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A Guide to the GLWQA >
Where do we go from here?
Drafters of the original Great Lakes Water Quality Agreement anticipated that changes and adjustments would be needed in the Agreement based on experience, new science and a greater understanding of the Great Lakes Basin Ecosystem. They recognized that they didn't have all the answers, but knew that urgent, forceful action was needed. The governments responded with an extraordinary document, and in each revision to the Great Lakes Water Quality Agreement they continued to change and improve this historic model of international cooperation.
Consistent with Agreement provisions, the governments are required to initiate a comprehensive review of the Agreement early in 2006. This is an opportune time for such a review. Several collaborative initiatives are underway throughout the basin to protect and restore the Great Lakes Basin Ecosystem. While much good work has and is being done to achieve the Agreement's goals, some parts of the Agreement, such as some of the specific objectives for the concentrations of substances in water, are outdated and others have not worked as well as expected. One of the main purposes of the governments' review will be to consider which parts have worked well and which have not. They will also consider whether additional subjects should be addressed.
Experts have identified a number of serious challenges facing the Great Lakes now and into the future. A brief summary of some of these challenges follows.
Climate Change
Excess Nutrients
Aquatic Alien Invasive Species and Changes to the Biological Community
Chemical Contaminants and Their Effects
Shoreline Development and Urban Sprawl
Climate Change
Many experts believe that climate change, especially global warming, is already affecting the chemical, physical, and biological integrity of the Great Lakes Basin Ecosystem. The timing and significance of possible impacts are not well understood, but any alterations in water levels and water quality can affect to some degree the biological community including humans, wildlife, wetlands, and fish. Governments will need to consider whether climate change should be addressed in the Agreement.
Excess Nutrients
Inputs of nitrogen and phosphorous from point sources such as factories and sewage treatment plants have been largely controlled. Nonpoint sources such as stormwater runoff from farm fields or parking lots remain ongoing problems. Large-scale aquaculture can also lead to excess nutrients and other impacts. Combined sewer overflows and sanitary sewer bypasses also can result in increased concentrations of nutrients and other contaminants. Excess nutrients stimulate the growth of algae that can threaten the health of humans, fish, and wildlife and affect large areas such as the central basin of Lake Erie. They also cause taste and odor problems in drinking water, and foul beaches and swimming areas.
Aquatic Alien Invasive Species and Changes to the Biological Community
Approximately 170 aquatic alien invasive species, such as zebra mussels and sea lamprey, are not native to the Great Lakes ecosystem, and have dramatically impacted the ecology and economy of the lakes. These organisms were introduced from other continents or other parts of North America in a variety of ways, including the discharge of ballast water from ships, canals, and hull and equipment fouling. Native species and ecosystems have not always been capable of resisting infection, infestation, predation or competition from these invaders. Despite more than a decade of attention and action, such as mandatory ballast water exchange requirements in some jurisdictions, the introduction and spread of alien invasive species continues, and at least two new species arrive every year. The lack of common regulations in the two countries has slowed progress.
Chemical Contaminants and Their Effects
While levels of some chemical pollutants have declined over the last 20 to 25 years, emerging chemical issues continue to raise concerns for human and ecosystem health. Critical pollutants are still detected in open waters at levels that sometimes exceed the most stringent criteria designed to protect wildlife and humans who consume fish. For example, levels of polychlorinated biphenyls (PCBs) and dieldrin in open waters of Lake Ontario are approximately 100 times higher than their respective standards. Fish consumption advisories are in effect in all lakes and their tributaries. PCBs, dioxins, mercury, chlordane and DDT account for most of the advisories. Some of the newer classes of persistent chemicals may impair or disrupt the endocrine system, potentially interfering with development, reproduction and growth in certain species.
Shoreline Development and Urban Sprawl
If current trends continue, the impact of future growth of urban areas within the Great Lakes and St. Lawrence River basin will lead to continued shoreline development and urban sprawl, with or without increases in population. Both further degrade water quality by increasing runoff, air pollution, groundwater contamination, and reducing fish and wildlife habitat and wetlands.
These emerging issues are not specifically addressed by the current Agreement. The governments likely will consider these and other emerging issues in their review of the Agreement; they may choose to address them within a revised Agreement, or by a variety of other mechanisms and programs.
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