Alter Aeon Online Help

Keywords are:  'skill survivalist swimming'

Skill: swimming                 Lvl  5  Any  (85%)
                                (helpful)   

The swimming skill is used automatically when needed, like the dodge and parry
skills.  It allows one to swim across bodies of water (or other liquid, with
the proper protections), and expert swimmers have the advantage of being able
to make brief dives without the aid of spells.

A character with the swim skill will not need to carry around a boat. The higher
your swimming skill, the faster you will be able to move through the water.