Goffs Oak has no rivers to worry about and enough rain to take seriously. No postcode is in a river or sea flood zone. Nothing on record has flooded. About one postcode in seven still rates high on some measure, and the cause is rainwater. In Goffs Oak the water comes down rather than across.
On the Environment Agency's river-and-sea mapping, none of Goffs Oak's postcodes fall in flood zone 3, the highest-probability band, and none fall in flood zone 2, the medium-probability fringe beyond it. Both shares are 0%. The village is on high ground north of the M25, and no river comes near enough to reach the flood zones.
That leaves surface water. With both river-and-sea zones empty, the flags that do appear on the postcode measures below come from the other indicators, chiefly heavy rain that runs off faster than the ground and the drains can take it. That kind of flooding comes and goes in an afternoon, and it can affect one house on a road and miss its neighbour.
The Environment Agency's climate-adjusted zone, which allows for heavier rain and higher rivers in future, also puts 0% of Goffs Oak's postcodes inside it. The rivers are still not expected to reach the village, even allowing for that.
For insurance, a clean river-and-sea record should help, but insurers price surface water as well, and a postcode that flags high for it can get a dearer or more cautious quote than the zone map would lead you to expect. The Environment Agency's long-term flood risk service shows surface water separately for each address, and it is worth putting the exact address in there and getting an indicative insurance quote at the same time.
Counting postcodes that rate high, medium or low on at least one of several flood measures, surface water included, about 14% of Goffs Oak's postcodes rate high, 11% medium and 39% low. Each postcode counts once, at the worst rating any of its measures gives it. That is a different measure from the empty river-and-sea zones above, and both are accurate.
On the Environment Agency's modelled high-risk flood extents, 0% of Goffs Oak's postcodes are inside an undefended extent and 0% inside a defended one. No defence appears in the model because no modelled river flood reaches the village. That says nothing about rain on a blocked drain.
The nearest tide gauge in the record is at Portsmouth, which measured sea level rising by about 2 millimetres a year between 1962 and 2023. That rate applies to Portsmouth harbour over those years. Goffs Oak is a long way inland, which is about all the gauge has to say about it.
The record holds no historic flooding anywhere in Goffs Oak, with 0% of the area inside a recorded flood outline. That is reassuring. A recorded outline only exists for a flood that someone mapped, though, and a summer storm that filled one garden would not have made it onto the map.
Flood risk in Goffs Oak is middling. The rivers and the sea are no threat, and the surface-water flags on a minority of postcodes are why it is still worth checking each address.