Ealing has a flood problem, but it comes from rain, and the River Brent has little to do with it. Rivers and the sea reach almost nowhere. Heavy rain reaches about one postcode in six at the highest level. The postcodes with no reading on any measure are a minority. The official flood zones make Ealing look dry, and they are only measuring the rivers and the sea.
The Environment Agency's river-and-sea flood zones cover well under 1% of Ealing's postcodes, and that is true of zone 3, the highest-probability band, and of zone 2, the medium-probability fringe beyond it. The agency's records hold a single recorded flood, from a main river in December 1977, when the channel overflowed in a place with no raised defences. The River Brent runs through Pitshanger Park, and the rest of the time it keeps to its banks.
Surface water is a different matter. It happens when heavy rain cannot drain fast enough and collects in roads, gardens, basements and low thresholds, wherever the ground and the drains send it. On a district built up as densely as Ealing, that is the flood risk that counts, and the river-and-sea zones do not include it at all.
The Environment Agency's climate-change version of the river-and-sea zones still puts well under 1% of postcodes inside them. On that measure, a warmer climate barely changes Ealing's river picture.
For insurance, the gap between the two measures is the point to watch. Insurers price individual addresses using surface-water mapping as well as the river zones, so a house in Ealing that is nowhere near a flood zone can still be quoted as a flood risk. Get an indicative buildings-insurance quote on the exact address early, and if the premium comes back higher than expected, that is where the surface-water mapping shows up.
Taking every measure together, including surface water as well as rivers and the sea, about 16% of Ealing's postcodes rate high on at least one of them, about 19% medium and about 43% low. A postcode only needs one of several measures to register for it to count, which is why these shares are so much bigger than the river zones. In Ealing, those numbers come from the drains and the rain.
Counted by property, the Environment Agency's rivers-and-sea mapping lists 292 properties across the only postcodes in Ealing that carry any river or sea risk. Of those, 8 are at high risk, 65 at medium, 17 at low and 1 at very low. A count that small for a district this size shows how little the rivers matter here.
The Environment Agency models the high-risk river extent with and without defences, and in Ealing both versions cover the same small share of postcodes, well under 1%. "Defended" only means a defence appears in the model. It says nothing about whether water would reach a particular front door, and here the defences make no visible difference to the map.
The nearest tide gauge in the records is at Portsmouth, where the measured rise in sea level was about 2 millimetres a year between 1962 and 2023. Ealing is less than two miles from the tidal Thames at Kew Bridge, but on the agency's maps the tide is somebody else's problem.
The rivers are a small risk in Ealing and the rain is the bigger one, so the flood picture is weaker than the official zones suggest, and the district rates below average for flood risk.