Pond Boss Forums POND CONSTRUCTION Soil questions Blue bottom clay?

I am a newb who has never done anything like this before. I will be buying some property in South Carolina or Georgia this summer and am pre-planning some projects i am interested in, one being making a pond. I contacted a company about Bentonite Clay as i heard that is the alternative to a liner. They told me i'd be better off with Blue Bottom Clay. My questions are as follows:

1) Is Clay cheaper or more expensive than a liner? I was looking at approx a 25 x 35 pond, the liner was about $1500.

2) Is Blue bottom Clay the right choice?

3) Where would i buy some? Cant really find anything online. The source that turned me onto it said just ask at your local sand and gravel dealer.

4) How much clay would i need to apply? Ive seen everything from 4 inches to 2 feet (which seemed alot)?

Any advice would be greatly apreciated. tyvm!

Hello Doce.

I haven't heard of A product called "blue clay", but there is a bunch I don't know. Maybe Mike Otto or TJ will chime in with some words of wisdom.

Welcome to the forum and congrats on your place.

Cmm

I havent bought it yet (june) but tyvm!

You think the anticipation is bad now, wait until you are waiting and waiting for construction and filling of the pond. Then stocking, then growing big enough...
Ahh, it's great.
Cmm

Blue clay is a form of clay that to my limited knowledge occurs primarily in the glaciated portion of the US. It is dark grey-blue color, very dense, and compacts very well resulting in very low water seepage. My recommendation is to contact a soil scientist in your area either governmental or private for best clay liner material in your area. Local soil and water conservation district should know of a soil scientist in your district.

From the Web
Upper Glacial Till
The upper glacial till is commonly referred to as the blue clay due to its color. The glacial till was deposited during the aftermath of the last period of glacial advancement (approximately 10,000 years ago). The advancement of the glaciers from Canada stripped the soil and rock materials in the path of the glacier. The soils and rock material were mixed together in the advancing glacial. As the glacier melted this material was deposited. The glacial till material is
a relatively uniform clay material with occasional sand pockets, and cobbles and boulders. The sand pockets are limited in area and are not found to be interconnected. The upper till material is of a very low permeability, on the order of 1 X 10-8 cm/sec. In fact, this clay material is of such low permeability and consistent quality that it is used for construction of the landfill liner and cover systems. The low permeability of the material also retards water movement in this geologic unit. It should be noted that glacial tills do not have a layered or varved deposit. The upper till material is found at a depth of 20 feet below grade to a depth of approximately 60 feet (approximately 40 feet thick).

Lower Glacial Till
The lower glacial till is commonly referred to as the hard pan due to its very dense properties. The lower till is also a glacial till deposited during an earlier glacial period, approximately 25,000 years ago. The lower till consists of clay of an extremely low permeability, on the order of 1 X 10-8 cm/sec. The high density of the material is a result of over consolidation caused by the weight of the glaciers and overlying soils on this deposit. The lower till is sound at a depth of approximately 60 feet below grade to a depth of approximately 80 feet (approximately 20 feet thick).

Ty guys... Im thinking now that a liner is the cheaper alternative, whether its cheap or not... ty again!

Hi Doce,

Welcome to PBF!

FWIW I suggest, once you purchase the land, have a reputable pond builder dig a test hole at the site you want your pond. I am not a pro pond builder but IMO it is very possible that you will have clay at the site already that will be suitable for sealing the pond. Although blue clay is great, in my understanding, the clay does not have to be blue clay to work.

Again, Welcome to PBF!

Bill D.

Do your homework before spending money. Plastic or rubber liners are prone to puncturing and then leaking. Larger dogs crawling out of the pond have put holes in some pond liners.

Im an amateur,and will be on a budget, and also want to do most of the work myself. The liners i have looked up, and the pond professionals seem to think they will last forever and no need to fear of breaking. But they arent cheap. Being an amateur i had no idea how expensive clay would be or how much would be needed. Ive been reading alot of sites and watching alot of vids. Alot of people use liners, some on some huge ponds, wild ones too. I just thought clay would be a more permanent solution, but as i said ill be on a budget.

To get an idea of actually how good those liners are, ask them for how long it is warrantied in writing to not leak? What about punctures or tears from various unknown sources?

TJ might be able to help if you are on a budget and have a small pond. You could research your soil type and consider a strategy of digging the hole as you have time and funds. Depending on how much ground water seeps in the pond from the bottom you could treat with a polymer sealer to the level of the water at the completion of your dig. Then as it fills, add more granular sealant just above the water line, perhaps till it in the ground a bit on the edges as you go, then keep sealing at further distances around the perimeter as the water level comes up.

Probably more cost effective than hauling in clay or fussing with a liner. If it doesn't work you can always let the water go back down, or pump it down and then lay the liner later. By then you might decide you have different goals too. You may want a bigger pond, or a swimming pond, etc.

Ty for the help guys...

In regards to the liners some of the experts say they are guarenteed for basically 20 years, but thats primarily against damage from the sun, if they are under water they would / should last much longer.

Live stock and assorted animals can also damage a liner.

BTW, is your soil such that it won't hold water?

This is just the planning stages. I havent even bought the land yet. I'll be purchasing land in June. Im just planning so when the time comes i can get to work. Id prefer clay but until i get some idea of the costs, im thinking liner.

Doce,

With the right type of soil, and a good pond constructor, you may not need additional clay hauled in OR a liner installed. When you get the land, or before if possible, get the site tested for what type of dirt is there.

Cmm

Will do tyvm...

When looking for or at a particular parcel of land, and you are interested in building a pond, go talk to that counties USDA NRCS office. They can advise you on the soil type and how ponds typically are built in the area.

When building a pond, don't cut corners. Even if it takes an extra year or two to save enough $$ to build it, do it right the first time. If not, you will more than likely spend the same amount of $$$ all over again to fix a leaking pond.

I prefer a correctly compacted clay liner in a pond. Any renovations or changes can be done easily. With a liner, once it's installed, that's it. Liners are heavy, and take more than one or two people to install, and if the pond is large enough, the seams have to be glued together. If for some reason the liner starts to leak, if it's underwater it might be harder than a clay liner to fix.

Another option is talking to teehjaeh57 about Soilflock if the ground is marginal for sealing. Incorporate it into the soil before the pond fills with water.

Id prefer clay if its in my budget. Thx again!

Doce,

With a pond of approximately 900 square feet surface area, IMO there will be lots of options for sealing. How deep will the pond be and what is your goal for it? I am still a little bit confused as to why you think you will need to buy clay or a liner when it is very possible you will have "free" clay on the property you purchase. I would wait and see.

Good Luck

Im a newb, i have no idea what im doing which is why im doing so much research ahead of time. I had no idea about "free" clay tbh until people started mentioning it.

First off I am planning on moving to South Carolina or Georgia (with GA more likely atm). I was planning a pond based on the first piece of property i was looking at, however the dimenions are about what i want. Figure 35 x 25 with 3-4 feet deep. Nothing huge, but not a small ornamental pond.

Originally my plan was for a more "natural" pond, however i am considering making it more cosmetic possibly by adding lights, a waterfall, use a pondkit etc...Im open at this time, and it will depend on how i think it fits in whatever property i get. I'd really like to keep my costs low, not free, but i dont want to spend more than a few thousand if possible.

I am open and welcome all ideas and suggestions. TY again for all the replies guys!

Gleyed colors (grays, blues, greens) in clay are due to saturated conditions and generally due to a chemical reduction in iron (as opposed to oxidation of iron in well drained soils). The color of your clay is not likely as important as the clay content vs. the coarse fractions found in the material.

I echo sentiments here - NRCS contact they will know local soils, check neighbors ponds see if they leak, who built them, what did they find, etc. Then find reputable pond engineer, test holes, determine soil types and if you find clay, which you likely will, you can test it's plasticity to determine if you anticipate problems with sealing. Pond built with existing materials are cheapest and easiest. If you run into a snag following all this, trucking clay is an option, as is a liner, as is polymer. Cheapest is polymer, most reliable would likely be a liner, but I'd keep wildlife out of the pond for fear of punctures [fence] maybe?