The Supreme Court's recent decision in Sporhase v. Nebraska,¹ although a narrow ruling as applied to Nebraska, could nonetheless significantly disrupt groundwater law in other states. In addition, while it reaffirms the leadership of states in water resources management, it makes clear that there are no constitutional obstacles to federal preemption of the increasingly vital and difficult job of groundwater management. Control over water, long a life-and-death issue in the semiarid states of the West,² is rapidly becoming a problem of pressing national concern.³ Groundwater supplies throughout the West are rapidly diminishing. For example, the Ogallala aquifer, which underlies the dispute giving rise to the Court's recent decision, is the nation's largest underground reservoir stretching from Texas to South Dakota. It has been depleting in many areas at the rate of three feet per year,⁴ and some predict that it will disappear within 40 years.⁵ The Ogallala and other groundwater supplies are increasingly under pressure from the needs of growing cities, from water-intensive energy development projects such as power plants and coal slurry pipelines, and from agriculture.⁶ Those seeking increased water supplies for such uses often must seek to import it from relatively distant areas of surplus. Many states, fearing that demands from outside their borders will prevent them from ensuring adequate supplies of water for their own citizens, have passed legislation to prohibit or limit interstate transfers of groundwater. At present, 14 states plus the District of Columbia have adopted such legislation.⁷ Not surprisingly, as the competition for limited supplies becomes more intense, some of these statutes have been attacked as unconstitutional burdens on interstate commerce.

In Sporhase, the first of these challenges to reach the Supreme Court, the Court rules, in a seven to two decision, that groundwater is an article of commerce and thus subject to both the restraints on state action and the potential for federal control created by the Commerce Clause. While it upheld Nebraska's conditions on interstate transfers, which parallel limits on intrastate use and are clearly designed to conserve diminishing groundwater supplies, the Court invalidated that part of the statute that prohibits transfers to states that do not allow their water to be transferred to Nebraska. Two dissenters, probably not coincidentally two westerners on the Court, disagreed not so much with the result, though they apparently would have approved the entire statute, but most strongly with the majority's reasoning and the limited weight it gave to the states' traditional control over their own water resources.