Pond Boss
Posted By: The Greer Proper Soil Compaction - 12/15/14 05:48 PM
I will soon have a 1/2 acre pond constructed in Hunt County Texas. The native soil is clay.

I am curious to know what soil compaction technique I should expect from my contractor?

When I speak to a contractor, i want to have a little knowledge about this so I don't make a mistake and end up with a leaky pond. All info is greatly welcomed!
Posted By: Bill D. Re: Proper Soil Compaction - 12/16/14 01:41 AM
Hey Greer,

I am not an expert, so I will not offer advice, but I have seen many inputs here at PBF on soil compaction. If nobody jumps in with your answer, I would google "clay soil compaction pond boss." You should get lots of info.

Good luck with that new project!

Bill
Posted By: liquidsquid Re: Proper Soil Compaction - 12/16/14 02:03 AM
Also search for "Sheeps foot roller" or in absence of availability, a fully loaded loader or some such with 6 inch lifts.
Posted By: Dave Davidson1 Re: Proper Soil Compaction - 12/16/14 03:04 AM
The Squid pretty well nailed it there. The sheepsfoot is something that a lot of dozer drivers/soil packers do poorly.
Posted By: esshup Re: Proper Soil Compaction - 12/16/14 05:04 AM
You should be working with cohesive soils when building a pond. Here is some reading that might offer some hints and tips:
http://www.iowadot.gov/erl/archives/Apr_2004/CM/content/6-40.htm
Posted By: george1 Re: Proper Soil Compaction - 12/16/14 12:00 PM
Greer, all good advice above.
What part of Hunt County are you located?
If you are in the northen part of county you may have expansive "black gumbo" clay - I am aware of a couple of leaky ponds in those areas.

But if you are south, your soils may be similar to our Delta County soils and have good clay and sandy clay.
I am not aware of any leaky ponds in our area.
Talk to your neighbors that have ponds and get info on local pond builders.

I have never seen a sheep's foot roller used in our area, but it was interesting to watch our pond guy with a double "scraper" picking up clay with one and sandy clay with the other, spreading and mixing on the dam and each time being compacted with a large dozer.
Never a hint of a leak in our 12 year old ponds.

We lost him a few years ago - not only the best pond builder around, but a friend and a neighbor as well.

Good luck on your pond adventure.
George Glazener
Posted By: playsomehonk Re: Proper Soil Compaction - 12/16/14 08:04 PM
Greer,

Last summer I completed a 5 acre pond in an area with marginal soil, ie mostly clay but with some significant sand strata, I am not a pond expert by any means. Thankfully and I believe due to many precautions and good practices (including some my contractor argued against, like a vibratory roller), my pond is currently holding water as good as if it were lined with a synthetic liner. I am an industrial contractor with 30+ yrs of experience, including soils and geotechnical work, and I applied the practices I've learned to compacting and manipulating soil for my pond, ie making dirt hurt:-)

Here are a few items you may want to consider:

First you must have enough good clay soil on your site to manipulate over any suspect (sand, silt) areas. If your site is totally clay with good impermiablity, then you may not need to compact much if at all if its an excavated pond with no dam. If the pond is excavated and will not include a dam, its a straightforward effort. Any excavated areas not containing clay need to be cored and/or capped with good clay and 24" is a commonly recommended thickness for capping/coring.

Clay capping should be done in ~8" lifts (layers) and compacted with a vibratory pad foot roller ideally. An 8" lift of loose clay will compact to a ~6" compacted layer. Make sure the clay isnt too wet or it will "pump" and never compact.

If your pond is an embankment pond, the dam must be cored into good clay. A deeper core trench is generally better than a shallower core trench, but the most important thing is to tie in to good clay. From the bottom of the core trench, start spreading the 8" layers of good clay with the proper moisture content and compact each one with the roller. When properly compacted the roller "walks out", which means the pads do not sink down very deep at all into the compacted soil. A good rule of thumb is to at least roll over the lifts 5-6 times. If the clay will not compact after 10 rolls or so, it may be too moist. Do not place lifts over other lifts that are not properly compacted and/or contain too much moisture.

The entire dam is built using this process. I know this is overly general but hope it helps. Most would agree that a dozer will not produce adequate compaction. A scraper pan can compact better than a dozer if used correctly, but not as good as a vibratory roller.

Best of luck and let me know if you have any questions about the above.
Posted By: esshup Re: Proper Soil Compaction - 12/17/14 01:09 AM
Simple, but very easy to comprehend. Good answer!!
Posted By: The Greer Re: Proper Soil Compaction - 12/17/14 03:15 AM
Thanks for all the comments.

Originally Posted By: george1
Greer, all good advice above.
What part of Hunt County are you located?
George Glazener


I'm near Greenville and Commerce. Do you know if this area has good soil? I know there is a significant amount of dark clay on the top. After seeing some digging done deep down it's much more tan color but still very much clay.

All of the contractors I've talked to so far say the same thing that for farm ponds they don't need compaction.
Posted By: The Greer Re: Proper Soil Compaction - 12/17/14 03:20 AM
Originally Posted By: playsomehonk
Greer,

Last summer I completed a 5 acre pond in an area with marginal soil, ie mostly clay but with some significant sand strata, I am not a pond expert by any means. Thankfully and I believe due to many precautions and good practices (including some my contractor argued against, like a vibratory roller), my pond is currently holding water as good as if it were lined with a synthetic liner. I am an industrial contractor with 30+ yrs of experience, including soils and geotechnical work, and I applied the practices I've learned to compacting and manipulating soil for my pond, ie making dirt hurt:-)

Here are a few items you may want to consider:

First you must have enough good clay soil on your site to manipulate over any suspect (sand, silt) areas. If your site is totally clay with good impermiablity, then you may not need to compact much if at all if its an excavated pond with no dam. If the pond is excavated and will not include a dam, its a straightforward effort. Any excavated areas not containing clay need to be cored and/or capped with good clay and 24" is a commonly recommended thickness for capping/coring.

Clay capping should be done in ~8" lifts (layers) and compacted with a vibratory pad foot roller ideally. An 8" lift of loose clay will compact to a ~6" compacted layer. Make sure the clay isnt too wet or it will "pump" and never compact.

If your pond is an embankment pond, the dam must be cored into good clay. A deeper core trench is generally better than a shallower core trench, but the most important thing is to tie in to good clay. From the bottom of the core trench, start spreading the 8" layers of good clay with the proper moisture content and compact each one with the roller. When properly compacted the roller "walks out", which means the pads do not sink down very deep at all into the compacted soil. A good rule of thumb is to at least roll over the lifts 5-6 times. If the clay will not compact after 10 rolls or so, it may be too moist. Do not place lifts over other lifts that are not properly compacted and/or contain too much moisture.

The entire dam is built using this process. I know this is overly general but hope it helps. Most would agree that a dozer will not produce adequate compaction. A scraper pan can compact better than a dozer if used correctly, but not as good as a vibratory roller.

Best of luck and let me know if you have any questions about the above.



Thanks for all the detailed info. Half of my pond will have a dam because the area we want is basically sloping downward and continues on. So we're going to catch it and hold it.

Unfortunately, due to my experience working with contractors in the area on past projects, I can say for certain that I'm not going to find anyone with attention to detail and knowledge that you have.

All the contractors say they don't do compaction. Probably they don't have the equipment and if they did wouldn't know how to use it.

Since I have good soil (everyone in the area has told me that), could I maybe hire one of these dozer guys to dig the pond and put in the dam and then hire someone else to come do the compaction?
Posted By: Dave Davidson1 Re: Proper Soil Compaction - 12/17/14 09:36 AM
Not compacting means, to me, that you haven't talked to the right dozer driver yet.
Posted By: george1 Re: Proper Soil Compaction - 12/17/14 01:58 PM
Originally Posted By: The Greer
Thanks for all the comments.

Originally Posted By: george1
Greer, all good advice above.
What part of Hunt County are you located?
George Glazener


I'm near Greenville and Commerce. Do you know if this area has good soil? I know there is a significant amount of dark clay on the top. After seeing some digging done deep down it's much more tan color but still very much clay.

All of the contractors I've talked to so far say the same thing that for farm ponds they don't need compaction.

Greer, I am very familiar with your area – I travel from Plano to my son’s place near Cooper – travelling between Greenville and Commerce.
Almost every piece of property that I see on this route has dug stock tanks for cattle, and no managed ponds. – I will look closer next trip.

Are you generally north or south of the highway – flat backland wheat country to the north or rolling hill county and trees to the south?

If your property lies to the north in the flat wheat country with black gumbo clay soils , the pond builders you have spoken with are correct in saying no compaction is necessary - if just a hole is dug in the ground. This is what I mostly see on this route.
If a dam is required those dark clays cause problems due to contraction and expansion, and I would be leery of their advice.

If your property is to the south of highway with trees with clay and sand, these are some of the best dam building dirt around but needs some compaction.
I am not aware of any leaking ponds in this area.

The geology in this area is interesting . My son’s place is located in the Cretaceous/Tertiary geologic outcrop area with lots of trees with with a small creek – a quarter mile to the north, it is flat land with wheat fields growing in black dirt!

A Google Earth image would be helpful to provide additional information – you can crop the coordinates from the image to maintain confidentiality.
Also a topographic image of property would be helpful – others on the forum will will able to contribute – lots of helpful talent on this forum.
Good luck,
George Glazener
Posted By: playsomehonk Re: Proper Soil Compaction - 12/17/14 04:47 PM
Greer,

I used what I believe was the best pond builder in SW Missippi and he had never used a vibratory roller before and argued with me when I wanted to use one. I asked him to rent one and I'd pay for the 3rd party rental, so we agreed on that basis.

The majority of the time, I drove the compactor (my wife also drove it!, so anyone can do it with a little instruction) so I could see it "walking out" and also see what type of soil the dozer was spreading in the lifts. Now the contractor is sold on a roller. From Nov 18 to December 15 I did not get a drop of rain and my pond level only dropped .24' (under 3"). This is likely mostly due to evaporation, so I see this relatively small amount of associated cost for the roller well worth it.

Honestly, with the sand strata that was encountered during the core tests and during excavation, I couldn't imagine it holding water this well.

Hope this helps.
Posted By: Bill Cody Re: Proper Soil Compaction - 12/17/14 09:30 PM
Your testimony shows how important it is to use the best compaction possible when building a pond. Proper soil compaction is a very big part of "building" a pond. Evidently some of the best pond builders still do not fully understand the roll of soil compaction for building low leak ponds. What does that say about the average or even good pond builders? Best is not always the best. As usual 'it all depends'.

""..he had never used a vibratory roller before and argued with me when I wanted to use one. I asked him to rent one and I'd pay for the 3rd party rental, so we agreed on that basis."" Your decision to go to the extra effort for getting the vibratory compactor was your insurance for minimal leakage. Very smart decision. When I rebuild any of my ponds I will insist on a vibratory compactor. I have seen first hand the benefit of using that machine. A well sealed local pond was built using a vibratory compactor and our local "best" pond builder and construction company said a good pond could not be built in that location. That construction employee even used to work for the Soil & Water Conservation District as a pond designer!.
Posted By: ThomasTponds Re: Proper Soil Compaction - 12/18/14 08:55 PM
Soil quality matters most when compacting for seal. A sheepsfoot roller adds to costs to a degree that may not warrant its inclusion.

If the site has native clay such as del rio etc, it can be pressed and installed using the right track loader, that was used to dif the hole in the first place, and save you money with strong reliability.

The best Pond specialist know soils, chemistry, native plants, AND equipment operations.

ThomasTponds.com
Posted By: Bill Cody Re: Proper Soil Compaction - 12/19/14 12:05 AM
When building a pond designed to best hold water, why would compacting the soil too much be a bad thing?. IMO the extra cost of using a proper equipment or the best soil compactor is similar to pond insurance. Not always necessary, but great to have when it is needed plus it adds an extra amount of soil sealing ability/'structure' especially in a small marginal area of unnoticed, inconspicuous, poor soil composition is present that could easily be the main source of a leak.
Posted By: playsomehonk Re: Proper Soil Compaction - 12/20/14 07:37 PM
TTP, I would agree that there may be some breakeven point where a roller may/may not provide a positive ROI. Every pond is different, but here are a few data points to consider.

Tracked equipment, ie dozers, are obviously made to "float" on soft soil and not sink, so the track bearing pressure (psi) is very low, like around 6 to 9 psi. Ground bearing pressure for rubber tired equipment can be in the 25-35 psi range and usually roughly equals the internal tire pressure. The pad foot roller I used exerted around 70 psi. I'm hesitant to quote these types of numbers on a public forum and I'm sure anyone can come up with values that differ from these, but the point is that a tracked piece of equipment exerts much less bearing pressure than rubber tired equipment, and much much less than most roller compactors.

My pond cost me in the $60K range and the roller cost $4K for a month rental. The $4K isnt the net addition I paid because if the roller wouldn't have been compacting the lifts, I would have paid for the scraper pan or other piece of equipment to compact. Large tractors with scrapers are expensive ($200/hr range) and I believe I even saved money using a compactor vs. a tractor and scraper pan, which is what my contractor originally wanted to use.

In summary, although there may be scenarios where a roller doesnt provide a positive ROI, I would never use a piece a tracked equipment to compact soil for a pond. A loaded dump truck is another consideration and if its a smaller pond, there are walk behind rollers and other types of inexpensive compactors as well.
Posted By: Bill Cody Re: Proper Soil Compaction - 12/21/14 08:34 PM
playsomehonk - this is great information for people wanting to build a pond. Thanks for sharing your knowledge and experience.
Posted By: Dave Davidson1 Re: Proper Soil Compaction - 12/22/14 01:13 PM
As usual, it all depends.
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