Insurance rise fears over Shropshire flood-risk map

The improved map from the Environment Agency shows, for the first time, homes and businesses at risk from surface water flooding, as well as those at the mercy of rivers or the sea.

Insurance companies will now be able to use the information to re-evaluate a home's chances of being flooded – and could increase premiums as a result.

But some homes could also see their premiums fall.

• Environment Agency Live Flood Warning map - updated every 15 minutes

The EA says about three million properties in England are at risk of surface water flooding, but before the agency used cutting-edge technology to create the map, that figure was thought to be as high as 3.8 million. Surface water flooding happens when heavy rain does not drain properly.

The new map shows that areas in Shropshire which have been protected by flood barriers are still at risk from surface water flooding.

In the infamous floods of 2000, the centre of Shrewsbury was cut off with access roads under feet of water. The area around Frankwell was particularly badly hit, leading to a £6 million flood defence scheme designed to protect more than 70 homes and businesses.

Those properties, which now include Theatre Severn, are said to be at "high risk" from surface water flooding.

But even areas not near any rivers are said to be at high risk. The map shows that even areas like Telford's Stafford Park industrial estate, just off the M54 motorway, and parts of Telford town centre are also at risk.

Graeme Trudgill, head of corporate affairs at the British Insurance Brokers' Association, said: "A new surface water map from the Environment Agency will provide a lot more information and could alter a homeowner's risk profile."

BIBA said some insurance companies were already adjusting the risk profiles of some properties.

The association said one small business moving to a new location just next door was quoted a 600 per cent rise in its excess fee for buildings insurance from £350 to £2,500 – despite there being no history of flooding.

But bigger insurance firms said the amount of information they collected meant the new mapping system would have no affect. A spokeswoman for Halifax, one of the country's leading insurers, said: "We currently use detailed and reliable data that includes the risk of groundwater flooding, therefore the new flood map will not affect the way we assess flood risk."

About five million properties are at risk of flooding in England, including 3,600 in Shropshire and 3,750 in Powys.

Dr Paul Leinster, chief executive of the Environment Agency, said: "Being prepared can save lives, homes, personal possessions and businesses.

"We have used cutting-edge technology to map areas at risk of surface water flooding in England.

"These maps are now among the most comprehensive in the world.

"With one in six homes in England at risk of flooding we urge people to check if they are at risk, and sign up to free river and coastal flood warnings, by visiting the Environment Agency website."

The EA said the new maps would also help local authorities to manage surface water flood risk as required by legislation passed in 2010.

Environment Minister Dan Rogerson said: "We understand the damage and the stress that flooding can cause. That's why we're spending an unprecedented amount of money on protecting communities from flooding and coastal erosion.

"On top of this we have reached an agreement with the Association of British Insurers guaranteeing affordable flood insurance for people in high-risk areas both now and in the future."

Aidan Kerr, head of property at the Association of British Insurers, said: "Accessing accurate, up-to-date information on surface water flood risk will help homeowners and businesses take steps to reduce the often devastating, and expensive impact of flooding."