And how does the water get into the cistern, may I ask? Are you pumping it?
If so, the net expenditure of power is exactly the same, except for some
small losses. It's called conservation of energy.

Apart from that, balancing a ton 9 feet in the air is tricky business, as
others have pointed out, and it isn't going to look very nice either. Of
course they do this sort of thing all the time in Mexico. But four 4x4
posts set 2.5 feet deep on some nice flat rocks and then concrete around
them with some good X bracing will certainly carry the load, barring an
earthquake. You should brace zigzag fashion, i.e., two X's on each of the
four sides. And even so, if someone drives into this monument with a
pickup, he or she could be killed.


"Cristian" wrote in message
...
On Wed, 16 Jul 2003 13:07:01 GMT, "Gary Slusser"
wrote:


"Cristian" wrote
Hi,

I have a plastic water cistern/reservoir (cubic shape, 1000 liters or
250 gallons) and I would like to install it on 4 vertical wood
pillars, 4x4 size, at 7-9 ft height.
I need some suggestion about the structure in wood to construct in
order to be secure. Is this size (4x4) able to sustain the full
reservoir? What kind of simple wood structure should I build in order
to be secure. How many pillars, how to fix the pillars one to the
other, supplementary reinforce, etc.
The cistern is not very heavy when is empty (less 50 kilos).

Thank you,
Cristian

Well it will be heavy when filled. Water weighs roughly 8.5# per gallon.
Cross bracing in is order and it should reinforce the 4x4s to keep them
straight. That's a small foot print for the height. Why not on the
ground and a small pump?

I would like to use the fall of the water (no cost) instead of using a
pump with extra cost (each time I need water the pump should start,
etc).
The water is usually used for water the garden.

Cristian