Mni Wiconi Act Amendments of 1994

Mni Wiconi Act Amendments of 1994 - Amends the Mni Wiconi Project Act of 1988 to: (1) include within its purposes the provision of a sufficient water supply to the Rosebud and Lower Brule Indian Reservations in South Dakota; (2) require the Oglala Sioux rural water supply system to include facilities which allow for interconnections with the Rosebud and Lower Brule water systems; (3) direct the Secretary of the Interior to plan, design, construct, operate, maintain, and replace the Rosebud Sioux and Lower Brule Sioux rural water systems consisting of appropriate pumping and treatment facilities, pipelines, and related equipment; (4) require cooperative agreements with non-Federal entities for such systems (with specified agreement and construction requirements); (5) authorize the Secretary to interconnect the Lyman-Jones and West River rural water systems with the other systems authorized under such Act and to provide for the delivery of water to such systems from the Missouri River through common facilities of the Oglala, Rosebud, and Lower Brule water systems; and (6) subject the Rosebud and Lower Brule Sioux water supply systems to certain requirements of such Act regarding mitigation of fish and wildlife losses during any required construction.

Subjects the Rosebud and Lower Brule water supply systems to a prohibition on the use of funds for irrigation purposes.

Authorizes the Rosebud, Lower Brule, West River, and Lyman-Jones water supply systems to utilize power from the Pick-Sloan power supply system for appropriate purposes. Authorizes appropriations for the: (1) Oglala, Rosebud, and Lower Brule Sioux, West River, and Lyman-Jones rural water supply systems; and (2) waste water disposal system feasibility studies required under such Act.

Specifies that the operation and maintenance expenses associated with water deliveries to the West River and Lyman-Jones Rural Water Systems are a non-Federal responsibility and for such deliveries the Secretary shall contract with the West River and Lyman-Jones Systems for the payment of an annual operation and maintenance fee, based on the incremental operation and maintenance costs for water actually delivered each year to such Systems. Requires such operation and maintenance payments to be increased or decreased by such amounts as may be justified by reason of ordinary fluctuations as indicated by indices applicable to comparable regional rural water supply systems for the type of operation and maintenance involved.

Applies certain water rights provisions under such Act to the Rosebud and Lower Brule Sioux rural water supply systems.

Authorizes and directs the Secretary to conduct and report to the Congress on waste water disposal facility feasibility studies on the Pine Ridge, Rosebud, and Lower Brule Indian Reservations.