The International Lake Superior Board of Control, under authority granted to it by the International Joint Commission, has set the Lake Superior outflow to 2410 cubic metres per second (m3/s) for the month of January, effective January 5th. The outflow is being set to the normal maximum winter flow prescribed by Lake Superior Regulation Plan 2012, and may at times vary due to weather events and changes in hydrologic and ice conditions.
The January outflow will be released by discharging about 2312 m3/s through the three hydropower plants and passing most of the remaining flow through the control structure at the head of the St. Marys Rapids. The gate setting of the control structure for the month of January will be maintained at the equivalent of one-half gate open (four gates open 20 centimetres (cm) each). The one-half gate equivalent setting is the normal winter maximum, and is typically maintained from December through April. There will be no change to the setting of Gate #1, which supplies a flow of about 15 m3/s to the channel north of the Fishery Remedial Dike.
Based on provisional data, water supplies to both Lake Superior and Lake Michigan-Huron last month were higher than any December on record (1900-2014). This was due to above-normal precipitation combined with unseasonably warm temperatures, which resulted in above-normal runoff and below-normal lake evaporation.
As a result, the level of Lake Superior rose 1 cm last month, while on average the lake falls 8 cm in December. The Lake Superior level at the beginning-of-January is 22 cm above average, 2 cm below the level recorded a year ago at this time, and 38 cm above its chart datum level.
The level of Lake Michigan-Huron rose 8 cm last month, while on average the lake falls 4 cm in December. The level of Lake Michigan-Huron is 30 cm above its long-term average beginning-of-January level, 6 cm higher than it was a year ago, and 60 cm above its chart datum level.
The levels of Lake Superior and Lake Michigan-Huron are both expected to resume their seasonal declines in January.
Mr. Jaymie Gadal is the Board Member for Canada. Brigadier General Richard Kaiser is the U.S. Board Member.
For further information, please contact Mr. Jacob Bruxer, Canadian Regulation Representative, International Lake Superior Board of Control, by phone at (613) 938-5862 or by e-mail at [email protected]
Additional information can also be found at the Board’s homepage: http://ijc.org/en_/ilsbc
Or on Facebook at: https://www.facebook.com/InternationalLakeSuperiorBoardOfControl