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16 U.S. Code § 410fff–8 - Water rights

(a) Effect on water rightsNothing in this subchapter shall—
(1)
constitute an express or implied reservation of water for any purpose; or
(2)
affect any water rights in existence prior to October 21, 1999, including any water rights held by the United States.
(b) Additional water rights

Any new water right that the Secretary determines is necessary for the purposes of this subchapter shall be established in accordance with the procedural and substantive requirements of the laws of the State of Colorado.