Lance,
Here's a few nuggets to sooth your worries.
When a pond is built, soils are dry. Soils don't repel water, they absorb it.
So, when a new pond first fills, soils act as a sponge, absorbing water. The keyway absorbs less, and allows a minimal amount of water to pass through.
All dirt leaks. If it didn't, we would see permanent puddles some place, somewhere. So, expect a little leakage.
Hot, dry weather exacerbates evaporation. Air absorbs water, too. So, the hot, dry summer air absorbs water from your pond.
Conversely, cold, dry air also absorbs water. That's how ice disappears when temps stay low. It's called, "sublimation".
Three feet of water loss from a new pond is expected. I would be totally surprised if you had not lost that much.
Always remember this, we only borrow water, we never keep it. Water seeks the path of least resistance, leaving, moving all the time. Evaporation, overflow, seeping laterally, moving through soils, or animal bladders, water is continually on the move. Our job is to manage it.
Sounds like you built a good pond. Hang in there, and see what happens during a season or two of "normal" rainfall.
