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1toomanyhobbies
06-10-2011, 11:27 AM
I am interested in getting into building small, farm type ponds. I recently had a guy call me saying he already had a pond built by another guy but that it won't hold water. Because I am just starting I don't think that is the project to start with but it is a good point and I thought I'd throw out the question. If you build the pond and it just won't hold water then is the next thing to put in a pond liner? Do many people other than Chris have experience troubleshooting ponds?

mxridernorth
06-10-2011, 04:03 PM
You can seal it with a bentonite liner. There are various forms of bentonite products, depending on application method.

http://www.abcponds.com/ponds-information/how-sodium-bentonite-works.htm

hvy 1ton
06-10-2011, 04:25 PM
None of this is backed by any kind of scientific research, but what i've seen, experienced and been told by my betters. Reasons ponds leak most often:

1 Poorly installed overflow system. Either the pipe leaks below water line, water permeates the trench, or pipe leaks inside the dam and washes the pond. Check to make sure the overflow isn't running and there are no wet spots on the backside of the dam

2 Pond built in poor soils or location. Some soils are really bad at holding water and some locations are even worse, like building one 100' away from a creek or another pond. If you hate your neighbor build a pond downhill of him. Pond liners help with this. Easier to do from the beginning though.

3 Pond dam was poorly compacted or contains permeable soils. my favorite being the dam that was built without removing the topsoil. When we dug it up there was still grass. Famliy friend that does all our big conservation work is big into fixing leaking dams. He has a soil mixer for one of his excavators like this (http://www.youtube.com/watch?v=1b8-zTarWlQ). He'll core the dam and over flow and then backfill mixing in bentonite and compacting the **** out of it.

1toomanyhobbies
06-10-2011, 05:25 PM
Excellent information. After posting this I started doing some research and have been looking into sodium bentonite. I ended up calling the customer back and referring him to Chris but because of the distance from Raleigh and limited budget, we kept talking and he ended up wanting to work with me because i was at least honest in telling him I wasn't an expert. If I can just make cost on the work i do, the learning opportunity will be well worth it for me. I think building ponds/dredging is some what of a niche market and if i can learn how to troubleshoot/fix leaks then it will really help me differentiate myself going forward.

The customer does think he may have problems with his drain pipes and mentioned putting in a seep collar. Ill have to take a look tomorrow and see if i can see any wet spots on the back side of the dam.

hvy 1ton
06-10-2011, 07:42 PM
So the overflow doesn't run unless the water is above the inlet?

1toomanyhobbies
06-10-2011, 08:16 PM
I don't know. We covered so many different options on the phone I can't remember what he said. I report back tomorrow after I see it in person.

hvy 1ton
06-10-2011, 09:30 PM
I don't know. We covered so many different options on the phone I can't remember what he said. I report back tomorrow after I see it in person.

Definitely rule that out first. I have that problem talking on the phone too. I do better in person.

1toomanyhobbies
06-11-2011, 09:31 PM
I went there today with a family friend who has 25 years of experience and has been a mentor to me. Thank God for mentors. He nailed the problem as soon as we got there. The soil was red clay with a lot of small rocks in it. My friend said it would probably pass for use in a septic field. We talked to the guy about bringing clay in verse sodium bentonite. The farmer is trying to do this as cheap as he can so we are going to look at the cost putting in 6 inches of heavy/dense clay with a lighter layer of sodium bentonite on top verse just putting in a heavier coat of sodium bentonite on the soil he has now. With all the rocks in the current soil we are going to try and push for having good clay brought in.

hvy 1ton
06-11-2011, 10:57 PM
If you knew it was only leaking through the dam, coring it and replacing with low permeability clay would fix it. If the whole pond is leaking like a sieve it gonna need some kind of liner. I don't know anything about lining ponds with bentonite, but I've worked around PE liners for dairy lagoons and they're a pain.

Dirtman2007
06-11-2011, 11:48 PM
I went there today with a family friend who has 25 years of experience and has been a mentor to me. Thank God for mentors. He nailed the problem as soon as we got there. The soil was red clay with a lot of small rocks in it. My friend said it would probably pass for use in a septic field. We talked to the guy about bringing clay in verse sodium bentonite. The farmer is trying to do this as cheap as he can so we are going to look at the cost putting in 6 inches of heavy/dense clay with a lighter layer of sodium bentonite on top verse just putting in a heavier coat of sodium bentonite on the soil he has now. With all the rocks in the current soil we are going to try and push for having good clay brought in.


I love bentonite, I put out 10,000 lbs of it into a pond once. it was the powered stuff and man what a mess it made. I hate to say it but I don't think the pond held water much better after that:hammerhead:

AWJ Services
06-12-2011, 11:37 AM
Soil consists of 3 basic sizes. Sand silt and clay. Sand is the largest and clay is the smallest.

People tend to call everything clay except sand. Moisten the soil and try to roll into a worm between your hands. The more easily it rolls into a worm the more clay it has.

Compaction or lack of determines the soils permeability. The smaller the soil particles the more easily it is to compact. once you compact the soils structure you lower it's permeability greatly.

Soil has 3 basic horizons. A,B,C . A is topsoil, B is usually dirt composed of the 3 soils and then C is your parent material( like bedrock or saprolite).

If the pond is build on the c horizon and the horizon contains saprolite the soil is very porous.Saprolite is weathered rock. Some people call it sandstone.

Usually when the pond is filled there will be silt or clay washed into the pond bottom which usually will help seal the porous soil helping it retain water. Thats the very creamy soil you often see left in a mud puddle when it starts to dry.

Here when building a pond you want the bottom to have a good layer of compacted clay ( or hard pan as the old timers call it) on the bottom.

One other thing is they may have built the dam from the incorrect dirt. here we dig down to good clay and then use that to build the dam.
Some people just start pushing the soil from the pond onto the dam. When the pond is done the dam is done.

1toomanyhobbies
06-12-2011, 11:47 AM
I love bentonite, I put out 10,000 lbs of it into a pond once. it was the powered stuff and man what a mess it made. I hate to say it but I don't think the pond held water much better after that:hammerhead:

Hi Chris. From what I have seen it looks like 2 pounds per square foot is the norm/minimum to use. Was the pond 5000 square feet? It seems like you don't have much faith in using sodium bentonite. Do you have any other recommendations if the won't hold water?

1toomanyhobbies
06-12-2011, 12:08 PM
Soil consists of 3 basic sizes. Sand silt and clay. Sand is the largest and clay is the smallest.

People tend to call everything clay except sand. Moisten the soil and try to roll into a worm between your hands. The more easily it rolls into a worm the more clay it has.

Compaction or lack of determines the soils permeability. The smaller the soil particles the more easily it is to compact. once you compact the soils structure you lower it's permeability greatly.

Soil has 3 basic horizons. A,B,C . A is topsoil, B is usually dirt composed of the 3 soils and then C is your parent material( like bedrock or saprolite).

If the pond is build on the c horizon and the horizon contains saprolite the soil is very porous.Saprolite is weathered rock. Some people call it sandstone.

Usually when the pond is filled there will be silt or clay washed into the pond bottom which usually will help seal the porous soil helping it retain water. Thats the very creamy soil you often see left in a mud puddle when it starts to dry.

Here when building a pond you want the bottom to have a good layer of compacted clay ( or hard pan as the old timers call it) on the bottom.

One other thing is they may have built the dam from the incorrect dirt. here we dig down to good clay and then use that to build the dam.
Some people just start pushing the soil from the pond onto the dam. When the pond is done the dam is done.

my friend tried to roll the clay into what he called a ribbon which i think is similar to your worm. If I understand what he said about the test is if you can make 1 inch of ribbion it isn't suitable for septic systems because of poor drainage. When he tried that with the wet soil at the pond he wasn't even able to get 1/2 an inch. If I understand correctly that means the soil will drain.

AWJ Services
06-12-2011, 02:11 PM
It is a very rudimentry test but is helpful.
Remember they have lakes in very sandy soils so to just to blindly blame it on the soil is not wise.

How much water is coming into the pond?
What is the surface area?

The evaporation rate can be pretty large this time of year.

1toomanyhobbies
06-12-2011, 02:46 PM
You do make a good point about making assumptions. I have read where you can take a 5 gallon bucket and drill holes througout the bottom and put 3 inches of the dirt and then 2 gallons of water. If it doesn't hold then the soil isn't suitable for a pond. I think I'd like to test the soil at the pond and also test the clay that will be brought in.

The pond is only fed by run off but is at the bottom of a very large hill and basically all of one side drains into this pond. The pond is about 200' by 200' and about 15' deep to the top of the dam but only has 6 inches of water in it right now. It does have a pvc bottom drain that we plan to use for draining the pond when putting in the liner.

There is no water coming out of the drain so we don't think it is leaking. There is a wet spot 35 yards below the dam at a slightly lower elevation which is another reason we think water is seeping through the soil.

AWJ Services
06-12-2011, 06:13 PM
No bigger than that is I would just do a rubber liner. lol

That pond could very well lose a couple inches a day to evaporation. Without a water source he is fighting a losing battle. here those type ponds have water in them about 65% of the year. From May till september they just go down and down due to the lack of rainfall. My lake at my house has a very small creek going into it that dries up in the summer. From that point on it usually losses up to 4 feet or more when we where in the drought. It was one of the few ponds around here that kept water in it.

1toomanyhobbies
06-16-2011, 10:57 PM
I did some more research today so I could call the customer back with some numbers. Holy cow is sodium bentonite expensive. The lowest recommendation I could find is 1 pound per square foot. 200x200 is 40000 square feet which is 40k pounds of bentonite. A pallet is 2400 pounds and cost 672 before shipping. Hmm, 11.2k before shipping just for the bare minimum. My friend is able to bring in 14 yard tandem loads for $100 per load. It looks like it will take 52 loads to get 6 inches of clay brought in but that is still much cheaper than the sodium bentonite. I recommended to the customer we try just 6 inches of clay first and pack it down and see how that goes as phase one. If it holds water then no reason to add more cost.

I did talk to him about the fact that his only water comes from rain and that he is losing water to evaporation. Because we did see a wet spot below 25 yards below the dam, I do think it is leaking some so i do think adding the clay will help with the retention but again, it will be a matter of amount of water add from rain vs amount of evaporation between showers.

Dirtman2007
06-16-2011, 11:17 PM
I did some more research today so I could call the customer back with some numbers. Holy cow is sodium bentonite expensive. The lowest recommendation I could find is 1 pound per square foot. 200x200 is 40000 square feet which is 40k pounds of bentonite. A pallet is 2400 pounds and cost 672 before shipping. Hmm, 11.2k before shipping just for the bare minimum. My friend is able to bring in 14 yard tandem loads for $100 per load. It looks like it will take 52 loads to get 6 inches of clay brought in but that is still much cheaper than the sodium bentonite. I recommended to the customer we try just 6 inches of clay first and pack it down and see how that goes as phase one. If it holds water then no reason to add more cost.

I did talk to him about the fact that his only water comes from rain and that he is losing water to evaporation. Because we did see a wet spot below 25 yards below the dam, I do think it is leaking some so i do think adding the clay will help with the retention but again, it will be a matter of amount of water add from rain vs amount of evaporation between showers.

I've never tried this before but what do you think about getting a big roll of plastic like they use under houses, you can get like a 100x100 roll for a 100 bucks I think? lay that down then cover with dirt and try not to tear into it?

1toomanyhobbies
06-16-2011, 11:29 PM
That sounds like a good idea. is this something I can pick up a Lowes/Home Depot? i don't think I have seen it before.

Dirtman2007
06-16-2011, 11:31 PM
That sounds like a good idea. is this something I can pick up a Lowes/Home Depot? i don't think I have seen it before.

yeah its used under houses as a vapor barrior. i dont see what it would hurt.

1toomanyhobbies
06-16-2011, 11:49 PM
Thanks Chris, I will definitely use that. Right now the dam is pretty steep so i think i will put it on the dam and hopefully it will also cover the deep area too. I remember reading that after a certain number of feet of water, the pressure increases so I think that would be the area the pastic liner would benefit the most.

bobcatexc
06-18-2011, 12:29 AM
Good Idea Chris, but I think the dirt when wet will slide down the plastic liner.

Dirtman2007
06-18-2011, 12:54 PM
Good Idea Chris, but I think the dirt when wet will slide down the plastic liner.

Yeah didn't think about that but I'd be good for the bottom as long as there was little slope. It'd prolly turn to a liquid mess being only 6 inches but that will seal and leaks if there are any in the bottom
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1toomanyhobbies
06-19-2011, 11:46 PM
I had the guy try the 5 gallon bucket test this weekend with 6 inches of his dirt. he tamped it down to around 5 inches and said it was leaking out the bottom in less than 4 hours. He is out of town this week but we have setup for this coming Saturday to do the test with the clay we will be hauling in. I am hoping once he sees the difference we will be able to get started. As you can tell I am looking forward to this project. :)

1toomanyhobbies
06-27-2011, 10:51 PM
So I'm pretty frustrated right now. I had done a lot of research for the customer on this project. I had kept the customer up to date along the way. We discussed the price of sodium bentonite vs clay. Clay was cheaper so he wanted to go that route. I suggest the bucket test to prove his soil didn't hold water and that the clay we wanted to use would work. He raved about this because it was an unbiased test and complimented me on how he thought I was giving the best advice/recommendations of anyone he has spoken to. I got my friend to find some really good clay that again the customer was very happy about and agreed it would do the job.

I start talking about how we would want a couple of days for the my friend to bring in the clay before I come with the skid steer to start spreading. Well then come the excuses. I was amused at some that he used. 1) that the dump truck should be able to use the spreader gate to spread the clay, 2) that the dump truck should be used to pack the clay (in a drained pond mind you) and that using a vibrating packer is wasted money even though on the first day we met he told ME he listed that as a requirement 3) And the best is that with all the recent rain he thinks the pond is now holding water even though he told me last week that when tested in the bucket it didn't.

He wants me to do more research with him to understand how now suddenly the pond is holding water. I told him i couldn't invest more time in the project without some commitment on work and then started talking about how he doesn't feel I have enough experience for the project...even though a week ago he was given me compliements and my friend has 20 years of experience. *sigh* Oh well, I know this is part of the deal that people want work to be done but when it comes to actually commiting and spending money then suddenly everything changes. I was really looking forward to the project and we really had found a solution that would resolve the issue. My friend was going to bring in tandem loads for $100 (dirt and delivery) and I was charging $65 an hour for skidsteer. I thought that was a pretty good deal for the guy.

It is what it is, its just hard to realize all the time I spent has gone down the drain plus the time of my friend who checked several places for the best source of clay. Ok, Ill stop complaining now.

Dirtman2007
06-27-2011, 11:22 PM
So I'm pretty frustrated right now. I had done a lot of research for the customer on this project. I had kept the customer up to date along the way. We discussed the price of sodium bentonite vs clay. Clay was cheaper so he wanted to go that route. I suggest the bucket test to prove his soil didn't hold water and that the clay we wanted to use would work. He raved about this because it was an unbiased test and complimented me on how he thought I was giving the best advice/recommendations of anyone he has spoken to. I got my friend to find some really good clay that again the customer was very happy about and agreed it would do the job.

I start talking about how we would want a couple of days for the my friend to bring in the clay before I come with the skid steer to start spreading. Well then come the excuses. I was amused at some that he used. 1) that the dump truck should be able to use the spreader gate to spread the clay, 2) that the dump truck should be used to pack the clay (in a drained pond mind you) and that using a vibrating packer is wasted money even though on the first day we met he told ME he listed that as a requirement 3) And the best is that with all the recent rain he thinks the pond is now holding water even though he told me last week that when tested in the bucket it didn't.

He wants me to do more research with him to understand how now suddenly the pond is holding water. I told him i couldn't invest more time in the project without some commitment on work and then started talking about how he doesn't feel I have enough experience for the project...even though a week ago he was given me compliements and my friend has 20 years of experience. *sigh* Oh well, I know this is part of the deal that people want work to be done but when it comes to actually commiting and spending money then suddenly everything changes. I was really looking forward to the project and we really had found a solution that would resolve the issue. My friend was going to bring in tandem loads for $100 (dirt and delivery) and I was charging $65 an hour for skidsteer. I thought that was a pretty good deal for the guy.

It is what it is, its just hard to realize all the time I spent has gone down the drain plus the time of my friend who checked several places for the best source of clay. Ok, Ill stop complaining now.



Gotta love it.

I landed a job yesterday fixing a leaking pond. we agreed on recoring the leaking pond dam with clay and mixing 2000lbs of bentonite with the dirt as we pack it in

FLAhaulboy
06-27-2011, 11:47 PM
Dirtman,

Can I ask you how much time you spent researching this issue & talking with the owner? Thanks.