The windsurfer trails are leaving permanent artifacts in the water. When the camera moves these artifact "smear" and over time the entire water effect is ruined.
I raised this issue over on the boat attack water repository as well. I should point out I'm using the rendergraph-u6 branch. I uploaded some images that show it to the other repo, but I have seen it happening on this project as well. Just look behind the windsurfers, its pretty obvious.