Pond Boss Forums POND CONSTRUCTION Renovating a Pond or Lake? Old pond, newer leak?

Hi folks,
We purchased a property this spring with a ~ 1/4 acre pond. The pond dates back at least to 1967. Unfortunately, the dam has lots of trees - pines and deciduous - on the back side. It's loosing water pretty fast, down about 4' during what is a farily wet summer here in western PA. I know I need to cut the trees down. Question is, assumimg tree roots have comprimised the dam, is it likely that reworking the soils on the pond side of the dam and re-compacting will return the dam to some level of effectivenss? I'm assuming there is a decent clay content to the soil the dam was built out of, but not likely an engineered core.
How would you all recommend moving forward? I'm thinking of tackling this next year, so I have some time to plan it out. Drain the pond first? Try to get some soil cores first? Or ???
Thanks for the feedback,
Dale

Hobbyman, I'm sure no expert, but still would advise caution about cutting down LARGE trees. Small ones yes, but large ones probably have extensive root systems which you don't want to mess with.

It may be that the most cost effective approach is to redo the dam, or leave it alone and deepen the pond. But please get a real expert to look at those trees before cutting...

I had trees on the dam and back of the dam of my 1/4 acre pond, plus lots of large trumpet vines. We dozed the trees off the dam, cut the ones behind, and reworked the pond completely inside. We did not rework about 2/3 of the dam. I fear roots were left inside the dam, and even with the clay packed on the pond side of the dam, the pond is still leaking, and seems to be getting slightly worse with time. If I had to do over, the entire dam would have been reworked, at least from the core inward toward the water line.

anthropic, thanks for the advice. Most of the trees are less than 8" in diameter. The pines were definately planted in a row, and I think that lead to a situation where the other trees got a foothold. I will have to decide how far out from the toe of the dam to cut - there are some larger trees near what I think was the orignial toe of the dam that I would like to leave if possible.

John F., sorry for your troubles. Sounds very similar to my situation and an approach similar to what I was thinking didn't work. I guess I'll have to bite the bullet and hog out the dam, at least to the crest. I wonder if a slurry wall down the center of the dam would be doable. Likely more expensive than just digging it out and rebuilding though.
Thanks for the feedback - likely safed me a lot of trouble.
Dale

I'm glad to help. Hoping my troubles save others from the same. Sadly, I was not on Pond Boss forums when the pond was renovated in August 2015.