For most homes in the Pulborough area the risk is low, and the exceptions are specific ones. Only a sliver of postcodes fall inside the river and sea flood zones. Once rain running off the land is counted, about one in eight postcodes shows high risk on at least one measure. The coast is several miles off. What matters here is the exact address, not the postcode.
In the Environment Agency's river-and-sea flood zones, about 1% of the area's postcodes sit in flood zone 3, the highest-probability band, and a further 1% fall in flood zone 2, the medium-probability fringe beyond it. The two bands don't overlap. Together they cover a small part of the area, much of it along the valley floor of the Arun and its tributaries.
The river zones leave out surface water entirely, and that is the risk these zones don't show. Heavy rain that can't soak away or drain fast enough collects in low roads, dips and gardens, whether or not a river is nearby. Surface water is counted in the postcode-level figures further down this page, which is why those figures come out higher than the zone shares.
The Environment Agency also publishes a flood zone with a climate change allowance, and about 2% of postcodes fall inside it. That is the modelled future extent, and it is where the zone boundaries are expected to move.
For insurance, the exact address counts for far more than the area average. A home well outside any modelled extent should be insured on normal terms. A home in zone 3, or on a road that takes surface water, may face higher premiums or excesses and more questions before a policy is offered. Get a quote on the specific property before the survey, not after.
Taking every measure together, surface water included, about 12% of postcodes are rated high risk on at least one measure, about 11% medium and about 21% low. These bands overlap with the zone figures above and are not the same measure. A postcode lands in a band here if any one indicator puts it there, so a single low spot on the edge of a postcode can be enough.
Counting properties rather than postcodes, the Environment Agency's rivers-and-sea mapping lists 1,752 properties in postcodes that carry some risk. Of those, 115 are at high risk, 51 at medium, 115 at low and 2 at very low. Of the high-risk properties, 73 are homes. Postcodes with no river or sea risk at all are not included in these figures.
In the Environment Agency's flood extents, about 1% of postcodes fall in the high-risk extent without defences taken into account, and about 1% with them. In this model, defences make almost no difference to the share of postcodes at high risk. "Defended" in these figures means a defence appears in the model, not that the house behind it will stay dry. The Environment Agency records 29 past flood events in the area, the most recent in 1981, and that one was caused by water overtopping the defences.
The shoreline management plan's policy for this stretch of coast is to hold the line, over 20, 50 and 100 years alike. That is a stated intention to keep maintaining defences, not a promise and not a defence that already exists. For the Pulborough area it is largely background: the coast is about 9 kilometres from the nearest postcode, and only about 1% of postcodes fall under a shoreline plan at all.
The nearest tide gauge, at Portsmouth, recorded sea levels rising by about 2 millimetres a year over its record from 1962 to 2023. That is a measured rate from the past, not a forecast.
Overall the flood risk here is middling. Most of the area is untouched, but a real minority of streets are at risk, mostly from rain rather than the river, and no area average will tell you which side of that line a particular house is on.