In article 25Swc.16245$Sw.12946@attbi_s51,
(Chuck Yerkes) says...

What does a 2500 gallon tank cost? Is it buried? It's plastic of
some kind I assume.

It cost me about $700, on sale at the farmer's co-op. It is an above
ground tank, and yes, it is a black plastic, which minimizes algae
growth. I have it set above the level of the house, so when the power
goes out we have gravity feed water from the cistern, with enough
pressure to flush the toilets.

2500 gallons lasts us about 10 days in the summer, with no irrigation.
The well did go dry a couple years ago during a "drought of the
century" scenario. I had water hauled in by truck. The most a dual
axle tanker can haul is about 1800 gallons, so I could take a full load.

During normal drought years, the well just goes low flow in the summer.
I keep it regulated to 1 gpm, which is plenty to keep the cistern full.

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