Yes, and a buyer here needs to check it for the specific address. About a quarter of postcodes sit in the highest river-and-sea flood zone. None of that high-risk area has a defence in the model. Once climate change is factored in, almost the whole town is inside the flood zone. Most homes stay dry most years, but the ground they're built on is low, and pretending otherwise is how buyers get caught out.
For river and sea flooding, the Environment Agency's flood zones place about 25% of the area's postcodes in Zone 3, the highest-probability band, and another 14% in Zone 2, the medium-probability fringe beyond it. The bands don't overlap: Zone 2 is the extra ground around Zone 3, not a bigger area containing it. The town sits on land reclaimed from the river and the sea, the monks' wall of the 13th century still marks one edge of it, and the 1953 floods covered the whole area around Sandwich. The Environment Agency lists five recorded flood events, the most recent in 1983, when the main river overtopped its channel with no raised defences in place.
Surface water is a separate problem and harder to spot at a viewing, because it comes from rain that can't drain away, not from the Stour. Flat, drained land like this relies on ditches and pumping to move water, and about 3% of postcodes fall within the River Stour (Kent) Internal Drainage Board's district. There's no standalone surface-water share for the area. It's folded into the combined postcode measure further down, which is the right place to look for it.
Looking ahead, about 93% of postcodes fall inside the Environment Agency's climate-adjusted flood zone, which models how the zones grow as conditions change. That isn't a forecast of flooding. It shows how much of Sandwich sits only a little above the line, and why a house that's fine on today's map can look different on the next one.
For insurance, this is a town where you get the quote before you instruct the solicitor, not after. Properties in the higher zones can face higher premiums, excesses on flood claims, or insurers who decline, and a seller calling it "never been an issue" is not a substitute for a quote in writing.
The combined postcode picture folds surface water in alongside rivers and sea. About 17% of postcodes rate high on at least one flood measure, 30% medium and 57% low. Each postcode counts in a band if any single measure puts it there, so these shares overlap with the flood-zone figures and must not be added to them. They answer a different question: how many postcodes have some flood risk to think about from any direction.
Counted by building, the Environment Agency's rivers-and-sea mapping lists 1,852 properties in the postcodes that carry some risk: 59 at high risk, 257 at medium, 785 at low and 333 at very low. Of the high-risk properties, 46 are homes. Only postcodes with some risk appear in that count at all, so it describes the exposed part of town, not the whole of it. Fifty-nine buildings is a small number, but that's no comfort if you're buying one of them.
On defences, about 25% of postcodes fall inside the high-risk extent with no defence present in the model, and 0% sit inside a defended high-risk extent. "Defended" would only mean a defence appears in the model, never that a house is safe. Here, the model doesn't record even that.
On the coast, the shoreline management plan's most common policy for the stretch nearest Sandwich is no active intervention over 20, 50 and 100 years. That's a stated intention not to build or maintain defences on that frontage, not a promise and not a structure. The town sits about 3,000 metres from the coast on the median postcode, and none of it lies within 500 metres, so the policy affects the coastline more than the old town's front doors.
The Dover tide gauge recorded sea level rising at about 2 millimetres a year between 1961 and 2010. That's a measured historic rate over that record, not a prediction, and it's slow enough that nobody notices it until they look at the flood zones.
Flood is Sandwich's weak point, and it deserves proper checks before anyone signs. Buyers on the higher ground can mostly move on, and buyers near the river should treat the flood map as seriously as the survey.