you say that as if it's vital mechanic. besides, why are you worried? there's several ways you can swim in Terraria
Terraria Community Forums
Scarecrow
XenoCat
I bet swimming will be completely forgotten, yeah, if you touch water you DIE.
FaZe EPIX
Halo Logic?
Water Filter Salesman
Nah, there probably won't be water in Otherworld at all 
Scarecrow
it'll be that one thing from the previous game that was super cool important and or mysterious, and will only be mentioned through random voice lines from npcs
Cenx
We actually cancelled it to bring you Swim Simulator.
Scarecrow
thanks @[38EpicCriddle]
thanks a lot you... you... meanie!
EpicCriddle]thanks a lot you... you... meanie!