Doug Stenson AKA Lakedoctor does a lot of ponds and lakes in Indiana. He has posted here before, just not lately. I think is based somwhere around Indianapolis. It seems like he told me he used a general guide of $10,000 per acre; but it probably depends a lot on the actual site. It sounds like your lake would include some good features that most don't factor in.

I was able to have my dam done (between two hills) by a local contractor for whom my nephew works for $14,000 leaving me a lake of approximately 10 to 12 acres. They used a 4:1 slope and said they figured the dam contained roughly 43,000 yards of dirt if memory serves (212 feet thick at base, probably 6xx feet wide, 3x feet tall). Frankly, I think they probably lost money doing my dam. I did have them do a bunch of topsoil work for roughly $7,000 so they probably made some doing that.

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