Symbolically, Water represents all that lies below the surface:
Water represents Our Subconscious. Our Subconscious is the
limitless creative ocean of our Divine Nature which has direct access
to The Great Subconsciousness of Creation.
Water is the realm of feelings, dreams, imagination, and intuition.
It is the realm of Spiritual and Mental Creation at the most subtle,
sensitive and sentient level. The Great Ocean of Our Subconscious
is where all the elements of creation, everything that is and ever
will be, already exist in their un-manifested form awaiting the
“Seed of Thought” to impregnate them.
Once the Subconscious is impregnated by the “Seed of Thought”,
the Waters of the Subconscious then protect, nourish and nurture
this new creation until it is ready for manifestation in the physical
realm.
We can picture the element of Water (Our Subconscious) as a
great ocean. When we look upon this great ocean we can only see
its surface. However, below the surface of this great ocean exists
all the mysteries and unknowns that lie deep below the surface.
The deep recesses of this great ocean represent the deep recesses
of Our Subconscious.
http://www.aseekersthoughts.com/2009/04/water-symbol-and-mythology.html