If I knew how, I could post a picture of the pond I built in 2004/2005 and you would not know the difference between who's photos are who's. All the way down to the rednecks in flannel shirts looking at the problem with a befuttled look on their face. Kidding man, well not really. We had 7 befuttled rednecks at my site. LOL 3 works, myself, environmental guy, and two NRCS guys. LOL Kidding, but we looked so similar to the guy in your keyway and the site is so similar looking, it is eerie.
You can search my "Holler" thread. The NRCS helped me as technical advisers. When we hit the spring, the local NRCS guy pulled in a "big whig" type of guy, over the region. What we decided was this. We decided to attempt to let the water do what it was trying to do. We piped. It was to the side of the keyway. We piped it from where we hit it, all the way outside the back of the dam. The environmental company I was using as advisors went straight up with the pipe as well. The contractors didn't like it, but he said we could pressure grout it later if we wanted. They must have hit the pipe 10 times as the dam went up. At any rate, after piping the dam through, a big rain came and it broke free more towards the middle of the dam, at the front, through a limestone fissure we did not see. So, again, we put a 4" pipe here and piped it towards the back, down the back to the middle, and out the middle of the dam. At the head NRCS guy's suggestion, so that we did not have this problem again, they put a plastic liner down, from the front of the 4" pipe to the back of the dam, from where the pipe was, directly to the back. Then, upon advice, we put a layer of gravel front to back, and put another plastic liner in. From there we started back filling with clay, coming up with the dam. So if the 4" pipe isn't enough, in flooding conditions, the sleeve carries the extra water, front to back and allows it gravel o run the original rock layer.
The dam was completed in early 2005. In Jan. 2006 we had a flood. The pond went up to over half full, and once the water table/runoff slowed, it begain leaking at a rate of 6" per day. Not knowing where it was leaking, we scraped the entire floor down to clay and put in a 1' to 2" liner. We compacted it all exept 1 small area I put fish structure, on the same side of the dam the original spring was hit. You might guess what I'm going to say. If you don't compact 1 area, it will leak there.
The drought hit, and I suspected a small leak but hoped for the best. Fast forward to May of 2009. We had a 100 year flood. The pond went up and started leaking again. As the water was rising, I was wading in the area above and in frong the orginal spring was hit, on the front of the dam, and guess what. The 65 degree water turned to 58 degree water in certain places. As the table lowered, it leaked at a rate of 6" a day until it hit it's level.
In June of 2009, I put 5 300 to 400 lb hogs into this area, fencing off maybe 1/4 acre. As the water came up, in October rains, I spotted the clear clean spring water coming out of the ground. You could almost drink it, right out of a hog slop hole. They sealed it up unto this spot, but I figured it could be better sealled with a 30,000 lb hog. So we scraped it down. We hit a verticle rock wall on this side, and saw small slits/caverns as well as sand and evidence of water removal. We dug it down, and removed any loose rocks. Then we bomagged good clay into the caverns and compacted the fire out of it.
This winter the pond went from 1 to 2.5 acres. It appeared to be leaking 1" a day, so I knew we were on the right tract. Now this leak appears 1/8 or 1/4", say 3/16" a day, so basically evaporation for a new pond.
I'm hoping for massive rains now.
My advice to you is this. You need to read my holler thread. Second, and most important, you need to determine the head pressure on that water.( I did not do this, as the thought never crossed my mind, at the time and it wouldn't have worked for me anyway, as I think I had low pressure due to the large fissure vs small amount of water.) Put a pipe in it, and seal it. Go straight up with it a few feet at a time. If it has pressure, and it would be good if it does, you can see how high it goes. If you have 20' of pipe in the air, and water is coming out, it has a lot of head/pressure on it. I would put a big pipe in it, and go straight up, and pipe it out the front of you dam, upon completion, giving the pond water. You will have to devise a way to keep it off of you during construction, maybe a few feet at a time. If no pressure, do what the NRCS people told me, try to let it do what it is wanting to do.
Good luck and I hope my experience is helpful to you. It was costly to me, and I hope it helps you out.
Last edited by Robinson; 03/24/10 04:39 PM.
