I'm having my pond re-dug (cleaned and enlarged) and I've talked with a few contractors already but I'm not really sure what I want to do with the pond edge. I have a small dug pond with clay soil throughout, currently the pond edge is pretty much level with the surrounding ground. I have a small low area where water sometimes rushes in with heavy spring rains and brings leaves and debris from a small stand of woods that's low lying and near to the pond. My pond also overflows maybe once each spring with heavy rains but recedes quickly, usually in a day or two.

I see some excavated ponds where the pond edge is built up higher than the surrounding ground, I guess this is called a berm. When a dug clay pond is bermed up like that I assume that it doesn't get watershed and has to fill up with only rain? One contractor said my pond will never fill if I put a small berm around it and another contractor says it will. Does ground water move through clay at all? If there is enough rain, will the berm act like a bowl and hold the water above the surrounding ground?

I'm having a ledge cut 6' into the pond to hold cobblestone on the 3:1 slope. If I have a berm made I don't want it to be very high, but how high? Can I reasonably ask for the edge to be only 6" higher? My pond always fills to the top in the spring and during the summer, a normal summer, the water level usually drops about 12"-18" max. My stone will be only 6' in to accommodate for water fluctuations and I would like most of it to be under the water but I also want to be able to run my riding mower up to the stones. I want to keep the water as clean as possible.

Construction is scheduled to start next week, the pond was pumped in the spring and has dried up nicely. What should I do? Berm or no berm? A diagram would help greatly to show the contractor but I'm not good at drawing this out. I need help. confused

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