After years of drought and overuse, the San Luis Valley aquifer refills
How an over-taxed basin is getting its water use under control.
High Country News
The San Luis Valley in southern Colorado is an 8,000-square-mile expanse of farmland speckled with potato, alfalfa, barley and quinoa fields between the San Juan and Sangre de Cristo mountain ranges. Only about 7 inches of rain fall each year in the San Luis Valley. But while farmers and ranchers can’t depend on moisture above ground, they make up the difference beneath it. The valley is underlain by a vast aquifer, which is punctured by more than 6,000 wells that pump water onto the valley’s crops and supports the livelihoods of 46,000 residents.
For generations, the aquifer provided enough water to sustain the arid farming community. But beginning in 2002, a multi-year drought shrunk the nearby streams and water table. Farmers and ranchers began to notice the falling levels of the Rio Grande River and the rapidly draining aquifer. Some wells throughout the valley abruptly stopped working.
The aquifer dwindled so much that the Closed Basin Project, a Bureau of Reclamation pumping effort that had long met downstream water diversions and delivered flows to the Rio Grande River to maintain the Alamosa National Wildlife Refuge, failed to convey enough water to the valley’s farms and ranches. “We operate in a highly over-appropriated system,” says Cleave Simpson, manager of the Rio Grande Water Conservation District, the main water management entity in the San Luis Valley. “Agriculture had overgrown and far outstretched water supply.”
Without change, state water regulators could shut off thousands of wells. So the valley’s farmers and ranchers, unlike other agriculture communities in the West, did something nearly unprecedented: They decided not to ignore the problem.
In 2006, the Rio Grande Water Conservation District and San Luis Valley water users created the sub-district project, an innovative solution for solving water problems. The plan would charge farmers and ranchers $75 per acre-foot for the groundwater they pumped, and in turn use the funds to pay farmers to fallow portions of their fields, limiting demand on the water supply, as High County News reported in 2013. The experiment began at sub-district 1, the valley’s largest of six sub-districts, which sits at the heart of the San Luis Valley in aptly named Centre, just west of the Great Sand Dunes National Park.
Today, four years into the operation of the project after it launched in 2012, the aquifer is rebounding. Water users in sub-district 1 have pumped one-third less water, down to about 200,000 acre feet last year compared to more than 320,000 before the project. Area farmers have fallowed 10,000 acres that once hosted thirsty alfalfa or potato crops. Since a low point in 2013, the aquifer has recovered nearly 250,000 acre-feet of water. By 2021, the sub-district project plans to fallow a total of 40,000 acres, unless the ultimate goal of rebounding the aquifer can be reached through other conservation efforts, like improving soil quality and rotating to more efficient crops.
The plan’s proponents say it provides a template for groundwater management in other arid communities whose agricultural economies are imperiled by drought. “The residents of the valley know that they are in this together, and that the valley has overgrown the water available to us,” says Craig Cotten, Almosa-based division engineer for the Colorado Division of Water Resources. “This is a water user-led solution, which makes it unique. I really think this can be a model.”
Crucially, the plan is state-mandated, which requires everyone to either participate in a district, fallow their fields or work with water engineers to develop their own augmentation plans, which in turn need to be approved by state water courts. Those choices — paying premiums for groundwater or scaling down operations significantly — have been tough for farmers. Nevertheless, Simpson says the valley’s water users have gotten on board. “It’s not comfortable but most everyone has really come forward,” Simpson says. “It’s a bit of a paradigm shift for farmers who are individualistic and don’t typically work together — but by necessity they realize that we will bankrupt ourselves if we continue to stretch our water resource.”
But water users in the San Luis Valley have also gone beyond the call of duty, says Heather Dutton, manager of the San Luis Valley Water Conservancy District. While the SLVWCD helps include users in its augmentation plan as an alternative to joining the sub-district project, Dutton says that few water users have gone that route. That’s partly because farmers and ranchers themselves have helped create the sub-district rules, through participating in public meetings and getting involved with the board of managers. “This has been a good exercise in self-governance,” Dutton says. “It’s been a success story in people coming together and trying things that my grandpa’s era would have thought were crazy.”
Although sub-district 1 has proved a success, the broader sub-district project remains in its fledging stages. In March, Colorado District Court in Rio Grande County mandated that sub-district 2, a cluster of a hundred or so wells between Monte Vista and Del Norte, unroll as phase two of the program. The second district is currently forming a board of managers to develop official rules for farmers and ranchers within the territory. The Rio Grande Water Conservation District is still working with valley residents to implement the remaining four sub-districts.
Still, the project’s first phase has been encouraging for residents. Patrick O’Neill grew up in Central California’s San Joaquin Valley and first came to the San Luis Valley in 1998 to work as an intern at Agro Engineering, a consulting company. Though he later returned to his family farm in California, he came to feel that the Central Valley, built on its own wasteful groundwater use, was not sustainable. He returned to the San Luis Valley in 2005, where he now owns Soil Health Services in Alamosa and works with area farmers and ranchers to improve soil health. “I chose this place in a very deliberate way for my home because there’s potential for putting our water system back into balance,” O’Neill says. “People here are much more conscious of how much water they are using.”
George Whitten, a long-time farmer, says the drought has provided a tough but valuable lesson for the San Luis Valley. “It’s a beautiful segue,” he says. “The drought has caused people here to think about the future. Soil is no longer just a medium to put seeds in and water isn’t endless. It may take awhile, but I think we will wind up as a healthier community because we had to come together to restore the aquifer.”