Coming in late on this one but would like to add something if possible. The core trench through the center of the dam is a good idea, but difficult to do sometimes. If the water is passing through the dam the material could be so wet it would be hard to manage. The sides will sometimes cave in and be almost impossible to get cleaned out properly. There is a roller that will attach to a track hoe that will do a fair job of packing. If the pond is dry and you do not know if you should plate the bottom. All you need to do is dig a hole with a pair of post hole diggers (hand held) fill it with water and see what it does that will help you make the decision. Otto
