Beautiful river scene but definitely over exposed. The trees give away the time of day you shot this. Sun looks to be too harsh bouncing off those trees and across the river. Maybe try a neutral density filter or shoot it in a different time of day for those type shot. Your river flow looks awesome though. Almost like a painting.
Nice scene, great motion blur. I think I might have cropped it a bit tighter and worked on eliminating the mottled light as much as possible so my eyes would be drawn right to the water, but it's a nice shot.
I think the contextual scenery is a bit blown probably due to the long exposure. Nice scene. But I'd like to have seen maybe blues in the sky or cloud definition and more details on the grass. Perhaps some light HDR'ing on the image would have given you that while maintaining the motion blur.