When light travel from one media to another media, part of the light will reflected back to the original media.
Some of the light will enter another media and change it direction (due to change in velocity).
Yes, the wavelength of the light will change when enter different media.(only frequency will not change).
The wavelength of light in the water is different from wavelength in air.
You forgot that light must enter into our eye in oder to see it.
The path of the refracted light you saw, must be back to the air and enter you eye for you to see it.
So the wavelength is the same when light enter your eye again!