For Release: February 3, 1998
International Joint Commission Seeks Relief for
Shoreline Communities in Setting Lake Ontario-St. Lawrence River Flows
The International Joint Commission today invoked criterion (k) of its Orders of Approval for
Lake Ontario-St. Lawrence River regulation based on high water supplies to Lake Ontario and a
recommendation by its International St. Lawrence River Board of Control.
Under high water supply conditions, criterion (k) gives precedence to shoreline property owners
on Lake Ontario and the St. Lawrence River from the Thousand Islands to past Montreal when
setting flows through the international hydropower project at Massena, New York and Cornwall,
The Board of Control's recommendation was based on the determination that water "supplies of
the past, as adjusted" have been exceeded. Criterion (k) is an extraordinary measure that is
invoked when Lake Ontario water supplies exceed those experienced prior to 1954. Water
supplies to Lake Ontario in January 1998 were the highest January supplies on record.
Since fall, the Board of Control's strategy has been to release more water from Lake Ontario than
would have been called for under the current regulation plan, known as Plan 1958-D, whenever it
could do so without adversely affecting other interests. Though the water level of Lake Ontario is
high, it would presently be 0.56 metres (1.8 feet) higher had the project not been built.
The International St. Lawrence River Board of Control and the International Joint Commission
acted on criterion (k) at this point in time to set clear priorities and provide the authority that may
be needed to achieve them. Invoking criterion (k) has no immediate effect on flow releases,
because the Board of Control is presently setting flows that will allow a stable ice cover to form.
Forming a stable ice cover helps prevent underwater ice blockages that can restrict flows. Once
the ice cover is formed, the Board of Control will release flows as high as possible without
causing downstream flooding, as permitted under the winter operations provision of the
Commission's Orders of Approval. However, at the conclusion of winter operations, criterion (k)
provides the authority to release higher flows as necessary to achieve the specified priorities.
The level of Lake Ontario is presently at 75.02 metres (246.13 feet) above sea level (IGLD
1985), which is approximately 0.44 metres (1.4 feet) above its long term average for this time of
year. The inflow to Lake Ontario from Lake Erie will remain high for the foreseeable future
because of high water levels on Lake Erie. The outlook for the rest of the year, however, depends
on several factors and is highly uncertain. If the Board of Control were to strictly follow Plan
1958-D, Lake Ontario would peak at 75.84 metres ( 248.82 feet) at the end of June under a high
precipitation scenario or at 75.02 metres (246.13 feet) at the end of April under a low
precipitation scenario. It must be noted, however, that the Board of Control will be releasing
significantly more water than the plan calls for at every available opportunity. In addition,
projections of the peak lake level are likely to change over time. For example, projections made
just one month ago have changed dramatically because of the unusually high precipitation that
occurred during the month of January.
Water levels that will actually occur this year under criterion (k) operations will depend on
several factors, including precipitation and temperature in the Lake Ontario and St. Lawrence
River basin, the extent to which flows in the St. Lawrence River are constrained by ice
conditions, flooding conditions downstream, particularly during the spring runoff from the
Ottawa River basin, and the potential for serious adverse effects to any other interest, including
Under criterion (k), the Board of Control will continue to monitor conditions upstream and
downstream to determine the appropriate flow through the power project. The Commission and
its Board of Control will continue to carefully consider conditions on Lake Ontario and the St.
Lawrence River to determine the appropriate duration of criterion (k) operations.
The International Joint Commission was created under the Boundary Waters Treaty of 1909 to
help prevent and resolve disputes over the use of waters along the Canada-United States
boundary. Its responsibilities include approving certain projects that would change water levels
on the other side of the boundary. If it approves a project, the Commission's orders of approval
may require that flows through the project meet certain conditions to protect interests in both
The International St. Lawrence River Board of Control was established by the Commission in its
1952 Order of Approval. Its main duty is to ensure that outflows from Lake Ontario meet the
requirements of the Commission's Orders. The Board also develops regulation plans and
conducts special studies as requested by the Commission.