IJC releases report on Peaking and Ponding in St. Marys River and invites comment on proposed decision


The International Joint Commission (IJC) has released today the technical report of its International Lake Superior Board of Control (the Board) onpeaking and ponding in the St. Marys River. The Board's report recommends that the IJC extend the authority to conduct peaking and ponding operations for one year so that further operational experience can be evaluated and further study conducted. The IJC proposes acting on this recommendation, and invites the public to comment by March 14, 2002, before it makes a decision on this matter.

Peaking and ponding operations are carried out by the Edison Sault Electric Company and Great Lakes Power Limited to store water during times of off-peak demand and increase hydroelectric power generation during times of on-peak demand. Peaking is the variation of hourly flows within the daily average flow while ponding is the variation of daily flows within the weekly average flow (i.e. higher weekday flows and lower weekend flows).

The two power entities are authorized to use water from the St. Marys River by the IJC's Orders of Approval, which contain provisions to protect interests in both countries that may be affected by changes in natural water levels and flows. Outflows from Lake Superior are set on a monthly basis by the IJC-approved regulation plan, Plan 1977A, under the oversight of the IJC's Board. The current low water situation has drawn the IJC's attention to the conduct of peaking and ponding operations in the St. Marys River. The IJC has provided temporary authority to the power entities to conduct peaking and ponding operations until March 20, 2002, under the supervision of the Board. The IJC conducted public hearings on this issue in Sault Ste. Marie Michigan and Ontario on January 28th, 2002, and asked its Board to prepare a report by February 28, 2002.

Board's Finding 
The Board consulted with various interest groups and analyzed readily available data. It determined that peaking and ponding operations cause water levels at the U.S. Slip (immediately downstream of the locks) to fluctuate by about 16 centimeters (6.3 inches) for a 1,000 cubic meter per second.

(35,000 cubic feet per second) change in flow. Water level impacts dissipate as one proceeds further downstream and are negligible at Rock Cut, near the mouth of the St. Marys River. Water level impacts also dissipate towards Garden River in the North Channel. Peaking and ponding operations were found to have negligible impact on water levels upstream of Sault Ste. Marie. Other factors affecting water levels in the river, such as winds, barometric pressure changes, and Lake Huron water levels, while not studied separately, together cause a fluctuation of about plus or minus 6 centimeters (2.4 inches) during the day at the U.S. Slip.

Peaking and ponding operations enable efficient use of water for generating hydropower. The high flows caused by the daily peaking cycle can be beneficial to navigation but, under certain conditions, sustained low weekend flows caused by ponding operations could be detrimental to navigation. The views and comments collected by the board did not identify any known adverse environmental or other impacts.

Based on these considerations and its analysis of data from the past four years, the Board recommended to the IJC that peaking and ponding operations be allowed to continue for an additional year subject to certain guidelines. During the year, the Board would monitor water levels, review peaking and ponding operations as conducted by the power entities, and record and assess any impacts that might arise from peaking and ponding operations. At the end of the year, the Board would provide a further report to the IJC.

The report on peaking and ponding may be downloaded from the Board's website.

The Board will conduct a public briefing by telephone conference call at 2:00 p.m. (Eastern time) on March 11, 2002 to provide information on its report and to receive public comment. Anyone who is interested in the report is invited to participate in the call. Please contact one of the Board Secretaries for information on how to participate in the call:

Mr. John W. Kangas 
Phone: (312) 353-4333 
Fax: (312) 353-3138  Mr. Peter Yee 
Phone: (613) 938-5725 
Fax (613) 937-1302 

Proposed IJC decision

Taking into account the guidelines recommended by its Board, the IJC proposes providing the following authority to the power entities to conduct peaking and ponding operations for an additional year.


Until March 20, 2003, the power entities may conduct peaking and ponding operations under the supervision of the International Lake Superior Board of Control. Such operations shall be subject to prior approval from the Board at the beginning of each month and shall be conducted in a manner consistent with the mode of operation outlined in the power entities’ February 8, 2002, submission to the IJC. The power entities shall coordinate peaking and ponding schedules with Board representatives at the beginning of each month. At the beginning of the month, the Board may suspend ponding operations for the month, or a portion thereof, if it expects that ponding operations would result in sustained weekend levels at the U.S. Slip Gauge declining below chart datum elevation. The Board may also alter or suspend peaking or ponding operations or both when it determines that emergency conditions exist such as equipment failure at the hydropower facilities, ship incidents such as groundings, electrical system difficulties, extreme meteorological conditions, or other circumstances. Apart from the foregoing peaking and ponding operations and emergencies where immediate action is necessary, the IJC’s advance approval shall be obtained through the Board for any other deviations from the flow determined by Regulation Plan 1977-A.

The IJC has received applications from Great Lakes Power Limited and from the Edison Sault Electric Company to conduct further peaking and ponding operations. The IJC has decided to defer consideration of those applications at this time as it has proposed providing authority to the power entities to conduct peaking and ponding operations under the supervision of the Board for an additional year.

The IJC will make a decision on this matter prior to March 20, 2002, when the current authority for peaking and ponding operations expires. Public comment is invited and should be provided to one of the IJC Secretaries by 12:00 noon on Thursday, March 14, 2002:

Gerald Galloway 
Secretary, U.S. Section 
International Joint Commission 
1250 23rd Street NW, Suite 100 
Washington, DC 20440 
Fax: (202) 467-0746 Murray Clamen 
Secretary, Canadian Section 
International Joint Commission 
234 Laurier Avenue West, 22nd Floor 
Ottawa, ON K1P 6K6 
Fax (613) 993-5583

The International Joint Commission is an international organization established by the Boundary Waters Treaty of 1909 to prevent and resolve disputes over the use of waters shared by the United States and Canada. For more information on the IJC, please visit us at www.ijc.org .


Frank Bevacqua Washington, D.C. (202) 736-9024 Fabien Lengellé Ottawa, Ontario (613) 995-0088