One thing about long exposures of moving water is that some parts, including surrounding areas, like rocks, can end up looking out of focus rather than the intended soft and ethereal look (note the left bottom rock looks soft). So you have to watch for that and maybe take one shot with a faster shutter speed to compare.
I don't worry about blue or green or any other tinges, because if they are too pronounced, they are easy to fix. Usually set somewhere between true neutral white and the colour tinge.
Water blur is often overdone to the point of cliche. Having said that, like any good sunset, I still love them, if the result is a great image. But you should consider a shutter speed somewhere between blur and freeze and compare. Total blur is not always desirable and can render water milky and unattractive and often does. Believe me, I know, and only show you the good ones! Mind you, slow shutter speeds are sometimes unavoidable. The best blurs come at a right angle to the flow of water, such as rapids, rather than in front or behind the flow; Note that the speed of flow and amount of white in the flow (or foam) of the water can make or break an image, so do experiment. Large areas of white are hard to expose for and skew light meters' readings. And when doing PP with a lot of white, say to try to increase contrast, or correct, the large amounts of white start to appear overexposed.
My cascades series were done, in part, as experimental in-camera, multiple exposures. Hope this helps.
By the way, I would have preferred the image without the cluster of green foliage and ice- a simpler look. Try a little unsharp mask, it gives a better more defined look to the water movement. Sparingly of course.
JMR
