Gros Ventre Tribe, Assiniboine Tribe


Fort Belknap Indian Community of the Fort Belknap Reservation of Montana


Fort Belknap Indian Water Rights Settlement


Fort Belknap Indian Reservation




Missouri River Basin

Document Type

Settlement Agreement and State Legislation



Publication Date



Settlement & State Legislation: No separate settlement agreement. Fort Belknap-Montana compact ratified. (MCA 85-20-1001) (April 16, 2001) Parties: Gros Ventre and Assiniboine Tribes of the Fort Belknap Reservation, MT and US. The Tribes have right to 645 c/f/s from the Milk River and its tributaries upstream from Reservation diversion point with a priority date of October 17, 1855. Off-stream storage is limited to 60,000 a/f and up to 125 c/f/s is for irrigation and other historical purposes. Tribes have right to develop surface water in the Milk River Basin for livestock impoundments provided they don't use more than 30 a/f/y. Tribes have rights to surface water and its hydrologically connected groundwater in the Peoples Creek Basin; water may also be stored if kept within the Reservation; surface water is also available for livestock impoundments. Tribes have right to 8,024 a/f/y in surface of Beaver Creek Basin and groundwater hydrologically connected to surface for irrigation use. Tribes have right to water in the Missouri River Basin for non-irrigation purposes and may develop surface water for livestock (max 30 a/f/y impoundments.) Tribes have the following rights to off-reservation trust and fee lands in the Missouri and Peoples Creek Basins: 1,135 a/f/y for irrigation (priority date July 24, 1893), 1,290 a/f/y for conveyance to Peoples Creek Basin (priority date Jan 1, 1935), non-irrigation purposes that existed prior to the effective date of the Compact, and livestock purposes. They may also use hydrologically connected groundwater and develop wells that do not exceed 10 a/f/y. An undetermined amount of Lake Elwell water is allotted subject to the rights of other tribes. The Tribes shall adopt a Tribal water code and administer the Tribal Water Right.

The Act provides administrative procedures for certain activities, requires reporting and sets up management committees. Montana will administer state law rights on reservation. The BIA administers the Right once it is in the Fort Belknap Indian Irrigation Project. There will be cooperative management in a controlled groundwater area. A Milk River Watershed Improvement Trust is established to generate interest funds to improve water quality and habitat in the Milk River Basin. All parties agree to work with the USA, Blackfeet Tribe and Milk River Project to restore the St. Mary Diversion facilities, which are essential to this Compact. If Congress does not ratify this Compact within five years, the Tribes may withdraw. Tribes waive rights to any other water. [Source:]


MT State Legislation ratifying Compact: 46 pages.

Permanent URL

Fort_Belknap_Compact_Appx.1_Proposed_Decree.pdf (81 kB)
Appx. 1, Proposed Decree

Fort_Belknap_Compact_Appx.2_Reservation_Map.pdf (3109 kB)
Appx. 2, Basin Map

Fort_Belknap_Compact_Appx._3_Peoples_Creek_Stips.pdf (59 kB)
Appx. 3, Peoples Creek Stipulations Basin 40I

Fort_Belknap_Compact_Appx.4_Flow.pdf (8 kB)
Appx. 4, Flow Calculations

Fort_Belknap_Compact_Appx.5_Criteria_for_Evaluation.pdf (9 kB)
Appx. 5, Criteria for Evaluation

2017-01-24_FortBelknap_FactSheet_updated_JH.pdf (20 kB)
MT DNRCC Summary

Fort_Belknap_Compact_Map.pdf (9392 kB)
Ft. Belknap Compact Map


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