It slows down.
Work Step by Step
The refractive indices of air, water, and the human cornea are 1.000277, 1.330, and roughly 1.38. The higher the index, the slower light travels (as discussed on page 526). Therefore, the speed of light decreases as it passes from the water into your cornea, though not as much as when light passes from air to your cornea. Source for data: Wikipedia contributors, "List of refractive indices," Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/wiki/List_of_refractive_indices (accessed May 1, 2016).