Next time you pour yourself a homebrew, consider what went into it. That glass of beer likely represents a little more than a quarter pound of malt plus a tenth of an ounce of hops. But it’s mind-blowing how much water was used along the way. It can easily take ten or more pints of water to yield that single pint of beer, even though most of the water never makes it into the brew pot or fermentor.
Where Does It All Go?
Some of the water gets tied up in the course of brewing and there’s not much you can do. The mash soaks up some. There’s dead space in your mash tun, in the area under a false bottom or below the level of the drain. Sparge water often remains in the transfer lines. A gallon or more is lost to evaporation. Then at the end, wort gets left behind in the dead space in your kettle, absorbed by the hops, and some might be left in your transfer lines or counterflow chiller. All of this together might add up to 5 or 6 gallons.
That’s a small part of the water bill, though. The lion’s share goes to chilling and cleaning. A wort chiller can use 15–30 gallons, depending on the temperature differential and use mode. Similarly, sanitizing your carboy and other gear and then cleaning up the brewery afterward can run through a tremendous amount of water. The good news is that you have a lot more control over these areas, so you can work to minimize what you need and reuse what you can.