In 1958, Queen Elizabeth II and Vice President Richard Nixon officially opened the Moses-Saunders Power Dam in the St. Lawrence River between northern New York State and eastern Ontario. The ceremony marked the culmination of a proposal developed in 1951 both to generate power from the river and to develop the waterway to enable shipping from the Great Lakes to the Atlantic.

The project marked a unique partnership between Canada and the US to develop shared waters and do it in a way that both countries would benefit. In the early history of Canada and the US, the waters of the Great Lakes and the St. Lawrence represented the greatest part of the border between the two countries. Over the course of almost 150 years a series of treaties – initially between Britain and the US and subsequently between Canada and the US – moved the relationship from de-armament to close cooperation.

The Rush-Bagot Treaty of 1818 was intended to de-militarize the Great Lakes. The Treaty of Washington in 1871 resolved a number of outstanding disputes, including fisheries on the Great Lakes, between the US and Britain, arising from British support for the Confederacy during the Civil War. Finally, in 1909, Canada and the US concluded the Boundary Waters Treaty to enable joint management of the shared waters. The Treaty established the International Joint Commission, which today oversees the power dam and the St. Lawrence Seaway.

The framework of those historic agreements between the United States and what came to be Canada was the basis of the construction of the St. Lawrence Seaway and the Moses-Saunders Power Dam. The dam was built between 1954 and 1958 and straddles the Canada-US border in the middle of the St. Lawrence River. It provides 912 MW of power to New York State and 1,045 MW to Ontario. Canadian and American authorities divide management of the facilities between them.

The Moses-Saunders Power Dam is by no means unique in the North American energy sector. In addition to shared generating facilities, Canada supplies the United States with substantial electricity exports. In the period 2019 to 2024, according to the Canadian Energy Regulator (CER), net exports were as much as 57.9 TWh/yr. It is a trade that balances demand and supply in both countries.

That trade is replicated elsewhere in the Canadian energy sector. The CER reports that between 2019 and 2024, Canada exported 490 million cubic metres per day (3.1 million barrels per day) of heavy crude and 126 million cubic metres per day (0.8 million barrels per day) of light crude. Much of the heavy crude is exported to US refineries that were designed or re-fitted specifically to take Canadian crude oil.

None of these observations will be news to anyone with knowledge of the Canadian energy sector. It is characteristic of Canadian industries that they are coordinated or integrated with US industries. The countries have served as a model of how two independent economies can function closely together to benefit both nations.

The assumptions underlying that coordination have recently been called into question by the US administration. These will be challenging – and possibly painful – times until a new arrangement can be settled. However, it is difficult to envision a new structural arrangement that would increase the mutual benefits beyond those which our two countries have enjoyed historically.