Water is a well-known and fairly widely discussed problem Buzzzzz. We'll be working on a major overhaul to the water rendering in the near future (which will enable transparency among other things). The results of that won't be seen for a few months I'm afraid, but I think you'll be pleased once they're available. In the meantime you can try reducing displacement or overall complexity/detail of the water. When a lot of interreflection occurs, as on a rough water surface, crashing tends to occur more frequently.
By the way that looks like a St. Helens scene there, and a superb one at that. I fear it may put mine (in progress) to shame.
![Sad :(](https://www.planetside.co.uk/forums/Smileys/fugue/sad.png)
- Oshyan