy."
Coastal NSW, Queensland and Victoria would be hardest hit by the rising waters and associated storm surges.