London floods threat

Radical plans to erect a new 10-mile barrier across the Thames to save London from flooding are revealed today.

The massive embankment would stretch from Sheerness in Kent to Southend. It would be the biggest engineering project undertaken in Britain.

The proposal has been put forward by leading climate change scientists who believe that much of central London could soon be under water if current trends continue. Details of the plan will be revealed at a climate change conference convened by Tony Blair next month.

A key finding is that if the city's existing defences are breached, then Westminster and other parts of central London could be six feet deep in water within an hour. It could mean the end for Big Ben, Parliament and the Tower of London, say experts.

By 2030 it is believed the existing Thames Barrier will be inadequate because London is still sinking at a rate of about 8 inches a century while the global sea level is rising.

A new report says: "Such rises pose a serious threat to human life particularly when considering the high population density of the Thames estuary. The risk of inundation of many central London hospitals adds further to this strain."

Professor Jim Hall at the Tyndall Centre for Climate Research, one of the authors, said: "We wanted to look at the more extreme but still plausible scenarios for sea level rise. The chances of these happening are small but the consequences are so dramatic that we have to prepare for them."

Under the scheme, the barrier would contain numerous gates to allow water to flow in and out of the Thames estuary according to the tides. But engineers would be able to shut the gates if a flood seemed likely.

The plan for the Thames comes as the north of England reels after being hit by torrential rain and gales.

Three people died and two are missing, while hundreds of homeowners are still unable to return to their homes because of flood damage. Carlisle was cut off for several hours over the weekend.