1/8 acre is small enough it should not be too bad to re-do even if you have to drain it with a pump and completely re-dig the whole thing. In fact that is likely what you will need to do.

If the current pond is still in decent shape AND you have enough property in a suitable location, it might be better to just leave the current pond as is and dig a separate new pond the size you want. It very likely will cost no more and maybe even less to dig a complete new pond than what it will cost to deal with the muck and mud cleaning out and expanding the old one. Then you would have two ponds, with two different management options, or a main pond and a forage pond.

Something to think about.

John

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