The lake located at the coords X: 0.81, Y: 0.92 just under Krsnik has a visual bug. This same visual bug is also present on both ends of the Livonia river.
Map image: https://i.gyazo.com/1d8811d4e97f306edbb2edb75c33354f.png
Bug image: https://i.gyazo.com/09c1a3683c36c98f2199ddd0127f68c5.png
No steps required to repro.
This issue can easily be solved by extending the water out a little further, as for the ends of the Livonia river I think maybe an ocean surrounding Livonia would be ideal, this would also solve the issue of players driving out there and getting their cars stuck in the ground and would also be good for the new boats.