The good news is that 2017 saw just about average rainfall when worked out across the whole year (MET office statistics), so no rising rainfall to worry about … or is there?
As we all know, sometimes it doesn’t just rain, it pours and, despite statistics which demonstrate average rainfall when measured across a year, the UK frequently sees deluges which deliver rapidly rising water levels in some areas, in very short timescales. These episodes of wet weather can cause surface water flooding and localised drainage flooding, as well as present extreme weather issues such as rivers bursting their banks.
A good example of this is Storm Desmond in 2015, which saw a deluge of 34 cm of rain into the Cumbria area within a single 24 hour period – a rainfall record.
But although this area is particularly notorious for flood issues, this is not the only vulnerable spot in the UK. In fact, according to the Environment Agency, approximately 5.9 million properties across Wales and England – that’s one in six homes – are at risk of flooding.
So where are these homes, and why are they at risk?
- Coastal locations
Coastal erosion offers a specific risk to homes. Tidal flooding, particularly in a century that’s already seeing rising sea levels, can result in the gradual destruction of sea defences and the loss of permanent homes to the sea.
Areas of the UK particularly vulnerable to this type of flooding include:
- East coast areas, particularly Peterborough, Hull and Great Yarmouth
- Kent and Sussex coastal areas. Some areas have been protected through “managed realignment”, which means that some areas of land are surrendered back to the sea, in order to reduce the risk of flooding in alternative areas, a strategy recently used in Medmerry in West Sussex.
- Riverside locations
Many of the UK’s oldest, and even more recent settlements were built on riversides. Unfortunately, these locations are doubly at risk when the weather turns wet and the seasons stormy: tidal surges coming upriver from the sea, as well as rivers bursting their banks from significant rainfall over a short, sudden period of time.
Areas of the UK at particular risk include, but are by no means limited to:
- Somerset – with Glastonbury is at risk of flooding from rivers with floods at the music festival being notable and regularly reported on example. Bridgewater and Highbridge, ancient names giving clues to environmental factors which regularly affect them.
- Kent: New Romney, Gillingham, and Rochester.
- Essex: Burnham-on-Crouch.
- Norfolk: Great Yarmouth.
- Cambridgeshire: Peterborough and Holbeach.
- Lincolnshire: Woodhall Spa, Boston, Skegness, Scunthorpe, Sandtoft.
- Yorkshire: Knottingley and Hull.
- Floodplain locations
Whilst our floodplains are often beautiful, they are extremely vulnerable to flooding from heavy rainfall causing rivers to flow fast downstream and bursting banks. The prevalence of agriculture in floodplains has also had an effect on risk, through the removal of natural flood protection, such as hedgerows. Cumbria is an area known for considerable risk (Guardian).
- Surface water
Surface water flooding is caused when flooding through downpours or other flood damage to drains (such as rivers bursting their banks and flooding drainage systems) affects drainage infrastructure. These events are often known as “flash flooding” and often affect urban areas, due to the high demand on drainage systems.
Areas frequently affected in this way include:
- Lincoln, Gainsborough, Boothby Graffoe, Cleethorpes in Lincolnshire.
But wherever you live, it’s worth noting that despite ‘average’ rainfall in 2017, 2018 has already seen the Environment Agency issue a warning that flooding in the UK is likely to become more frequent, thanks to climate change.
How can you find out your level of risk?
- Checking Gov.uk’s online Flood Map for Planning tool, to research any identified flooding risk to an area, based on a postcode search. This tool is linked to the Environment Agency research and data.
- Searching the interactive flood map provided by Friends of the Earth.
- Looking more closely at the flood risk to a particular property using the Gov.uk’s Check Flood Risk service. This includes information on applying direct to the Environment Agency for data relating to a property, which can be extremely useful for insurance purposes and when deciding whether to purchase or rent a property.
Understanding what the statistics or research information is telling you about your level of risk is also important. For example:
- The Gov.uk postcode checker offers a clear indication of levels of risk according to zones:
- Zone 1: low probability of river or sea flooding (less than 1 in 1,000 annually).
- Zone 2: medium probability (between 1 in 10 and 1 in 1,000 annually for river flooding; between 1 in 200 and 1 in 1,000 annually for sea flooding).
- Zone 3a: High probability – 1 in 100 or greater annual probability of river flooding; and 1 in 200 or greater annual probability of sea flooding).
- Zone 3b: Functional Floodplain where strategic risk management and assessment is in place.
Results are offered in a visual map and text-based form, which immediately tells you the level of risk – dark blue areas of land are at risk of sea flooding) and makes it easy to tell if you are living (or proposing to live) in an area benefiting from flood defences.
- The Environment Agency classifies areas with Medium and High risk of flooding, which means:
- High risk: A more than one in 30 chance of the property being affected by flooding across one year.
- Medium risk: a chance of between one in 30 and one in 100 that the property may be affected by flooding in a given year.
#3: Take action
Once you know the level of risk to your wider area and immediate locality, it can be possible to minimise your overall risk by taking preventative action:
- Learn about flood planning for your local area (with additional research through your local council, the Environment Agency’s flood map for planning).
- Keep checking in with the Gov.uk services, and using tools such as their:
- Protect your property by buying or hiring flood defences or making adjustments to the construction of your home.
- Asking for professional advice if you think your property is at risk of flooding or if you would like to find out more about flood prevention.
- Checking with insurers to ensure you’re adequately covered.
* Data from Friends of the Earth and the Environment Agency.