the.com/rainwater

Tap water that fell for free and still thinks it's pure.

means Water collected from rain, before or instead of running through a municipal pipe system.

from A straightforward compound of 'rain' and 'water,' both ancient Germanic words — 'rain' traces back to Old English 'regn,' 'water' to Old English 'wæter.' No hidden story here: English speakers have been pairing the two plainly, as 'rainwater,' for centuries, to mark it off from well water, river water, or anything that came through human plumbing.

actually
picks up pollutants, pollen, and roof grime on descent
historically
flavored soap and shampoo before plumbing existed
ph level
naturally acidic, around 5.6, even without pollution
harvesting
one inch of rain on 1000 sq ft yields 600 gallons
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