'London will flood, and flood badly'

Mel Gosling, of business continuity specialists Merrycon Ltd, said it was not a question of if, but when, such an event would impact on the city. He also claimed that many London based-firms were ignoring the issue when it came to their continuity plans.

His comments were made one year after the floods that devastated New Orleans following Hurricane Katrina. Mr Gosling said he had become "increasingly concerned" about the effect of a similar event in London.

Writing for Continuity Central, he said: "London will flood, and flood badly. It's not a question of if, but when. And when it does, the effect could be devastating to the UK economy unless the organisations that operate in London, be they in the government, health, industry, finance, or other sectors, have realistic, appropriate and effective business continuity plans."

Compulsory participation

Mr Gosling highlighted how a resilience exercise conducted in the City of London last year, to test the financial market's planned response to a major business continuity crisis, had failed to look at what would arise from major flooding in the City.

He also warned that he had come across a number of London based firms potentially at risk from flooding, whose contingency plans failed to cater for a catastrophic flood.

"They are not alone in this. Large numbers of organisations in the City of London, for example, have disaster recovery sites in Docklands," he wrote. "For those of you that are not familiar with the geography of London, Docklands is an area to the east of the City of London in low lying land on the banks of the River Thames - and yes, if the City floods, so does Docklands!"

He called for a thorough flood resilience test to be carried out in the capital, for business participation in such an exercise to be made compulsory, and for the results to be made public.

'Bring back wetlands'

Meanwhile, a leading academic has called for a 165ft belt of saltmarsh along parts of Britain's coastline to help reduce flooding.

Dr Tom Spencer, of Cambridge University, said the loss of coastal ecosystems along the Thames and much of Britain increased the risk of flooding, and that re-introducing wetlands could help protect people and property from rising sea levels and severe storms.

He said saltmarshes in front of a sea wall would make a "significant difference" to wave heights. He added that coastal zone ecosystems - such as the saltmarshes and mangrove swamps - act as natural buffers to wave energy along coasts and estuaries.

Dr Spencer pointed to the loss of more than 40% of the intertidal zone along the Thames since Roman times, leaving a deep channel constrained by more than 185 miles (300km) of sea wall and defence structures. The loss of wetland habitats along the estuarine Thames could lead to a rapid flood tide moving up the river during a serious storm surge, he said. This was because there was less storage for floodwater.

Dr Spencer, who is a senior lecturer at the Department of Geography at Cambridge, was presenting his research to the annual conference of the Royal Geographical Society in London.