Mostly no, with a short list of exceptions. About one postcode in a hundred falls inside the highest river flood zone. The larger part of the risk comes from surface water, the kind that arrives off tarmac and roofs rather than out of a channel. Six properties are rated high risk from rivers and the sea. Crewkerne is not a flood town. It is a town with a flood list, and the only question that matters is whether an address is on it.
On the Environment Agency's river and sea flood zones, about 1% of the town's postcodes sit in zone 3, the highest probability band, and about another 1% in zone 2, the medium probability fringe that lies beyond zone 3 rather than wrapping around it. They are separate bands, not one inside the other, so adding them into a single alarming total misreads the map. People do it constantly.
Surface water is where the shape changes. It runs off hard ground after heavy rain, ignores the river map entirely, and explains why a town on the headwater of the River Parrett can have a small river footprint and a much wider flagged one. Four flood events have been formally recorded here, the most recent in 2008, logged against the main river and caused by a blocked culvert. About 1% of postcodes fall inside a recorded historic flood outline. A blockage is a maintenance question rather than a geographical one, which is either reassuring or not, depending on how much faith anyone has in drain clearing.
Apply the Environment Agency's climate allowance and the share of postcodes inside a flood zone reaches about 5%. That is the forward-looking version of the same mapping rather than a forecast for any particular winter, and it is the figure that matters for a house somebody intends to own for the next thirty years.
For insurance, cover is priced by address and not by town. The great majority of Crewkerne will get ordinary quotes without anybody blinking. Homes inside the mapped extents can expect questions about previous claims and an excess set accordingly. An indicative quote before exchange, rather than after, is the fastest honest answer available on any specific house, and it costs nothing but a phone call.
Across the 217 postcodes assessed on the postcode-level indicators, about 8% carry a high rating on at least one flood measure, about 10% a medium rating and about 24% a low one. That set folds surface water in alongside rivers and sea, so it overlaps the zone figures rather than adding to them. Stack the two together and you invent a town that does not exist.
Counted as homes rather than postcodes, the Environment Agency's rivers and sea mapping lists 287 properties across the 14 postcodes that carry any risk at all. Of those, 6 are rated high risk, 4 of them residential, with 12 at medium risk and 50 at low. Postcodes with no risk do not appear on that list at all, which is most of the town.
On defences, about 1% of postcodes sit inside the high probability extent with defences present in the model, and about 1% with them stripped out. The two versions agree, which means defences are not doing much lifting here one way or the other. Defended is a modelling term describing what exists on the ground nearby. It has never been a statement that a particular house is protected, whatever a listing might imply.
Sea level comes up in every flood conversation, so for completeness: the nearest tide gauge, at Devonport, measured an average rise of about 2.35 millimetres a year across its record from 1962 to 2015. That is a measured historic rate at a coastal gauge some way off, and this is a town on a river headwater. It sets the backdrop rather than the water that turns up at the door.
Middling, then, and specifically middling. The town as a whole is fine, a small number of addresses genuinely are not, and no amount of reading about Crewkerne substitutes for checking the exact one.