Swathes of land and thousands of properties in west Norfolk, Suffolk and the fens will be at greater risk of flooding over the next 50 to 100 years, according to a new report.

Swathes of land and thousands of properties in west Norfolk, Suffolk and the fens will be at greater risk of flooding over the next 50 to 100 years, according to a new report.

The effects of climate change, increased urban development and land use will increase the chance of flooding in areas around King's Lynn, Downham Market, Thetford, and Bury St Edmunds, says the Environment Agency.

The agency is now recommending further flood defence work is undertaken in the Norfolk and Suffolk towns most at risk, according to the latest draft of the Great Ouse Catchment Flood Manage-ment Plan (CFMP).

But officials are also calling on residents and businesses to help shape the final plan as part of public consultation that will run until the end of March.

The report comes almost 60 years after the Great Ouse, Welland and Nene rivers burst their banks after a winter thaw and heavy rain, which caused 6ft deep floods across vast areas of the fens.

The agency says that more than 33,000 people and 16,000 properties would be at risk in the event of a flood of a “one-in-100 years” magnitude.

The area affected along the Great Ouse river and its main tributaries, stretches from Northamptonshire to Milton Keynes, Bedford, Cambridge, Mildenhall, Bury St Edmunds, Thetford, Watton, Swaffham, Downham Market and King's Lynn, before finishing at the Wash.

But predicted sea level

rises, more rainfall, a 20pc increase in peak river flows, and further housing and industrial development will affect an estimated

56,539 people and 29,488 properties over the next

50-100 years, says the CFMP report.

Lucy Harper, from the Environment Agency, said that King's Lynn, North Runcton, and the fens had been identified as high priorities for future flood management work.

Downham Market, the River Lark at Bury St Edmunds

and Little Ouse at Thetford have been categorised as medium priorities.

“We are running into the realm of flood risk management rather than flood defence and focusing on the best places to spend money to achieve maximum benefits for the maximum number of people,” she said.

“We are not identifying specific measures to manage flood risk, but will identify where we should undertake further work. It could be that we have to do more to stop building in the floodplain or improve flood warning services.”

The Environment Agency is recommending that storing water in the upper areas of the catchment would help reduce the chances of similar flooding in the fenland area in the future.

A public exhibition on the Great Ouse CFMP will take place at the Wildfowl and Wetlands Trust Centre at Welney on Wednesday between 1pm and 6pm. Residents can still air their views on the plan until March 31 and can find out more by visiting www.environment-agency.gov.uk.