The latest monthly bulletin about Great Lakes water levels, recently released by the U. S. Army Corps of Engineers, is predicting what many who live, cottage, and work on the lakes will not be happy to hear.
While all the lakes are expected to decline over the winter season, as they typically do, “over the next several months it’s predicted that water levels will remain well above average,” says the report. Levels that are higher than average in April, when the lakes begin to rise again because of precipitation and runoff from spring snowmelt, are an indication that 2020 could be another high-water year.
The USACE’s six-month forecast gives a range of possible outcomes, and since much depends on the amount of precipitation we receive, the lakes may not actually reach or exceed this year’s record levels.
If the trend of more spring and summer rainfall continues, however, as Environment and Climate Change Canada has predicted, higher-than-average water levels will likely occur next year and in the years to come. According to ECCC’s Canada’s Changing Climate Report, annual precipitation in Ontario, for example, increased by 9.7 per cent over the latter half of the 20th century and is projected to continue to increase in the current century.
Meanwhile, some of those cottagers and residents concerned about high Great Lakes water levels have been critical of how the waterways in the system have been managed. The International Joint Commission, which is responsible for the management of the levels and flows of water bodies that straddle the border between Canada and the U.S., enacted a new protocol for the system in 2017.
The new regime, called Plan 2014, replaced one that had been in place for about five decades. A recent report in the IJC newsletter Great Lakes Connection says that water levels “across the Great Lakes are primarily the result of natural, uncontrolled water supplies into the basin” and that under “extreme water supplies, regulation Plan 2014 is nearly identical to the previous Plan 1958-DD.”
This year’s record-breaking conditions in the Great Lakes, though, have prompted the International Lake Ontario–St. Lawrence River Board, which administers Plan 2014, to deviate from the plan: the board reported in late September that it is allowing outflows at the Moses-Saunders Dam, to bring down water levels in the lakes, “at record-high rates for this time of year, eclipsing the outflows released at this same time in any other years dating back to 1900.”