A confidential report assessing the government’s insurance liabilities during the next 20 years looks at risk levels for state-owned schools, hospitals, roads, bridges and railways.

Timber and plasterboard buildings have the greatest risk of damage.

The report says while climate change projections point to more frequent and severe inundation and surges, the impact on assets is expected to be minimal in comparison to the impact from bushfire and river flooding in other areas.

It also says changes in weather patterns would increase the risk of infrastructure failure foundations, degradation of roads and stress on rail lines.

Coastal areas, including the south-west, are likely to experience up to one per cent increase in winter rainfall by 2030, the report says. 

Environment Victoria obtained the Victorian Managed Insurance Authority’s report under freedom of information following the threat of legal action.

According to the environment body’s chief executive Kelly O’Shanassy, increasing insurance costs will ultimately be borne by taxpayers.

“Scientists, progressive businesses, Victorian communities and now insurance experts all point to the risks posed by climate change to Victoria, yet the Baillieu government continues to neglect its obligations to reduce greenhouse pollution from coal plants, factories and transport systems,” she said.