Yes, they do…I have a 100 gallon Horse trough under one downspout, and 2 55 gallon drums lying horizontally, in series under another…PLENTY of water for any gardening needs, and they fill up FAST!
There a re 3 “untapped” downspouts on the front of the house!
The roof contaminants, I mentioned, hence , pass on the “first flush” of your roof.
Me personally, I would forgo the water from an asphalt shingled roof, but a metal roof, no problem…Just forgo the “first flush”.
Throw a 5 gallon bucket under one of your downspouts next time it rains, and time it to full, then multiply by number of downspouts, and duration of the rain…You’ll be amazed.
And on your domestic water bill, is there a charge for “storm water abatement” or the like?
There is on mine, and they figure it by the sq. footage of your roof…I had the peoples from the “Water Authority” out to see MY attempt at “storm water abatement”, and got a 20% reduction on that particular bill addition, even though my catchments fill and overflow.
It’s makes one hell of a reservoir for pre-cooling water, prior to using some ice water and a CFC.
And think of all the peoples in the Caribbean,Central and South America, who use rainwater as their sole source for cooking and drinking…Your going to boil the piss out of it anyway…Think of it as " Fully Organic Beer"… :cheers:
Save it , “ITsPossible”…You won’t change my mind…