As psychology tells us, the more time we spend around anything, the more likely it is to show up in our dreams. But, you can also have strange dreams in which dogs are in situations that you have never seen them in real life and dreams where you can't place how you would have ever had that thought, for dreams like this, there is dream interpretation.
If you have a dream in which you see a dog drowning then this means you might be worried that you are not going to be able to do something. Dogs are known for their signature paddling style called the dog paddle. They can paddle away to their heart's content to get through the water and they are really good at it too. All they need to do is work up a little momentum and then paddle away with the protection of the water around them to help them out. If you have a dream in which you see a dog drowning then it means that the dog symbolizes yourself. Dogs are really good swimmers and there should be no reason that they would drown. To suddenly conceive of a dog being unable to do it means you are suddenly finding fault in your own qualifications and your own abilities to accomplish difficult tasks that you previously felt confident about.