How long was the exposure? Did you use a GND filter as well?
The wash in was just over knee deep....wellies don't go that high....lol
About a 1 second exposure for this particular water speed and I just used a polariser to make the colour pop a bit, darken the skies and lower the reflections off the water.
I stopped using GND's about 4 years ago, I was experimenting with them in the early Digital days and then realised that a simple blend of two exposures usually does a far better job. I'm not against the use of GND's but I don't really see any practical benefit any more. I used to have a set of Lee hard and soft, reverse grads and a set of coral. Very nice results but nothing that I can't do better and more realistically just using White Balance and a pair of well judged exposure blends.