One example comes to mind. Flow restrictors on faucets.
Supposing I'm washing the car. I need five gallon bucket,
half full of hot water and soap. If I half-fill the bucket
off unrestricted faucet, it half-fills in about a minute.
And suppose I half-fill the bucket on a sink that's got a
1.5 gallon per minute aerator, on it. It takes much longer
to half-fill the bucket. Now, for 10 bonus points, and one
letter grade increase. How much water was saved by using the
flow restricted faucet, and waiting several minutes to
half-fill the bucket?

And how much extra did that flow restricted faucet cost me,
to install?

--
Christopher A. Young
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