Pretty much everything that’s in wine comes in the amazing grape, remember? And yet it takes a lot of water to make wine.
Not as much as coffee, mind you, but a lot. Here’s one water-use estimate for wine and some other products that’s been widely circulated since it appeared in The Economist several years ago:
So that raises some questions. Like: How come it takes so much water to make wine? And with water scarcity an increasing concern – in drought-stricken California, for sure, but other winemaking regions as well – should you feel guilty when you have a glass of wine? And what if anything are wineries doing to reduce their water footprint?
How Wineries Use Water
First, we should say that not everyone buys that chart above, which, when you do the conversion from metric, gives a water toll of 29 freaking gallons of H20 for a 4.2-ounce glass of wine (a light pour, by the way).
That includes the water used on the vines, the water used in the winery – and rainwater. Rainwater? The idea is that the crops are consuming the rainwater, instead of allowing it to replenish the groundwater supply. Hmm.
The wine writer Mike Dunne wondered about this calculation, too, so he drilled deep into the question of how much water wineries use, focusing on his home turf of California. He came up with a range of figures, depending on location and practices, from 2 to 3 gallons per glass at the low end up to 15 gallons at the high end. If you click around the Web, you’ll find many different figures, but none of them seem to be as rigorously developed as this range.
A good portion of that water use can occur in the vineyard, even if you don’t count rainwater. Crops in many if not most areas of the world are irrigated. Even the French wine authorities, who used to treat irrigation as though it were a mortal sin, now allow it, although with some restrictions.
Compared to other crops, though, grapes don’t have a huge water appetite. Again looking at California, where the issue has been studied most intensively, wine grapes require about one-third the amount of water used to grow those notorious water-hogging almonds we’ve all heard about.
Then again, water is also used in the vineyard for frost protection in the early spring. This is done by spraying water on the vines when the temperature is around freezing and down to as low as 28 degrees. As the water freezes, it releases latent heat, keeping the tender vine shoots from succumbing to the cold.
In the winery, the water use is all about sanitation. You’ve probably heard the saying, “Great wine is made in the vineyard,” but if you watch a winemaker in action, you might think that cleanliness is what really matters. Barrels, tanks, presses and crushers are meticulously cleaned after every use. Not just “looks pretty clean” clean, but free-of-possible-contaminants clean.
No Need to Feel Guilty, Though
While it’s true that wine has a pretty big water footprint, let’s put things in perspective. A quarter-pound of beef, enough to make a modest burger – and we’re just talking about the beef here, not the lettuce, tomato, pickles, ketchup, etc. – requires 450 gallons of water to produce. And the same group that pegs wine’s water use at 29 gallons per glass says a 1-ounce piece of chocolate takes 127 gallons of water.
So a glass of wine with dinner that requires 5 or 10 or maybe 15 gallons of water to make? Don’t sweat it.
Meanwhile, Wineries Are Working to Use Less Water
Wineries are trimming their water use in the vineyard and in the winery. Rare is the vineyard these days that doesn’t have drip irrigation. Plus, that drip irrigation is often control by very sophisticated sensors in the ground and air that ensure not a drop more water is used than necessary.
Many wineries have also found that giving the vines less water than they traditionally had can lead to better grape quality. This is a practice called deficit irrigation. Seems a vine that has to struggle a bit will produce a tastier grape.
Some wineries are installing onsite water treatment systems that capture and treat water used to clean equipment, allowing it to be used again.
Other wineries pump that water out to the vineyard, using it for irrigation.
High-pressure, low-flow devices – the same kind of thing you might have put in to reduce water usage in your shower – are helping trim water use, too.
Finally, some of the water-saving “innovations” aren’t very high-tech at all – they’re things like sweeping the floor before hosing it down; waiting until all the grapes have been unloaded out of a bin or a tank before hosing down the floor; and just being hyper-aware of how water is being used. (Unlike that guy in the picture, right?)
We ask – and answer! – more winemaking questions at these links: