Yes, in places, and the places are what matter. About one postcode in five here carries a high flag on at least one flood measure. The formal river-and-sea zones cover a far smaller slice of the town. Nothing in the area sits inside a recorded historic flood outline. Three sentences, three different answers, which is exactly why the question has to be asked about an address rather than about a town.
Start with the narrowest measure. The Environment Agency's river-and-sea flood zones cover about 3% of the area's postcodes in zone 3, the higher-probability band, and about 1% in zone 2. Those two are exclusive bands rather than nested ones: zone 2 is the additional medium-probability fringe sitting outside zone 3, which is why it can legitimately be the smaller of the pair. On rivers and sea alone, then, the overwhelming majority of Mere is outside the mapped zones entirely.
Surface water is a different animal and does not get its own headline number here. It is folded into the combined postcode indicators alongside rivers and sea, which is worth knowing because in a town sitting below the downs, the water that reaches a doorstep often arrives across a road rather than out of a channel. The combined measure is the one that produces the uncomfortable figure, and it is uncomfortable precisely because it counts the water that no river map will ever show you.
Looking forward, the Environment Agency's climate-adjusted extent lifts the zone coverage to about 5% of postcodes. That is a modelled allowance for a wetter future rather than a prediction of a specific event, and it roughly doubles the footprint of the mapped zone. A house on the edge of the current zone is the one to think hardest about, because the edge is where the allowance bites.
For insurance, the practical consequence is straightforward. A property inside the mapped zones or flagged on the surface-water indicators can be harder to cover and more expensive to cover, and the difference shows up as a premium and an excess rather than a refusal. Get an indicative quote on the specific address before instructing a solicitor, not after. An insurer's underwriting will tell you more about a house than any area-level percentage on any website, including this one.
The combined postcode picture is the one that drags the town's flood standing down. About 19% of postcodes rate high on at least one measure, about 15% medium, and about 26% low. Those bands fold surface water in alongside rivers and sea, so they overlap with the zone figures rather than adding to them. Roughly one in five postcodes carrying a high flag on something is not a rounding error in a town of this size.
Counting homes rather than postcodes sharpens it further. The Environment Agency's rivers-and-sea mapping lists 120 properties across the postcodes that carry any risk at all, of which 28 are at high risk, 6 at medium and 20 at low. Only postcodes with some measured risk appear in that list, so this is a picture of the exposed streets rather than of the town.
On defences, the answer is blunt. About 3% of postcodes fall inside the modelled high extent whether or not the model counts defences as present, which means nothing meaningful is standing between the water and those homes in the modelling. About 4% sit in the low undefended extent. A defence appearing in a model has never kept anyone dry on its own, and here there is barely a defence to argue about.
The nearest tide gauge is at Portsmouth, where the recorded rate of sea level change runs at about 2 millimetres a year across a record from 1962 to 2023. For an inland market town that is context rather than threat, and it belongs in the file marked background.
There is no recorded historic flooding across the area, which is genuinely reassuring and is not the same as proof it has never happened. Records begin when someone starts keeping them.
Flooding is the softest spot in Mere's risk profile. The zones are small, the surface-water flags are not, and the honest position is that a fifth of the town's postcodes carry something worth a conveyancer's attention.