I have a Kamatsu 200. I don't remember the boom length. I think it can dig to a depth of 19 or 20 feet and has a reach of 31 or 32 feet. Pretty standard rig with a weight of 23 tons or so. It does a good job; but it sure seems that you can't really reach that far with it when trying to clean out a pond still full of water. I remember seeing a big trackhoe with an 80' boom down near Sikeston Missouri. They said they used it to clean out ponds and rice paddy canals (or something like that - we don't grow rice around here). If you want to really make progress though, you need a machine like this http://www.komatsuamerica.com/index.cfm?resource_id=113 with an extended boom. It could probably do a good job.

I spent $28,000 for mine (well used) several years ago and have spent several thousand more on it since. They can do incredible things, but they are also expensive to purchase and maintain. For most, it is probably cheaper to hire. They are fun to operate though. \:\)

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