What's the easiest way to clean out a small farm pond ?

It is not very deep because of all the leaves and guck that have accumulated on the botton. It does still have fish in it because we have caught several out of it. We can't afford to hire someone to dredge it and are afraid to walk in it to try and rake some out of it by hand, we have seen some very large snapping turtles come to the top. Any suggestions would be greatly appriciated.