A dream with a swimming pool can symbolize your relationships with others or the need to acknowledge your feelings or emotions. Perhaps a relationship in your waking life needs more attention or structure, or you need to deal with your emotions or hurt from your past. You are in need of emotional cleansing.
The depth of the swimming pool can symbolize the depth of your emotions or how deeply you have buried these feelings within. Swimming to or in the shallow end of the swimming pool can symbolize something that can be dealt with easily, whereas swimming to or in the deep end would highlight something that would require more work to confront.
An empty swimming pool can highlight lack of emotion in some part of your waking life.