... I couldn't believe how flat the bottom was. I was looking for humps and drop offs in about 15-25ft of water and had no luck.
That is true about EM. It is pretty flat, for the most part. Except for the well-known humps and ridges, most of it appears to be rather soft, flat bottom. There are quite a few ridge lines and 'rough terrain' areas about 250-350 yards east-northeast of the Dam area [you'll have to look at a good TOPO map to see them], but I have rarely marked any fish in those particular areas. I have heard of others having success in these areas, but not me.