Brettski...grab some coffee and a snack, this is a long one.

Actually the dam was closer to 8000 cu yds. Core trench is 16-18' wide and only about 24" deep, as the topsoil is very thin. The pond was dug to about 12', with no signs of any porous material, just very good yellow clay. The dam was compacted by a D7 dozer in 4" layers. When construction started, the clay was quite moist. We had to wait to start building because of excessive rainfall and very muddy conditions. After we got started, we went into a 5 month stretch of less than 2" of rain. This is where the problems started. Most of the dam has 6-8" of topsoil on it ( some a little more..some a little less ) The topsoil was used to level and smooth everything out and to give the grass something to grow on. About a month after construction, the cracks started to appear. Nothing too bad at first, but after 5 months of drought it got real bad. The cracks,3 of them, ran 6-7' deep, from inside the basin to the backside of the dam, and were about a foot wide at the top. I probably could have minimized the effects of the drought, if I wouldn't have been such a tight -ss and spent the money to water down the dam. But I didn't and so I've learned the hard way not only what I did wrong, but also how to repair some leaks. My NRCS agent and my excavator both thought the cracks would close and seal on their own, IF I got a few nice soaking rains before the pond filled. That didn't happen. The drought was broken by a 4" rain that fell in 3 hours. The pond filled to 3/4 full overnight. The clay didn't get a chance to swell before the water started running thru the cracks. My dam must be well constructed, because it didn't fail, nor did it wash big holes out of the cracks. The cracks didn't seal themselves.(can you believe it?) So, my quest to seal the cracks started. Crack #1 was the worst crack and really the easiest to repair. I spent a couple of mornings with a long rod and buckets of clay hand filling and packing the crack. it has never leaked again. Crack #2 didn't work that way. It still leaked afterwards. Meadowlark actually gave me the idea of how to fix this one....from the backside. It is now repaired. Crack #3 neither worked completely. It still seeps. Not alot , just enough to keep the ground moist. At this time I'm not too concerned about it. I plan to extend the dam in a year or two and the area of the leak is where the new section of dam will tie in. I will fix it then.
I hope this answered all your ?'s.

I'll start treating my wife as good as my dog when she starts retrieving ducks.
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