Glitchy water level at the entrance to lake from valley #1567

This has been broken since we added the gossip stone to change the water level of the lake. I figured I'd put in a request to do something about it...

I checked in vanilla and the water works correctly, as you'd expect. (Though it's possible part of the behaviour we see could be a 1.0 bug.) What happens is, before the lake is filled, the stream coming from gerudo valley works fine. After the lake has been filled, the water always behaves as it does before the lake is filled, though it appears as it does when it's filled. If you lower the water using the gossip stone, the stream becomes invisible.