When Freddie Botur, 45, whose ranch spans 72,000 acres outside of Pinedale, Wyoming, first heard about a program that was paying ranchers to let water run down the river instead of irrigating with it, he was skeptical. But Nick Walrath, a project coordinator for Trout Unlimited, told him he’d receive about $200 for every acre-foot of water saved by not watering hay on his Cottonwood Ranch. For Botur, it would mean over $240,00 for fallowing just over 1,700 acres of hay fields for the latter half of the summer of 2015, letting 1,202 acre-feet of water run past his headgate on Cottonwood and Muddy Creeks, tributaries of the Green River, instead of to his fields. “Oh my god,” he thought, “this is insane.” Botour, talkative and athletic, was wearing mirrored sunglasses and a cowboy hat when we met in June outside a cluster of old homestead buildings on the family ranch that he operates at the foot of the lofty peaks of the Wyoming Range. For Wyoming ranchers, he explained, the kind of money he received for not growing hay represented as much as a third of their annual revenue. The money-for-water program that Botur signed up for was a pilot program, launched in 2014 by the four largest municipal water providers in the Colorado River basin along with the Bureau of Reclamation. The goal: see how complicated it would be to pay ranchers to use less water on their fields and instead let the water flow down the Green, Colorado and San Juan rivers to Lake Powell and Lake Mead, the two biggest water storage buckets in the Colorado River system. The result: After three years, the initiative, known as the “System Conservation Pilot Program,” proved popular with skeptical ranchers like Botur, but water officials called a halt to the program after this year until they work out some big challenges. Their task will not be easy. But as climate change alters the hydrology of the Colorado River basin, water planners are searching for ways to adapt a system of century-old water laws to a new reality. If they’re successful, a revamped “system conservation program” could be one way to reshape water management for a hotter drier West.