In defence I know the water is new, I am simply working in a situation where I have found an issue I have to redesign around rather than improvise.... and it is this.
The water table should in my case be round. I dont have a land editor. Corners like this appear many times in land relief because ultimately the land masses are cornered.

So shapeable, OR round OR a choice would be super. OR, the facility to transparentise the outer edges to invisibility!

In most cases I can rotate the water OR redepth it. Or or or or ... but in this case as in a few others I cannot use some of the more pleasant Cam angles because its unhideable.

In some cases its an impossibility.  

W.I.P. "Medieval Chinese Painting Exhibition" over 6 sets.
iCloneTutorials.com
No Imagination, no comment!