Spiritual Meaning:
Because a canal is a man-made structure it suggests an imposed structure, definition of boundaries or rigid belief.

Psychological / Emotional Perspective:
We need to structure our knowledge of ourselves to create a workable system.

Everyday Material Aspects:
A dream about a canal usually indicates that we are inclined to be rigid insofar as the control of our emotions is concerned. We may be introducing too much structure into our lives at the expense of our creativity.

Also consult the entry for Water.