It looks really great Thomrey, your colours work beautifully together and I always love seeing different styles of water! And feel free to play around more with it; there's always one of us here to give some feedback!

In regards to the water transparency, as Tonnichiwa said, it definitely looks a little strange over the trees. Unfortunately, if you just make it less transparent I don't think it will help and still look like the red weed from War of the Worlds! Changing its colour may help but I still think it would look strange. Wait to see if anyone else has any suggestions, but to me there are two options:
1) Do as Tonnichiwa said and put gaps in the treelines, or
2) Erase the river part that goes over the forests, so that you see their source on one side and then them coming out on the other, as the trees would obscure it (depending on the aesthetic you want). To me this second option seems the easier to try, but then again you may not want to make parts of your rivers unknown.

Anywho, these are just suggestions and feel free to ignore them if you want!

I look forwards to your next update because it really is looking nice and good luck with whatever you choose to do!