Mostly not, but the Thames has been over its banks here before. None of the area sits in the river-and-sea flood zones. A handful of properties still register at high risk. The river last came out of its channel within living memory. The overall figures look reassuring, and the individual address is what you need to check.
On the Environment Agency's river-and-sea flood zones, 0% of Greenlands' postcodes fall in zone 3, the highest-probability band, and 0% fall in zone 2, the medium-probability band beyond it. The two zones don't overlap, so neither contains the other, and here both are empty. For a place this close to the Thames, that is a better result than many buyers expect.
The brief carries no standalone surface-water figure for Greenlands. Surface water is included in the postcode-level indicators further down, and it is the reason those indicators differ from the zone figures. Rain that can't drain doesn't care what flood zone the map says you're in.
Looking ahead, the Environment Agency's climate-adjusted flood zone also covers 0% of postcodes. On that modelling, the river-and-sea picture doesn't worsen under the allowance it uses for a warmer, wetter future.
For insurance, a postcode clear of the flood zones usually makes cover easier to arrange, but insurers price the address, not the area average. A recorded flood nearby or a property flagged at risk in the Environment Agency's own mapping can still affect the quote, so get an actual figure for the house you want before you rely on the zone result.
The postcode-level picture folds surface water in with rivers and sea, so it measures something different from the zones above and shouldn't be added to them. Of the seven postcodes, 0% rate high on at least one measure, about 14% rate medium on at least one measure and about 43% rate low on at least one measure. The same indicators record historic flooding at about 14% of postcodes. The Environment Agency holds 2 recorded flood events for the area, the latest in January 2003, when the main river exceeded its channel capacity where no raised defences stood.
Counting properties rather than postcodes gives a sharper result. The Environment Agency's rivers-and-sea mapping lists 2 postcodes that carry some risk, containing 22 properties between them. Of those, 2 properties are at high risk, 1 at medium and 1 at low, and none of the high-risk properties is a home. Postcodes with no risk at all don't appear in this count, so it describes where the risk sits rather than the whole of Greenlands. It is also a different measure from the zone share, which is why a place can have no postcodes in zone 3 and still have two properties flagged at high risk.
On defences, 0% of postcodes sit inside the modelled high-risk extent without defences, and 0% inside it with defences. Nothing appears in either column, so the model shows no high-risk extent here that defences are protecting. The 2003 flood happened where there were no raised defences, and the model has no view on what a surveyor would find on the riverbank itself.
The nearest tide gauge, at Portsmouth, recorded sea level rising by about 2 millimetres a year across its record from 1962 to 2023. That is a measured historic rate at a coastal gauge a long way from Greenlands, not a forecast for the Thames at Henley.
Before you commit to a house here:
- Put the exact address into the Environment Agency's long-term flood-risk service, not just the postcode.
- Ask the seller directly whether the property was affected in 2003 or has ever made a flood claim.
- Get an indicative buildings-insurance quote before instructing a solicitor.
- Ask your surveyor to look at drainage and any low-lying ground towards the river.
The flood risk in Greenlands is middling. The zones are clear, but a riverside history and a few flagged properties mean you need to check the address, not rely on the area figures.