The Northern Montana Water Security Act of 2025 aims to finalize the long-standing water rights claims of the Fort Belknap Indian Community (FBIC) and the United States, acting as trustee for the Community, within Montana. It officially ratifies and confirms the Fort Belknap-Montana water rights compact, directing the Secretary of the Interior to execute it and take necessary implementation actions. The legislation also authorizes substantial funding and facilitates the exchange and transfer of various federal and state lands to the FBIC.

Central to the settlement, the bill confirms the FBIC's Tribal water rights, held in trust by the United States, ensuring they are not subject to loss through non-use. It guarantees that benefits for allottees will be equivalent to or exceed their existing rights. The FBIC is granted authority to allocate, distribute, and lease these water rights both on and off the Reservation, subject to a future Tribal water code and Secretarial approval or tribal regulations. Additionally, the Community will receive favorable power rates for its irrigation projects.

Significant land provisions are included, authorizing the exchange of federal lands for specific state-owned parcels, which will then be taken into trust for the FBIC. Further, numerous federal lands currently managed by the Bureau of Land Management and the Bureau of Indian Affairs will be transferred into trust for the Community. Approximately 2,500 acres of Dodson Land, under Bureau of Reclamation jurisdiction, will also be taken into trust, subject to a perpetual easement for Milk River Project operations. All lands taken into trust under this Act are explicitly prohibited from being used for gaming.

The Act allocates 20,000 acre-feet of water annually from Lake Elwell to the FBIC for any beneficial purpose, with associated costs deemed non-reimbursable. It mandates significant federal investment in water infrastructure, including up to $300 million for Milk River Project mitigation, specifically for restoring the St. Mary Canal and enlarging the Dodson South Canal. Another $415.8 million is allocated for the rehabilitation, modernization, and expansion of the Fort Belknap Indian Irrigation Project System, with these costs also being non-reimbursable.

To manage the financial aspects, the bill establishes the Aaniiih Nakoda Settlement Trust Fund for the FBIC, comprising three distinct accounts for irrigation development, water resources administration, and clean domestic water/sewer systems. A separate Fort Belknap Indian Community Water Settlement Implementation Fund is created for the Secretary to manage the Milk River Project mitigation and the FBIC Irrigation Project. Total authorized and mandated appropriations for these funds exceed $1.1 billion, subject to cost adjustments.

The settlement involves comprehensive waivers and releases of past water rights claims by the FBIC and the United States as trustee, in exchange for the benefits provided. However, certain rights are expressly reserved, such as the enforcement of recognized water rights and claims related to water quality. The effectiveness of the settlement hinges on an enforceability date, triggered by conditions including FBIC approval, court approval of the compact, full appropriation of funds, and execution of waivers. If these conditions are not met by specified deadlines, the title expires, and waivers become void.

Beyond the Fort Belknap settlement, the bill also authorizes a significant appropriation of $250 million for the Blackfeet Tribe. These funds are designated for the planning, design, construction, operation, maintenance, and replacement of community water distribution and wastewater treatment facilities for the Blackfeet Indian Reservation of Montana.