Several years ago my FIL lowered a 3 acre pond via siphon, then had a large track hoe come in and reach what he could from the bank (not the dam). Stacked the silt in a "windrow" along the bank. Probably only spent $1000. A good track hoe operator can toss a lot of silt at $120 per hour.

After drying out a year or so the he used his own dozer to spread the silt out. The pond has row crop in the drainage so silt is an issue. A new 1.5 acre pond has been built above it so it takes some of the load.

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