Yes, and enough that it should shape which house a buyer picks. More than a third of postcodes carry a high flood risk on at least one measure. About one in ten are in the highest river-and-sea flood zone. Allowing for a wetter climate, that zone grows to cover about a third. A pretty valley floor is pretty because water made it.
On the Environment Agency's river-and-sea mapping, about 10% of Lower Nazeing's postcodes are in Flood Zone 3, the high-probability band. Another 19% are in Flood Zone 2, the medium-probability fringe beyond it. The two bands don't overlap, so the larger number is the outer ring, and it doesn't contain the smaller one. Together they put a fair stretch of the village on the river's side of the line.
Surface water isn't reported as a separate figure for the village. It is counted in the postcode measure further down, alongside rivers and sea, and it is the kind of flooding that ignores which side of a flood-zone boundary a house is on.
The Environment Agency also models the flood zones with an allowance for climate change, and on that basis about 33% of postcodes fall inside. That is modelled for a wetter future, and a buyer on a 25-year mortgage will be living in it.
Insurers read the same maps, and a postcode inside a flood zone can mean higher premiums, a larger excess, or fewer firms willing to quote at all. Getting a buildings-insurance quote for the exact address early, while a buyer can still walk away cheaply, does more than any amount of reading. A house in the high-risk band that turns out to be expensive or awkward to insure is also harder to sell on.
A wider measure counts a postcode if it is at risk on any one of several indicators, surface water included. On that test about 37% of postcodes in the area are at high risk on at least one measure, 38% at medium risk and 62% at low risk. Because a single postcode can be caught by more than one indicator, these shares overlap, and they don't add up to a total.
Counting homes gives a sharper picture than counting postcodes. The Environment Agency's rivers-and-sea mapping lists 33 postcodes with some risk, covering 1,020 properties. Of those, 204 are at high risk, 66 at medium, 171 at low and 47 at very low. About 99 of the high-risk properties are homes. Postcodes with no risk at all aren't in that list, so the 1,020 is the exposed part of the village, and the rest of it isn't included.
Then there's the question of whether anything stands between the river and the houses. In the Environment Agency's modelled flood extents, about 10% of postcodes are in the high-risk extent without defences, and the share is the same, about 10%, with defences included. Wherever defences appear in the model, they don't shrink the high-risk footprint here. "Defended" on a sales sheet would be describing something the mapping can't find.
Flood risk is Lower Nazeing's weakest point, by a distance. Buyers can still choose well within the village, but no buyer should assume the house they like is on the dry side.