The yellow blinking light where Idaho state highways 20 and 75 intersect signals “almost there” to travelers bound for Sun Valley. It hangs in the southwest corner of a triangle-shaped swath of farmland that affords big-sky views of high-desert foothills that bleed into the Northern Rockies. A nearby mileage sign reads Bellevue 9, Hailey 12, Sun Valley 26. This August, I pulled off at a rest area next to the light. The air was still and warm. The sky was dulled by smoke from forest fires burning throughout the Pacific Northwest. I was road tripping to learn how the brewing industry sustains farmlands that surround our mountain playgrounds and wanted to soak in the view of them from here. My phone buzzed. Grumpy’s for a beer? Sure, I replied. I’m at the blinking light. Almost there.

At the northern tip of the triangle, near Bellevue, the Big Wood River courses over porous soils. Much of its water seeps underground and flows southeast until impermeable sediments and rock force it to emerge in a series of springs. Some of the springs refill the Big Wood; others feed Silver Creek, a world-renowned trout stream. Dayna Gross, the Idaho conservation manager for The Nature Conservancy, explains this hydrology while pointing out landmarks on a tattered GIS reference map on a wall in the cluttered office of the Silver Creek Preserve. The spring water is clean and nutrient-rich. Wetlands and wildlife abound. “That is why we have these epic hatches,” Gross says with a hint of in-the-know cool. “People come from all over the world to fish here.”Rough calculations by The Nature Conservancy suggest that visitors to the 851-acre preserve contribute more than $6 million to the local economy each summer and fall.

“Barley,” Bill Coors is famous for saying, “is to beer as grapes are to wine.”Barley supplied to brewers of beers such as Coors, Miller High Life, and Budweiser grows on farms that surround the Silver Creek Preserve and contribute around $20 million to the local economy. The relationship between the farmers and environmentalists is uneasy. Sediments wash and blow off the farms and cloud the creek’s waters. Wetlands are scarce. The valley’s aquifer is sinking from decades of over pumping and, as a result, the springs trickle with less vigor and creek waters are warming. MillerCoors contacted The Nature Conservancy in 2009 in search of ways to help growers of its barley be better neighbors. Gross suggested a fencing and wetland restoration project on a farm along Stalker Creek, one of the feeder springs. The brewer bit. “It was a real success,”John Stevenson, who has grown malting barley for 43 years at his Hillside Ranch, says while standing in a tractor shed to avoid the sun.