Mostly no, and the risk that does exist falls out of the sky rather than up from a river. None of the town sits in the river-and-sea flood zones. The coast is several miles off. What catches people here is rainwater with nowhere convenient to go. That is a drainage question, not a river question, and it does not spread itself evenly across the town.
Start with the formal picture. The Environment Agency's river-and-sea flood zones cover 0% of Ferndown's postcodes in zone 3, the higher-probability band, and 0% in zone 2, which is the additional medium-probability fringe sitting outside zone 3 rather than wrapped around it. Both are empty. For a town built on gravel terraces on the north bank of the River Stour, that is a better result than the geography suggests, and it is the single most useful line in this whole answer for anyone whose solicitor is about to order a search.
Surface water is where the actual exposure lives. With the river-and-sea zones reading zero, everything showing up on the flood indicators here is rain landing faster than the ground and the drains can take it, plus groundwater underneath. Surface-water flooding is the sort that arrives in an afternoon, ruins a downstairs floor, and never appears on a map anyone thought to check.
Looking forward, the Environment Agency's climate-adjusted zone extent also covers 0% of the town's postcodes. The projection does not pull Ferndown into the river floodplain.
For insurance, this is close to the easiest conversation a buyer in Dorset can have. A property outside the river-and-sea zones is not the kind of address that triggers a specialist underwriter or a loaded excess. That said, surface-water risk sits at postcode level rather than address level, so the sensible move is still an indicative quote on the specific property before anyone instructs a solicitor, not after.
At postcode level, across the 431 postcodes with flood indicator coverage, about 10% rate high on at least one measure, roughly 14% rate medium and around 28% rate low. Those bands fold surface water in alongside rivers and sea, they overlap with each other, and they measure something different from the zone figures above. They are not additive, and anyone presenting the 10% as "a tenth of Ferndown is in a flood zone" has misread the label.
Counted as homes rather than postcodes, the numbers shrink dramatically. The Environment Agency's rivers-and-sea mapping lists just 2 postcodes in Ferndown carrying any risk at all, holding 59 properties between them. Of those, 1 property is at high risk, 2 at medium and 2 at low, and none of the high-risk properties is residential. Only postcodes carrying some risk appear in that dataset at all, so the silence from everywhere else is the point.
On defences, 0% of the town's 437 postcodes fall inside a modelled high-risk flood extent, defended or undefended. There is nothing here for a defence to stand in front of. Worth remembering in general: "defended" in these models means a defence exists in the model, not that the house behind it is safe, and plenty of buyers elsewhere have read it the wrong way round.
The shoreline management picture matters less here than it would nearer the water. About 55% of the town's postcodes fall inside a shoreline management plan area, and the stated policy over the twenty, fifty and hundred year horizons is hold the line. That is an intention to maintain coastal defences, not a promise, and not a defence that necessarily exists yet. Ferndown's nearest point to the coast is roughly 8 kilometres away, with the median postcode around 9 kilometres out, so the policy is a distant concern rather than a doorstep one. At the nearest tide gauge, Portsmouth, sea level rose at about 2 millimetres a year across the 1962 to 2023 record. That is a measured historic rate, not a forecast.
There is no recorded historic flooding across the area at all, which is genuinely reassuring and is also not the same as proof that nothing has ever happened. Records only capture what someone logged.
Flood risk here is middling rather than clean: the rivers and the sea are a non-event, and the surface-water indicators are real enough that the specific address matters more than the town name.