McCarran Amendment

The McCarran Amendment, 43 U.S.C. § 666 (1952) is a federal law enacted by the United States Congress in 1952 which waives the United States' sovereign immunity in suits concerning ownership or management of water rights. It amended Chapter 15 (Appropriation of Waters; Reservoir Sites) of Title 43 (Public Lands) of the United States Code. The McCarran Amendment gives others the right to join in such a lawsuit as a defendant. Prior to the Amendment, sovereign immunity kept the United States from being joined in any suits. The Amendment enabled suits concerning federal water rights to be tried in state courts.

(a) Joinder of United States as defendant; costs consent is given to join the United States as a defendant in any suit

(1) for the adjudication of rights to the use of water of a river system or other source, or

(2) for the administration of such rights, where it appears that the United States is the owner of or is in the process of acquiring water rights by appropriation under State law, by purchase, by exchange, or otherwise, and the United States is a necessary party to such suit. The United States, when a party to any such suit, shall

(1) be deemed to have waived any right to plead that the State laws are inapplicable or that the United States is not amenable thereto by reason of its sovereignty, and

(2) shall be subject to the judgments, orders, and decrees of the court having jurisdiction, and may obtain review thereof, in the same manner and to the same extent as a private individual under like circumstances: Provided, That no judgment for costs shall be entered against the United States in any such suit.

(b) Service of summons Summons or other process in any such suit shall be served upon the Attorney General or his designated representative.

(c) Joinder in suits involving use of interstate streams by State Nothing in this section shall be construed as authorizing the joinder of the United States in any suit or controversy in the Supreme Court of the United States involving the right of States to the use of the water of any interstate stream.

While the original amendment specified that state courts only held concurrent jurisdiction in state and federal district courts in water rights adjudication cases under the McCarran Act, the case Colorado River Water Conservation District v. United States, 424 U.S. 800 (1976) specified that all water rights adjudication cases must originate in state court, though they can be appealed later to federal courts.

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