Over the past few years, extreme weather has caused widespread destruction to homes and businesses across the UK. In early 2024, severe storms brought record-breaking rainfall to parts of the North and Midlands, leaving thousands without power and causing billions in flood damage. Southern England and Greater London have also faced rising water levels, with flash flooding in summer 2024 overwhelming local drainage systems in several boroughs. As we move further into 2025, experts warn that wetter, more unpredictable winters are now the norm, meaning the risk of destructive flooding remains high. In the drainage industry, we’re already preparing for what could be yet another challenging and waterlogged winter season.
Should London be worried about increased flooding?
4.6 stars
view reviewsRapid response time
We'll be with you in 60 minutes or less!
Emergency assistance 24/7
We are open 7 days a week
Fully transparent cost breakdown
Our quotations are clear and concise.
Comprehensive aftercare
If your drain blocks again within 28 days, we'll unblock it, free of charge.
What’s causing the increased flood risks?
It is too easy to blame a flood on winter weather and increased rainfall without looking at the underlying issue; what is causing the volatile weather and increasing the amount of rainfall, and why are we so ill prepared for heavy rain?
Global warming
Global warming is one main concern for increasing flood risks, with the surface temperature of the Earth increasing year by year to an unsustainable temperature for the environment. This increased temperature has led to the melting of the ice caps which has caused the sea level to rise, having a knock-on effect for major rivers, such as the river Thames.
The increased water in the River Thames combined with the increased rainfall from the evaporation of the oceans, means that a flood risk is ultimately much more likely for the surrounding areas as the river bank cannot meet the demands of more water, overspilling the excess to the streets and roads surrounding it.
Storm surges
Storm surges are usually not accounted for when flooding in London happens, but their presence is a very real indication of the amount of damage that global warming is causing to our Earth. Surges are caused by strong winds pressing down the sea in areas of low atmospheric pressure which causes water to be sucked upwards and forming a hump when two winds collide. The hump then causes a strong tidal movement that can impact the sea levels for miles around. Most of the storm surges that reach the UK originate from Canada, travelling across the Atlantic Ocean and propelled across the North Sea if there is a northerly wind.
As the storm passes through smaller and smaller spaces, the size of the hump increases, putting more pressure on the east coast of England and funneling into the estuary of the River Thames by the momentum of the Earth spinning on its axis. This increased pressure causes London flooding around the River Thames as the surge makes its way inland.
High tides
High tides are a natural occurrence that happens as the gravitational pull of the moon moves the water from one side of the ocean to another, but when a high tide coincides with heavy rainfall or a storm surge, flooding is a sure thing. The excess water from the high tide will flow into the adjoining rivers, causing them to burst their banks and wreak havoc on the surrounding areas.
Lack of drainage
Unfortunately, London is still not adequately equipped to deal with increased levels of water, with the current drainage systems not being suited to quickly dispose of the wastewater before it begins to flood. There are projects that are being constructed to fix this though.
The Thames Tideway Tunnel
It’s too easy to blame flooding on heavy rainfall alone, without considering the deeper causes. Emerging from a mix of climate change, rising sea levels, and outdated infrastructure, London’s flood risk is intensifying. In response to these threats, the long-awaited Thames Tideway Tunnel, London’s £4.5 billion ‘super‑sewer’, became fully operational in February 2025 and was officially inaugurated by King Charles III in May 2025. The 25 km tunnel has already stemmed 95 % of storm sewage overflows, capturing vast volumes of polluted water that would otherwise have flooded into the tidal Thames during heavy rainfall. By intercepting up to 1.6 million m³ of combined sewer overflow, it dramatically reduces the chances of flooding around the Thames, and improves water quality in a major way in our capital city.
Image from www.tideway.london/the-tunnel
Protecting your property against flooding in London
With the risk of flooding becoming more common in London, we’ve got some tips on protecting your property from the damage:
- Use sandbags to divert water away from your property
- Raise the level of your door step
- Use a waterproof sealant on the exterior of your property
- Install flood resistant windows
- Make sure your pipes are fitted with non return valves to prevent water coming up your drains and into your home
- Cover your vents and drainpipes
- Raise the height of your power sockets and electrical items
- Switch carpets for tiles
- Install a sump pump to pump overflowing water out of the basement of your home
Following these safety precautions should help limit the damage to your property. If the flooding in your area is particularly bad, however, you can call in a drainage expert to cleanup the flooded water surrounding your property to prevent your premises becoming damaged beyond repair, or as a precautionary measure to remove the flooded water before it has entered your premises and caused internal as well as external damage.
Speak to an expert today
Core Services
Find your local engineer today