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Interstate Compacts


INTERSTATE COMPACTS. Article I, Section 10, of the U.S. Constitution authorizes the states, with the consent of Congress, to make compacts among themselves. The Compact Clause says, "No state shall, without the Consent of Congress, … enter into any Agreement or Compact with another State, or with a foreign Power. …" The U.S. Supreme Court has interpreted this provision to mean that Congress must approve only those interstate agreements that affect the balance of power within the federal system. Furthermore, such approval can be implicit, found in subsequent Congressional acts recognizing the results of the interstate compact (Virginia v. Tennessee, 1893). Administrative agreements or administrative amendments to other agreements do not require congressional approval.

States began making agreements among themselves early in the nation's history. In the colonial period, nine agreements on boundaries existed, and four more were made under the Articles of Confederation. In the first century of the Republic, interstate compacts were limited chiefly to a few boundary agreements; only twenty-four were ratified from 1783 to 1900. A large increase in compacts began in the 1930s, when the Council of State Governments and other organizations began wholehearted encouragement of interstate cooperation as an alternative to federal administration of all interstate issues. By the mid-1970s, the number of compacts approved was over 200, and they affected important governmental responsibilities.

Perhaps the most significant agreements are the river development compacts, which deal with irrigation, pollution control, fishing, and navigation. Federal sponsor-ship of the Colorado River Compact (1928) did not succeed in precluding a long litigation between two of the six states involved, Arizona and California, but the Upper Basin agreement seems to have worked well. The Delaware River Basin Compact (1936) was novel in that it included the federal government as a participating member, as well as the four states directly affected—New York, New Jersey, Pennsylvania, and Delaware. The New England Interstate Water Pollution Control Commission, which was formed in 1947, expanded its powers to include regulatory activities in the early 1970s. The Susquehanna River Basin Compact of 1969 (which deals with planning land use), like the Delaware compact, also includes federal participation.

States have made agreements among themselves covering a wide range of other issues and activities, including child custody and placement, educational policy, administration of criminal law, use of natural resources, protection of the environment, transportation, and utility regulation. There are a number of regional development and planning compacts. And one important compact, the Port Authority of New York (1921)—also the first joint administrative agency of a continuing nature—does a multibillion dollar business involving airports, bridges, and tunnels.

The federal government, especially Congress, has had no consistent policy on compacts. Sometimes it has encouraged them; sometimes it has discouraged them. Because interstate compacts are a means by which states retain some control over some of their activities, this vacillation reflects the national government's uncertainty about the appropriate scope of its own power and the role of the states in an ever changing federal system.


Council on State Governments. Interstate Compacts and Agencies. Lexington, Ky.: The Council of State Governments, 1983.

Council on State Governments. Interstate Compacts, 1783–1977: A Revised Compilation. Lexington, Ky.: The Council of State Governments, 1977.

Florestano, Patricia S. "Past and Present Utilization of Interstate Compacts in the United States." Publius 24, no. 4 (1994): 13–25.

Ridgeway, Marian E. Interstate Compacts: A Question of Federalism. Carbondale: Southern Illinois University Press, 1971.

George C. S.Benson/c. p.

See alsoPort Authority of New York and New Jersey ; State Sovereignty .

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