There's just the one place 6-7m below sea level really. If I recall correctly the current infrastructure is capable of protecting against sea levels 6 meters ab

There's just the one place 6-7m below sea level really. If I recall correctly the current infrastructure is capable of protecting against sea levels 6 meters above average, but that includes tides and storms. A 2m rise in sea levels could mean that all parts of the defence need to be raised a further 2m, and some of the natural defences (dunes etc.) might no longer be adequate.