Updated 25 June 2026.
Overnight on 23 June, intense thunderstorms swept across London, and the clear-up is still going on. The London Fire Brigade took around 400 calls from midnight, most of them flooded homes and roads, and reported that Twickenham and Richmond saw a high number of flooding incidents in the early hours. There were flash floods on the roads, travel disruption around Heathrow and on the Elizabeth line and Tramlink, and even a couple of house fires started by lightning. And it is not over: flood alerts have just been issued for Nottinghamshire on 25 June 2026, with more storms expected, so this is a live and widening picture.
If your home or street was caught up in it, you have our sympathy, as there are few things more stressful than watching water come up through your floors. This is a short, practical guide to what happened, why it keeps happening, and the sensible steps that genuinely reduce the damage next time.
It has happened here before: Richmond's 2021 flash flood
This week was not a one-off. On 12 July 2021, heavy rainfall over London triggered significant flooding, and the council's own Section 19 Flood Investigation (the formal report a lead local flood authority must produce after a serious flood) found that Richmond experienced rainfall between a 1 in 10 year and greater event. Crucially, it concluded that surface water and sewer flooding were the most frequent sources of flooding that day, not rivers bursting their banks. That is the same kind of flooding experienced this week, and it is the kind most likely to return.
Why surface water flooding keeps catching us out
Surface water flooding, often called flash flooding, happens when rain falls faster than the ground and the drains can take it away. The water has nowhere to go, so it ponds in low spots, runs off hard surfaces and finds its way into basements, garages and ground floors. It can happen almost anywhere, often far from a river, and it arrives fast with little warning.
It is also becoming more common. As our weather grows more extreme, with heavier, more sudden downpours, our older drainage networks are increasingly overwhelmed, which is exactly the pattern behind both the 2021 and 2026 Richmond events. We have written more about why these extremes are increasing in our piece on El Nino, extreme weather and water. The takeaway for homeowners is simple: this is worth preparing for, not because of any single storm, but because the trend is going the wrong way.
How to prepare your property
The single best thing you can do is understand your own risk before the next storm, then put proportionate measures in place. In rough order:
Start with a survey. A property flood survey identifies how water is likely to reach your home and what will make the biggest difference, so you spend money where it counts rather than guessing. Our group's flood risk and engineering team at FPS Environmental carries out exactly this kind of assessment.
Consider Property Flood Resilience measures. These are the physical steps that keep water out or limit the damage when it gets in: flood barriers for doors and airbricks, non-return valves on drains, and resilient finishes lower down. Removable flood barriers are a common starting point.
Learn from the experts. We were recently on the BBC's Rip Off Britain talking about exactly this issue of surface water flooding and how households can protect themselves. You can read more in our piece on being featured on Rip Off Britain.
For transparency: FPS Environmental and Flood Protection Solutions are part of our group, alongside Flood & Water Pumps.
Where pumps come in: getting water out, and keeping it out
Barriers and resilience measures reduce how much water gets in, but surface water flooding is rarely fully kept out, especially below ground. That is where pumped drainage matters, and it is the part we know best.
For homes prone to water in a basement, cellar, lightwell or sunken room, a permanent pumped drainage setup is the reliable answer: a sump chamber collects any water that gets in, and a pump removes it automatically. For habitable basements this usually means twin pumps, a high-level alarm and battery backup so it keeps working in a power cut, which is exactly when heavy rain tends to strike. Our guides to sump pumps and cavity drainage explain how these systems work, and you can see suitable units in our sump pumps and basement waterproofing pumps ranges.
For clearing water during and after a flood, a puddle pump is the tool most people actually need. Puddle pumps are submersible pumps that remove water down to just 1 to 3 mm, where a standard submersible would leave 25 to 50 mm behind. They sit straight on the floor without a chamber, suit floods, basements, garages and patios, and come in manual and automatic versions. Browse our puddle pumps and wider drainage pumps for the right one. It is far better to have one ready in the cupboard than to be hunting for one as the water rises.
If you have been flooded this week
First, stay safe. Do not enter floodwater if you can avoid it, as the London Fire Brigade warned that as little as 30 cm of moving water can float a car, and floodwater can hide dangers and be contaminated. Keep clear of electrics until they have been checked. Once it is safe, photograph everything for your insurer before you start clearing up, then get the standing water out with a suitable pump and begin drying the property as soon as you can, because the longer water sits, the worse the damage.
Get prepared, or get help now
Whether you want to clear water today or protect your home before the next storm, we can point you to the right kit and the right advice. Browse puddle pumps and flood control, use the Pump Finder, or call the team on 0115 987 0358.
Frequently asked questions
What is surface water or flash flooding?
It is flooding caused by rain falling faster than the ground and drains can absorb it, rather than a river overflowing. The water ponds in low spots and runs off hard surfaces into basements, garages and ground floors. It can happen almost anywhere, often far from any river, and arrives quickly with little warning, as Richmond saw in both 2021 and 2026.
How can I protect my home from flash flooding?
Start with a property flood survey to understand your risk, then add proportionate measures: flood barriers for doors and airbricks, non-return valves on drains, and, for below-ground rooms, a pumped sump drainage system. Keeping a puddle pump on hand lets you clear water quickly if it does get in.
What pump do I need to clear flood water?
For clearing a flooded floor, a puddle pump is usually best, as it removes water down to 1 to 3 mm where a standard submersible leaves much more behind. For ongoing protection of a basement or cellar, a permanent automatic sump pump system is the answer, ideally with twin pumps, an alarm and battery backup.
Why does flash flooding seem to be getting worse?
Heavier, more sudden downpours are becoming more frequent as the climate warms, and older drainage networks are increasingly overwhelmed by them. That combination is behind the rise in surface water flooding events in places like Richmond, and it is why preparing now is sensible.
What should I do first if my house floods?
Stay safe: avoid entering floodwater, as even shallow moving water is dangerous, and keep away from electrics until checked. Once safe, photograph everything for your insurer, then pump out the standing water and start drying the property as quickly as possible to limit damage.
