Rocky Boy's/North Central Montana Regional Water System Act of 2001

Rocky Boy's/North Central Montana Regional Water System Act of 2001 - (Sec. 4) Directs the Secretary of the Interior, acting through the Commissioner of Reclamation: (1) to plan, design, construct, operate, maintain, and replace the core water system for, and to operate, maintain, and replace the water distribution systems of, the Rocky Boy's Reservation in Montana; (2) at the request of the Chippewa Cree Tribe on the Reservation, to enter into a self-governance agreement with the Tribe to carry out such functions; and (3) to enter into a cooperative agreement with the North Central Montana Regional Water Authority to provide Federal funds for the planning, design, and construction of the non-core rural water system for specified Montana counties outside the Reservation.

(Sec. 6) Prohibits the Secretary: (1) from obligating funds for construction of the core or non-core system until requirements of the National Environmental Policy Act of 1969 are met and 90 days have expired since a final engineering report approved by the Secretary has been submitted to Congress; or (2) in providing for water delivery to the non-core system, from diminishing the 10,000 acre-feet per year of water stored for the Tribe pursuant to the Chippewa Cree Tribe of The Rocky Boy's Reservation Indian Reserved Water Rights Settlement and Water Supply Enhancement Act of 1999.

(Sec. 9) Directs the Secretary to authorize and provide for the use of power from the Pick-Sloan Eastern Division to start up and operate such water systems.

(Sec. 10) Requires the Tribe and the Authority to develop a water conservation plan that contains: (1) a description of water conservation objectives and appropriate water conservation measures; and (2) a time schedule for implementing the measures to meet the objectives.

(Sec. 12) Authorizes appropriations.