Need help finding a leak in liner pond.
I have a 30-50 gallon a day leak. The leak has been there for a couple of years, and I am getting tired of adding water all year long, even in the rainy season.
I have seen no sign of wet earth around the pond perimeter.
My system is three ponds that share circulation. I shut off the pump and let the system stop all circulation. Two of the ponds showed no loss of water even after three weeks, so I know the leak is in the third pond. The third pond dropped about a foot and then stopped dropping, so I know the leak is somewhere on the current waterline. I also know the leak isn't in the waterfall or other connecting passages.
Here is the problem. I have looked all around the perimeter and can't find the leak. There don't appear to be any obvious holes. If anyone has any tips for what to look for, or how to find the leak, I would like all the help I can get.
The liner is about ten years old. The pond in question has always been kept full so the leaking area has always been under a foot of water until now. The area of the exposed waterline is mostly pretty vertical. The pond is dug into decomposed granite which produces a fairly smooth hole. I have had a few moles digging around the pond over the years. I get a little ice around the edge in winter, but it never covers the whole pond. I do occasionally have deer fall into the pond. I have had a couple of perimeter rocks become dislodged and end up on the bottom.
It is a fairly large pond with some hefty koi, so replacing the liner is something I would like to avoid if I can. Catching the fish and replacing the liner would be a major task.
OK. What should I be looking for? And how do I find it?