The tidal wave symbolizes the confusion the dreamer has at this time of his life. Perhaps he is stressing out a lot about some matter. The dream suggests to do something immediately about it, because the stress is too hard to cope with. The tide wave is the symbol of your survival instincts either.
Dream dictionary: Tidal Wave dream meanings
If you see a tidal wave, then it shows some aspects that must be faced as soon as it is possible. Perhaps there are suppressed feelings and emotions that are unsorted.
The dream about calm and transparent waves announces you peacefulness and calmness in your inner world. Now you are ready to clear your thoughts and make a very important decision which will change your current life. If you hear how waves break of on the shore, then a dream will bring you calmness and relaxation period in your life. To be in a tidal wave shows your power to withstand against negative events or thoughts. In the dream to see muddy or dirty waves denotes to mistakes that you have done in your life while making important decisions.