Mostly no, but the rain is a bigger worry than the river. Only a sliver of Liss sits in the river flood zones. About one postcode in eight rates high on at least one flood measure. The area has no recorded history of flooding. The River Rother isn't the main thing to check; the street and the drains are.
The Environment Agency's river-and-sea flood zones barely reach Liss. About 1% of the area's postcodes sit in flood zone 3, the highest-probability band, and about 2% in flood zone 2. The two zones don't overlap. Zone 2 is the medium-probability fringe beyond zone 3, not a bigger area that includes it. Either way, river flooding here affects a narrow strip, not the village.
Surface water is where most of the exposure is. The river zones leave it out entirely, which is why a house outside the zones can still come back with a flood flag on a search. Heavy rain with nowhere to drain doesn't care which zone a postcode is in, and the property listing won't mention it either.
Looking ahead, the Environment Agency's climate-adjusted flood zone covers about 6% of Liss's postcodes. That's still small, but it's larger than today's zones, so a buyer planning to stay for decades should look at the climate version of the map as well as the current one.
For insurance, a home outside the zones with no surface-water flag should be routine to cover. A home that carries a high rating on any measure may see that show up in the quote. Insurers price by the exact address, not the village, so get a real quote on the specific property before an offer becomes an exchange.
Counted by postcode, about 12% of Liss's postcodes rate high on at least one flood measure, about 20% medium and about 32% low. "At least one measure" includes surface water alongside rivers and the sea, so these bands overlap with the zone figures above and shouldn't be added to them. They answer a wider question: whether anything at all might put water near the property.
Counted by home, the Environment Agency's rivers-and-sea mapping lists 16 Liss postcodes with some risk, covering 439 properties. Of those, 8 are at high risk, 22 at medium risk and 108 at low risk. Only five homes are at high risk from rivers or the sea. That's a small number, and each of those owners will already know exactly which house it is. Postcodes with no river-or-sea risk don't appear in this count at all.
On defences, about 1% of postcodes sit inside the modelled high-probability flood extent with no defence, and about 1% with a defence present in the model. The defended figure is no smaller than the undefended one. Having a defence in the model means something exists between the water and the house. It doesn't mean the house is safe, and a seller who describes the property as "protected by flood defences" is describing a model, not a guarantee.
The nearest tide gauge, at Portsmouth, recorded sea level rising by about 2 millimetres a year over its record from 1962 to 2023. That's a measured historic rate, not a forecast, and for an inland village like Liss it matters mainly through the rivers that eventually drain to the coast, not through anything coming up the high street.
There's no recorded historic flooding in the area. That's reassuring, but it isn't proof that flooding has never happened. It means none has been recorded in the dataset, and a heavy summer storm doesn't always make the record.
Flood risk in Liss is middling: low from rivers and the sea, more noticeable from surface water, and dependent on the individual street. Check the exact address before you pay for the survey.