Giles.floydub17_ESO wrote: »It is merely a hatch in the floor down in the basement/dungeon. It goes out to the water next to the Manor. One can also jump over the wall at the edge to get down to the water and come back through the tunnel. It is not really secret.
The character cannot swim far out due to slaughterfish, but it has a small area of water accessible, but no dry land to stand on.
Is it a neat feature, yes, but not really usable that I can see.
After they expanded the area without slaughterfish there's room to put stuff down to make your own docks or the like. I recommend the 100g items from the housing vendor in the grocer's in Coldharbour.