Great Lakes Water Pollution: A Historical Perspective

The Great Lakes, comprising Lakes Huron, Ontario, Michigan, Erie, and Superior, are the largest source of fresh water on Earth. They span 750 miles from West to East, covering borders in the US and Canada. The lakes have been a source of fishing, boating, and other recreational activities, as well as an important mode of transportation for goods. However, the Great Lakes have faced water pollution issues for over a century due to industrial waste, chemical pollutants, sewage, and agricultural runoff. Lake Erie, in particular, was predominantly polluted by the 1960s due to heavy industrialization along its shores, leading to concerns about its water quality. Today, the lakes continue to face challenges from pollution and climate change, with communities working to address these issues through creative solutions and green economy initiatives.

The Great Lakes are the largest source of freshwater on Earth

The Great Lakes—Lake Huron, Ontario, Michigan, Erie, and Superior—span 750 miles from west to east and are situated across nine state/territory borders: Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio, Pennsylvania, New York, and Ontario. With its bordering territories, Lake Erie collects wastes and chemicals of all kinds from modern civilization, including industrial waste and domestic sewage. The Great Lakes hold over 5,400 cubic miles of water, accounting for more than 20% of the world's surface freshwater. To put that into perspective, the Great Lakes contain enough water to cover the entire lower 48 states to a depth of almost 10 feet.

The Great Lakes are a crucial source of potable drinking water for the US and Canada, with nearly 40 million people depending on them. They are also an important mode of transportation for goods, a hub for recreation, and a source of wildlife and ecosystems. However, the lakes have not always been able to safely provide this diverse quantity of uses. The water quality of the Great Lakes has been dramatically changed over the past two centuries due to western settlement and the Industrial Revolution. The lakes have seen new and unwanted species and pollution from industry, agriculture, and cities.

Many governmental actions and commissions have aided in the cleanup and maintenance of the lakes, and continue to do so today. The 1972 Great Lakes Water Quality Agreement, for example, provided a path forward for Canada and the United States to jointly address these issues. Since its inception in 1909, the International Joint Commission (IJC) has also been involved in Great Lakes water quality issues. The IJC's first Great Lakes water quality assessment started in 1913 and published its final report in 1918. The report found contaminated water around Great Lakes cities and towns, particularly where ships were frequently located.

Today, the Great Lakes' water is still under threat from chemical pollution, with new pollutants including pharmaceuticals and plastic waste. However, efforts to clean up the lakes have been a mix of achievements and challenges.

Industrial and municipal waste

The Great Lakes, which cover nearly 95,000 square miles and hold over 20% of Earth's surface freshwater, have been degraded by industrial and municipal waste for over a century. The lakes and their connecting channels, rivers, and smaller lakes have been used for waste disposal, with industries dumping chemical pollutants and cities discharging sewage and industrial waste.

In the decades leading up to the 1970s, Lake Erie, in particular, was heavily polluted, largely due to the heavy industrial presence along its shores. Factories dumped chemical pollutants into the lake and the waterways that flowed into it, such as the Cuyahoga River and the Detroit River. The Detroit River, which serves as a habitat for many species of aquatic wildlife, was declared in a 1964 report by the International Joint Commission (IJC) to be "polluted bacteriologically, chemically, physically, and biologically so as to interfere with municipal water supplies, recreation, fish and wildlife propagation and navigation." The report also estimated that the lower Detroit River area would see thousands of deaths annually from ducks, geese, and other wildlife species due to oil spills. By the 1960s, Lake Erie had become known as "an odorous, slime-covered graveyard," and dead fish began to appear along its shoreline.

The other Great Lakes have also faced similar issues. Lake Michigan, for example, had problems with chemical contamination in aquatic life in the southern and middle regions, while Lake Ontario suffered from nutrient pollution along its nearshore. The IJC's 1972 Great Lakes Water Quality Agreement provided a path forward for Canada and the United States to jointly address these issues, and progress has been made in the years since. However, toxic pollution in the Great Lakes remains a significant problem, with new types of pollutants, such as microplastics and pharmaceuticals, threatening the ecosystem.

To mitigate the damage and improve water quality, municipalities have upgraded and built water treatment plants, and industrial sites have constructed their own treatment systems. The Great Lakes Water Quality Agreement was updated in 1978 to cover all five lakes and focus on chemicals and toxic substances, and again in 1987 to designate Areas of Concern (AOCs) with dangerous pollutants. The Great Lakes Legacy Act has led to the cleanup of 4.3 million cubic yards of sediment, with $362 million in federal funds spent on cleanup efforts.

The 1972 Great Lakes Water Quality Agreement

The Great Lakes Water Quality Agreement (GLWQA) is a commitment between the United States and Canada to restore and protect the waters of the Great Lakes. The first GLWQA was signed in 1972 by President Richard Nixon of the United States and Prime Minister Pierre Trudeau of Canada. This agreement was a response to public demands for environmental reforms, specifically addressing the issue of excessive algae in Lake Erie caused by high levels of phosphorus.

The 1972 GLWQA only applied to the two lowest Great Lakes, Erie and Ontario, and the international section of the St. Lawrence River. It committed both nations to develop common water quality objectives and regulatory standards for several pollutants, with a focus on point source pollution from phosphorus and nitrogen. To achieve these goals, the agreement encouraged each country to create and implement their own national programs. While the agreement had no formal enforcement mechanisms, it relied on the recognition that binational collaboration was necessary to protect and clean up the Great Lakes.

The 1972 agreement led to some early successes, such as the reduction of total phosphorus concentrations in Lake Erie, which resulted in a quick improvement in water quality. However, not all phosphorus loading targets were met, and the agreement did not cover nonpoint sources of pollution or hazardous toxics. As a result, in 1978, a new GLWQA was signed, broadening the scope to include all the Great Lakes and targeting the elimination of persistent toxic substances.

The 1972 GLWQA was a significant step forward in addressing water pollution in the Great Lakes region, and it laid the foundation for future agreements and collaborations between the United States and Canada to protect and restore the health of the Great Lakes ecosystem.

The impact of human activities on the Great Lakes ecosystem

The Great Lakes—Lake Huron, Ontario, Michigan, Erie, and Superior—cover nearly 95,000 square miles (250,000 square kilometers) and hold over 20% of the Earth's surface freshwater. This vast freshwater source supports a multibillion-dollar maritime economy and provides drinking water for more than 30 million people in the US and Canada. The lakes also serve as a crucial mode of transportation and offer various recreational activities like fishing and boating.

However, human activities have significantly impacted the delicate Great Lakes ecosystem. By the 1960s, industrialization, urbanization, and agricultural practices had severely polluted the Great Lakes, particularly Lake Erie. Factories dumped chemical pollutants, acids, iron, and oil wastes into rivers flowing into the lake, such as the Cuyahoga River and the Detroit River. Agricultural runoff from nearby farms also contributed to the pollution, with fertilizers and pesticides making their way into the water. The lack of substantial government oversight in the Great Lakes Basin allowed these activities to go unchecked, leading to deteriorating water quality.

The consequences of this pollution were dire. The increased algae disrupted the ecosystem by depleting the water of oxygen, affecting aquatic life and recreational fishing. Several fish species, including pike and whitefish, were severely impacted. The phrase "Lake Erie is dead" started appearing in national publications in the late 1960s, reflecting the lake's dire state.

In response to the worsening situation, Canada and the US implemented various measures to address the pollution. They signed the Great Lakes Water Quality Agreement in 1972, focusing on reducing phosphorus loadings and visible pollution. Both countries invested in new sewage treatment facilities and worked with manufacturers to reduce phosphate loads in detergents. These efforts yielded encouraging early results, and by 1974, The New York Times published positive news about the right to reduce pollution in the Great Lakes.

Despite these efforts, toxic pollution in the Great Lakes remains a significant challenge. Industries continue to introduce new chemicals, and regulations struggle to keep pace. Nonpoint source pollution, such as agricultural runoff, contributes to rising nitrogen levels, leading to large blooms of algae. Additionally, wastewater treatment facilities often become overloaded during heavy precipitation, redirecting untreated waste to water sources. The persistent presence of toxic pollutants, including PCBs, DDT, chlordane, lead, copper, and arsenic, underscores the ongoing struggle to restore and protect the Great Lakes ecosystem.

The Great Lakes face new challenges from pollution to climate change

The Great Lakes—Lake Huron, Ontario, Michigan, Erie, and Superior—are the largest source of fresh water on Earth, with a total coastline of almost 11,000 miles. The lakes span 750 miles from west to east and are situated across nine state/territory borders: Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio, Pennsylvania, New York, and Ontario. The Great Lakes Basin provides potable drinking water for millions of people, supports ecosystems, and enables transportation, recreation, and trade.

However, the Great Lakes face significant challenges from pollution and climate change. Over the past two centuries, the Industrial Revolution and western settlement have degraded water quality, introducing pollution from industry, agriculture, and cities. While efforts have been made to address these issues, such as the 1972 Great Lakes Water Quality Agreement between Canada and the United States, the lakes remain vulnerable.

Industrial waste, sewage, and fuel residue continue to create a toxic environment for fish and wildlife. New pollutants, including pharmaceuticals and plastic waste, are also of concern. For example, chemicals like fire retardants and polybrominated diphenyl ethers (PBDEs) are present in the water, air, sediment, wildlife, and people living near the lakes.

Climate change further exacerbates these issues, with rising temperatures, increased severe rainfall events, and more frequent and intense heat waves impacting the region. These changes contribute to algal blooms in Lake Erie, leading to bacteria-polluted drinking water and potential health risks for residents. The composition of forests in the Great Lakes region is also changing, with many tree species shifting northward and iconic north wood tree species being slowly replaced.

Communities around the Great Lakes are working to address these challenges. Midwestern communities are finding creative solutions to clean up pollution, build resilient infrastructure, and create jobs in the green economy. Organizations like the Environmental Law & Policy Center (ELPC) are also actively involved in protecting the Great Lakes, suing to stop construction of facilities that could pollute the lakes and holding government agencies accountable for violations of the Clean Water Act.

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