Hi Everybody!

I'll jump right in: I have a little farm with a tiny irrigation retention pond, and want to put a bigger pond in. I have the site planned out. The water will be from runoff and irrigation water.

The soil on my property is mapped as Outlook Sandy Loam, but when we did a test, we encountered a compact layer that was waterproof. The soil above the layer was all wet, but when we hit the layer 4' down, the layer was just moist in the top couple of inches, then dry down about 10 more inches. We did not go further, so I am not sure how thick the layer is.

I had the layer checked, and it is "Texture Silt Loam - Clay=10%, Silt=53%, Sand=37%", with some small rocks mixed in.

Does this sound like a good enough mixture of grades, for sealing by compaction? My intention was to have this layer saved, and dig for donar material if needed.

I want to have depths up to 12', so I figured if the above soil mix was good enough, I would line the bottom of the pond with it, disc it, then compact an 8" layer, then compact another 8" layer over that; doing all of the compacting with a sheepsfoot roller.

Any advice would be greatly appreciated. I also have illustrations of my plans, if anyone would like to see them!

Thanks in advance, Chris.

Welcome to the forum FarmPond!

I'm not your guy for soil questions, but there are plenty on here who know their stuff. Hang tight and I am sure your questions will be answered soon!

Best of luck in your project!

Add yourself to the Pond Boss Map while your here.

Welcome FarmPond:
You came to the right place. You will be fishing in your own pond, and the great guys here will help you with any question or problems that come up. You would not believe how much help I have received trying to restore a 10 acre lake (thought it was a lake but it is a spring fed/storm drain rain water detention pond, sold as a lake).
There is a magazine that is super cool on all things ponds, hope you get it. This is a family and you are in it now.

FarmPond:

Let me pass on a seat-of-the-pant soil test. Take a handfull of the moist layer you are questioning. Does it form into a firm ball when squeezed, or fall apart afterwards? Let it dry out for 2-3 days, then drop it on the floor. Does it bust apart or stay together? The better the soil stays in a ball during these checks, the more suitable it should be for pond dam/bottom use.

Whether speading an 8" layer then compacting is appropriate depends on the size of the compacter. We used a large (4 cylinder turbo diesel) vibrating sheepsfoot roller on my last pond, and built the core of the dam in 4"-5" lifts (dozered that much clay into place, then compacted it). So unless you are going to use a very large sheepsfoot, you may want to make the lifts thinner than 8".

You took your test hole about 5' down?

P.S. I would recommend the book "Perfect Pond: Want One?" for any would be pond owner, but especially for anyone who is contemplating the DIY approach.

Thanks for the welcome, guys!

Theo, I will try the balling the soil tests you described; I'm not at my property right now, but should get it done next week. Also, we tested to about 5 feet, because we were having a tuff time getting the core sampler deeper into the layer. On my neighbors property, several hundered feet away, the layer was about 10"-12" thick, however we were into the layer 12", and it continued, so it is prob. a bit thicker in this spot.

Also, thanks for the book recommendation! I'll get it, and I will plan on thinner lifts, instead of 8". And anything else the book or this site recommends, to make my pond succeed!

Thanks, Chris.

FarmPond
Welcome to the fourm. You are going to love this place.

The field test Theo told you about is about the best thing you can do.

You said you had the layer tested and had some % of clay, silt and sand who did the test and what did they say about it holding water.

Otto

Wow, when I read this sentence I wasn't sure if I wanted to read the rest of Theo's post. Fortunately the rest of the post had nothing to do with what I thought it would be about.

...don't forget the detailed procedures

Don't try this at home, kids.

Aaaaaww! You had to go there!

Otto, the test was done by a local soil testing place that specializes in testing fields for farmers, for suitability for growing certain plants. This is all they gave me. Suppose I'll have to check with another lab to get info on holding water.


I am now patiently awaiting my Perfect Pond book to arrive!

My pic didn't seem to want to work, so here is the link:

http://farm4.static.flickr.com/3361/3426892542_b770c2b356.jpg?v=0

Hey FarmPond
Here's another quickie field test, and it won't require a squirt of SHOUT.
Grab a small handful of the soil from below grade where it is still cool and damp. Work it in one hand, using your fingers to pinch out a narrow flat ribbon between your thumb and forefinger. The goal is to get a continuous ribbon to peel away without breaking off. It will curl downward a bit; that's OK, but we want it projecting somewhat horizontal so gravity comes into play.
If you can get a continuous ribbon about 3" long, you're clay content is likely darn good.

Another way. Mix up some of the soil. Put it in a bucket with a hole in the bottom. Tamp it down and add water. See what happens.

Or, get Otto to come to your site. Mix some of the soil with water into a ball. Throw it against the side of his pickup and see if it sticks or disintegrates.

Thanks for tweaking the image line, Theo!

Thanks for the suggestions, Dave. I did read about the bucket test before, and was going to give that one a try!

Checked with the soil firm this morning, and they do permeability tests (if that's what Otto is talking about). I can give them samples this coming week, after I make little balls and ribbons, and throw them at passing vehicles, dogs, and noisy children!

DISCLAIMER: No children or dogs have been, or will be harmed. The above statement was made in jest, unless of course you drive up my driveway un-invited. Then I might see if a mud ball sticks!

Well, didn't have as much time as I had hoped, but this is what I accomplished:

My neighbor and I dug a hole down to the clay/silt layer. We pounded a pipe into the clay layer, and filled the pipe with water. I checked it for 30 minutes, but the water did not drop. When I came back an hour and 40 minutes later, enough water had drained into the hole around the pipe, from the sandy loam, to cover the pipe.


The sandy loam above it is so saturated with water, that it quivers like jello. Before pounding the pipe in, we dug a small pile of the clay mix out, and squeezed it out between our fingers, and were able to get ribbons that went about 3-4 inches before breaking off. We also made balls out of it, and dropped them from a height of 3 feet, onto the bucket of the tractor. The clay balls stayed together, but the ball of sandy loam broke apart.



I let one of the smaller clay balls dry for a couple of days, and when I dropped it from about 3.5 feet, onto the concrete, it broke apart.


Then, I put some of the clay/silt into the bottom of a small container I had perforated, and put water in over it. I took a picture at 1450 hrs, and again at 1550 hrs. Some water had seeped out, with a little bit of silt, but not much.



I checked it again at 1645 hrs, and a little more water had seeped out, but hardly any at all. I picked up the container, and looked at the bottom side. There were small blobs of clay/silt sticking out of, and plugging, the holes.

I am going to redo this test with a bucket, and larger amount of clay and water.

My Perfect Pond book was also delivered to my pond site, so I am looking forward to getting back over there to do the above test again, and read my book!

welcome to the site. Where in WA are you?

Thanks, RB.

My soon-to-be pond is south of Moses Lake. I'm usually there every week, but my family has been having some medical issues, so I have been spending more time in the Oly area.

In regards to my soil, I've decided to do some testing to see how much bentonite I need to add, to get a good pond bottom.

I'm going to start with adding a pound of bentonite to a square foot of my soil, and testing with the leaky bucket. And I will work up from there. I'll let you guys know my results after this week (hopefully!).

Let us know what you do and what the results are. it will help us all