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The Kingston Whig-Standard had this in todays newspaper - something we all know about.
David aka Superdad
If it seems that Kingston’s receding shoreline is more pronounced this fall, you’re not imagining anything: Lake Ontario’s water level is not only a foot lower this year than last, it’s at its lowest point in the past 48 years.
According to statistics compiled by the International St. Lawrence River Board of Control, Lake Ontario measures 243.3 feet deep, seven inches lower than it was last month and 11 inches below its October average.
But it doesn’t approach the lowest recorded level for October, however. That belongs to 1934, when the lake’s water level was down another 20 inches.
Rob Caldwell, a representative of the International St. Lawrence River Board of Control that controls the outflows of Lake Ontario, said that being 30 centimetres below average has happened about a dozen or so times before 1964.
A lack of precipitation this year hasn’t helped, and “it has been exacerbated by the dry, hot summer,” he said.
The water level of each of the Great Lakes is lower than normal, statistics show.
John Casselman, an adjunct professor in Queen’s University’s biology department, participated in compiling International Joint Commission studies on the water levels, and remembers the last time the water level dipped so decisively.
“In 1964, it was rather interesting because commercial fishermen came to me and said, ‘You have to see this,’ ” he recalled.
“This is in December … and the water levels continued to stay low and go down, and they noticed through the ice a lot of dead fish on the bottom.”
Those dead fish — ones such as pike and perch that spawn in shallow water — fell victim to what’s known as “winter kill.”
“When the ice comes in, then the oxygen is fixed in the water column,” Casselman explained.
“If the areas are shallow where these small fish are, the oxygen is quickly depleted by the bottom mud.”
The damage the low water level may cause to assorted aquatic life may not be seen for some time, he said, and the spring will also determine the fate of some spawning species.
“That was very devastating because it essentially killed the ’64 year class of fish that would be recruited,” Casselman said.
“Even more devastating, the water stayed down and the next spring those fish didn’t spawn successfully. So we had a real hiccup in recruitment.
“The anglers don’t see that, of course, until they try to catch the fish four or five years later.”
If the water level is still low come spring, it may force some species to spawn elsewhere, and that could lead to what Casselman calls “hybridizing” of species.
“We saw hybrids produced that year, which was quite interesting,” he said, noting that northern pike spawned with muskellunge and also grass pickerel, which is also a member of the pike family.
The low lake level also has an impact on other aquatic organisms that spend winters nestled in silt such as the American eel, which is currently an endangered species in Ontario and the subject of a paper Casselman is currently writing.
Casselman feels that part of the blame for the low water levels of Lake Ontario and the St. Lawrence River lies with global warming.
For every degree the temperature rises, the evaporation rate rises by 6%. Evaporation, and the resulting drought, is much more noticeable to the average person than the temperature being a degree warmer, he feels.
Lee Willbanks, executive director of the Clayton, N.Y.-based conservation group “Save the River,” said that he’s been told by the group’s consulting scientists and researchers that the low water level is a cyclical occurrence.
“We’ve known since February or March that we were entering what turned out to be just a dramatically dry year pretty much across great pieces of both our countries,” he said.
“Since Ontario is a receiver of the other Great Lakes, and our focus is the St. Lawrence River, you could see weekly that the sources were just not delivering the supply of water that you would normally get, didn’t realize it would go on as long as it has or be as dramatic as it’s been. It’s part of the cycle.”
Willbanks and company, who also hold the title of Upper St. Lawrence Riverkeeper, see the lake’s low water level as a natural occurrence.
“We actually think periods of low water are good for the whole system,” he said.
“It’s going to help, we hope, clear out these monoculture cattail wetlands and return them to a more natural, open, and supportive of a whole bunch of species kind of situation.”
Any drop in the number of fish will rebound, Willbanks has been told.
“Their spawning beds, which are in shallow water, are being choked by cattails and that’s why a year or two — in a cycle that runs 20, 30 years — you might have one non-productive breeding season, but, because they live and breed in multiple years, the idea is if you clear out their historic spawning beds and make it that they can access those, in the long run you’ll see the numbers come back,” he offered.
This year in the cycle is something species rely upon, Willbanks said, and is a part of the “big picture.”
“Everybody hates it because it shortens the boating season, it’s not as much fun if you’re a small, recreational boater and you’re finding new places where the shoals are coming up that we haven’t had them before,” he said. “Year over year over year, the cycle works to everybody’s advantage if we return to a more natural ecology.”
The low water level can also have a subtler impact, said Jeff Ridal, executive director of the St. Lawrence River Institute of Environmental Studies in nearby Cornwall.
“We know when we have low water levels we expose more of the near-shore areas, and, particularly when they drop quickly, what happens is any algae coating the surface of those rocks then is exposed to the atmosphere, dies off and then again you could have a water-quality impact,” he said. “But that’s more of a summer issue.”
That could result in water having “undesirable tastes and odours,” he said.
John Casselman believes the weather in the coming weeks is key to what the spring will hold for some species.
“What’s really important here is the fall rains,” he said.
“If we don’t get the fall rains, then we won’t see recharge or the water level either stabilized or become higher. It will continue to drop.”
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