This story comes from the Wisconsin News Collaborative, a partnership between WPR, WUWM, and WXPR.
U.S. and Canadian experts are urging government agencies to take swift action to address the threats posed by more frequent harmful algal blooms on Lake Superior.
The nonprofit, nonpartisan Burke Center for Ecosystem Research released a white paper on the call to action this week. The paper outlines eight recommendations from over two dozen researchers and resource managers from the two nations who convened at a June water summit in Duluth.
Among the recommendations, experts are urging more funding for research into what’s driving potentially toxic blue-green algae blooms and a real-time monitoring network of buoys to detect and analyze blooms that have emerged since 2012.
A panel of experts discussed the growing problem Tuesday at the University of Wisconsin-Superior, including Cherie Hagen, Lake Superior Program Manager with the Wisconsin Department of Natural Resources.
“We’re seeing these blooms on an annual basis, they’re not one-offs. We’ve been doing monitoring. We’re getting more information, but we still don’t completely understand. More investment is needed for us to take it to the next level, so we really can take action once we have a better understanding of the drivers,” Hagen told WPR.
Blue-green algae blooms often look like pea soup or green and blue paint, and they sometimes contain toxins that can make pets and people sick. They tend to occur in warmer waters with more nutrients, such as Lake Erie. But Lake Superior’s reputation as cold and pristine has often made it difficult to attract funding for protection and restoration, according to the paper.
More action is needed now as climate change drives more extreme weather in the Great Lakes region, said Emily Finnell, Great Lakes Senior Advisor and Strategist for the Michigan Office of the Great Lakes. She noted Lake Superior is one of the fastest warming lakes in the world.
“When we think of Lake Superior, we think about protection,” Finnell said. “Now, our mindset really needs to shift to how do we better understand these environmental impacts that are happening in the lake that are causing these blooms.”
The report recommends increased attention and investment under the Great Lakes Water Quality Agreement and Great Lakes Restoration Initiative. Under the agreement, the U.S. and Canada have committed to protecting and restoring the Great Lakes, laying out key priorities for each lake in their management plans. Work has accelerated with the help of GLRI funding.
The Great Lakes cleanup program has devoted nearly $4.8 billion to thousands of projects since 2010, including around $1 billion in Wisconsin.
Much remains unknown about Lake Superior blooms
The first blue-green algae bloom on Lake Superior was detected in 2012 following storms that caused massive flooding in the region. Another large bloom formed in 2018 that stretched more than 50 miles along the lake’s south shore from Duluth-Superior toward Ashland. Those occurred in years that saw warmer waters and storms that are only expected to occur once every 500 to 1,000 years.
Blooms have been detected almost every year since. The Wisconsin DNR has recorded seven blooms in the inner harbor and St. Louis River estuary in Duluth-Superior this year. One included a bloom at Barker’s Island in Superior that resulted in a beach closure, and two more blooms were spotted in Canadian waters at Black Bay and Pukaskwa National Park.
Blooms tend to form and disappear quickly, said Chris Filstrup, an applied limnologist with the Natural Resources Research Institute at the University of Minnesota-Duluth. He said buoys that provide real-time monitoring can fill in gaps.
“Right now, with our reactive approach with sending people out there in a boat to collect a sample, the problem is we don’t know what those conditions are that preceded the bloom,” Filstrup said. “Buoys are able to tell us before, during, and after conditions, so we can really get a good sense of what’s going on with those harmful algal blooms.”
Annual outbreaks of harmful blooms on Lake Erie have extended up to roughly 100 miles between Toledo and Cleveland, Ohio. In 2014, a bloom affected the water supply in Toledo, prompting a do-not-drink order for around half a million residents that lasted almost three days.
The report recommends developing a forecasting system for blooms on Lake Superior similar to bloom forecasting on Lake Erie that’s conducted by the National Oceanic and Atmospheric Administration. The forecasts are developed using data from multiple sources that include water sampling, buoys and satellite imagery, said Chris Winslow, director of Ohio State University’s Stone Lab and Ohio Sea Grant College Program.
“We can actually detect cyanobacteria, blue-green algae…from a satellite because we did that background work,” Winslow said. “It’s doable in Lake Superior.”
The report also recommends collaborating with tribes on research into the effects of blooms on culturally significant species, as well as assessing the impacts on local communities and economies.
Peter Annin, executive director of the Burke Center, said the nonprofit plans to hold events in major cities within the Lake Superior watershed to educate people about the water summit and recommendations for addressing blooms.
“The community of the lake needs to band together and try and figure out what the causes are and what eventually some potential solutions might be,” Annin said.
The Burke Center will offer a presentation on the report at the annual meeting of the Great Lakes Commission in Toronto next month.
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