International Joint Commission  

In 1909 Canada and the United States signed the Boundary Waters Treaty and established the formation of the six member International Joint Commission (IJC) to oversee issues concerning boundary and transboundary waters shared by the two countries, including the Great Lakes.

When the IJC approves projects such as hydro-electric dams, it issues Orders of Approval that govern the regulation and operation of the projects.  It approved construction of the hydro-dams on the St. Lawrence River in 1952 as part of the St. Lawrence Seaway and issued associated Orders of Approval.  In 1956 it amended its Orders of Approval for the dam projects to include regulation criteria for water levels.

Since 1960, the water levels in Lake Ontario and the St. Lawrence River have been regulated by the structures built during the development of the St. Lawrence Seaway. The Moses-Saunders Power Dam between Cornwall, Ontario and Massena, NY is the principal regulatory structure.  

A second dam at Long Sault, Ontario acts as a spillway when outflows from Lake Ontario are larger than the capacity of the power dam. The third dam at Iroquois, Ont. can also be used to regulate the flow but is primarily intended to assist in the formation of a stable ice cover in the early winter as well as to ensure water levels in Lake St. Lawrence, upstream of the Moses-Saunders Power Dam, do not rise too high.  

One of the primary conditions of the IJC’s Orders of Approval is that water levels in Lake Ontario be regulated between 243.29 and 247.29 feet or 74.15 and 75.37 meters. This represents a maximum fluctuation of four feet. Prior to the construction of the seaway, water levels fluctuated approximately six feet.

Contact information for the United States and Canadian IJC offices as well as the complete text of the 1909 Boundary Waters Treaty may be found on the IJC web site at www.ijc.org

 International St. Lawrence River Board of Control

Under its Orders of Approval the IJC established the International St. Lawrence River Board of Control (ISLRBC) to ensure that the conditions and criteria in the Orders are met. This board consists of a total of ten members from the U.S. Army Corps of Engineers, Transport Canada, Environment Canada and five other state, provincial and local agencies and representatives.

The International St. Lawrence River Board of Control current plan is known as 1958-D.

Plan 1958-D contains an emergency criterion called Criterion K in which it states that in the event water supplies exceed supplies of the past, the works in the international section should be operated to provide all possible relief to riparian owners upstream and downstream. It also states that if water supplies are lower than in the past, the works should be operated to provide all possible relief to navigation and power interests.

Their only purpose is to let enough water out at the dam to comply with IJC’s requirements.  The regulation plan does not recognize the following interests: recreational boating, native people, agriculture, tourism, wetland and shore habitat, water quality and fisheries.

For more information on the Board of Control, you may visit their web site at www.islrbc.org.