Paul Brown, environment correspondent22 April 2004
Risks of flooding are growing to "unacceptable levels" because of climate change with up to 4 million Britons facing the prospect of their homes being inundated, according to a report to be published today by the government.
The report by the Office of Science and Technology gives the most chilling picture yet of how global warming will affect the lives of millions of Britons over the next half century.
Compiled by 60 experts under the leadership of the government's chief scientist Sir David King, it shows that many towns in Britain are threatened by rising sea levels, river flooding and the overwhelming of Victorian drains by flash floods.
The report, Future Flooding, looks forward to 2080 but says that the threat is already growing and most of the worst of its predictions will have happened by 2050.
As a result it is vital to start planning new defences and making long-term decisions now to prevent future disasters. Sir David warned earlier this year that global warming was a greater threat than terrorism.
New "green corridors" need to be created in cities as "safety valves" into which floodwater can be channelled, the report says. In some cases abandonment of parts of urban areas, with councils buying up properties to create new open areas to take flood water, will be necessary.
"Some structures such as oil refineries could be relocated [inland]. However, other assets such as coastal towns will be difficult to relocate.
"In Wales and other parts of the UK, erosion could threaten beaches and therefore tourism."
The report puts a question mark over John Prescott's cherished plans to develop the Thames Gateway with 90,000 new homes, and the whole area east of London which is at or below sea level.
The report says that in all planning flood risks must be taken into account. Space must always be left to allow for river and coastal floodwaters. In the Netherlands some developments are allowed if they are on stilts and have an escape boat.
The report is the most comprehensive undertaken into the risks of flooding in the UK, and probably the world, Sir David says, and shows that properties will become uninsurable and many can expect at least a one-in-10 chance of being flooded every year.
Towns on the east coast which suffered in the floods of 1953 are in the area of highest risk, but the danger to Britain's older cities with Victorian sewerage systems is a newer problem. Drains are in danger of being overwhelmed, spilling water and sewage into homes, as well as being knocked out for weeks at a time - as happened in recent floods in central Europe.
The government has prepared an extensive response to the report pointing out that the Environment Agency is already looking at a replacement for the Thames Barrier, which is likely to be overwhelmed sometime after 2030. Higher sea walls along the embankment into London will also be needed.
But the government will point out that there is no legal obligation to defend property or land at all. "The aim is to reduce the risk of flooding or coastal erosion where it is sustainable to do so and where the proposed defence is economically, technically and environmentally sound."
http://www.guardian.co.uk/print/0,3858,4907459-110970,00.html
