Hart is one of nearly 150 growers in the valley that MillerCoors calls upon to supply it with malt-barley—a crop the company holds to an extremely high standard.
In fact, MillerCoors has nearly 850 barley growers in four states from which it sources roughly 70 percent of its barley. The company also operates its own farm in the San Luis Valley, and it recognizes the problem at hand, not just in Colorado, but in Wyoming, Montana and Idaho as well.
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That's why the company has made water conservation one of its key priorities from its breweries around the country to the farms that supply it.
"Bill Coors is famous for saying that barley is to beer as grapes is to wine," said Kim Marotta, who as director of sustainability for MillerCoors is tasked with reducing its water consumption.
The water worries in Colorado are not new. The area is a high mountain desert that receives on average just 7 inches of precipitation annually. The majority of its water comes from snowmelt off the surrounding Rockies.
"We depend entirely on snowmelt runoff and we live and die by that," Steve Vandiver, general manager of the Rio Grande Water Conservation District, told CNBC.
For the last six years, the region has had below average runoff because of below average snowfall in the mountains, which accounts for roughly 85 percent of the water that comes into the basin through the Rio Grande.
"It's getting worse as we go through time here, and we are hoping to see the weather change," Vandiver said.
MillerCoors has eight agronomists who work directly with the 850 farms to provide advice and support on the ground. As this growing season quickly approaches, the desire for support was evident at its winter growers meeting. Held in in a private room of a Mexican restaurant in Del Norte, Colo., the meeting was standing-room only, with roughly 100 farmers packed wall-to-wall to hear from MillerCoors and the water experts.
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"If we are not collaboratively working with our growers and others within our agricultural supply chain to become efficient, we are not going to create scale and we are not going to create impact," Marotta said.