Blue Ocean & Clear Bathtub Water The color of water can seem very different depending on distance, too. A bathtub or glass full of water always looks clear, letting you see your reflection. This is because it is being viewed over a short distance. Actually, a glass of water is slightly blue In fact, if the volume of water was sufficientl large, it would appear blue. Depending on the water source, the color of wat is not always the same. In deep water, the water looks dark blue or bluis.