Yes. Abbey Wood carries a serious flood risk from the Thames, and defences are what hold it back. Well over half its postcodes are in the highest river-and-sea flood zone. Take the defences out of the model and roughly the same share falls in the high-risk area. Put them back in and it drops to about one in ten. Most of what keeps the area dry has been built by people and has to be maintained.
The Environment Agency's mapping puts about 58% of Abbey Wood's postcodes in flood zone 3, the highest-probability river-and-sea zone, and about 1% in zone 2, the medium-probability band beyond it. The two bands don't overlap, so zone 2 is the extra fringe beyond zone 3 and is meant to be small. Here the high-probability zone is far larger than the fringe, so most of the risk is in the top band.
Surface water, from rain that can't drain away fast enough, is a separate risk. The Environment Agency's zones don't measure it. In this answer it appears only in the combined postcode measure further down.
Allowing for climate change, the agency puts about 54% of Abbey Wood's postcodes in the flood zone it expects. The coming decades bring no real relief, and the picture stays much as it is now.
Insurers price flood risk by address, and an address in zone 3 behind a defence still gets read as being in zone 3. Get a buildings insurance quote for the exact property early in the process, while you can still change your mind cheaply.
On a wider measure that folds in surface water alongside rivers and the sea, about 16% of Abbey Wood's postcodes rate high on at least one of those measures, 23% medium and 43% low. A postcode counts if any one measure flags it, so this is a different count from the flood zones and the two shouldn't be added together.
The Environment Agency's rivers-and-sea mapping also counts properties, and it lists only postcodes that carry some risk. Across the 311 listed postcodes in Abbey Wood it counts 8,630 properties, with 404 at high risk, 334 at medium and 295 at low. The other 6,330 are rated very low. Of the high-risk properties, 377 are homes.
Here is the question that matters most. Without defences in the agency's model, about 58% of postcodes fall inside the high-risk flood extent. With defences present in the model, that falls to 10%. A defence shown in the model is not a promise that a particular house stays dry, because defences can be overtopped or fail. The last flood on the agency's record came from the sea in February 1953, caused by a breach of the defences. That is one of 217 flood events recorded across the area.
The nearest tide gauge with a long record is at Dover, which measured sea level rising by about 2.2 millimetres a year between 1961 and 2010. That is the rate the gauge recorded over those years. Dover is how far you have to go to find a gauge with a record that long.
Flood risk is Abbey Wood's real weak point. Most of the area is in the highest river-and-sea flood zone and relies on defences to stay dry.