Yeah, you're right. The reason I needed to know if this was possible is because my friend wanted me to do this on his roller coaster that he made. He has a theme park of over 100 coasters, and they're all really big and cool, but the extra commands would make it cooler.
So the water would be right next to the track, which means that I can't place the barrier block right on the same block that the track needs to go, and even if I didn't put a barrier there, the water would just wash the track away each time the fountain went up.
I don't think there is a way to resolve this issue about water that doesn't update, but I came up with a solution with about 60 commands per fountain.
Once again, thanks for trying to help!