Great Lakes Water Pollution: A Serious Concern?

The Great Lakes, comprising Lakes Huron, Ontario, Michigan, Erie, and Superior, are the largest freshwater system on Earth, providing drinking water to 40-42 million people. They are also a source of tourism, recreation, and industry, with fishing alone supporting a $7 billion economy. However, the Great Lakes have a long history of industrial, agricultural, and urban pollution, causing habitat degradation, biodiversity loss, and contaminated drinking water. Plastic pollution, in particular, is a significant issue, with more than 22 million pounds of plastic entering the lakes annually, breaking down into toxic microplastics that are ingested by wildlife and humans. Climate change further exacerbates these issues, with rising temperatures leading to lowered water levels and an increase in severe storms and rainfall events, causing sewage overflows. While efforts are being made to remediate contaminated sediments and address pollution sources, the Great Lakes remain under serious threat from human activities and the impacts of climate change.

Plastic pollution

A 2016 study by the Rochester Institute of Technology found that nearly 10,000 metric tons (or 22 million pounds) of plastic debris enter the Great Lakes every year from the United States and Canada. Lake Michigan receives the highest amount of plastic pollution, followed by Lake Erie and Lake Ontario. Plastic accounts for approximately 80-85% of the litter on the shorelines of the Great Lakes, with major population centers like Chicago, Toronto, Cleveland, and Detroit releasing more plastic particles than accumulate on their shorelines.

The plastic pollution in the Great Lakes includes dense plastic that quickly sinks and surface plastics like microbeads, fragments, microfibers, pellets, plastic line, and Styrofoam. These plastics can be consumed by wildlife and enter the food chain, potentially impacting human health as well. Microplastics have been found in Great Lakes fish, drinking water, bottled water, and beer. Plastic pollution also affects open-water, shoreline, and benthic environments, and it can have long-term adverse ecological and economic impacts, including the dispersal of persistent organic pollutants.

The sources of plastic pollution in the Great Lakes include microplastic beads from consumer products, pellets from the plastic manufacturing industry, and waste from beach-goers, shipping, fishing activities, and wastewater treatment plants. Communities near plastic manufacturing factories suffer significant harm from the dangerous chemicals and toxic emissions released during production.

Addressing plastic pollution in the Great Lakes will require significant economic investment, likely exceeding $400 million annually. However, there are efforts to combat this issue through legislation, increased data collection, and community initiatives to reduce plastic use and improve reuse systems.

Industrial, agricultural and urban pollution

The Great Lakes, comprising Lakes Huron, Ontario, Michigan, Erie, and Superior, form the largest freshwater system on Earth. They provide drinking water to 40-42 million people and support a vibrant local economy through tourism, recreation, and industry. Fishing alone supports a $7 billion economy, and the lakes form rich ecosystems of fish, birds, and other species.

However, the Great Lakes have faced serious water pollution issues, primarily from industrial, agricultural, and urban sources. Industrial pollution has been a significant contributor to the problem. For decades, factories dumped chemical pollutants, acids, iron, and oil wastes into the lakes and the waterways that flowed into them, such as the Cuyahoga and Detroit Rivers. This lack of government oversight allowed waste, pesticides, and sewage from surrounding cities, industrial plants, and agriculture to contaminate the lakes.

Agricultural pollution has also played a significant role in the degradation of the Great Lakes. Agriculture occupies about one-quarter of the land surrounding the Great Lakes, and chemical fertilizers, manure, and pesticides from farm fields flow into the waterways during rainfall. This runoff contains pathogens, bacteria, and excess nutrients like nitrogen and phosphorus, leading to harmful algal blooms that can contaminate drinking water and create "dead zones" where aquatic life cannot survive.

Urban pollution has further exacerbated the issue. Plastic pollution is a serious concern, with more than 22 million pounds of plastic ending up in the Great Lakes each year. These plastics break down into toxic microplastics that contaminate the water, fish, and drinking sources for millions of people. Communities near plastic manufacturing facilities suffer additional harm from the release of dangerous chemicals and toxic emissions.

The pollution in the Great Lakes has led to initiatives aimed at reducing pollution and restoring the health of the lakes. Organizations like the Alliance for the Great Lakes and the Environmental Law & Policy Center (ELPC) are working to address plastic pollution, advocate for legislation, and hold pollution control agencies accountable. Midwestern communities are also finding creative solutions to clean up old pollution and build resilient infrastructure.

Climate change

Rising temperatures have exacerbated algal blooms in Lake Erie, leading to bacteria-polluted drinking water in Toledo, Ohio, which potentially caused harmful health conditions for half a million residents. Warmer surface water temperatures in the Great Lakes have also contributed to lower water levels by increasing evaporation rates and causing lake ice to form later than usual. This has had a direct impact on shipping, with cargo tonnage reduced by 5 to 8 percent between 1997 and 2000, leading to increased shipping costs. Lower water levels can also affect water supplies, infrastructure, and shoreline ecosystems. While some years have seen high precipitation leading to higher-than-average water levels, scientists predict that overall, there will be larger year-to-year variability, driven by periods of drought and extreme precipitation.

To address these challenges, there is a need to drastically reduce greenhouse gas emissions and help the Great Lakes region retain its natural balance. This includes promoting smart alternative energy production, such as solar and wind energy, in a way that is productive and limits disruption to natural systems. Public-private partnerships are also being formed to accelerate the adoption of renewable energy, support economic growth, and address environmental justice. For example, closing coal-fired electricity plants in Indiana will not only reduce emissions but also improve the health of at-risk residents.

Invasive species

The Great Lakes are the largest freshwater system on Earth, providing drinking water to 42 million people. They are also home to a vibrant local economy, including tourism, recreation, and industry. The lakes are also crucial for wildlife and ecosystems. However, the Great Lakes face many challenges, including the threat of invasive species.

The Great Lakes Restoration Initiative (GLRI) is a program that has been working to protect and restore the Great Lakes since 2010. GLRI agencies and their partners have been working to prevent new introductions of invasive species and to control existing invasive species populations. They set ambitious goals, provide resources and funding, and encourage strong interagency coordination. One of the key challenges is closing the vectors of introduction, including illegal transport, discharge of ballast water through shipping, inadvertent introduction by boats, and release of live bait.

In addition to the work of the GLRI, successful partnerships involving federal, state, provincial, and Tribal agencies, as well as nonprofits, have been key to addressing the challenge of invasive species in the Great Lakes. These partnerships have made important strides in recent decades to detect, prevent, and control invasive species.

Contaminated sediments

Water pollution in the Great Lakes is a serious issue. The Great Lakes—Lake Huron, Ontario, Michigan, Erie, and Superior—form the largest freshwater system on Earth, providing drinking water to 42 million people. They also support a vibrant local economy of tourism, recreation, and industry, with fishing alone supporting a $7 billion economy.

However, the Great Lakes have long faced pollution problems. In 1964, an International Joint Commission report declared that the lower 26 miles of the Detroit River were "polluted bacteriologically, chemically, physically, and biologically so as to interfere with municipal water supplies, recreation, fish and wildlife propagation and navigation." By the 1960s, Lake Erie had become predominantly 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, and agricultural runoff, including fertilizer and pesticides, also contributed to the pollution.

Today, contaminated sediments continue to be a significant problem in the Great Lakes basin. While progress has been made in reducing the discharge of toxic and persistent chemicals, high concentrations of contaminants in the bottom sediments of rivers and harbors remain a concern. These contaminants can be dredged up by storms, ship propellers, and bottom-dwelling organisms, entering the food chain and posing risks to aquatic organisms, wildlife, and humans. Advisories against fish consumption are in place in most locations around the Great Lakes due to the potential presence of heavy concentrations of toxic substances in the tissues of fish.

The Great Lakes Legacy Act and Great Lakes Restoration Initiative funding programs have accelerated the rate of sediment remediation activities, and the EPA provides support to federal, state, and tribal partners to address contaminated sediments. From 1997 to 2007, 5.5 million cubic yards of contaminated sediments were remediated in the U.S. Great Lakes Basin.

Despite these efforts, challenges remain. The Enbridge Line 5, a 60+ year old pipeline, carries over 20 million gallons of unrefined oil every day along the lakebed between Lakes Michigan and Huron, posing a threat to the drinking water of millions. Climate change is also exacerbating issues such as toxic algae and shoreline erosion. Additionally, plastic pollution remains a serious problem, with more than 22 million pounds of plastic ending up in the Great Lakes each year and breaking down into toxic microplastics that contaminate the water and pose risks to public health.

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