This is great! I love how the body of the serpent rolls and curves with the waves. It mirrors the water in the same way a sand snake's body follows the contour of the little sand waves. The image gives a great sense of the creature in motion, and really helps to illustrate how this will look in action.
The pale yellow background was a nice choice, too. That color, with the look of the waves, reminds me of a Japanese wood carving.