Columbia River Treaty

The United States and Canada began negotiations in May 2018 with the objective of developing a modernized Columbia River Treaty regime that serves the people of the Columbia River Basin on both sides of the border, including members of several Tribal and Indigenous Nations.

The U.S. Department of State is leading the U.S. team in negotiations with Canada. The U.S. Government’s key objectives include continued, careful management of flood risk; ensuring a reliable and economical power supply; and improving the ecosystem in a modernized Treaty regime.

Discussions with Canada have focused on water flowing across the border, namely from the Canadian Treaty projects—Keenleyside (also known as Arrow), Duncan and Mica dams—and from Libby Dam in the United States. These projects together are collectively known as the “Treaty Projects.”

On July 11, 2024, the United States and Canada announced an agreement in principle, which can be found on the Department of State's website: https://www.state.gov/summary-of-the-agreement-in-principle-to-modernize-the-columbia-river-treaty-regime/. 

The Treaty provisions regarding Canada’s obligations to operate its reservoirs for U.S. flood risk management changed on September 16, 2024. The United States secured an obligation from Canada to provide a degree of flood risk management when the Treaty was originally signed, that obligation continues so long as Canada has dams in the basin that contribute to flood risk reduction in the United States. The first 60 years of that obligation were handled on a pre-planned and pre-paid basis. In 2024, the 60 years of pre-planned flood storage in the Canadian Treaty was replaced with terms that allow the United States and Canada to coordinate FRM operations and payment for FRM differently, by using what is known as "Called Upon" or “real-time” operations.

This provision means that the United States can call upon Canada for assistance when necessary to meet U.S. flood risk management needs. The United States would need to continue to operate its reservoirs to reduce flood peaks in periods when it calls on Canadian reservoir storage, as it does today. The Treaty has a corresponding change on the payment side, which would require the United States to compensate Canada based on the economic loss shown to arise directly from any foregone use of the relevant reservoir space during the flood period.

Since the July 11, 2024 agreement in principle, both countries have begun developing text for a modernized treaty regime. Once the agreement enters into force, it improves FRM operations for the United States over the existing Treaty as it provides for 3.6 million acre-feet (MAF) of preplanned space in Canadian reservoirs. Until that new regime enters into force, the United States and Canada will be in an interim period, prompting the need for a new operating plan for FRM. USACE has worked with Canada to secure the 3.6 MAF of preplanned FRM storage for 2025.

For the first 60 years of the Treaty the United States paid up front for a preplanned amount of FRM storage in Canadian reservoirs, which helped manage floods in the Columbia River. As of September 16, 2024, the operations under the Treaty for that preplanned space in Canada are no longer in force. Under the existing Treaty, the United States can continue accessing storage space in Canada for FRM after September 2024, but the access will look different than the first 60 years of the Treaty. The U.S. Army Corps of Engineers and the Bureau of Reclamation must continue operating and maintaining federal projects to meet all Congressionally authorized responsibilities. The U.S. Government is prepared to, and if needed, will implement real-time flood risk management (FRM) operations. We will also work with the stakeholders and Tribes who rely on the Columbia River System (CRS) on any potential changes in flows across the border from Canada.

Until that new Treaty regime enters into force, the United States and Canada will be in an interim period, prompting the need for a new operating plan for FRM. USACE has worked with Canada to secure the 3.6 MAF of preplanned FRM storage for 2025.

The 2025 planned operations include Canada providing 3.6 MAF of preplanned FRM storage at Hugh Keenleyside Dam, which is consistent with the July agreement in principle. If U.S. FRM reservoirs and the 3.6 MAF of preplanned space in Canada are insufficient to address U.S. flooding, the U.S. will exercise its right to “call” Canada for additional space under the Columbia River Treaty.

USACE and Reclamation will explain the potential changes to river flows and reservoir storage under this new dynamic. The agencies are holding the public information sessions virtually and will provide information about potential impacts to operations.

Virtual meeting information:

Dates: Wednesday, December 4: 10 to 11 a.m. PST

Thursday, December 5: 4 to 5 p.m. PST

Link: https://usace1.webex.com/meet/edward.t.conning

Call: 1-844-800-2712 (US) (Call-in toll-free number)

Access Code: 1998 73 5911#

USACE and Reclamation held virtual public information sessions in 2023 to provide information to the public.

Flood risk is a combination of the likelihood of a natural or man-made flood hazard happening and the consequences or impact if it occurred. For more information on flood risk please see our flood risk management page.

Learn more about Real-Time Flood Risk Management.