I believe it is the Matterhorn (side near the sub lagoon), but Pengy can correct if wrong..
You are correct! Its actually on the side facing Pixie Hollow if I remember correctly. I was waiting to meet up with Barbara who was in Pixie Hollow at the time. I have some other tight shots of water effects that I'll at some point post. Sometimes if you zoom in you can't really tell if your in Disneyland or somewhere else entirely.