All four regions tell of the essential role water has played in western agriculture and the importance of this agriculture for settlement of much of the West. They also exemplify the many difficulties of turning prairie and desert into productive croplands, and MacDonnell describes the sometimes extraordinary human committment and effort that made this possible.
Now, however, western water resources have been developed beyond their sustainable capacity in an attempt to irrigate as much land as possible, and MacDonnell illustrates the consequences of this overdevelopment, including declining rural communities, dewatered streams incapable of supporting native species, and degraded water quality. He also provides examples of efforts to repair some of the damages and of the challenges involved in such restoration.
MacDonnell argues that sustainable use of the West's water resources depends on reducing the gap between diverted water and used water, restoring the functional ecological integrity of water sources, allowing uses of developed water to change, and effective collaborative public/private processes that help reconcile competing interests in water. He concludes that the manner in which the West moves toward sustainable use of its limited water resources--particularly as it affects irrigated agriculture--matters at least as much as achieving sustainable use. It matters because the choices we make will have important consequences for the future West.
