Living in rural Australia means collecting water for household use from the roof when it rains. The water is stored, in our case, in two 5000 gallon (6000 US gallon / 22,000 litre) tanks. I checked the water level (it’s pretty high) then reflected on the matter. (I cleared the leaves out before putting the filter back over the inspection hole).
[An entry to the December 4, 2004 “Photo Friday” challenge].