Northern Cheyenne Indian Reserved Water Rights Settlement Act of 1991

Northern Cheyenne Indian Reserved Water Rights Settlement Act of 1991 - Ratifies the Water Rights Compact entered into on June 11, 1991, by the Northern Cheyenne Tribe (Tribe) and Montana.

Directs the Secretary of the Interior (Secretary) to administer and enforce the Tribal water right until adoption and approval of a Tribal water code.

Requires the Secretary, through the Bureau of Indian Affairs, to assist the Tribe under existing authority in developing specified acreage in the Tongue River basin and in the Rosebud Creek basin for agricultural purposes.

Authorizes the Tribe or its authorized representatives, under specified conditions, and subject to the Secretary's approval, to enter into a service contract, lease, exchange, or other agreement providing for the delivery, use, or transfer of the water right confirmed to it in the Compact.

Directs the Secretary to identify and develop features of the Tongue River Dam Project in Montana to provide for the enhancement of fish and wildlife habitats. Authorizes appropriations for such enhancement.

Directs the Secretary to establish a Tribal Development Fund for the Northern Cheyenne Tribe to be used for: (1) land and natural resources administration, planning, and development within the Reservation; (2) land acquisition; and (3) a loan to Montana for the Tongue River Dam Project costs. Authorizes appropriations.

Authorizes the Secretary to provide certain funds to Montana for the modification of the Tongue River Dam.

Specifies contributions to be made to such project by the Tribe (as an interest-free loan to Montana) and by the State.

Authorizes appropriations for: (1) the modification of the Tongue River Dam; (2) its annual operation, maintenance, and replacement costs; and (3) all environmental compliance associated with the Compact.

States that it is the intent of the Congress that nothing in this Act shall: (1) alter the trust responsibility of the United States to the Tribe; or (2) prohibit it from seeking additional authorization or appropriation of funds for Tribal programs and purposes.

Directs the Secretary to allocate, subject to any prior reserved water rights, specified acre-feet per year of stored water in Big Horn Reservoir, Yellowtail Unit, Lower Bighorn Division, Pick-Sloan Missouri Basin Program, Montana, for use or disposition by the Tribe.

Declares that the Tribe shall not be required to make payments to the United States for the portion of the tribal water right stored in Yellowtail Reservoir unless it uses or sells the water. Specifies the schedule of such payments.

Directs the Tribe to set rates for its use or sale of stored water, and to retain all revenues from such use or sale.

Retains in the United States the right to use any and all water stored in the Big Horn Reservoir for hydropower generation.

Requires the Secretary to enter into an agreement with the Tribe providing for: (1) the Tribe's use or sale of water stored in the Big Horn Reservoir, under specified conditions; and (2) the collection and disposition of revenues in connection with water stored in it that is made available to the Tribe.

Directs the Secretary to enter into a cooperative agreement with Montana for planning, design, and construction of the Tongue River Dam Project. Retains ownership of such dam in Montana.

Expresses the intent of the Congress that nothing in this Act shall subject to the Reclamation Reform Act of 1982 any holders of State water contracts from the Tongue River Reservoir who do not have a contract for Federal reclamation storage.

Directs the Bureau of Land Management to transfer specified Federal lands in Montana to the Bureau of Indian Affairs in trust for the Northern Cheyenne Tribe. States that this transfer shall not be construed as creating a Federal reserve water right.

Directs the Secretary, acting through the Bureau of Indian Affairs, to pay to Montana, annually and on a nonreimbursable basis, an amount to cover the proportionate share of the annual operation, maintenance, and replacement costs for the Tongue River Reservoir Dam. Declares that the United States waives its immunity from suit to the extent necessary to permit with specified exceptions: (1) the resolution by the Northern Cheyenne-Montana Compact Board of matters arising within its jurisdiction; and (2) the appeal or judicial enforcement of Compact Board decisions as provided in the Compact.

Provides that nothing in this Act shall be construed to alter or amend any provision of the Yellowstone River Compact.