Pool Leak

[Joe56]

Greetings,
New here, not new to pools. We have had the same 15 foot round above ground pool for about 20 years and have changed the liner 3 times. The present liner is no more than 3 years old. Living in NYC, I close the pool every year. I drain down to just below the return inlet. Just as in all the previous years the winter water level has remained constant. Within the last two weeks it has gone down at least a foot below the return inlet, but it has stabilized since then. I haven't opened the pool yet, but obviously I have a leak. I have gravel and plants all around the pool base so it's next to impossible to see where the water is exiting. In all my years of having a pool, this has never happened. If a plant root pushed through, the leak would theoretically be from the bottom and the pool would be empty by now yes? I am puzzled as I can't figure out what would cause a leak at mid depth of the pool.
Thanks for any input.
Joe56

 

[Texas Splash]

If a plant root pushed through, the leak would theoretically be from the bottom and the pool would be empty by now yes?

Correct. It's somewhere around that new (Lower) waterline where it stopped falling.

 

[Newdude]

Is it still covered ? We've been pounded by rain lately and you could be picking up what you're losing. If its still covered the cover may be compromised and letting new water in to somewhat match the leak. Or the ground is too saturated to let more out.

 

[Joe56]

Correct. It's somewhere around that new (Lower) waterline where it stopped falling.

Thanks, now that the cover is off, the search begins.