Proposal for Lake Ontario and St. Lawrence River Regulation

Background on the Process

Regulation of water levels and flows


In 1952, the Governments of Canada and the United States applied to the IJC to construct the Moses Saunders Dam, which spans the width of the St. Lawrence River between Cornwall, Ontario and Massena, New York, in order to produce hydropower and permit larger ships to navigate between Montreal and Lake Ontario. The flow of water from Lake Ontario through the St. Lawrence River has been regulated by that project since 1960.

A 1952 Order of Approval ("Order") issued by the  Commission authorized the construction of the dam subject to certain conditions to assure compliance with the Boundary Waters Treaty.  In 1952, the two federal governments also asked the Commission to develop criteria for regulating the flows through the dam that would reduce extreme water levels mainly on Lake Ontario and flows that result from natural variations in water supplies.  The IJC developed regulation criteria and published them in a supplemental 1956 Order.   The criteria specified the maximum and minimum water levels on Lake Ontario to be respected, and a number of maximum and minimum limitations on the flows in the St. Lawrence River, provided that the water supplies to Lake Ontario were within the historical (1860-1954) range used to design the project.      

The set of rules for regulating flows is called a regulation plan.  To be accepted by the Commission, a regulation plan must meet the criteria given in the Order of Approval.  There have been several regulation plans over the history of the project. The current regulation plan was developed 50 years ago and is called 1958D Criterion of the 1956 Order provides direction to the Commission’s International St Lawrence River Board of Control to deviate from the regulation plan when water coming into the system is outside the 1860-1954 supply range.  Additional discretionary deviations from the regulation plan are also made on an ad hoc basis when it is possible to provide benefits to one or more interests without appreciable adverse effects to others.  In the last few decades, many of the weekly release decisions have deviated from the regulation plan release. The name "1958D with deviations" or "1958DD" for short, refers to the release rules as practiced, including regulation plan releases and deviations.

From 1960 until today, the regulation of the flows has reduced flooding and erosion around Lake Ontario, reduced flooding near Montreal, provided improved navigation conditions at Montreal and through the St. Lawrence Seaway, and provided more favorable summer water levels for boating on Lake Ontario and the St. Lawrence River when compared to pre-regulation conditions.  Further investigation by the Commission into Great Lake water level fluctuations in the 1990s suggested that a detailed study was advisable to understand and improve water level regulation practices for Lake Ontario-St. Lawrence River.   The Governments accepted the Commission’s recommendation and funded a binational five year study of the Lake Ontario and St. Lawrence River system.

Towards a new regulation plan

In 2000, the Commission established the International Lake Ontario – St. Lawrence River Study Board to provide options for regulating Lake Ontario that would address environmental concerns, improve the benefits of regulation, and assure that the regulation plan would work over a broader range of climate conditions.  In 2006, the Study Board issued a report with three options: Plan A+, Plan B+, and Plan D+. The Study Board’s report concluded, and the Commission agreed, that while regulation since 1960 had provided benefits, it also had degraded the coastal wetlands ecosystems of Lake Ontario and the upper St. Lawrence River.  These wetlands provide critical habitat for the fish and wildlife.  The Commission recognizes that significant actions have been taken in both countries to improve ecosystems of Lake Ontario and the St Lawrence River. However, the regulation of water levels has resulted in a loss of biological diversity in the coastal wetlands of Lake Ontario and the upper St. Lawrence River that can only be restored by changing the way water levels are regulated.

In the summer of 2008, the Commission held hearings on a new regulation plan called Plan 2007 and a proposed revised Order of Approval. Plan 2007 was a variation on Plan D+.  It captured some of the environmental benefits of Plan B+ (a more environmentally friendly plan) while preserving the protection against flooding and erosion that shoreline property owners have under 1958D with deviations.  The Commission found virtually no support for the proposal.  New York State, the Province of Ontario, environmentalists and many others favored Plan B+.  The Province of Quebec and other downstream interests favored more precaution regarding expected impacts on the lower St. Lawrence River.  Many homeowners on Lake Ontario wanted to keep the target four foot range of water levels in the 1956 Order.  

Developing the proposal 

The Commission withdrew Plan 2007, went back to work, and asked an informal ad hoc working group made up of officials from the U.S. and Canadian federal governments and the New York, Quebec and Ontario governments to provide advice to the Commission on a new approach to regulation.  The working group used the research, assessment tools and public input from the Study Board’s report, comments from the Commission hearings on Plan 2007, and additional analyses carried out by a wide array of experts from within and outside the jurisdictions.

In 2012, the Commission invited public comments on a proposed new approach that included a regulation plan called"Bv7" (the name signifying it was version seven in a series of modifications to Plan B+). The Commission held 12 information sessions and hosted a four day web-based dialogue that allowed people to ask questions and provide information and opinions to a panel of regulation plan experts.  Unlike Plan 2007, Bv7 was supported by many, but there were also many who voiced their opposition.  Particularly among property owners along the south shore of Lake Ontario there was concern about the slightly increased risk they would face under Bv7. 

The Commission and the ad hoc working group continued through the rest of 2012 to refine the new regulation plan to preserve the environmental benefits that had broad public support and reduce the negative impacts on the south shore of Lake Ontario.

Following over four years of work, including consultations with stakeholders in the basin, discussions with aboriginal Tribes and First Nations, public meetings and input from the U.S. and Canadian federal governments and New York, Quebec and Ontario, Commissioners have agreed to conduct public hearings and solicit public comment on a new proposal for Lake Ontario and the St. Lawrence River regulation, which includes (1) a regulation plan, (2) an Order, (3) a Board, (4) a policy on deviations and (5) an adaptive management strategy.