I have recently been told by someone who’s on his third pond that I could have a problem with the elevation difference between my pond and the creek that adjoins it. The creek is substantially lower in elevation that the pond is. He's concerned, after describing the area to him, that the water level would not be sustained at the ideal level. Because the creek is so much lower in elevation, he says the water level of the pond will likely be the same as the creek due to the soil vs. clay levels. Basically, you look at the conjoining bank of the creek and you can see where the clay hits the darker dirt. He says, when we dig, that will be where the water line stays. It'll leak out exactly where the clay meets the dirt. Anyway, if this is the case, and the water level will not rise above that, I should find out before we dig so we make sure that we do things correctly. I was thinking that, when we dig, and if we have to dig deeper than so be it, that we hold onto the clay we get out and spread it up the banks to seal it. Does that sound doable or have you heard of that before? 2 feet or slightly more deep should be enough right? Packed down pretty solid of course.

If you are catching runoff and holding it as it sounds you are discribing by sealing it off that is correct. On the other hand if you are digging a hole beside the creek and into it's water table your friend is correct it will rise and fall with the creek water level.

I threw this together really quick, but it gives you an idea of how the elevation is between the creek and the prospective pond. The clay looks to be about halfway up that 30 foot bank, give or take of course.

I have one of those with about a 15 foot difference. After a huge rain I traded out some redears and CNBG for some green sunfish and bullheads. That is the only time that forage pond has really been full.

My point is that you can never be 100% sure about what Mama Nature is going to do.

My property line is in the middle of the creek, so it wasn't possible for my pond to go there. I dug mine out next to the creek with a long dam around two sides of my pond. The creek flows year round, but the height changes quite a bit from the amount of rain we get. I put a drain into the bottom of my pond that goes into the creek. and is just a few inches above the water level of the creek. My pond is 12 feet deep when full, so my water level is 12 feet above the water level of the creek.

I had some concerns that the water would seep through the bottom of my pond and into the creek. While digging my pond, I was in clay the entire time except for one area that was sand. In that area, I dug out the sand extra deep and packed it with clay.

It might be that I was over every inch of my pond so many times with my dozer that I compacted it and sealed it from leaking, or it could be that the clay was already there and is working perfectly at holding water. I'm not knowledgeable enough to know for sure, just that my pond doesn't leak into the creek.

I have a yardstick stuck into the spillway that is covered up when my pond is full. I can look at it to see exactly how low it is when it's not full. I have a steady drop during the heat of summer, but when it's cooler out, there is no noticeably drop in the water level. This tells me that I'm losing water to evaporation, but not to a leak.

If there is clay, you can move it around to seal your pond. If you have to truck it in, then it gets very expensive. As for the layers, that should be easy enough to overcome with a good layer of clay to create a bowl inside of your hole in the ground.

Good luck,
Eddie

Good stuff Eddie. I think what I'll do till I get the 'dozer out there, is just take the skidloader and dig a hole down to see what kind of soil I'm dealing with to get a leg up and see what I'll be looking at down the line. Water does sit in spots where we'll be digging so I think that's a good sign, but I want to be thorough of course and make sure I get no leakage in the future. Very encouraging to see that someone has done what I was considering too.

If you have some time, here is the thread on my pond. I haven't looked at it to be sure, but I think there are some pics that show the creek and pond in there.

http://www.pondboss.com/forums/ubbthreads.php?ubb=showflat&Number=139488&fpart=1

Eddie

I'll definitely check that out Eddie. Thanks again.

Omaha
If it is possible fill the test holes you dig with water and see how well they hold.
Eddie MAKE his work.

Dave said it well it is hard to tell for sure what mother nature is going to do.

Otto

I plan on getting out there and digging a hole. It's far from the house so I can't add water manually, but it's supposed to rain this weekend so maybe I'll get lucky, dig a hole, and see what happens.

The creek is a good source of water. Just bring a bucket and see what happens when you add water to the hole. Watch it and see what it does. You really don't want to mess with test holes after it rains and the ground is muddy.

Good luck,
Eddie

Oh, so you guys are talking just a small hole? I thought I needed to get deep, deeper than a bucket of water would give me. Shouldn't I try to dig down till I hit clay or the depth that I plan on going with the 'dozer?

I would use my backhoe and dig out a pit in the four foot range and go down about 8 feet if it was me. I have a backhoe, so it works for me. I would do this many times, all over the area you plan on putting the pond. Look at the dirt that you dig up and see what it's made of.

If you have a post hole digger, go down as far as you can and do it all over the place.

Then dump water in the hole and watch it. A five gallon bucket will take quite a few trips to get enough water in the hole, but at least you will find out if it's holding water. Either way, it's important information.

Eddie

It sounds like a lot of work but, Eddie is right it will be worth the trouble.
Otto

I wasn't able to get out there this weekend since it rained a bit, but I asked a guy to drill some holes for me out there while he was out in the area so I'll run by there some time and see how they look.