The region's farmers insist they are doing their bit to combat flooding as research finds 90pc of floodplains in England are not doing their job.

The warning comes in the Changing Face of Floodplains report, which says more homes and businesses are now at risk of flooding because of their lack of effectiveness.

Intensive farming and increased urbanisation has changed the state of alluvial plains, with 65pc found to have smoother man-made surfaces and 9pc lost entirely to towns and villages, said the report.

Increases in flash rainfall, in which large volumes of water fall in a short period of time, have put pressure on drainage systems and led to incidents such as the floods which hit Breckland and other parts of Norfolk in June last year, it added.

The research, which was conducted by the University of Salford in partnership with Co-op Insurance, looked at Cumbria and the damage it suffered during Storm Desmond in 2015.

But Rob Wise, the National Farmers' Union (NFU)'s regional environmental adviser, said while farming had impacted flood plains over the centuries, modern agriculture was attempting to steady the flow.

He said: 'It is fair to say that agriculture, along with urbanisation and everything else, plays its part in increasing water flows and therefore farmers are as interested as anybody else in slowing the flow of water. We are involved in projects in Norfolk and elsewhere to do that. In Broadland we have worked to put in systems which capture water at corners and edges of fields that hold up the water flow in heavy rainfall events.'

Much of the control of water flow is done through natural flood management, by planting trees and vegetation to slow it down, but the NFU said this had to be part of a wider set of measures.

The University of Salford's Dr George Heritage, who conducted the study, said: 'The speed at which floodplains have deteriorated is a cause for great concern. Given the fact that UK weather will consist of more storms in years to come, if we don't act now to restore these floodplains, what we saw with Storm Desmond [...] will be a more frequent occurrence.'

Dr Heritage said the research aimed to inform thinking across the industry.