CANADA—Based on indicators of ecosystem health, the Great Lakes are collectively assessed as ‘fair and unchanging’ in the State of the Great Lakes 2022 Report. While progress has been made in reducing toxic chemicals and the establishment of new non-native aquatic species, significant concerns remain. Algal blooms, nutrient levels and the impacts of invasive species such as zebra and quagga mussels continue to pose threats to lake health, and climate change is only intensifying some of these threats.
John Hartig, a visiting scholar with the Great Lakes Institute for Environmental Research at the University of Windsor, pointed out it’s been 50 years since Canada and the United States signed the Great Lakes Water Quality Agreement (GLWQA), meant to restore and protect the Great Lakes.
“It’s still heralded throughout the world as pretty unique for two countries working this long together on a resource and cooperating to the extent they do, whether it’s assessing the state of the Great Lakes or remedial action plans for areas of concern or lake-wide management plans, it’s pretty amazing to reflect back on just how bad it was 50 years ago,” Dr. Hartig said. “One of the things that amazes me is that young people don’t know that.”
There were rivers catching on fire on both sides of the border because of oil pollution back then. “You had dead rivers with very little, and in some cases, no life within them,” he said. “What a turnaround.”
There have been some pretty dramatic improvements in general and Lake Huron is in pretty good shape, he added. What’s most hopeful to Dr. Hartig is the return of bald eagles, reproducing peregrine falcons, osprey, lake sturgeon, lake whitefish, beaver and river otter (which had been gone since the fur trade era) where he lives, in the Windsor-Detroit area. “What a message of hope this can give everyone,” he said. “Of course, there’s lots to do.”
“Cootes Paradise, in Hamilton, is a model for the whole Great Lakes. Randle Reef in Hamilton Harbour is the largest remediation project in the Great Lakes, and now that’s leading to connecting more people with Hamilton Harbour and economic revitalization.”
One US study showed that for every dollar spent on remediation, you get $3.48 in return on investment. Those are important arguments for us to make, said Dr. Hartig, as well as the fact the lakes are becoming healthier for people, fish and wildlife, with improved aesthetic and quality of life values.
One ecosystem health indicator that remains a concern throughout the Great Lakes is the introduction of new, non-native aquatic species. “My region has been ground zero for zebra mussels and quagga mussels. We can’t do enough to prevent the introduction of these things. Once they’re there, it’s like an uncontrolled experiment,” he said. “They’ve altered the food web of all the Great Lakes and the cost of dealing with them is exorbitant, so we need to place a high priority on keeping them out, on early detection and rapid response.”
One of the things the report brought up for Lake Huron is nutrient depletion in the open, deeper waters. Then there’s the three main areas in the Great Lakes impacted by algal blooms caused by excess nutrients: western Lake Erie, Saginaw Bay on Lake Huron and Green Bay on Lake Michigan.
Overall, levels of PCBs and other toxic chemicals have gone down and have sort of plateaued, he said. There’s also long-range transport of toxic chemicals as well, which can come in from outside the watershed. “We want to do everything humanly possible to live up to the GLWQA agreement’s goals of zero discharge and virtual elimination of persistent toxic substances. The long-term goal is sustainability, so that’s closed loop systems where there’s no waste product. It becomes a product for making something else.”
There are good examples of using an ecosystem approach to clean up areas of concern, like Collingwood harbour and Severn Sound. “They’re off the list,” Dr. Hartig said. “That’s two of the nine and one other one at Spanish is an area of concern in recovery. That means they’ve done all the management actions and now they’re monitoring to see how the ecosystem responds. That’s really good for Lake Huron. We don’t want to get to a point where we have more areas of concern in the future or some of those have to go back on a list. Circular economy, design for environment and full cost accounting, those are the tools to get us there.
The report didn’t mention microplastics but that is an issue. “The concern we all share for microplastics should drive the circular economy as well as the contaminated sediment we need to deal with,” said Dr. Hartig. “Clearly there’s more that needs to be done.”
The report acknowledges climate change as a significant developing threat to the Great Lakes. Climate change is the most pressing environmental challenge of our time, Dr. Hartig said. “Scientists call climate change a threat multiplier. Other threats like harmful algal blooms, or runoff from our agricultural lands, loss of wetlands, so many different things are made worse by the increasing intensity and frequency of climate change. Erosion is getting worse along the shorelines, even on Lake Huron. Once in two-hundred-year floods are becoming more frequent wherever you are. If we have some contaminated sediment hotspots, we need to get after them now while we can still do something.”
Warming temperatures are affecting fish communities, birds and salamanders, said Dr. Hartig. “There’s some really good evidence out there that we’re already seeing the impacts of climate change in the Great Lakes. Another thing to think of is the human population around the Great Lakes. Think of these really warm days with really high humidity. The human health effects are something else we should pay attention to.”
The whole environmental movement came about in the 1960s and early 1970s because people spoke out, with a massive outcry from people for a cleaner environment. It was the start of Earth Day. It was when the Canada Water Act of 1970 was introduced, and the Great Lakes Water Quality Agreement of 1972, as well as the U.S. Clean Water Act and the Endangered Species Act of 1973. “What a set of accomplishments because people spoke out,” Dr. Hartig said. “I think one of the major accomplishments of today is all of these smaller, grassroots organizations working on protecting the place they call home.”
Grassroots support and a groundswell of NGOs and First Nations speaking out is needed now to further restore and protect the Great Lakes, he added. “Citizen outreach, citizen engagement, advocacy will be key. We need a strong voice that this is important, not only for our generation but for future generations.”