trapsht, Why don't you think pumping is feasible? I have the same question as Dave, springs or ground water or surface run-off? I renovated my pond, and had to dig in ground water. You'd be suprised how much water a 15,000 gph pump can move! I used one for doing my pond, and it helped me to be able to see to dig and not dig in the water.

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).