Slip formed cistern

[humbug]

I have read a couple of articles that mention people building slip formed cisterns or water tanks. I have not been able to find any plans for these or even pictures. Anyone have any info on these?

[bee_pipes]

In BHM #101 is an article by Dorothy Ainsworth titled "Build a 6500-gallon concrete water tank for $1500". The project is pretty ambitious and I don't know how big you want it, but you can view it on-line at http://www.backwoodshome.com/articles2/ainsworth101.html

Hope that helps. When you start building, be sure to post info on lessons learned and pictures of progress.

Regards,
Pat

[chrisser]

I saw the article Pat posted. It is very interesting and informative.

If you intend to build the structure to be free-standing (as opposed to being sunk in the ground and backfilled), it might be constructive to get the advice of an engineer.

A vessel of a large size filled with water needs to be very structurally sound - if all that water were to be released suddenly, it could make a real mess of anything nearby or downstream. A sudden, catastrophic failure could easily damage a nearby buildinng (or person, or vehicle). Even a moderate leak could cause many problems as stopping it could be difficult at best.

And, I hate to mention this, but if you have homeowner's insurance, I doubt damage to your home caused by your homebuilt water tank suddenly breaching would be covered. If you have a helpful insurance agent, you might want to involve him in your plans too.

Not to deter you - just do your homework before you spend the time and money.

[Gibbonboy]

I've built two cisterns in my life- one roofed-over like in the article, and one out in the woods to collect water from a spring and funnel it into a pipe that carried it to a prefab tank. The roofed-over one was 14 feet wide, 24 feet long, and held a maximum of 4 feet of water. It was constructed of poured reinforced concrete, and we put tile over the Thoroseal. I've also worked forming concrete on two "full-size" dams, and the pressures there are incredible. We had to put a PVC piece in between sections of concrete, to keep the water from forcing its way between. You could probably do that with a piece of EPDM liner, put the strip halfway into one pour, then when you pour the adjoining lift, the other half will be in there. I mean this for cases like the wall/floor joint shown in the article. Also remember to carefully varmint-proof the structure, never a good feeling to find a dead possum in the cistern. We used to have salamanders in ours, they're almost impossible to get rid of. Shows that the water quality is high, though. Best of luck.