I like that idea. The only way that I think it could be improved upon is to smooth out the dirt surrounding the hole so the liner has a flat spot to seal against. What you are planning on doing is making a super large flapper valve.

Other than getting some heavy equipment in there to dig out the hold and plug it, I think that's the only option.

Please let us know how it works. I bought some liner off of e-bay cheaper than I could find it from any supplier.


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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).