You have AO amount set too high for the snow shot. Lower it and that problem will be lessened. That will help with the water issue as well. And as for the water, the last time I checked, water in real life has a transparency to a certain depth. So those stairs would be fully visible. And the effect in the first two shots are really noticeable. And if it's noticeable in a still shot, it's going to be that much more noticeable in motion, in game. You can justify it's non use through denial all you want, it does make a difference.
Your roads could use a little parallax love too.
Edited by Slightly skewed - 8/25/12 at 4:18am