Ditto to what was said. That pipe is toast and there is no "fixing" it. If you had a dam and enough fall behind it a siphon system could be installed. If not, then the only option is drain, remove/replace. I wouldn't even tr to fill or plug it in that instance. If that were to leak around the plug, then you'd be back to square one again and have to spend the $$ all over again to rip it out.

If the pond does have a dam, then you have more work ahead of you and a lot of knee time praying in the future. ALL the trees on the dam that are smaller than 6" DBH need to be cut/killed and any that are over 6" DBH need prayers that they never die as long as you own the property. If the >6" DBH trees die, there is a possibility that when the roots decay the water might find a path of least resistance to go through the dam and leak water out of the pond. Even possibly causing a dam failure (worst case).


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