You can see how the colors of the water appear different to the eye or the lens because water of different depths filters out different colors of the light spectrum. So the shore water appears more of a greenish color whereas darker water takes on more of a blue cast. Crater Lake in Oregon is a good example of this as well. Its inky blue color is partly a function of how ridiculously deep it is. Colors of this photo are OK though the rocks need some work. You can see the trail going along in the upper right hand corner just a bit above the lake.