Lake Superior levels rise (but just a smidgeon)
By SooToday.com Staff
June 1, 2007
Update on Lake Superior outflow
The International Lake Superior Board of Control, under authority granted to it by the International Joint Commission, has set the Lake Superior outflow to 1,530 cubic metres per second (m3/s) (54.0 thousand cubic feet per second (tcfs)) for the month of June.
This is the outflow recommended by the regulation plan for the month of June and is an increase from the May outflow, which was 1,500 m3/s (53.0 tcfs).
The June outflow will be released by discharging about 1,418 m3/s (50.0 tcfs) 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 will be maintained at the existing setting equivalent to one-half gate open (four gates open 20 cm, or about 8 inches each).
There will be no change to the setting of Gate #1 that supplies the Fishery Remedial Works.
This past month the water supplies to the Lake Superior and Lakes Michigan-Huron basins were well below their long-term averages for May.
The level of Lake Superior remains below its chart datum level.
The levels of Lake Superior and Lakes Michigan-Huron are expected to rise in June.
Currently, the Lake Superior level is about 53 cm (21 inches) below its long-term average beginning-of-June level, and is 40 cm (16 inches) below the level recorded a year ago.
This past month the level of Lake Superior rose 3 cm (1 inch), while on average it rises by 10 cm (4 inches) in May.
The last time Lake Superior was lower at this time of year was in 1926.
The level of Lakes Michigan-Huron rose 2 cm (1 inch) this May, while on average the level of these lakes rise by about 8 cm (3 inches) in May.
The level of Lakes Michigan-Huron is now about 47 cm (18 inches) below its long-term average beginning-of-June level but is 8 cm (3 inches) lower than it was a year ago.
The Board continues to monitor conditions both on Lake Superior and downstream and will advise the International Joint Commission accordingly on those conditions.
Brigadier General Bruce A. Berwick, commander, Great Lakes and Ohio River Division, U.S. Army Corps of Engineers, is the United States board member.
Mr. David Fay is the board member for Canada.