Mostly no, and where the answer turns to yes it turns very specifically yes. The bulk of the town sits above the water on Mendip slopes. A thin strip along the valley bottom does not. Blocked drainage has caused more grief here than the brook ever managed on its own. This is a dry town with a wet seam running through it, and the only question that matters is which side of that seam your house is on.
Under the Environment Agency's river and sea mapping, about 2% of the town's postcodes fall inside flood zone 3, the highest-probability band, and about 8% fall inside zone 2. Those are separate bands rather than nested ones. Zone 2 is the wider medium-probability fringe that sits beyond zone 3, which is why it covers more ground while carrying less risk. Together they describe the Wellow Brook corridor and very little else, because the rest of Radstock was built on the hillsides where the coal was.
Drainage is the more honest local hazard. The Environment Agency's historic record lists 58 flood events for this area, and about 10% of postcodes sit inside the mapped extent of past flooding. The most recent recorded event was in November 2012, and the cause was an obstructed culvert on a main river. Water that has nowhere to go finds somewhere to go, and in a town stitched together from Victorian industrial infrastructure it usually finds it through somebody's garden.
Add the climate allowance and the footprint widens. About 15% of postcodes fall within the zones once the Environment Agency models future sea level and rainfall into them, against the 8% and 2% for zones 2 and 3 today. That is the number a buyer planning to still be here in thirty years should be looking at, not the current one.
For insurance, the practical effect is binary rather than gradual. A property outside the mapped zones will be quoted as ordinary risk and nobody will mention flooding at all. A property inside them may attract a higher excess, a specialist underwriter, or a request for a flood report before cover is confirmed. Getting an indicative quote before instructing a solicitor costs nothing and settles the question in an afternoon.
Widen the lens to every flood indicator, surface water included, and about 12% of postcodes rate high on at least one measure, about 12% rate medium, and about 36% rate low. Those bands overlap with the river-and-sea zones rather than sitting alongside them, so they are a different way of counting the same town and not an additional layer of risk to be stacked on top.
Counted as homes rather than postcodes, the Environment Agency's rivers and sea mapping puts 503 properties in the frame across the 32 postcodes that carry any risk at all. Of those, 18 are at high risk, 42 at medium and 171 at low. Only 8 of the high-risk properties are residential. That is a short list in a town of this size, and it is a list, which means the address either appears on it or does not.
Defences make no difference to the worst of it. The modelled high-risk extent covers about 2% of postcodes undefended and about 2% defended, which is the same share twice. A defence being present in the model is not the same as a defence protecting the house, and in this case the model does not show it shrinking the high-risk footprint by anything worth mentioning.
Sea level is close to irrelevant here and worth stating anyway, because the nearest tide gauge to this landlocked former coalfield is at Portsmouth. Over its record from 1962 to 2023 it has measured a rise of about 2 millimetres a year. That is history rather than forecast, and the sea is not the thing that will ever come for Radstock.
The flood picture is middling, which is the correct answer for a town where most streets will never see water and a small number of addresses in the valley absolutely will. Put the exact address into the Environment Agency's long-term flood-risk service before you get attached to the kitchen.