I don't think setting the water to detail is going to change anything. If it did, it probably just made the game lie about the r_speeds. I like that you've added a bunch of detail to your rock structure, but as FourthX pointed out, there are a lot of little gaps and overlaps that are kicking your r_speeds up (and make the map look bad). Sort added a really cool feature to BSP that allows you to get the clipping plane from the side of any brush. This is handy for dealing with brushes that don't quite line up. You can select the brush that protrudes, then get the clipping plane from the brush it's supposed to be flush against, and just carve off that excess area.
There are a few spots, like where the carbine rests on that little ledge, where there is a gap between the brushes. You need to make the ledge a little larger so it comes up flush with the wall or even overlaps it a little (overlapping is OK so long as two faces aren't on the same plane. The compiler will cut out the hidden faces).
To be honest, I'd get rid of the boats completely. They look cheesy (you'd need a model to pull that off well), and add to the r_speeds a lot. It's also really unrealistic the way they're mirrored and both have a hole in the exact same spot with the exact same shape.
I've uploaded your map to the beta server.