Bordon has almost no river or sea flood risk, and the thing to check is rain. No postcodes fall in the highest river-and-sea zone. The one recorded flood is decades old. About one postcode in eleven still rates high on some flood measure. That high rating comes from somewhere other than the river, and it's where a buyer should look.
On the Environment Agency's river-and-sea flood zones, none of Bordon's postcodes fall in Flood Zone 3, the highest-probability band. Fewer than 1% fall in Flood Zone 2, the medium-probability band that sits beyond Zone 3. The two zones don't overlap, so a smaller Zone 2 share doesn't contain the Zone 3 share. Only one flood event is on record, from 1968, when a main river overflowed its channel with no raised defences in the way.
Surface water is a different kind of flood and it doesn't show up in those zones. It happens when heavy rain arrives faster than the ground and the drains can take it, and it can reach streets nowhere near a river. The brief doesn't carry a separate surface-water-only figure for Bordon, so it appears only as part of the postcode ratings below. Where a postcode rates high on some measure but sits outside the river-and-sea zones, surface water is the first thing to ask the seller and the surveyor about.
The Environment Agency also maps a climate-adjusted zone that shows where river-and-sea flooding could reach with a warmer climate. About 1% of Bordon's postcodes fall inside it. That is a small share, and it's the forward-looking figure to hold against the present-day one.
For insurance, river-and-sea risk this low rarely troubles standard home cover. A postcode with a surface-water rating can still affect quotes or excesses, and insurers assess the individual address, not the town. An indicative quote before exchange tells you more than any area average.
Across all flood measures together, including surface water alongside rivers and the sea, about 9% of Bordon's postcodes rate high on at least one of them, about 12% rate medium and about 29% rate low. Because these ratings count any single measure, they overlap with the zone figures above and shouldn't be added to them. They are the wider net, and they explain why a town with almost no river risk still has homes that need a closer look.
The Environment Agency's modelled flood extents put none of Bordon's postcodes in a high-risk extent, either with or without defences. So the question of whether a defence stands between the water and the house doesn't arise for river and sea flooding here. Where a model does show a defence, that only means one is present in the model. It is never a guarantee that the house stays dry.
The nearest tide gauge, at Portsmouth, recorded sea level rising by about 2 millimetres a year over its record from 1962 to 2023. That is a measured past rate, not a forecast. Bordon is inland, in the forest, and the sea is not its problem.
Before you buy:
- Put the exact address into the Environment Agency's long-term flood risk service and check the surface-water result, not just rivers and sea.
- Ask the seller in writing whether the property has ever flooded or had a flood-related insurance claim.
- Get an indicative insurance quote before instructing a solicitor.
- Ask your surveyor to look at drainage and ground levels around the house.
Flood risk in Bordon is middling rather than alarming: rivers and the sea barely register, but surface water puts a minority of postcodes on the list for a proper check.