Flood damage estimated at £1.1bn a year is being prevented by the UK’s network of river barriers and defences, according to research.
The Association of British Insurers (ABI) says it is the first time the financial contribution of river defences has been quantified.
The modelling, based on thousands of simulations of weather events with and without flood defences, emphasises the value to UK homes and businesses of flood defence spending and the importance of government investment, particularly for flood-prone locations such as Cumbria, Yorkshire, Somerset and the Welsh valleys.
The Environment Agency recently warned that whole communities may need to be moved away from coasts as a result of flooding caused by the climate crisis.
The research, published on Wednesday and commissioned by Flood Re and conducted by Risk Management Solutions, suggested inland flooding would, on average, cost almost three times more a year without the defences – a bill of £1.8bn rather than £700m across the whole of the UK.
In England, the government spends about £600m a year on building and maintaining flood defences. The Environment Agency has called for spending on flood defences to increase to £1bn as the nation prepares for warming of up to 4C above pre-industrial levels.
Closer examination of what happened in Cumbria in December 2015 shows the flooding caused by Storm Desmond would have done damage worth three-and-a-half times as much without river water defences – £2.8bn rather than £600m.
James Dalton, the ABI’s director of general insurance policy, said: “The human cost of flooding is immeasurable, putting lives at risk, causing families great trauma and pushing some businesses to the brink. Flood defences are an essential part of the protection system which prevents and minimises the trauma caused by flooding as much as possible.
“Faced with the growing threat of climate change, there is a clear financial argument for investing in flood defences. The barriers, walls and natural defences that currently prevent greater damage being done by the UK’s rivers during times of extreme weather make economic sense, but they must keep pace with the threat if they are to continue being effective.”