A small part of it is, mostly close to the water. Very little of the area is in the river flood zones. About one postcode in nine rates high on at least one flood measure. The most recent recorded flood came from a stream, not the river. Most homes here are not at risk, but whether a particular house is depends on exactly where it sits.
On the Environment Agency's river-and-sea mapping, about 2% of the Brockham area's postcodes are in flood zone 2 and under 1% are in flood zone 3. The two zones don't overlap. Zone 3 is the higher-probability land nearest the water, and zone 2 is the medium-probability fringe beyond it, so a smaller zone 2 figure is normal here. For a village with the River Mole running through it, that's a small footprint. The river is a real risk, but only for the homes nearest to it.
Surface water is where the more common risk shows up, and the flood record reflects it. Nine flood events are recorded for the area. The latest was in January 2014, when an ordinary watercourse overflowed its channel where there were no raised defences. About 3% of the area falls inside recorded historic flood outlines. That was a smaller watercourse than the Mole, and ditches and brooks like it are easy to miss when you're viewing a house.
Allowing for climate change, the Environment Agency's climate-adjusted flood zone covers about 5% of the area. That's larger than today's zones, but it describes the same low ground by the water, not a new stretch of the village.
For insurance, the risk sits at the level of individual houses, not the whole village. Most addresses here should get ordinary quotes. A house on low ground near the river or a stream may find premiums, excesses or terms change once the insurer checks the exact location. Get a quote for the specific address before committing to a purchase.
Taken postcode by postcode, about 11% of postcodes rate high on at least one flood measure, about 9% medium and about 22% low. These figures combine surface water with river and sea risk, and they overlap with the zone figures above, so the two sets can't be added together. They measure different things and should be read separately.
Counting homes is more useful than counting postcodes. The Environment Agency's river-and-sea mapping lists only 10 postcodes that carry any risk, with 199 properties between them. Of those, 16 properties are at high risk, 3 at medium, 16 at low and 1 at very low, and 10 of the high-risk properties are homes. Every postcode outside those 10 carries no river-and-sea risk at all on this measure.
On flood defences, under 1% of postcodes sit in the modelled high-probability extent with no defence, and none sit in a defended one. There's no defence in the model protecting the high-risk land here. Even where a defence does appear in the model, that only means one exists, not that the house behind it is safe.
The nearest tide gauge is at Portsmouth, where the record from 1962 to 2023 shows sea level rising by about 2 millimetres a year. That's a measured historic rate, not a forecast, and for an inland village on a river it matters far less than the local brooks.
Brockham's flood risk is middling: low for most homes, and real for the few near the water. It comes down to the individual house, so check the exact address before you buy.