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GLIN==> Lake Ontario Regulation

Submitted by John W. Kangas <John.W.Kangas@usace.army.mil>

Lake Ontario Regulation
International St. Lawrence River Board of Control


Lake Ontario Outflow Strategy
May 14, 2004

The International St. Lawrence River Board of Control (Board) met on May 12
to discuss current and anticipated conditions, as well as operations since
end of April, and decided to adopt the following strategy beginning May
15th.  Outflows will be as determined by Regulation Plan 1958-D, except for
the following deviations to meet critical needs or to prevent flooding in
the Montreal area.

A. The outflow may be increased to meet critical hydropower needs, to
maintain levels above 20.6 m (67.6 ft) at Pointe-Claire on Lake St. Louis,
or to allow incoming vessels to reach the Port of Montreal. Any such
over-discharges shall be limited to no more than 600 cubic metres per second
(cms) (24,600 cubic feet per second (cfs)) per day and 300 cms (12,300 cfs)
per week.

B. The outflow may be decreased as necessary to prevent the level of Lake
St. Louis from exceeding 22.10 m (72.5 ft).

The Board considered the following factors (among others) in its strategy

- On May 11, Lakes Superior, Michigan-Huron and Erie were 15 cm (6 inches),
41 cm  (16 inches) and 8 cm (3 inches) below average, respectively.  They
are expected to remain below average throughout the next 6 months.

- On May 11, Lake Ontario was at elevation 75.01 m (246.1 ft).  This was 2
cm (1 inch) above average and 12 cm (5 inches) above last year.  This level
is also 36 cm (14 inches) below the upper regulation limit, and 86 cm (34
inches) above the lower regulation limit that applies during the navigation

- Lake Ontario is still slowly rising.  It is expected to rise to about
75.04 m (246.2 ft) in June.  The June level would then be about the same as
average and 33 cm (13 inches) below the upper regulation limit.  If very wet
or very dry conditions prevail, June's water level could be 75.14 m (246.5
ft) or 74.96 m (245.9 ft), respectively.  The risk of exceeding the upper
regulation limit is estimated to be about 1%, if the regulation plan is
strictly followed.  The risk of exceeding the lower regulation limit this
year is estimated to be about 5%.

- Downstream conditions were noted: Lake St. Louis is very near its average
level and 85 cm (33 inches) above last year; Montreal Harbour is 18 cm (7
inches) below average and 138 cm (54 inches) above last year. Ottawa River
reservoirs are filling more quickly than average. The freshet is still

- The total accumulated water on Lake Ontario relative to the Plan 1958-D
level is now about 4 cm (1.5 inches).

The Board, in conjunction with its staff, will continue to monitor the
situation and act accordingly.  This information can also be found on the
Board web site (see below) and will be updated as required.

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, such as the international hydropower project at Massena,
New York and Cornwall, Ontario.  When 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 countries.  For more
information, visit the Commission's website at www.ijc.org.

The International St. Lawrence River Board of Control was established by the
International Joint Commission, mainly to ensure that outflows from Lake
Ontario meet the requirements of the Commission's Orders of Approval.  For
more information, visit the Board's website at www.islrbc.org.

For Release: May 14, 2004

John Kangas, Chicago, Illinois              (312) 353-4333
Reg Golding, Ottawa, Ontario               (613) 998-1408

John W Kangas
(312) 353-4333

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