"Once, during Prohibition, I was forced to live for days on nothing but food and water." W. C. Fields

The concrete water tank started to leak so I decided to invest in a new 3000 litre plastic one. Shuggy excavated the site

et voila. 

The supply is from a small spring - just a trickle - but enough to keep the tank filled. The water is crystal clear but I'll probably get a UV filter