Not from rivers or the sea. None of Four Marks sits in a river or sea flood zone. That doesn't change when the climate allowance is added. The only realistic source is rain with nowhere to go. Surface water is the risk here, and it's a small one.
On the Environment Agency's river-and-sea mapping, 0% of the area's postcodes fall in flood zone 3, the highest-probability band, and 0% fall in flood zone 2, the medium-probability fringe beyond it. Both are zero. A village on a ridge between two river systems has no river running through it to break its banks.
That leaves surface water, which ignores flood zones completely. A heavy downpour on paved drives and a road that can't drain fast enough can put water where no river map ever would. It's the kind of flooding that happens on a street rather than across a valley, and a buyer should check it at the level of the individual address.
The Environment Agency's climate-adjusted zone, which projects the river-and-sea picture forward, also covers 0% of postcodes. On that measure, the future looks the same as the present.
Insurance should be straightforward for most homes here, because river and sea flood zones are what insurers look at first, and Four Marks has none. A property sitting in a surface-water low spot can still attract a question or two, so get a quote on the specific address before you commit rather than assume the village figure applies to every house.
The postcode-level measure, which counts a postcode if it rates high, medium or low on at least one flood indicator including surface water, puts about 2% of postcodes at high risk, 5% at medium and 13% at low. These bands overlap with the zone figures above and measure something different, so don't add them together. They're the reason a clean flood-zone map isn't the end of the conversation.
On the modelled flood extents, 0% of postcodes sit in a high-risk area with defences, and 0% without them. So the question of whether anything stands between the water and the house doesn't come up. There's no modelled high-risk extent to defend. Even where defences do appear in these models, that means only that a defence exists, not that the house behind it is safe.
The nearest tide gauge is Portsmouth, where the record from 1962 to 2023 shows sea level rising at about 2 millimetres a year. That's a measured historical rate at the coast, not a forecast, and not a direct threat to a village this far inland.
There's no recorded historic flooding in the area. That's genuinely reassuring. But it only tells you nothing has been recorded, not that no garden has ever had water in it.
Before buying, it's worth doing the following:
- Put the exact address into the Environment Agency's long-term flood risk service and read the surface-water result, not just the river one.
- Ask the seller directly whether the property has ever had water inside or on the drive.
- Get an indicative insurance quote before instructing a solicitor.
- Look at where the road drains during a heavy shower, if the viewing timetable allows.
Flood risk is one of the lesser worries for a Four Marks buyer: no river or sea exposure, now or with the climate allowance, and a surface-water risk confined to a few postcodes. Check the address, then move on to the other questions.