Ok I was was wrong, I for some reason thought the water level was some where between A and the inlet to give it more storage before it started to drain. Could you drop air vet pipe 2 feet lower than point A. So when it would start to draw it would not stop tell air is let in 2 feet lower. So a system like this could be put in on a old pond with out cutting dam to or bellow water level.

61 acre water shed lake. bass, channel cat, black crappie, wiper, walleye, redear sunfish, blue catfish and bluegill. To many bullhead and common carp
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