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What are interstate water compacts?
An Interstate Water Compact allocates water rights to particular bodies of water to the party states. "An interstate compact is an agreement between two or more states of the United States that is approved by those states’ respective legislatures, and, if required based on the subject matter of compact, consented to by the US Congress." Library of Congress June 2018 Interstate Compacts in the United States at 1.
Interstate compacts are negotiated contracts between two or more states. After the compact is negotiated, it must be approved by the legislatures of the states who are a party to the compact. Once approved by the state legislature it becomes a state statute. The US Constitution Article 1 Section 10 requires congressional approval of compacts between states. However, the US Supreme Court in 1893 held in Virginia v. Tennessee, 148 U.S. 503, consent is required only if it is “directed to the formation of any combination tending to increase of political power in the States, which may encroach upon or interfere with the just supremacy of the United States”. Interstate Compacts in the United States, Library of Congress June 2018 Id.at 2
Interstate Water Compacts
This research guide looks at interstate water compacts within the United States, specifically Arizona, California, Colorado which fall within the western states of the United States where water is scarce.
History of Interstate Water Compacts in the Western States
The Colorado River Compact
1922 was an agreement among several western states including Arizona, Nevada, Colorado, California, New Mexico, Utah, and Wyoming. This was the first major interstate water compact for the western states. The purpose of the compact was to provide equitable division and apportionment of the use of the water of the Colorado River System; to establish the relative importance of the different beneficial uses of water; to promote interstate comity; to remove causes of present and future controversies; to source the expeditious agriculture and industrial development of Colorado River Basin, the storage of its waters, and the protection of life and property from floods.
Arizona v. California, 373 U.S. 546 (1963)
involved the apportionment for the Lower Division states for the mainstream water of the Colorado River. The Supreme Court largely affirmed the decision of the specially-appointed Magistrate, and noted that the Colorado Compact and the state's apportionment law statutes did not supersede the Boulder Canyon Act; the Colorado compact did not precisely address how the Lower Division states were to apportion the water among themselves.
Interstate Water Compacts Cases
S.J.D Candidate, Elisabeth Haub School of Law at Pace University
Impact of Climate on Interstate Water Compacts