The Texas High Plains: a story of two parts

CASE STUDY: PERMANENT WATER

The Texas High Plains: a story of two parts

Fertile soils, favourable growing conditions and irrigation from the Ogallala aquifer have made the Texas High Plains one of the most productive agricultural regions in the world (Weinheimer and others, 2014). Although groundwater is the main source of irrigation, the plains’ playa lakes are its most important hydrological feature. Playas are shallow, circular-shaped, rainwaterfilled wetlands, though in cropland settings some receive water from irrigation run-off (Texas Parks & Wildlife, n.d.).

La Niña has long been associated with drought in the plains, as the phenomenon intensifies precipitation and temperature extremes. Climate change is adding to these extremes by raising average temperatures and increasing evaporation and surface drying which, in turn, drive demand for more irrigation.

Water changes in the Texas High Plains are therefore a story of two parts: first, the area’s capacity for irrigation despite its warm, dry climate, thanks to the Ogallala aquifer, which has also led to increases in surface water from irrigation-related spill-overs; and second, the recent focus on water conservation efforts to reduce groundwater dependence and to help preserve the rapidly depleting Ogallala aquifer.

Joel Dunn on Unsplash

Figure 10. Intensity map of water changes in playa lakes near Floydada on the Texas High Plains (left) and changes in terrestrial water storage (right)

Sources: European Commission (n.d.); Strassberg, Scanlon and Chambers (2009); Gravity Recovery and Climate Experiment (GRACE) (n.d.).

Note: While terrestrial water storage (TWS) represents both the water stored on and below the land surface, studies have documented the close correlation with TWS and groundwater storage changes on the High Plains’ aquifer.