Cheap and Fast Rainwater Tank - 7,000 gallons

Here's a cheap and easy way to make a huge rain water tank. This tank cost less than $1,000, and it holds over 7,000 gallons of water:

http://www.velacreations.com/blog/item/280-barn-tank.html

Very cool idea, and since we're using a ton of cattle panels for fencing, we might actually have some of the materials on hand already. Are you at all concerned about UV degradation of the exposed pond liner?

Thanks,
Doug

well, I'm planning to put a roof on it, but these pond liners are designed to be exposed to UV for some time. They come with a 25 year warranty.

So, I wouldn't worry about it too much.

If you have cattle panels, just make it round, as it is easier to put together (no posts or ropes).

Yup, cattle panels do bend nicely into (big) circles. I was thinking, vis-a-vis the pond liner, that in a typical pond situation the liner is either under water or (at the edges) covered with stone or other landscaping. The roof should eliminate any concern, though.

Doug

Doug Gillespie wrote:Yup, cattle panels do bend nicely into (big) circles. I was thinking, vis-a-vis the pond liner, that in a typical pond situation the liner is either under water or (at the edges) covered with stone or other landscaping. The roof should eliminate any concern, though.

Doug

the water won't protect it from UV, unless it is really deep. A simple dome roof like from a grain silo or maybe an old satellite dish would work.

If you do cattle panels, make sure you tie the joints together REALLY well. I learned this the hard way...

tie them together really well, and also use a retaining ring at the top and bottom. This can be rebar or tubing, but it will help hold things together.

Abe,

I remember reading someone asking, either here at permies or at your site, if you could do this as a round tank. I was researching gabions and found this site: http://www.ceshepherd.com/quick_water_tank.html. I thought you and the other readers might be interested in the design. I am looking for pricing on the spiral binders that appear to be required to connect the welded wire panels or rolls together securely. Hog rings won't do.

yeah, I have seen those tanks before. Yes, you can make this round. The spiral binders are not required. Just overlap the mesh a foot or so, and tie with tie wire at every intersection.

Then, make a retaining ring at the top, bottom, and 1/3 the height. The retaining ring could be as simple are steel strapping or rebar. It should go on the outside of the mesh.

Hey Abe, how is the tank holding up? I cant see myself making one that big, but a smaller, round tank would be great.

I made several cisterns of related design for free and cheap on our old place in GA. The principle was taken from the "carpet sandwich" pond liner idea. Think of the carpet sandwich in a basket. The first one I made was actually in a wooden basket, with vertical poles and saplings woven between them. A stout cable held the poles together at the top (and the ground did so at the bottom). In goes first a layer of overlapping carpet scraps, tied to the basket however, then a pristine piece or two of new, heavy duty builder's plastic, and then another layer of carpet scraps....this last mostly to keep the sun off the plastic. Then I did several more much quicker and easier.....first measure the width of the plastic available (commonly you can get a roll 20 feet wide, wider at a greenhouse supply place). Then drive a circle of metal stakes or pipes into the ground so that the height of each side plus the diameter across is slightly less than the width of your plastic. Next, back fencing against the stakes on the inside. It can be any kind of fencing without barbs...I've used chain link and common woven wire with good results. Wire or tie it to the poles in a few places so it stays put. Add a cable or a stout rope around the circumference of the poles at the top. Then line the basket. Not only carpet scraps but I've used silt fence and fiberglass shade-cloth, two layers thick on the outside, to good result. Against the ground, anything can work...old plastic, old tarps, etc. It just has to not rot and to cushion the new plastic from punctures. Then, follow on with the plastic. It helps to get some water in it at this stage to help the plastic unfurl and fill into the corners. Tie it off over the top edge by wrapping baler twine tucked around rocks at the perimeter. Last, add an inner liner, in large overlapping pieces. Silt fence may try to float...weight it down with rocks if need be. Set up a siphon to get the water out....much safer than trying to puncture through the liner. Don't try to use more plastic by making the cistern oval...the pressure of the water will always try to pull the top of the thing back to round.... I impounded thousands of gallons of water this way and those cisterns lasted at least five years....

William Bronson wrote: Hey Abe, how is the tank holding up? I cant see myself making one that big, but a smaller, round tank would be great.

The tank is holding up great and is full of water. We put a greenhouse plastic roof on it, but I'm looking for a better solution, maybe a floating green roof.

We have made both potable and nonpotable round tanks that work really well: http://velacreations.com/water/water-storage/313-cistern-howto.html

The round tanks are easier to construct, so that's what we do, now. If you can buy a replacement pool liner or get a cheap above ground pool on Craigslist, then you can make a nonpotable tank very cheap and easy.

I have been gorging myself on the content from your site!
You seem to innovate in everything you do, what fun!
We as a family just bought an urban lot to shape to our own liking and I have found your examples to be inspiring.
I think we will stick with 250 gallon totes for now, as they are cheap, and intend to in incorporate them into the structure of a shed.

Btw, I happen to have a large collection of new and used blue tarps. I know they will die pretty quickly when exposed, do you have any idea how they weather when submerged and of underground?

I've had a blue tarp last a few years underground, but I have no idea about under water.

Thanks for the kind comments about the site and information. I appreciate your feedback.