News Releases

Federal water managers announce public information sessions about post-September 2024 Columbia River Treaty operations

Northwestern Division, USACE
Published Sept. 20, 2023
Lush greenery of the treelined foothills along the Columbia River bisect a near cloudless blue sky from the curves of the Columbia River gorge. The scrub along the floodplain is a lighter green where the sunlight shines brighter on the vegetation. In the distance, the horizon begins to gray as the river curves and the foothills appear to close the gap along the river's curves.

Looking east along the Columbia River Gorge from the Vista House in Oregon. The Columbia River Treaty is an international agreement between the United States and Canada, signed in 1961 that establishes coordination obligations between the countries for flood risk management, hydroelectric energy production and has yielded environmental benefits in the Columbia River Basin.

How the United States uses reservoir space in Canada changes on September 16, 2024, from the high degree of structure and control of flows coming across the border from Canada experienced over the last 60 years under the Columbia River Treaty, to an operation that increases the uncertainty of those flows. The U.S. Army Corps of Engineers (USACE) and Bureau of Reclamation (Reclamation) will hold four virtual public information sessions in September and October to begin informing the public about the potential changes.

USACE and Reclamation operate and maintain 14 dams in the Columbia River System and continue to work as part of the U.S. negotiating team to negotiate a modernized Treaty regime with Canada. If Canada and the United States can reach agreement to modernize the Treaty regime, it could reduce the uncertainty of this September 2024 change. However, USACE and Reclamation will be prepared to operate regardless of the outcome of negotiations.

Absent modernization, the treaty will no longer require Canada and the United States to coordinate for flood risk management as we have for the first 60 years of the Treaty. The United States’ ability to “call upon” Canadian storage when needed does not expire and continues so long as Canada has dams in the basin that contribute to flood risk reduction in the United States.

While the United States can call on Canada for space during real-time operations, it is unknown how Canada will react, and it is unclear how Canada will operate its reservoirs after September 2024. One potential result is less predictability of managing runoff from Canada to better protect the United States from flooding, because the United States does not have additional reservoir space to offset the loss of assured water storage space in Canadian Treaty reservoirs. This will potentially result in changes affecting various stakeholders across the region; although, the extent of those changes is unclear at this point.

However, water managers do not anticipate increasing flood risk in the United States because of existing rights to call upon Canadian reservoirs under the Treaty and our ability to operate Lake Roosevelt consistent with current operating rules. Lake Roosevelt is likely to experience lower lake elevations more often in the winter and spring. Related U.S. dams in the Columbia River Basin already have rules in place that maximize the storage space available for flood risk management regardless of potential changes related to operational uncertainty in Canada. USACE and Reclamation will continue operating projects for water supply, navigation, fish and wildlife, and other purposes.   

Federal planners will hold four virtual public information sessions in September and October to provide information to the public. These sessions will be informational in nature and presenters will not take questions. For more Real-Time Flood Risk Management information, visit:


Virtual meeting information:

Dates: Wednesday, Sept. 27: 12-1 p.m. PST and 5-6 p.m. PST

Tuesday, Oct. 10: 11 a.m. – 12 p.m. PST and 5-6 p.m. PST


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

Access Code: 1998 73 5911#

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Tom Conning
971-276-8763 (cell)

Release no. 23-034