We're pretty short on rain but I'm filling at a rate of about half an inch per day. I'm sure I'm losing water to saturation in the ground and evaporation but I'm not sure how much that is. I would guess the spring flowing in is probably 20ish gpm but that's just a guess. I don't see much seepage below the dam different than when the core was being put in and the stream was damned up farther back. You can see springs just feeding in all along the sides of the stream bank below the dam. I don't think I have anything going past the core. It was dug down 12 feet the entire width of the dam and back filled with good clay.