Scientific forecasts on flood risk and how it might affect your property

The risk of flooding in the UK is rising year on year, thanks to the combined effects of climate change, a growing population and pressures on our green spaces.

According to a study, which was published by scientists at the University of Bristol earlier this year, flood damage could rise by more than one fifth over the next 100 years.

It is a warning sign of how things might be for our future generations, but the researchers offer a glimmer of hope, saying that if all countries, which include the UK, fulfil all the ambitious pledges they signed up to at COP26, it could help to mitigate the risk, keeping flood losses below 5% above recent historical levels.

However, if the COP26 and net zero promises are not collectively met, the study warns the annual cost of flooding in the UK over the next century could grow by between 13% and 23%, depending on different levels of climate extreme projections.

Another forecast warned the estimated cost of a 200-year flood event could increase to as much as £5 billion (42% higher than today), but if no action was taken to reduce carbon emissions, that figure could rise further – up to 87% in average annual losses to residential properties, as well as a 120% rise in the cost of surface water floods, which would hit the south and east of the UK especially.

The Bristol team believe the cost of flooding has been increasing in the UK by 1.4% each year since 1990 and now costs about £740 million of every year. However, other figures have claimed the annual flood damage in the UK costs about £1.3 billion.

Recent historical weather changes

The World Meteorological Organization, the United Nations’ weather agency, warned in 2021 that weather disasters are striking the world four to five times more often and causing seven times more damage than they did in the 1970s.

And Met Office records in the UK have shown that since 1910, there have been 17 record-breaking months of rainfall. Nine of these have been since 2000 – and as intense storms are becoming more frequent, sea levels are also rising because of climate change.

How much does flooding cost every year?

The management of flood risk across the UK is a critical issue. The Environment Agency’s flood and coastal erosion risk management (FCERM) risk management report estimates the economic losses* from flooding between November 2019 and March 2020 were about £333 million, with about with about 4,630 properties affected.

However, if flood defences had not been in place in critical areas, the department says the floods could well have cost an extra £2.1 billion. It adds that for every £1 spent on protecting communities, £5 in property damages are avoided.

February 2020 was England’s wettest ever and the UK’s fifth wettest winter on record. However, Environment Agency flood schemes protected 129,600 properties even though water levels were higher than the summer floods of 2007 when 55,000 properties flooded.

And when it comes to insurance claims resulting from floods, the Association of British Insurers says the average household claim is about £31,000, while for a business it is about £70,000.

Flooding is costing us all.

It’s getting wetter

According to the Met Office, for the most recent decade (2009-2018) UK winters have been on average 5% wetter than they were between 1981 and 2010 and 12% wetter than the period 1961-1990. Summers in the UK have also been wetter, by 11% and 13% respectively.

Mark Hoban, the chair of Flood Re warned this summer that there will be “more persistent” widespread flooding in the UK, adding that more than three million homes in urban areas were at risk of flash flooding.

Crucially, low-income households are among the most at risk because estimates show they are eight times more likely to live in tidal floodplains than those more affluent households, while 61% of low-income renters are more at risk financially because they do not have home contents insurance.

The impacts of flooding

Risk mapping and modelling are essential tools to gather the data and evidence that underpin every investment decision that risk management authorities make. Locally this could be about spatial planning and prioritising flood and coastal infrastructure, while at a national level the tools enable scientists and risk experts to quantify the overall scale of risk.

There are myriad knock-on impacts when it comes to flooding and increased flood risk.
These are to do with:
Improving climate resilience in buildings since climate change is baked in for some decades, at least.
Recognising that some core consumer financial products also need to be made more resilient so they protect users:
Flood insurance – homeowners and businesses seeking insurance need to gain assurances from the industry that it will continue to offer cover for decades to come so that homeowners’ assets are protected
Mortgage terms – what happens to the UK custom of moving mortgages for short-term fixed deals if flood insurance fails to meet the demand? Is a mortgagee in breach of the insurance condition able to re-mortgage?  Will the lender foreclose on a loan if the collateral is not protected by a third party?
In the public sector, schools, hospitals, transport infrastructure and so on need the same type of resilience to ensure they are protected as much as possible from flood damage.

These are the types of questions that financial services need to examine in detail over the coming years as we grapple with the effects of climate change and flood risk.

GeoSmart Information

GeoSmart’s FloodSmart Analytics (FSA) can assist at the first step in screening properties and then analysing what type of flood risk is present – or will be likely with climate change. Being ‘flood smart’ starts with being informed of the flood risk.

As a highly regarded independent UK-based flood-risk adviser, whose data have been used in millions of house-buying transactions over the years, we work with large organisations, utilities and with governmental bodies to guide advisers, consumers and regulated firms as they improve their climate risk due diligence related to flood risk at property level.

FloodSmart Analytics, our flood product, provides detailed risk analysis of individual properties and includes climate change scenarios, enabling users to make risk-based decisions that allow more information depending on the degree of concern – perhaps including a view on mitigation options.
As the Environment Agency, DEFRA and Flood Re have advised consumers to “Be Floodsmart”, Geosmart Information’s new FloodSmart Analytics is ideally placed to provide the necessary flood risk data.

To find out how FloodSmart Analytics can support you, telephone our expert team on 01743 297065 or email

  • Assessments of economic costs estimate costs at a national level, rather than an individual household/business or local area level. Economic costs take into account factors such as transfers (eg. taxes and subsidies), betterment, and displacement of economic activity from one part of the economy to another.