Had the same problem until last week. I have a single stand pipe that runs through the dam and empties into the pasture behind the pond. I had a steady stream of water coming from the leaky pipe. We are currently in the middle of a 50 year drought and my pond is as low as I have ever seen it so I thought this would be the perfect time to fix the pipe. I looked out the window last week and my pipe was GONE!! I guess the lack of water to support the pipe coupled with plenty of rust did it in. This is good and bad. Bad because until I fix the pipe my pond will have hardly any water. Good in that it is now short enough to be able to work on.

Question:
I am planning on running 6 inch PVC through the pipe in the dam, putting on a 90 and then running the 6 inch PVC up as a stand pipe. I am going to fill in the gaps with concrete and cover the whole seam with a rubber pond liner.

Does anyone know of a good ruber cement or some type of adhesive that I can glue the pond liner to the existing pipe and pvc to make a good seal? I need something that can stand to be under water continuously but not affect the fish.

Thanks!

Scott <><