Natural swimming pond

So I dug a giant hole and lined it with bentonite and rock several years ago. Didn't use enough bentonite, pond leaked. Doesn't that figure. So then I had put rock all over it and had to take all of the rock off in order to add more bentonite. That has taken about 3 years. Ok 4 years. I feel ashamed. Though I did have a baby in that time so....life happens. This is the year though. We are going to get the pond working. We are going to swim. Wohooo! Pics to come.

From memory you need to mix the bentonite with the top layer.
Also, I think if its in a liquid form the leaks pull the bentonite into the leak.
From; Bentonite in dams
Bentonite blankets
Bentonite clay expands to several times its dry volume on wetting, and is therefore suitable to reduce the rate of water movement through porous soil.
The highest grade (with the greatest swelling characteristics) is sodium bentonite.
Calcium bentonite swells less than sodium, and is potentially less effective for dam sealing.
Impurities such as calcium and magnesium carbonates and quartz reduce effectiveness, and the fineness of grinding and screening
affects the ease of mixing with other materials.
Watheroo calcium bentonite is commercially available at several centres in the agricultural areas of Western Australia.
The product is sold unscreened in bulk, and screened in bags.
All sodium bentonite available commercially in WA is imported from the Eastern States or overseas.  
Laboratory comparison of a high grade sodium bentonite and the Watheroo calcium bentonite has shown that the sodium bentonite has significantly lower capacity to transmit water.

Bentonite can be applied either as a mixed blanket or a pure blanket.
A pure blanket is recommended if thorough mixing with the underlying soil cannot be achieved.
Less bentonite is required in a well-mixed blanket than in a pure blanket, to provide a sealing layer of a given thickness (e.g. 10cm).
Laboratory tests indicate that equal thicknesses of a 50:50 mix of bentonite and soil and pure bentonite have similar hydraulic conductivities or ability to stop seepage.
In a mixed blanket, bentonite is spread on the soil surface then mixed thoroughly into the top 10cm of soil using a rotary hoe, followed by compaction of the moist bentonite-soil mixture.
A protective layer of non-erodible soil should also be applied and compacted.

As a pure blanket, bentonite is spread uniformly over the soil surface to form a continuous sealing layer that is covered by a protective layer of non-erodible soil.
The protective layer should be compacted.
The required thickness of the sealing layer will depend largely on:
- type of bentonite;
- ratio of bentonite to soil; and
- uniformity of bentonite application.

Application rates vary considerably depending on the local conditions. As a guide, we suggest:
- high grade sodium bentonite – 15kgs per square metre;
- Watheroo calcium bentonite – 60kgs per square metre.
Based on these rates, the cost of installing a mixed blanket of calcium bentonite in an average-sized farm dam is approximately two to three times the cost of dam replacement.
The likelihood of reducing seepage to less than 2mm per day is estimated to be 50%.
Sodium bentonite is also available as a prefabricated liner consisting of high grade bentonite impregnated into a fibre mat.
Due to the need for specialised installation equipment and high cost of the mats, they are not generally suitable for farm dams.

John C Daley wrote:From memory you need to mix the bentonite with the top layer.

My biggest issue the first time around is that I could only put so much in the truck without ruining it. So I got as much as I could. It was around an hour drive to get it and when it leaked because I hadn't put enough on...well that was that. I tried calling the company to get some delivered but just had issues. Then I had issues getting bentonite in general until a rancher friend of ours gave me the name of the guy I am now getting some from.

Now that I have a local source I'm going to be putting way more bentonite on and *fingers crossed*

Good, I hope it goes well.

Progress pics. Got the bentonite. Husband decided he had to dig it larger immediately upon bringing bentonite home. So now reshaping pond and preparing for bentonite layer. Also working on the waterfall feature. I plan to have two barrels assist as bio filters and then the water go into a canoe we have that has a hole in it and waterfall down from there.

More pics

More pics

Canoe falls needs more thought. The water just kind of overflows and runs down the side of the canoe. Hardly a waterfall. Tried various angles. Same result.

The kind of bentonite I got is a top layer sealant. I was supposed to premix it and spray but it clogged my sprayer. So I spread it around and here we go.

Canoe falls needs more thought. The water just kind of overflows and runs down the side of the canoe. Hardly a waterfall.  

It's the shape of the canoe and its rolled rim - that round 'lip' encourages water to cling and flow inward toward the outer wall. It's very useful when canoeing, but not great for a waterfall feature.

Here's an idea:
Imgur link


If you drill a hole in the canoe, add a gasket and spout, you can have the water flow out of the canoe (maybe close to the upper lip) and over a rocky waterfall.
You could still have the pond pump move water into the canoe, and water come out of the canoe, and even plant a bunch of water-filtering plants up in the canoe to help with water cleaning.

But it'd remove the 'Canoe rolled lip pulling water toward it instead of spilling cleanly over'

I wanted to see what the canoe looked like in place. No wind at the time. Of course one huge gust came up and threw the canoe and top tire into the pond. /Sigh

Canoe has a hole in it though. I can do the falls out it maybe.

Fill the tyres with soil.
can you use a rotary tiller to mix the bentonite?