Sort of surprised me to see ...
Swamp stage this and last September were pretty much the same.
But that's just one point.
Looked at from a whole the two summer's couldn't be any more different.
Last year's summer wet season started late (thanks to a deep spring drought) and ended early (thanks to a lack of tropical storms.) Compare that to this summer wet season which, thanks to the winter El Niño, has been pretty much wet all year long.
Hydroperiod, not water depth, is the critical hydrologic driver in the swamp.