ML,
My friend just dug a pond a large tractor and a huge 8 yard dump scraper. It took about a week from start to finish. From what I've seen, it's easy to create ridges and trenches with the dump scrapers if you have room to maneuver. You can adjust the cutting depth "on the fly", making it very easy to get creative. With a 4 yard or larger dump scraper and a 125 HP or larger tractor, you can really make the dirt fly. It's the most efficient way to remove dirt from point "A" then transport and dump it at point "B". The implement is always killing 2 birds with 1 stone.
The dump scrapers are also very good at building up levees and constructing roads and dams.
