Community support is vital for any planned relocation of homes at high risk of natural catastrophe damage, and there is no one-size-fits-all approach, a new IAG report says.

The study gives a framework for governments and residents considering moving properties or whole communities that are at high risk of suffering devastating floods, bushfires and cyclones.

The strategy was found to be particularly economically viable in higher risk locations, and MD and CEO Nick Hawkins says Australia has the ability to prevent future loss of life and property and suffering from natural disasters with sustainable long-term solutions.

Deloitte estimates natural disasters will cost the Australian economy on average $73 billion annually by 2060.

“It is our hope that funding for mitigation will be expanded to include planned relocation for the communities most at risk, and that the recommendations in this report will be realised and undertaken with urgency,” Mr Hawkins said.

The report calls for development of National Guidance on planned relocation and funded integration support measures for relocated residents.

This should be coordinated by state and territory government agencies, it says, and high-risk locations should be proactively identified – and adaptation plans developed – before a natural hazard occurs.

IAG is urging that government funding be formalised, legislative frameworks for accelerated approval be established, and that the outcome of large-scale relocation implementations be reviewed to help inform new relocation frameworks.

After record floods last year, the Queensland and NSW governments are undertaking large-scale retrofitting, raising, and relocation. The two schemes provide around $1.5 billion in flood resilience funding, including for voluntary purchase of high-risk properties.

Those most at risk may be eligible to relocate their homes.

Planned relocation would avoid the cost of annual damage to residential property and roads, bridges and parks, the report said, as well as the costs of clean up, emergency response, and "intangible” community impacts such as flood-induced anxiety.

There may be opportunity for government-subsidised financing for people being relocated, IAG’s study says, and vacant dwellings left behind should be demolished and vacated land repurpose, as community open space for example.

“There may be numerous dislocated spaces that may prove challenging to providing meaningful use,” it said.

The costs of planned relocation were found to be highly variable depending on the design of the scheme – buy-back or community relocation – as well as location. Larger schemes had economies of scale.

“The economic feasibility is highly dependent on the scale of the scheme and the annualised damage per dwelling in the location being assessed,” the report said.

“In all locations the buy-back scheme represented a relatively more cost-effective option than the community relocation scheme. This is due to the relatively higher cost of land sub-division and house construction than the purchase of the equivalent number of properties.”

The report says both schemes were generally viable – planned relocation where the flood risk and potential damage to property is high.

"Australian communities must … understand and plan for relocation when the risk to life and safety exceeds a safe threshold,” Mr Hawkins said.

“This is a difficult discussion for communities to have. Supporting them must be at the heart of this process.”

The report makes seven recommendations:

• Develop National Guidance on planned relocation
• Prioritise and fund integration support measures for relocated residents
• Coordination by State and Territory government agencies
• Proactively identify high-risk locations and develop adaptation plans before a natural hazard occurs
• Formalise government funding
• Establish legislative frameworks for accelerated approval
• Review the outcomes of large-scale implementations to inform frameworks

See the full report here.