Most of Batheaston is not, and the part that is sits exactly where anyone with a map would put it. The village climbs a hillside. The bottom of it does not. Two rivers meet down there, and rivers have opinions about channel capacity. Seven floods sit on the record. This is a place with a small, specific, well-understood wet edge rather than a general problem.
The Environment Agency's river-and-sea flood zones put roughly 3% of the area's postcodes in zone 3, the highest-probability band, and about 2% in zone 2. Those two are exclusive bands rather than nested ones: zone 2 is the additional medium-probability fringe sitting beyond zone 3, which is why it can be the smaller of the two figures without anything being wrong. Together they describe the valley floor, not the village as a whole.
Surface water is not mapped as its own share here. It is folded into the combined postcode indicators further down, which is worth knowing because surface water behaves differently from a river: it arrives off saturated ground and hard surfaces during heavy rain, and a house well above the Avon can still sit at the bottom of a slope. What the record does carry is that about 5% of postcodes fall inside historic flood outlines, across seven recorded events. The most recent was in October 2000, logged against a main river, with the cause given as channel capacity exceeded where no raised defences existed.
Looking forward, the climate-adjusted zone brings in about 1% of postcodes. That is a small figure, and the honest reading of a small figure is that it stays small. It is not a rounding error either, and it applies to the same low ground that already floods.
For insurance, the practical consequence is that this is an address-level question rather than a village-level one. A house on the higher ground will be quoted like any other house in Somerset. A house on the valley floor may attract loadings, a higher excess for flood specifically, or questions about previous claims. The gap between those two outcomes is a few hundred metres of ground level, which is why an indicative quote before instructing a solicitor is worth more than any general reassurance about the postcode.
Taking all the indicators together, including surface water, about 13% of the area's postcodes carry a high rating on at least one measure, roughly 10% carry a medium rating on at least one, and around 30% carry a low one. These bands overlap with the zone figures above rather than adding to them, because the same postcode can appear in both. The combined reading is deliberately broad, which is why it looks larger than the river-and-sea number.
Counted as homes rather than postcodes, the Environment Agency's rivers-and-sea mapping lists 376 properties across the 21 postcodes that carry any risk at all. Within those, 27 properties sit at high risk, 21 at medium, 80 at low and one at very low. Of the high-risk properties, 7 are residential. Everything outside those 21 postcodes does not appear in the mapping at all, which is the more relevant fact for most buyers here.
On whether anything stands between the water and the house, the modelled extents put about 3% of postcodes inside the high-risk extent undefended and about 3% inside it defended, with roughly 5% inside the low-risk undefended extent. Defended is a modelling term meaning a defence is present in the model. It is not a statement that the property is safe, and it should never be read as one. The October 2000 event was recorded on a stretch with no raised defences at all.
The nearest tide gauge in the long record is at Portsmouth, where measurements from 1962 to 2023 show a historic rise of about 2 millimetres a year. That is a measured coastal rate rather than a forecast, and it matters here only as background to how river systems behave over decades, not as a description of the Avon at Batheaston.
Flood risk in Batheaston lands in the middle: a real, mapped, small area of genuine exposure at the bottom of the valley, and the rest of the village barely touched. Which of the two you are buying is a question about one specific address, and it has a definite answer.