The Great Lakes Pollution: Causes And Concerns

The Great Lakes, comprising five interconnected bodies of freshwater, are susceptible to pollution from various sources. Human activities, including urbanization, industrialization, agriculture, and climate change, have significantly impacted the delicate ecosystem of the lakes. Pollution in the Great Lakes can be attributed to a range of factors, including industrial waste, sewage, chemical pollutants, plastic waste, and hazardous air pollutants (HAPs). The presence of toxic contaminants, such as mercury, lead, and microplastics, poses a threat to the health of both the environment and the people who rely on the lakes as a source of drinking water.

Industrial waste and agricultural runoff

For decades, factories dumped chemical pollutants into Lake Erie and the rivers flowing into it, such as the Cuyahoga and Detroit Rivers. The lack of substantial government oversight in the Great Lakes Basin allowed waste, pesticides, fertilizers, and other agricultural runoff to contaminate the lake, endangering aquatic life and the health of nearby residents. This led to the declaration that "Lake Erie is dead" in the 1970s, sparking an international movement to address the pollution crisis.

Industrial waste continues to pose a threat to the Great Lakes, with chemicals like fire retardants and polybrominated diphenyl ethers (PBDEs) persisting in the water, air, sediment, wildlife, and people who live nearby. These toxic chemicals have been linked to various health issues, including thyroid disorders, birth defects, infertility, cancer, and neurobehavioral disorders. Additionally, air pollution from heavy industry, urban development, and roadways contributes to ground-level ozone and particulate matter pollution, which can have detrimental effects on human health and the environment.

Agricultural runoff remains a concern, with pesticides and fertilizers entering the Great Lakes ecosystem and contributing to water contamination. The high population density and extensive farmland in the Lake Erie basin make it especially vulnerable to the impacts of agricultural activities. Efforts to reduce pollution from agriculture, such as implementing better land management practices and reducing the use of harmful chemicals, are crucial to protecting the Great Lakes.

Furthermore, the interconnected nature of the Great Lakes means that pollution from industrial and agricultural sources can spread throughout the entire system. As water flows from Lake Superior to the Atlantic Ocean, it carries with it any contaminants, including runoff, debris, and microplastics, which can have far-reaching ecological consequences. Addressing industrial waste and agricultural runoff is essential to preserving the health and biodiversity of the Great Lakes and the surrounding regions.

Plastic pollution

The Great Lakes, one of the world's largest surface freshwater ecosystems, is facing a significant threat from plastic pollution. Each year, an estimated 22 million pounds of plastic end up in the Great Lakes, impacting the ecosystem and the millions of people who depend on it for drinking water.

Consumer products, such as personal care items containing microbeads, also contribute to plastic pollution in the Great Lakes. While there have been efforts to ban microbeads in certain states, such as Illinois, they still pose a significant problem. Additionally, waste from beachgoers, shipping, and fishing activities adds to the plastic debris in the lakes.

Major population centers, including Chicago, Toronto, Cleveland, and Detroit, are the primary sources of plastic pollution in the Great Lakes. The plastic particles released from these cities end up accumulating on the shores of the lakes, impacting the surrounding ecosystems. For example, Lake Michigan receives approximately 5,000 metric tons of plastic pollution per year, while Lake Erie receives 2,500 metric tons.

To combat plastic pollution in the Great Lakes, a combination of individual action and policy implementation is necessary. Reducing plastic usage and consumption can help lower the risk of microplastics entering the water. At the same time, concrete policies and regulations are required to address the root causes of plastic pollution and protect this vital freshwater ecosystem.

Sewage and sanitation

To address this issue, two possible solutions have been proposed: separating the storm and sewage systems or installing holding tanks to capture the overflow until it can be properly treated. However, despite these efforts, sewage continues to pose a threat to the Great Lakes, as evident in the case of Lake Michigan. The situation is further exacerbated by the presence of nuclear power plants along the lake's shores, which raises concerns about potential radioactive leaks.

The impact of sewage pollution on the Great Lakes ecosystem is significant. It not only makes the water dangerous for human use but also has detrimental effects on aquatic life. For example, sewage can kill fish and contribute to the proliferation of certain types of algae, such as Claudophora, which thrives due to the absence of competing phytoplankton. This disruption in the natural balance can have far-reaching consequences for the entire food chain within the Great Lakes ecosystem.

In addition to sewage, sanitation issues related to industrial waste and agricultural runoff have also played a role in polluting the Great Lakes. For decades, factories have discharged chemical pollutants into the lakes and their tributary waterways. This problem was particularly acute in Lake Erie due to the heavy industrial presence along its shores. Pesticides, fertilizers, and waste from surrounding cities, industrial plants, and agricultural activities have all contributed to the degradation of water quality in the Great Lakes.

To summarize, sewage and sanitation issues, including inadequate treatment facilities and combined sewer systems, continue to pose a significant threat to the Great Lakes. These issues, coupled with industrial and agricultural pollution, have resulted in a complex web of ecological challenges that require concerted efforts to address and mitigate their impact on this vital freshwater resource.

Air pollution

Ground-level ozone is formed when pollutants from cars, trucks, and fossil-fuelled power plants interact with sunlight. The ozone and other pollutants can then be concentrated in localized pockets due to differences in water and air temperatures, onshore and offshore winds, and atmospheric pressure. These conditions make it difficult to track and manage air quality in the region.

The sources of air pollution that affect the Great Lakes include industrial activities, transportation, and agricultural practices. Chemicals like fire retardants and polybrominated diphenyl ethers (PBDEs) are present not only in the water but also in the air, sediment, wildlife, and people living near the Great Lakes. These chemicals are persistent, toxic, and bioaccumulative, leading to various health issues such as thyroid disorders, birth defects, infertility, cancer, and neurobehavioral disorders.

Additionally, the burning of fossil fuels and industrial processes release toxic emissions into the air, contributing to air pollution. These emissions can contain harmful substances such as nitrogen oxides, sulfur dioxide, particulate matter, and volatile organic compounds, which have detrimental effects on both human health and the environment.

To address these issues, scientists and regulators are utilizing satellite data and custom models from NASA to better monitor and understand ozone pollution. This information is crucial for informing local decision-making processes aimed at improving air quality in the Great Lakes region. Efforts to reduce air pollution in the Great Lakes basin are essential to protect the health and well-being of the surrounding communities and to preserve the delicate ecosystem of these vital freshwater bodies.

Oil spills

Today, oil production in the north-central United States and western Canada has been increasing rapidly since 2010, with pipelines and rail transport being the dominant modes of crude oil transportation through or near the Great Lakes basin. This increase in oil production and transportation near the Great Lakes raises concerns about potential oil spills and their ecological impact on the region.

The potential impacts of an oil spill in the Great Lakes depend on various factors, including the density and viscosity of the oil, as well as the location and environmental conditions of the spill. Oil spills can have detrimental effects on the aquatic food chain, from plankton to fish, fish-eating birds, and mammals. The Great Lakes provide the largest source of fresh surface water for almost 40 million people, so oil spills pose a significant risk to drinking water sources, especially when currents transport crude oil towards drinking water intakes.

To address these concerns, the International Joint Commission's Great Lakes Science Advisory Board is working to identify vulnerable areas and determine the observed and potential impacts of crude oil spills. Additionally, government agencies are responsible for spill response and have protocols in place to contain and remove spilled oil. However, challenges remain, especially in ice-covered waters, and for spills of heavier crude oils that sink immediately. Researchers are also preparing for potential oil spills in the Great Lakes by rethinking response strategies and exploring the unique stakes involved in a freshwater spill.

Frequently asked questions