We have several of the billboard tarps. Very heavy. I think it could work well, as long as there is a thick layer of sand over it and no animal traffic or other pokies. However, a real pond liner is much thicker and will self-heal to a degree. Best of all, clay in the soil.
My five acres percs like a sieve, and by and large water soaks right into the ground and rarely puddles, except during periods of heavy rain -- which we get plenty of in the NW -- but even then not for long. Therefore I never thought of having a pond, or even a mini-pond, because of the hassle of installing and maintaining a liner.
But because I raised my most recent batch of hogs through the winter, I got to test first-hand Sepp Holzer's assertion that wherever hogs wallow, they will seal the low spots. My small sample of observation confirms Sepp's hypothesis. Water now puddles and remains in every shallow depression, in areas that I had observed to be quick drainers, because the hogs were there.
Once the hogs were butchered, I reseeded that field to pasture. I'll be interested to see what grows in those depressions, and how it grows. It should be an interesting exercise in micro-environment.
But now I have a much stronger suspicion that if I was to plan a pond, I might want to dig it, but not fill it, till I let the hogs have their way with it. As with clearing blackberries, I have no desire to "do the pigs' work." Walter, have you experienced this?
If you are using tarps (or other thin materials) to line a pond, punctures are a serious consideration. A good (and usually free) way to mitigate the problem is to first lay in a section of used carpeting, fluffy side up. Craig's List, or carpet companies are good sources of finding free, used carpeting. Indoor/outdoor carpeting would probably be even better.
If you lay the carpeting in the hole with the nap facing up, you have created a surface that will cushion the tarp, and isolate it from any sharp pebbles in the underlying soil. If you place a second carpet on top of the liner (this time nap facing down) you have also helped to isolate your liner from animal hooves (or drunks with high heels). You just have to anchor the edges well with soil or rocks.
Sometimes you feel like a nut. Sometimes you feel like a tiny ad.
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