Yes, parts of Grove are at real risk of flooding, and most of that risk comes from rain. Only a small slice of the village falls in the river flood zones. Close to one postcode in five rates high on at least one flood measure. A few dozen homes are mapped at high risk from rivers. Grove grew up along Letcombe Brook, and the brook was there long before the estates.
The Environment Agency's river-and-sea flood zones cover only a small share of Grove's postcodes. About 5% are in zone 3, the highest-probability band. Another 2% are in zone 2, the medium-probability fringe just beyond it. Zone 2 counts only the extra ring outside zone 3, which is why it is the smaller of the two numbers.
Surface water is the risk the river zones leave out. It is rain that falls faster than the ground and the drains can take it, and it collects in dips and roads wherever the rain lands. The Environment Agency's river-and-sea zones exclude it entirely. That is why the broader postcode measure further down this page returns much higher shares than the zones.
When the Environment Agency adds its allowance for a changing climate, the share of Grove's postcodes inside a flood zone rises to about 7%. That figure is a modelled scenario of where the zones would reach under heavier rainfall and higher river flows. It shows the direction things are expected to move.
For insurance, the difference between the street that floods and the one next to it can be large. A home inside a mapped flood area, or one that has flooded before, can expect more questions from insurers and a higher premium. Get an insurance quote for the exact address and check the Environment Agency's long-term flood-risk service for that property while the price is still being agreed. Grove's risk is patchy, and only that check tells you which side of the line your house is on.
Measured a different way, about 17% of Grove's postcodes rate high on at least one of several flood measures, with surface water counted alongside rivers and sea. Another 18% rate medium and around 42% low. Each postcode takes its worst rating from any of the measures, so the shares run much higher than the river-and-sea zones alone.
Counting homes gives a more useful number. The Environment Agency's river-and-sea mapping lists 30 Grove postcodes that carry some risk, covering 576 properties. Of those, 73 are rated high risk, 18 medium, 78 low and 50 very low. Postcodes with no river or sea risk at all are left off the list, so those 576 properties are only part of the village.
When it comes to defences, the Environment Agency's model shows about 5% of Grove's postcodes inside the high-risk extent with defences left out of the model. With defences included, the figure is still about 5%. Including the defences makes no difference here. The Environment Agency has four recorded flood events in the area, and the most recent was in July 2007. On that occasion a main river overflowed its channel at a point with no raised defences. Even where the model does include a defence, all that means is that something is in the way of the water, and the house can still flood.
The nearest tide gauge is at Portsmouth, where the sea rose by about 2 millimetres a year on average between 1962 and 2023. That is a rate recorded on the south coast. For Grove, the water to watch is Letcombe Brook and the rain running off the fields, and the sea comes a distant second.
Flood is one of Grove's real weak points. For most buyers the risk is manageable, but it varies street by street, and the next street is not always the safe one.