Thank you for the update DrCalm.

Based on the information given, my assumption is that this is caused by the graphical settings and resolution combination. Basically, it looks like an aliasing artifact due to the distance from the water and the real-time reflections (reflections are probably rendered at a lower resolution causing some sort of pixelation at this distance). The lines probably appear because they are under just the right circumstances to create that kind of artifact. Unfortunately, the only way around it would be to change either the resolution or the real-time reflections.

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