The Default Water has 2 bump layers in it, Noise-Smooth, and waves. Try selecting the Waves layer and on the left, below the window which has the bump names in it, lower the Amplitude setting. I was just trying it. I wasn't able to see the lines, but I have seen them before. The lighting has alot to do with it. But I was able to create the lines, with the Amplitude control, so that might also work to remove them.