I used the slowest shutter speed that I could (1/8 sec) with a polarizing filter. You really need a neutral density filter to get those stunning water flow shots, however.
I fell in love with the big tree in the upper left of the picture. Something about it just looked perfect. Here's a closer crop to show off more of that tree. Less rapids, but the composition is more pleasing, IMHO.
Here's a view pointing downstream from the rapids, rendered as a landscape oil painting with SnapArt.