lake shoreline with water an algae green color
The shallow waters of Lake Erie become contaminated with toxin-producing bacteria during a harmful algal bloom, giving it a green tinge. (Michigan Sea Grant Photo/Tom Archer)

Lake levels continue to be above average and reaching near-record highs across the Great Lakes basin, causing problems with coastal erosion, flooding, infrastructure damage and economic loss. In addition to increasing lake levels and more nutrient runoff from stronger storms, the region is also experiencing warming weather and therefore warmer waters. Research points to climate change as the cause. Gabriel Filippelli, professor and director of the Center for Urban Health in the Department of Earth Sciences at Indiana University–Purdue University Indianapolis, references the March 2020 Quarterly Climate Impacts and Outlook Report for the Great Lakes Region—produced by Illinois-Indiana Sea Grant, Midwestern Regional Climate Center and partners—in a climate change story as part of the Pulitzer Center’s nationwide Connected Coastlines reporting initiative. Read the full story: Climate change threatens drinking water quality across the Great Lakes. Excerpt below. 

“Do Not Drink/Do Not Boil” is not what anyone wants to hear about their city’s tap water. But the combined effects of climate change and degraded water quality could make such warnings more frequent across the Great Lakes region.

A preview occurred on July 31, 2014, when a nasty green slime – properly known as a harmful algal bloom, or HAB – developed in the western basin of Lake Erie. Before long it had overwhelmed the Toledo Water Intake Crib, which provides drinking water to nearly 500,000 people in and around the city.

Tests revealed that the algae was producing microcystin, a sometimes deadly liver toxin and suspected carcinogen. Unlike some other toxins, microcystin can’t be rendered harmless by boiling. So the city issued a “Do Not Drink/Do Not Boil” order that set off a three-day crisis.

Local stores soon ran out of bottled water. Ohio’s governor declared a state of emergency, and the National Guard was called in to provide safe drinking water until the system could be flushed and treatment facilities brought back on line.

The culprit was a combination of high nutrient pollution – nitrogen and phosphorus, which stimulate the growth of algae – from sewage, agriculture and suburban runoff, and high water temperatures linked to climate change. This event showed that even in regions with resources as vast as the Great Lakes, water supplies are vulnerable to these kinds of man-made threats.


Illinois-Indiana Sea Grant is a part of University of Illinois Extension and Purdue Extension.

 

 

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Ready for a party? Join us on the newly-expanded Wild Mile for a celebration of our urban waterways and thriving park spaces. Enjoy local beer, food trucks, and an outdoorsy prize drawing while learning about local environmental nonprofits and volunteer opportunities! This event is free and fun for all ages!The block party is rain-or-shine, and we'll only cancel in the case of hazardous weather!This year’s community partners include @Openlands, Current Water, @chicago_enviro, @cleanupclub_chicago, @chicago_birder, Blazing Star School, @cubillinois, Friends of the Bloomingdale Trail, @chicagoshapers, @reducewastechicago, Southern Utah Wilderness Alliance, and @honeycombproject!Learn more at the link in bio.
📢 Show Your Support for Sea Grant! 📢Continued federal funding for Sea Grant in FY26 is crucial, and we need your help to demonstrate the nationwide support for these essential programs.🖊️ Sign the letter urging Congress to continue funding Illinois-Indiana Sea Grant and all 34 state Sea Grant programs:🔗 https://forms.gle/7sPGHGyh8j8a7vfGA or link in bio
Exciting news! The call for sessions for the 2026 Emerging Contaminants in the Environment Conference has been extended! We are excited to offer the opportunity to propose a speaker or panel session during the 2026 Emerging Contaminants in the Environment Conference April 28-29.  The conference will feature traditional 15-minute presentations and a poster session on the latest in emerging contaminant research, policies, and outreach in the soil, water, and air.The deadline to propose a session is September 30, 2025.Learn more at go.illinois.edu/ecec or the link in bio
Stay safe and have fun this Fourth of July with these 5 water safety tips! Click the link in bio to learn more ways to keep yourself and others safe as you enjoy the Lake Michigan beaches this holiday.
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