Experian releases its latest flood report

Heavy rainfall continues to be predicted through to mid-July and, with the total cost of flood claims potentially reaching £1 billion, Experian, the global information solutions company, releases its latest flood report to help the insurance industry understand the different flood scenarios.

David Murby, Managing Director of Experian’s Insurance Services division, said: “Last month turned out to be the wettest June on record and resulting claims are also expected to reach an all time high.

“As widely reported, there have been numerous serious flood incidents across the United Kingdom, most notably around Belfast and in a band across England stretching from the lower and middle Severn valleys in the Midlands up to South Yorkshire, Humberside and Lincolnshire. This has led the government to pledge a significant increase on flood defence spending, but the insurance industry also needs to take steps.

“Understanding and knowing exactly where and how a flood is likely to occur and being able to assess the potential level of damage and costs beforehand is an insight that is invaluable for insurers.”

Experian’s latest flood report highlights how the flooding has occurred in three different scenarios:

Low volume catchments: The rate at which rain fell in rural settlements located in narrow steep-sided valleys, was faster than the soil could soak it up and the local watercourses could carry it away. As a result, the valleys filled with water, quickly causing flooding and damage to properties. For example, Hampton Loade, which can be found in the Severn valley in Shropshire, saw half of the average rainfall for June in just forty-five minutes. With the saturated ground unable to hold any more water, torrents of rainwater flowed down the steep valley sides washing away a road, a section of railway track and damaging properties.

Broad valleys: Settlements in broad low-lying valleys did not experience the extreme downpours. However, these areas were inundated as a result of the local rivers and channels not being able to withhold the water travelling from areas further upstream. For example, the banks of Ea Beck and the River Don could not hold the abnormally large amount of water flowing downstream from the areas of heavy rainfall further inland and, as a result, the village of Toll Bar near Doncaster, which lies at only five metres above sea level, flooded. Three quarters of the properties in Toll Bar have been flooded and with the flat local topography, the water may take a long time to recede.

Flash floods: The storm drains in some neighbourhoods in large urban areas, such as Brightside Lane in Sheffield and Connswater in Belfast, were not designed to cope with such high volumes of water in such short periods of time. Rainwater, which would have normally been channelled to the local river through the drainage network, instead ran across concrete and tarmac to inundate streets and houses.

These areas are classed as high risk of flooding within Experian’s Flood Perils model, combining data from a number of sources, including the Environment Agency, the Centre for Ecology and Hydrology, and privately commissioned studies, which is a valuable tool for insurers.

The Perils model can be used to precisely quantify the level of risk exposure for flood at postcode unit level. This enables effective risk management by comparing current and historic claims experience, to identify whether a postcode is in a flood zone, near a flood zone and would benefit from some form of flood defence in between it and the source of flooding. It also enables insurers to estimate the likely relative cost of flooding from postcode to postcode.