The document estimates that an average annual investment of £1Bn will be necessary over the next 50 years to prevent damage to property and assets, including transport infrastructure.

Forty one percent of transport and utilities infrastructure assets are located in areas at risk of flooding, it says, emphasising the importance of continued investment to protect infrastructure.

It also notes that the impacts of flooded infrastructure can be far more extensive than the immediate water damage, impacting on supply chains, travel and access to key services.

“This report sets out the level of investment we need to consider over the next 50 years alongside the action we need to take to ensure that communities, businesses and vital infrastructure are resilient to flooding and coastal erosion,” said the Environment Agency’s director of flood strategy Julie Foley.

The overall benefit to cost ratio of spending £1Bn a year on flood resilience is nine to one according to the economic assessment. Priorities for spending identified include building and maintaining large scale engineered defences, natural flood management techniques such as planting trees and property flood resilience for homes.

The findings also indicate that the number of properties in the flood plain is set to almost double over the next 50 years. Continuing to make the right planning decisions will be vital to keep pace with population growth and climate change, the report says.

Later this year the Environment Agency will consult on its new Flood and Coastal Erosion Risk Management Strategy.

In addition the National Infrastructure Commission has this week launched a consultation to gather views as part of a new study into the resilience of the UK’s infrastructure network.

The study will examine what actions the Government should take to ensure that infrastructure can cope with future changes, disruptions and accidents, ranging from increased risks of flooding, to increasing dependence on digital technologies.

NIC chairman Sir John Armitt said: “Our latest study will examine how best to ensure that our infrastructure systems are fit for managing shocks or disruptions they might face.” The consultation will run until 1 April.

(Photograph: Bigshot D3 - iStock)