I never said it was pure and I never said I'd drink it "pure" and even gave a specifically bad example (the asphalt shingle roof runoff) and mentioned proper tr

I never said it was pure and I never said I'd drink it "pure" and even gave a specifically bad example (the asphalt shingle roof runoff) and mentioned proper treatment and catchment. This is not the kind of system you'd probably find doable on a small city lot and yes I guess people would be tempted to just drink their asphalt shingle roof runoff - until they see the water. But the context presumably is acreage type off-grid living. The landscape can also help. Dunno if you saw a recent-ish article here on HN on some South American farmers directing rain water such that it flows slowly through various layers on slopes until it reaches the bottom even having it re-emerge as natural springs in some places. Won't work if you live on the prairies, sure. Could work in other locations.