Rufus Catfish,

Yes, I would try less drastic measures first. I had a leak in an overflow pipe too. My contractor did not even put a collar around the pipe and it was just a matter of time before the water worked around the pipe. If your overflow pipe is just a simple horizontal pipe and at the waterline I would dig it up, fill in and pack the earth down and put in an above ground overflow consisting of rock rip rap possibly funneling into a pipe that is above ground. It's known as an emergency overflow in some circles but it is foolproof and trouble free compared to a pipe underground. This is what I have on my warmwater pond and lined with landcaping size stone it works like a champ.

If pigs could fly bacon would be harder to come by and there would be a lot of damaged trees.