Buckhurst Hill is safe from the river and much less safe from the rain. Almost none of the town is in the river-and-sea flood zones. Once surface water is counted, nearly a quarter of postcodes rate high on at least one flood measure. Not a single home is rated high for river flooding. The town is named after a hill, and the hill keeps the Roding at a distance while doing nothing about what falls on it.
On the Environment Agency's river-and-sea flood zones, about 1% of the area's postcodes are in zone 2, the medium-probability band, and none at all are in zone 3, the highest. Zone 2 only covers the fringe outside zone 3, and here there is no zone 3 for it to surround. The Environment Agency has four floods on record, the latest in December 2000, when a main river overflowed a channel with no raised defences. Until 1890 there was no bridge to Chigwell and residents had to ford the Roding, which was the closest most of the town ever got to the river.
Surface water is the bigger worry, and the river zones leave it out entirely. Rain that cannot drain away does not wait for a river to rise, and on a hillside it runs downhill to wherever the gardens and driveways happen to be lowest.
Looking ahead, the Environment Agency's climate-adjusted flood zone covers about 1% of postcodes, unchanged from today's zone 2. On its own modelling, a warmer climate does not push the rivers much further into town.
Insurers price each address on its own flood indicators, so a house on one of the higher-rated postcodes can attract a different premium from its neighbour further up the slope. Ask for a buildings insurance quote on the exact address while the survey is being done, so the answer arrives in time to affect the offer.
Counted by postcode, where any one of several measures is enough to qualify, surface water included alongside rivers and sea, 23% of the area's postcodes rate high on at least one, 19% medium and 42% low. That is the figure the flood zones never show, and it is the one that matters on a hill.
Counting homes gives a smaller and more useful picture. The Environment Agency's rivers-and-sea mapping lists only 3 postcodes with any risk at all, covering 133 properties. Of those, 5 are rated high, none medium, 16 low and 7 very low. None of the 5 high-rated properties is a home.
Defences barely come into it. In the Environment Agency's modelled flood extents, no postcode falls in the high-risk area either with or without defences, and only a fraction of 1% is in the low-risk extent without them. Here "defended" would only mean a defence appears in the model, and the model has almost nothing for one to defend.
Flood risk is a weak spot for Buckhurst Hill. The river leaves the town alone, but the rain does not, and a buyer needs to look at each street on its own.