River Swirls

I haven't posted anything for a month and I feel like I'm in a bit of a rut/funk, photographically speaking. This is from the other night when I tried to get a shot of geese flying against a blazing sunset. I know what you're saying,"no geese, no blazing sunset". I saw this cloud formation and started looking for a FG when I spied this eddy on the river. The sun had set by now and there was not much light left. I've tried to brighten this up and to bring out the foam in the swirls but now I'm noticing a fair bit of grain? in the sky. Compression artifacts? Anyways...
Xsi,10-20@10mm,4&8sec@f8,ISO100. There wasn't enough movement in the clouds so they just looked OOF on the longer exsposure so I blended in the shorter exsposed sky.