What would be the best way of using water with procedurally on-the-fly generated terrain?

Hi, I've got terrain generating depending on the player's position. Previously, I made use of Unity's free simple water by instantiating one water plane per piece of terrain. This worked perfectly and didn't have any noticeable performance hit. Today, I decided to move onto Unity pro's water with the same technique and my FPS plummeted quickly.

My terrain pieces spawn according to the player's position and de-spawn when the player is far enough away from them so there are on average, 45-55 terrain pieces active at once. 45-55 instances of Pro water seems to be the issue. What would be the best way of using water in my situation? I've tried spawning 1 water plane mesh per 8 terrain pieces but there were still about 7 water meshes active at the same time and caused a lot of lag.

Thanks!

Edit: I tried creating one water plane and attaching it to the player's X and Z position and it seems to be al-right. The only problem is that the shore lines "wobble" when moving at high speeds. Any way around this?