The Great Lakes Pollution: Causes And Concerns

The Great Lakes, comprising Lakes Huron, Ontario, Michigan, Erie, and Superior, are the largest source of freshwater on Earth. However, the lakes have historically struggled with pollution, with Lake Erie being declared dead in 1970. Pollution in the Great Lakes can take many forms, including pesticides, herbicides, sewage, and litter, with plastic accounting for about 80% of the litter on Great Lakes shorelines. The presence of microplastics in the lakes has also been detected in the guts of fish, raising concerns about the potential health risks. Other sources of pollution include industrial waste, agricultural runoff, and municipal sources, with chemicals such as fire retardants, polybrominated diphenyl ethers (PBDEs), DDT, PCBs, and mercury persisting in the water and accumulating in aquatic organisms. These pollutants can have detrimental effects on water quality, wildlife diversity, and human health, leading to issues such as harmful algal blooms and eutrophication. While efforts have been made to address pollution in the Great Lakes, it remains a complex issue that requires systemic solutions and collaboration between various stakeholders.

Plastic pollution

The Great Lakes, which span over 500 miles from west to east, are a system of five interconnected freshwater lakes: Lake Superior, Lake Michigan, Lake Huron, Lake Erie, and Lake Ontario. They provide drinking water for 40 million people and support recreation, fishing, and wildlife habitats. However, they are facing a significant threat from plastic pollution.

Microplastics, plastic particles smaller than 5 millimeters, have been found in high concentrations in the Great Lakes. They are ingested by wildlife, such as fish, mussels, algae, invertebrates, and birds, potentially impacting their health and nutrition. Microplastics have also been detected in drinking water, bottled water, and even beer, raising concerns about their potential effects on human health. While the impact of microplastic ingestion on humans is still being studied, some research suggests it could affect brain development during pregnancy and reproductive systems.

To combat plastic pollution in the Great Lakes, various efforts are being made. Volunteers with the Alliance's Adopt-a-Beach program have been working tirelessly to remove trash from the shorelines, collecting tens of thousands of pounds of litter, most of which is plastic. Additionally, organizations like Environment Illinois and the Alliance for the Great Lakes are advocating for policy changes to reduce single-use plastic and hold producers accountable for their products' entire life cycles. There is also a focus on increasing access to water refill stations and improving reuse systems to reduce the reliance on single-use plastic items.

While beach cleanups and individual efforts are important, a more systemic approach is needed to address the magnitude of the plastic problem in the Great Lakes. Reducing the production of single-use plastic and implementing concrete policies and regulations are crucial steps in protecting this vital freshwater ecosystem and the communities that depend on it.

Chemical pollution

The Great Lakes, once an abundant source of natural beauty and resources, have faced significant chemical pollution over the years, threatening their delicate ecosystems and the health of surrounding communities. Chemical pollution in the Great Lakes has been caused by a combination of industrial, agricultural, and urban activities, with a history that dates back several decades.

In the past, factories along the shores of the Great Lakes, particularly Lake Erie, dumped chemical pollutants directly into the lakes and connected waterways. This lack of regard for the environment, coupled with insufficient government oversight, allowed waste, pesticides, fertilizers, and other industrial chemicals to contaminate the water. The issue was so severe that, by the 1960s, Lake Erie was declared "dead," with dead fish appearing along its shoreline and oil spills causing wildlife deaths.

One of the significant contributors to chemical pollution in the Great Lakes is the presence of persistent and toxic chemicals, such as polychlorinated biphenyls (PCBs), DDT, mercury, and more recently, polybrominated diphenyl ethers (PBDEs). These chemicals are known for their resistance to degradation and tendency to bioaccumulate in organisms, leading to various health issues. For example, exposure to PBDEs has been linked to thyroid disorders, birth defects, infertility, and cancer. While efforts to ban and reduce the use of PCBs have been successful in decreasing their levels in the lakes, they continue to persist in the environment, especially in the sediments on the lake floors.

Agricultural and urban runoff also play a role in chemical pollution. Nutrient pollution, especially from phosphates in detergents and sewage, contributes to toxic algal blooms, which deplete oxygen levels in the water. Microplastics, resulting from the breakdown of plastic items, are another emerging concern. These tiny plastic particles are consumed by aquatic organisms and can absorb and release chemicals and bacteria, passing them up the food chain and potentially affecting human health. Climate change further complicates cleanup efforts, as warmer water temperatures and increased flooding impact oxygen concentrations and contribute to infrastructure damage.

The complex nature of chemical pollution in the Great Lakes has led to ongoing challenges in remediation. While progress has been made in addressing some historical pollutants, new types of toxic pollution continue to emerge, requiring constant vigilance and innovative solutions. The health and well-being of the Great Lakes ecosystem and the communities that depend on them remain at risk until effective measures are implemented to address these chemical contaminants.

Industrial waste

Legislation has been passed to address industrial waste, and clean-up orders are enforceable in state and federal courts. However, sewage continues to be an issue, as combined storm water and sanitary sewer systems can cause raw sewage to bypass treatment plants during heavy rainstorms. To mitigate this, storm and sewage systems must be separated, or holding tanks are needed to capture the overflow for treatment.

In addition to industrial waste, the Great Lakes face pollution from other sources, including agricultural and urban runoff, which can introduce fertilizers, pesticides, and sewage seepage into the lakes, leading to elevated nitrate and phosphate levels. These pollutants can cause harmful algal blooms and eutrophication, impacting aquatic life and human health.

To preserve the health of the Great Lakes, it is essential to address all sources of pollution, including industrial waste, through a combination of legislation, infrastructure improvements, and public awareness.

Sewage

The pollution of the Great Lakes by sewage can be traced back to the combined stormwater and sanitary sewer systems. During heavy rainstorms, the flow exceeds the capacity of the treatment plants, and some of the raw sewage bypasses the plant, ending up in Lake Michigan. Sewage makes the water dangerous and lethal to fish and other aquatic organisms. It also reduces water quality and the diversity of wildlife, especially sensitive species.

The issue of sewage pollution in the Great Lakes is not new. In 1964, an International Joint Commission report declared that the lower 26 miles of the Detroit River, which flows into Lake Erie, were "polluted bacteriologically, chemically, physically, and biologically so as to interfere with municipal water supplies, recreation, fish and wildlife propagation, and navigation." This report contributed to the 1970 declaration that "Lake Erie was dead," bringing attention to the severe pollution problems of the Great lakes at the time.

To address the issue of sewage bypassing treatment plants during heavy rainstorms, two solutions have been proposed: separating the storm and sewage systems or installing holding tanks to trap the overflow until it can be treated. By implementing these solutions, the amount of raw sewage entering the Great Lakes can be significantly reduced, improving water quality and protecting the diverse wildlife that depends on these lakes.

In addition to sewage, the Great Lakes face pollution from other sources, including industrial waste, agricultural runoff, and plastic waste. These pollutants have severe ecological and human health impacts, and addressing them requires a collective effort from governments, businesses, and individuals.

Agricultural and urban runoff

Urban and agricultural runoff, also known as non-point pollution, is the most significant source of pollution in the Great Lakes. 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. This area is referred to as the Great Lakes Basin.

Agricultural non-point pollution comes primarily from chemical fertilizers and manure, which flow into waterways from farm fields during rainfall. This runoff can contain pathogens, bacteria, and nutrients like nitrogen and phosphorus. While these nutrients are vital for growing plants, an excess in waterways can have disastrous results, fueling harmful algal blooms that can make water toxic to wildlife and people. When these blooms die, the decomposing algae use up oxygen in the water, creating "dead zones" where fish and other aquatic creatures cannot live. In 2014, nearly half a million people lost access to safe tap water for up to a week due to toxic algae contamination in western Lake Erie.

Urban non-point source pollution comes from nutrients, sediment, and bacteria that find their way into the Great Lakes through stormwater runoff from streets, parking lots, lawns, driveways, and roofs. Increased urbanization in the Great Lakes Basin has resulted in a substantial growth of impermeable surfaces, leading to larger volumes of runoff into the lakes. In addition, pollutants such as nutrients are deposited from the atmosphere into the Great Lakes waters, with atmospheric deposition being one of the largest non-point sources of nitrogen. These gases are released from agriculture and the burning of fossil fuels.

Addressing runoff pollution is a top priority for the United States and Canada as they consider revisions to the Great Lakes Water Quality Agreement. The Alliance for the Great Lakes is advocating for regulations at the state and local levels to mandate, incentivize, and prioritize best practices to limit farm runoff. They are also working with partners at the local level to find community-led solutions and shape solutions at the national and local levels. One goal is to tie funding for agricultural practices to clean water outcomes, requiring agricultural producers receiving federal funding for conservation programs to demonstrate a measurable reduction in pollution running off their lands.

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