coz you can only see them if you change the water digits(16) to the grass digit(0) or any other walk able surface.
lol just use a bridge
you cant place on the blacked out/gray area because you have not "explored" it yet and you cant swim/ move in water to "explore" the area.
if you click and hold on 1 side, then drag to the over, you will have a bridge blueprint that goes into unexplored area
also, i made a fully automatic apple tree farm before you uploaded your post, so IN YOUR FACE
oh wow thx for the info bro!