To dream that you are underwater suggests that you are being overcome with emotions and are in over your head regarding some situation. You need to gain greater control of your life.
To dream that you are breathing underwater represents a retreat back into the womb. You want to return to a state where you were dependent and free from responsibilities. Perhaps you are feeling helpless, unable to fulfill your own needs and to care for yourself. Alternatively, breathing underwater is analogous to being submerged in your own emotions. Dreaming that you are flying underwater represents control over your emotions. You are comfortable with confronting your feelings directly.
To see houses under water implies that you are very comfortable with your own emotions. Alternatively, the dream may be a reflection of your housing situation. Perhaps you are “underwater” in your mortgage.
To see objects underwater in your dream symbolises your suppressed feelings as represented by the objects. The objects may trigger some emotional memory which you still need to confront and work through. For example, children’s toys or bicycles refer to an emotion that you suppressed in childhood. To see a car underwater in your dream points to feelings of regret or sadness over an abandoned goal.