Since the turn of the twenty first century, drought conditions have frequently stricken much of New Mexico. Such intervals of extreme dryness have been a permanent, recurring feature of the state’s climate for at least two thousand years, according to tree ring data and other scientific evidence. Some of these past droughts lasted for decades, exceeding in severity the Dust Bowl of the 1930sand the great New Mexico drought of the 1950s. Today, climate change models indicate that the Southwest will likely become even hotter, potentially making future droughts in New Mexico more extreme. Managing water shortages promises to become even more critical.
Across the west, water users and state officials have embraced a legal doctrine known as priority administration1as a tool for dealing with shortages. This process allows state officials to order a temporary reduction in water diversions for some uses so that other water uses can be supplied with the water that is available. However, state authorities seldom use this tool in view of the legal,economic, and political conflicts that would likely result. This article will describe how priority administration works, in theory and in practice. After describing priority administration as a general legal concept, the article then illustrates its practical role in four specific stream systems: the Cimarron River,the Mimbres River, the San Juan Chama Project, and the Pecos River