The Environment Agency is releasing new maps of flood risks across the country for the first time today.
The maps, which could cause a 15 per cent drop in property values in vulnerable areas, will enable householders to find out whether their homes are at low, moderate, or high risk of flooding.
Homeowners in areas at high risk of flooding could face considerable increases in insurance premiums as a result of the maps being made public.
The internet map, available on the Environment Agency website
, uses new and more sophisticated techniques and information is no longer based simply on postcodes. The insurance industry has welcomed the new maps.
John Hollis, home insurance manager at MORE TH>N commented: "We are able to pinpoint risk right down to the postcode level which means that thousands of homes previously considered at risk of flooding by the insurance industry can now get better deal.
"We urge the rest of the industry to follow suit for the sake of homeowners across the country."
Around 100,000 homes have been moved out of the at-risk zone, although 1.8 million homes still remain in the one-in-100-year risk of a flood category. Places deemed to be at "significant risk" of flooding are calculated to have a 1 in 75 chance of flooding each year.
The likelihood of flooding in a particular area is calculated using predicted water levels and by taking the location, type and condition of flood defences into account. However, it does not take into account any previous flooding in an area.
The chairman of the Environment Agency, Sir John Harman said: "Flooding is a natural phenomenon that will become more frequent as climate change leads to more extreme weather conditions. Find out whether or not you and your property, your family and friends are at risk from flooding and decide what action you need to take - don't leave it too late."
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