The sun wanes as I drive east towards the looming Rocky Mountains, leaving the vast expanse of the plains in my wake. I blast the air conditioning but the hope for comfort seems futile given the amount of time the car baked under the cloudless prairie sky. It’s a typical summer day on the eastern plains of Colorado, which early settlers called the great American desert. Yet fields of lush field crops and small towns punctuate the drive east on Highway 34. The heart of the transformation from desert to agricultural oasis lies in the discovery and exploitation of the Ogallala aquifer.
The Ogallala is the largest aquifer in North America. Developments in pumping technology in the 20th century facilitated the expansion of high capacity groundwater wells across the aquifer, turning the arid high plains into the grain basket of America. However, groundwater pumping rates that exceed natural aquifer replenishment threaten the future sustainability of the resource.
Aquifers around the globe provide vital water resources that allow agriculture to persist despite insufficient rainfall. Climate change compounds the implications of groundwater depletion on global food production by increasing the frequency and severity of drought. The future of the world’s aquifers and their ability to support agriculture depend on the development of management strategies that conserve groundwater for future generations.
The rate of groundwater depletion depends on the underlying characteristics of the aquifer, the density of groundwater wells and the rate of natural replenishment. Variation in depletion rates within an aquifer complicate resource management decisions and diminish the effectiveness of aquifer-scale conservation initiatives. In some areas of the southern Ogallala the water table, the vertical height of the aquifer, has fallen by more than 150 ft., roughly 70%. However, other regions in the northern Ogallala of the Nebraska have seen relatively small decreases in groundwater levels. To conserve groundwater resources, the aquifers of the world need management strategies that recognize this variation as well as the impact of groundwater extraction on the local economy when designing conservation initiatives.
The groundwater pumped from the Ogallala serves as the backbone of the rural economies built around irrigated agriculture. The economic impact of irrigated agriculture extends beyond the profit margins of farmers and ranchers. Irrigation creates jobs and supports local agricultural and consumer service industries. Aquifer conservation measures must account for the important role of irrigation in the local economy and aim to minimize the adverse economic impacts of groundwater management.
My research focuses on understanding how variation in aquifer characteristics influences the costs and benefits of differing management strategies. I integrate hydrologic, agronomic and economic models to investigate how groundwater users respond to conservation policies and changing aquifer conditions. Research results inform stakeholders of the tradeoffs inherent in alternative conservation strategies, allowing groundwater users to choose policies that best fit their community’s long-term objectives. I am currently working on an interdisciplinary research initiative funded by USDA-NIFA which partner economists, hydrologists and agronomists from research institutions across the Ogallala to create sustainable food production systems and rural economies across the region.
Conserving groundwater to meet future food demands and to sustain the agricultural communities built on irrigated agricultural requires management strategies that balance the costs of conservation today with benefits of a healthier aquifer tomorrow. Incorporating localized variation in aquifer characteristics and accounting for the economic impacts of groundwater pumping is paramount in designing policies that find this balance and effectively save groundwater for future generations.
To learn more about the Ogallala interdisciplinary research project visit OgallalaWater.org.