Thanks.
The old pond on the property is very old and has 100 ft trees growing on the dam slope some of them dead. The overflow pipe buried in the dam is corroded and shortened by several feet.

The trees will have to come out to restore the dam integrity and the pond.

Filled up the overflow pipe with concrete to see if the pond will hold water> Amazingly it filled up and seems to hold its level. The dam has a very gentle slope on the water side dropping perhaps only a couple of feet 50 ft out from shore and then going deeper perhaps 8 to 10 feet or so.

Pond has not overflowed yet after a week or so but made a swale cut with the loader for a spillway away from the dam itself.

Thinking about cutting a channel into the pond and drain it and then dig out the tree roots and rebuild the dam. Should be able to use the original dirt from the dam to reconstruct it and in the process clean up the bottom and make it more uniform and deeper.

The watershed feeding it is not very large and during dry seasons it gets very little water. There is a 6 inch pipe draining off a spring from the log cabin basement that would be easy to route over to the pond. Perhaps extending it 30 ft will make it drain to the pond and looks to be a good flow of perhaps 20 gals per min that flows year round.

Rebuilding the dam is a process I need to learn more about. How to compact it during the fill etc

Any thoughts would be welcome