The entire West is headed for a much drier future. Ogallala Blue provides a good sense of the bleak realities of a life of scarcity.

Author William Ashworth focuses on the Great Plains states, which have for decades thwarted a notorious lack of rain by reaching into the massive Ogallala Aquifer. Today, those states grow more than a fifth of the nation’s crops. But Ashworth deftly shows that, as successful as High Plains farmers have been at transcending the limits of aridity, they have done so only by plundering the aquifer.

Some of the effects of groundwater dependency make intuitive sense. As farmers have to spend more and more money to reach the falling water table, they have three options: Grow better-paying crops, "consolidate farms in order to make an adequate income," or — in what’s becoming a tedious refrain in the West — turn the farm into a housing development.

Some of the effects of groundwater dependency make no sense at all. A farmer spends $40,000 on a center-pivot sprinkler, to keep his crops watered even when it doesn’t rain. Having replaced meteorologic uncertainty with an irrigation schedule tightly tailored to the needs of his crops, his biggest fear becomes … rain.

Ashworth covers much of the same ground John Opie traveled in his book, Ogallala: Water for a Dry Land. But Ashworth has startling insights of his own, including this one: Conventional wisdom, which encourages farmers to make the investments necessary to improve their irrigation efficiency — thereby stretching the remaining water in the aquifer further — may not, in fact, be wisdom at all. To recoup their investment, farmers end up growing even more crops, using more water to do so. Ultimately, their efforts hasten, rather than delay, the end of the aquifer.