Insured losses from floods have increased from $US1-2 billion in 1970 to $US15 billion in 2011, according to a Swiss Re report.

It says an estimated 500 million people are affected by flood every year, more than any other type of natural catastrophe.

Swiss Re Group Chief Underwriting Officer Matthias Weber says the report aims “to raise greater awareness of floods, their risks and the role of insurance in addressing them”.

“We show what it takes to tackle the challenges in flood insurance and what successful solutions might look like for homeowners and companies,” he said.

The report highlights how the rising costs of floods create challenges for the insurance industry and place the economic viability of flood insurance under scrutiny.

Head of Flood Jens Mehlhorn, who is the key writer of the report, says the $US12 billion ($11.58 billion) in insured losses in Thailand highlights the destruction floods can cause.

“The insured losses corresponded to 1800% of the country's total annual property premium – and this emphasises the difficulties the industry faces in creating an economically viable approach to flood insurance,” he said.

The report considers ways of building adequate “insurance populations” to share flood risk, how insurers can advise on risk-minimisation strategies such as levees, and national programs that meet the challenge of providing flood cover.

After the Thai floods inundated factories supplying vital components to a number of global industries, Swiss Re has now identified clusters of globally relevant industries in flood-prone regions that can cause extreme losses through supply chain interruption and decreased manufacturing productivity internationally.

Swiss Re has also launched a flood app for iPad. See Swiss Re launches flood risk app.