Back in 2007, Levi’s did a cradle-to-grave assessment of the resources required for its famous 501 denim and found out something surprising: its jeans were practically made of water. The San Francisco-based company discovered that over the lifetime of its jeans, from the cotton fields needed to make the fabric to consumers’ tossing their dirty dungarees in the washing machine, each pair used up 3,480 L of water, which is the equivalent of running a garden hose for 106 minutes.

There wasn’t much Levi’s could change about cotton farming or consumer hygiene, but company executives realized they could use ozone processing to reduce the amount of washing needed to soften jeans before they’re sold – i.e., the wash in stonewashed. The result is Levi’s Water-Less jeans, a new line that hits stores in January. On average, the jeans, which will cost the same as conventional ones, use 28% less water in the finishing process. Multiply that by the more than 1.5 million pairs of Water-Less jeans Levi’s expects to sell this spring and the savings add up to approximately 16 million L of water. “It took a different way of thinking, but the results are kind of amazing,” says Carl Chiara, director of special projects at Levi’s.

Fashion may seem low impact – after all, consumers don’t use electricity or burn gasoline when they put on their khakis – but growing cotton and other fibers involves a lot of water and fertilizer, and a great deal of energy is needed to manufacture, ship and, eventually, wash and maintain the clothes that wind up in your hamper. Some 25% of the world’s pesticides, for example, is used to grow cotton, and on average, 15% to 20% of the fabric that goes into producing clothing ends up as scraps.