The amount of water in a standard can of beer is about 92 percent and for the brewing business, it’s not just the water going into the cans, it’s the water used to clean tanks. Charlie Bamforth, a distinguished professor of Malting and Brewing Sciences at the University of California, Davis says even before the drought in California, beer brewers were very conscience of how much water they used.

"You need a lot more water than ends up in the beer. Because you use water for cleaning, and you use water to make steam, which is used to heat the vessels. And you need water for cooling and so on. So the best run breweries are somewhere around three to one. Three barrels of water for every barrel of beer."

Bamforth says the more beer you make, the more efficient the water use.

"If you’re brewing beer, and you’re filling a tank, and that tank has a pipe attached to it and you’re serving it upstairs in a pub, that’s very different than putting beer into bottles. You use a lot of water when you’re bottling beer in terms of cleaning, if you’re pasteurizing to operate the pasteurizer and so on."