It's usually flooding that comes to mind.
|Can you see the year's where two wet season humps merged into one? Now, how about the deep droughts?|
But part and parcel with that definition ...
Is the implication is that waters didn't drop too low.
This year qualifies as "high water" not because it's reached stratospheric heights, but that swamp (and especially the cypress and marshes) have been holding water all year round.