The Great Lakes Pollution: A Historical Overview

The Great Lakes, one of the world's largest surface freshwater ecosystems, have been facing poorer water quality, habitat degradation, and biodiversity loss due to decades of pollution. The primary sources of this pollution are industrial waste, sewage, agricultural runoff, and plastic waste. The lack of government oversight and the closed system of the lakes have allowed pollutants to accumulate, impacting the ecosystem and entering the food chain. While efforts such as shoreline cleanups and legislation targeting plastic production have been made, concrete policy implementations and regulations are needed to address the magnitude of the pollution problem in the Great Lakes effectively.

Industrial waste and sewage

The Great Lakes, one of the world's largest surface freshwater ecosystems, have been subjected to significant pollution from industrial waste and sewage over the years. This has resulted in degraded water quality, habitat degradation, and biodiversity loss. Here is an overview of the situation:

Industrial Waste

The Industrial Revolution and subsequent economic developments have had a profound impact on the water quality of the Great Lakes. Industrial activities have released a range of pollutants into the lakes, including chemicals, acids, oils, and heavy metals. These pollutants have contaminated the water, sediment, and surrounding ecosystems. Even abandoned industrial sites continue to contribute to pollution, as contaminants can be disturbed and released into the water bodies.

Atmospheric deposition is also a significant pathway for industrial pollutants to enter the lakes. Volatile chemicals released from industrial sites can be transported over long distances and deposited onto the lake surfaces through wet or dry deposition. This has been identified as a leading cause of PCB compounds entering the lakes.

Sewage

Untreated sewage has been a major contributor to the pollution of the Great Lakes. In the past, raw sewage was commonly dumped into the lakes, leading to public health issues such as typhoid fever outbreaks. While direct dumping of untreated sewage has decreased, modern challenges remain. Sewage overflows during storms continue to be a problem, impacting water quality and contributing to the proliferation of algae.

Large cities are significant contributors to untreated sewage, and even with improved wastewater treatment facilities, the volume of sewage can overwhelm the systems. Additionally, failing septic systems on farms, vacation homes, and rural dwellings surrounding the lakes contribute to the issue.

Combined Impacts

The combination of industrial waste and sewage pollution has had severe ecological consequences. Excess nutrients, particularly phosphorus, from sewage treatment plants and industrial sources, have led to eutrophication in lakes like Lake Erie. This results in excessive algal growth, reducing oxygen levels and leading to fish kills. The influx of pollutants has also changed the water composition, impacting aquatic life and rendering swimming areas unusable.

Efforts to Address Pollution

Recognizing the severity of the pollution, various efforts have been made to address the issues. The International Joint Commission (IJC) has been active since 1909, monitoring pollution and making recommendations. The 1972 Great Lakes Water Quality Agreement between Canada and the United States provided a framework for joint efforts to improve water quality. Additionally, local communities have implemented measures, such as building sewage plants and installing water filters in industries, to mitigate the damage and slow down the deterioration of the Great Lakes.

Agricultural runoff

Agriculture has played an important role in the history of the Great Lakes region and will continue to do so in the future. However, agricultural practices have also contributed significantly to the pollution of the Great Lakes, particularly Lake Erie.

Farms are the main source of nutrient pollution in the Great Lakes. When it rains, excess fertilizer, manure, and chemicals from farm fields flow into nearby waterways, which eventually reach the Great Lakes. This runoff contains high levels of nutrients like nitrogen and phosphorus, which are vital for plant growth. However, too much of these nutrients in the water can fuel harmful algal blooms and create "dead zones." Algal blooms can make water toxic to fish, wildlife, and even people, as they deplete oxygen levels in the water. In 2014, nearly half a million people lost access to safe tap water for several days due to toxic algae contamination in western Lake Erie.

Additionally, pesticides and waste from agricultural runoff have contributed to the pollution of Lake Erie. The Great Lakes Basin lacked substantial government oversight for a long time, allowing waste and pesticides from farms to make their way into the lake. This has had severe ecological consequences, with dead fish appearing along the lake's shoreline in the 1960s, leading to the phrase "Lake Erie is dead."

The proliferation of algae, such as Cladophora, due to pollution, has created a toxic environment for fish. The algae absorb microplastic fibers, which are ingested by the fish, contaminating the food chain. This pollution has also impacted recreational activities, such as swimming, and businesses dependent on a healthy lake ecosystem, such as fishing shops and boat rentals.

To address agricultural pollution, the Alliance for the Great Lakes is advocating for mandatory regulations to reduce nutrient pollution flowing into the Great Lakes. They are partnering with community groups, researchers, and government agencies to develop cost-effective and equitable solutions to prevent runoff pollution.

Plastic pollution

The Great Lakes, which span over 500 miles from Milwaukee to Buffalo, are the largest surface freshwater ecosystem in the world. They contain 84% of North America's surface freshwater and are home to over 3,500 species of plants and animals. However, they are currently experiencing deteriorating water quality, habitat degradation, and biodiversity loss due to decades of urban, agricultural, plastic, and industrial pollution.

Beach cleanups, such as the Alliance's Adopt-a-Beach program, are one way to help keep plastic out of the Great Lakes. However, they are not enough to solve the magnitude of the problem. Reducing the production of single-use plastic and holding producers accountable across the entire life cycle of their products and packaging are crucial steps in tackling plastic pollution. Increasing recycling rates and passing policies to ban or reduce the use of certain single-use plastic items can also help mitigate the issue.

The effects of plastic pollution on the Great Lakes ecosystem are concerning, with potential impacts on the communities that rely on the lakes for food, water, and income. It is essential to address this issue through individual action, policy implementation, and regulation to protect and preserve the Great Lakes for future generations.

Climate change

Since 1951, annual average air temperatures in the Great Lakes region have increased by 2.3°F (1.3°C). By 2050, average air temperatures are projected to increase by 3°F to 6°F (1.7°C to 3.3°C), and by 2100, they may rise by 6°F to 11°F (3.3°C to 6.1°C). Summer lake surface temperatures are rising faster than the surrounding air temperatures, with Lake Superior's summer water temperature increasing by 4.5ºF between 1979 and 2006. Warmer surface water temperatures in the Great Lakes contribute to lower water levels by increasing evaporation rates and delaying ice formation.

The Great Lakes region is attracting new residents due to its perceived climate safety. However, the impact of human migration on receiving communities is still being studied. To address climate change, there is a focus on transitioning to renewable energy sources, such as solar and wind power, and reducing emissions from coal-fired electricity plants.

Chemical pollutants

The Great Lakes Basin, comprising Lakes Superior, Huron, Erie, Ontario, and Michigan, is one of the world's largest surface freshwater ecosystems, accounting for about 84% of North America's surface freshwater. Over the past two centuries, the Industrial Revolution and western settlement have severely impacted the water quality of the Great Lakes, with chemical pollutants from industrial and agricultural sources being a significant contributor.

Chemical pollution in the Great Lakes has historically come from various sources. Factories along the shores of the lakes, particularly those in Detroit, have dumped acids, iron, oil wastes, and other chemical wastes into the rivers flowing into the lakes. These chemicals, including toxic substances like ammonia and cyanide, have had detrimental effects on aquatic life and the wider ecosystem. For example, cyanide can kill thousands of fish, and ammonia is toxic to many aquatic organisms.

Agricultural runoff has also played a significant role in chemical pollution. Farms in the watershed areas of the lakes have contributed pesticides, fertilizers, and other chemicals that have made their way into the water bodies. This has led to an overabundance of nutrients in the lakes, causing excessive algae growth, a process called eutrophication. The algae disrupt the ecosystem by robbing the water of oxygen, leading to a decline in fish species that rely on oxygen-rich environments.

In addition to these direct sources of chemical pollution, the Great Lakes have also been affected by atmospheric deposition of chemicals. Smokestacks and industrial emissions have released pollutants into the air, which then settle into the lakes through rainfall or dust. This type of pollution is more challenging to control as it can originate from distant sources and be transported over long distances before settling in the lakes.

While efforts have been made to mitigate the impact of chemical pollution, such as the installation of sewage plants and water filters, the persistence of certain chemicals in the environment poses a long-term threat. Pollutants like phosphorus and PCB (polychlorinated biphenyls) can accumulate in fatty tissues of organisms and increase in concentration as they move up the food chain. These toxins can cause cancer, birth defects, and damage to the nervous and immune systems, even at low concentrations.

Overall, chemical pollution in the Great Lakes has had far-reaching consequences, impacting not only the aquatic life and ecosystems within the lakes but also the surrounding communities and human health. Addressing this issue requires a multifaceted approach, including stricter regulations on industrial waste disposal, improved agricultural practices, and continued efforts to reduce the presence of toxic chemicals in the lakes and the surrounding environment.

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