Summary of Great Lakes Research

Environmental and ecological problems in the Great Lakes Basin are not only a regional problem, but a national and international one as well. The governments of both the United States and Canada have recognized that there is a price to be paid for what has been placed in, and demanded of, the lakes. The Great Lakes Basin is home to more than one-tenth the population of the United States and one-quarter the population of Canada, for a total combined population of over thirty million people. No region in all of North America has served humans better. But, for almost a century, humans have poured sewage, fertilizers, pesticides, and chemical wastes into the lake waters. In addition, humans have reduced many fish populations, altered and disturbed the natural ecosystems and wetlands, and introduced exotic, non-native species into the basin. (Skinner, 2002; Cobb, 1987)

As trustees of the Basin's natural resources, the Great Lakes States and Provinces have a shared duty to protect, conserve, and manage the renewable but finite waters of the Great Lakes Basin for the use, benefit, and enjoyment of all their citizens, including generations yet to come. While many of today's environmental issues are complex (i.e. the impact of persistent toxic substances on fish and human health, water level fluctuations, water diversion and usage, sediment contamination and transport, invasions of non-native species, fish health, climate and air impacts, and shoreline and watershed development), the most effective means of protecting, conserving, and managing the water resources of the Great Lakes is through the joint pursuit of unified and cooperative principles, policies, and programs mutually agreed to, enacted upon, and adhered to by each and every Great Lakes State and Province. (Botts and Krushelnicki, 1995; Flint, 1989; Skinner, 2002)

This survey project presents and discusses the major current interests and areas of research going on around the Great Lakes. The major topics include toxic chemicals, sediment contamination and transport, water levels, water diversion, invasive and exotic species, fish health, and urban sprawl and recreation. For each of these topics, some background information is presented along with a discussion of what has been done. Then, the research and studies that are presently being conducted are described and discussed. Lastly, the direction of future research and what needs to be done is presented, along with some established target completion dates.

With the large number of researchers and agencies collecting a vast quantity of data and information, it is easy for research efforts and data to overlap and/or be duplicated. Therefore, associated with the research survey, an analysis of how to store, access, manage, and share the data and information collected is presented. A networked resource system will play a key role in facilitating the sharing of information and data and inhibit unnecessary overlapping of tests and research.

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Introduction

The Great Lakes are constantly changing as a result of variations in the physical, chemical, biological, and human activity processes. The investigation for this project is a survey of the Great Lakes current research. The focus of the survey is on the research and studies currently being conducted in the Great Lakes, along with the current areas of interest associated with these studies. As part of this project, currently available data from various types of research and modeling will be presented along with suggested future research. A particular focus of interest is placed on toxic loading, invasive species, and water level and diversion information.

Description of the Great Lakes and Location

The Great Lakes are very important to everyone in the basin area. The Great Lakes Basin is home to more than one-tenth the population of the United States and over one-quarter the population of Canada, for a total combined population of over thirty million people. In addition to their beauty, the lakes not only provide water for consumption but also serve for transportation, recreation, power generation, and many other uses. The Great Lakes Basin includes approximately 300,000 square miles and covers parts of two countries. Lakes Superior, Michigan, Huron, Erie and Ontario, along with the connecting rivers and channels, compose the Great Lakes Basin system, which is located along the eastern international boundary between Canada and the United States. The international boundary between Canada and the United States runs right down the middle of the Great Lakes, with the exception of Lake Michigan, which lies entirely within the Unites States. As can be seen in Figure 1, the Great Lakes Basin includes portions of Minnesota, Wisconsin, Illinois, Indiana, Michigan, Ohio, Pennsylvania, and New York; as well as the provinces of Ontario and Quebec. (Botts and Krushelnicki, 1995; Sellinger, 2001; Skinner, 2002)

Source: GLIN website

Figure 1 – The Great Lakes region (back to top)

The Great Lakes contain almost 95 percent of the surface water in the United States and 20 percent of the earth’s surface fresh water. The Great Lakes contain approximately 6x10¹⁵ (six quadrillion) gallons of water. For contrast, spread evenly across the contiguous 48 states, the water from the lakes would form a column almost ten feet deep. In general, the outflow from the Great Lakes is small in comparison to the large total volume of water. Amazingly, less than one percent of the total volume of water is discharged annually into the Atlantic Ocean. (Botts and Krushelnicki, 1995; Skinner, 2002; SOGL, 2001; Kurth, 2002a).

Lake Superior, the largest body of fresh water in North America, forms the headwaters for the majestic Great Lakes waterway system. The water flows out the lake's southeastern tip down the St. Marys River, a 60-mile channel that drops more than 20 feet in water elevation from Lake Superior to Lake Huron. Lake Huron and Lake Michigan, which actually are two halves of one lake, are essentially at the same water elevation and are interconnected by the deep Straits of Mackinac. Water flows southward out the southern tip of Lake Huron down the St. Clair River, through Lake St. Clair and down the Detroit River to Lake Erie. The rivers form a 90-mile channel that flows, dropping less than ten feet, from Lake Huron to Lake Erie. Leaving Lake Erie, the water flows north via the Niagara River, a 37-mile channel that connects Lake Erie and Lake Ontario. Near the end of the river is the mighty Niagara Falls – an over 200 foot drop – that accounts for the majority of the 325 foot total drop in elevation between the two lakes. From Lake Ontario, the St. Lawrence Seaway and St. Lawrence River flow approximately 590 miles northeasterly, dropping nearly 250 feet in elevation, to the salty Atlantic Ocean. In total, water travels over 2,300 miles from the west point of Lake Superior to the end of the St. Lawrence. The Great Lakes and their connecting channels are shown in Figure 2. (Gauthier, 1999; Wisconsin Sea Grant Website).

Source: USACOE website

Figure 2 – The Great Lakes (back to top)

The Great Lakes were first utilized at the conclusion of the War of 1812 when the battles for territory abruptly ended as the warriors became, or gave way to, the entrepreneurs, farmers, and laborers of modern industrialization. Thus began the massive city and nation building that we now enjoy. The lake waterways were the major routes of trade between the developing cities, and during the following 150 years the development of the area proceeded with great haste. Today, the international shipping trade annually transports over 50 million tons of cargo, which generates over 50 percent of the total manufacturing output of the United States. The main commodities shipped within the Great Lakes region are coal, iron ore, grain, and petroleum products. (Botts and Krushelnicki, 1995; Skinner, 2002).

Historically, the major industries around the lakes produced paper, chemical, steel, automobile, and other manufactured products. A large portion of the steel industry is concentrated around the lake area because the iron ore, coal, and limestone needed for steel production are relatively close and are easily transported around the region. The majority of paper making in the United States occurs around the upper lakes. Chemical industries developed due to cheap electricity costs around the basin. However, all of these industries produce a large amount of waste. Throughout the nineteenth century and the early part of the twentieth century, industrial waste was dumped into the lake waters. Eventually, problems emerged and the threat to public health prompted the United States and Canadian governments to address the situation. (Botts and Krushelnicki, 1995).

Many of the hazards to human and environmental health due to industrial pollution were not recognized until the late twentieth century. The clean-up efforts around the Great Lakes region require cooperation and capital among the states, provinces, and federal government agencies. However, Great Lakes management is complicated due to the international cooperation required to effectively manage the ecosystem. Pollution prevention measures include clean-up plans to properly deal with the wastes. (Botts and Krushelnicki, 1995)

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Overview and History of the Great Lakes

The Great Lakes have played an important role in the settlement and development of the region. The waves of immigrants to the Great Lakes area since the late nineteenth century have exploited the region through logging, farming, commercial fishing, mining, and industrialization. This has led to profound changes in the ecological system. The intense logging has removed much of the shade and tight soil from the area. The sawmills processing lumber dumped sawdust and other bi-products into the nearby streams and rivers, clogging these waterways. In addition, streams and lake shorelines were littered with debris and sediment. As farming activities commenced, exposed soils were washed away and deposited in streams, rivers, and other lake tributaries. The onset of commercial fishing has reduced the abundance of fish, and in some cases has caused the extinction of a few species. The untreated waste products from early and late industrialization has degraded the local rivers and the lakes, while the growing urbanization that accompanied the industrialization lead to nuisance conditions along the shore areas. (Botts and Krushelnicki, 1995)

Lake Superior is surrounded mostly by forested land with sparse human population; thus, relatively few pollutants enter it from the surrounding land. However, airborne/atmospheric pollutants are constantly entering the lake. Lake Huron is more populated than Lake Superior, but is primarily used for recreation and has little industry. Pollutants are introduced directly by human activities. Lake Michigan generally has two different regions. The first is the less developed and sparsely populated northern region, used primarily for recreation, and the second is the mostly urbanized and active southern region. The majority of the pollutants introduced to the lake are in the southern region and are the direct result of human activities. Lake Erie is surrounded with fertile soil and is therefore intensively farmed, but is also used for recreation. Approximately one-third the population of the Great Lakes Basin resides around Lake Erie. Lake Erie receives considerable runoff from the agricultural areas surrounding it. This runoff is the primary source of pollution to the lake. However, other direct methods also contribute to the pollution, as this lake is exposed to the greatest stress not only because of its size but because of its urbanization and agricultural intensity as well. Lake Ontario, like Lake Michigan, is used for both recreation and industry. The vast majority of industrial facilities along the shores contribute most of the pollution. However, other significant factors of pollution also exist. (Botts and Krushelnicki, 1995)

By the mid-1960s, the growing concern about the overall quality of the Great Lakes led to the development of controls and regulatory mandates. During the 1970s, it became apparent that pollution caused by persistent toxic substances was harming Great Lake species and posing risks to human and wildlife consumers of fish. In addition, construction of municipal sewage treatment facilities also began. By the late 1970s, these initiatives began having a dramatic improvement on the quality of water within the Great Lakes. This improvement continued through the 1980s and 1990s. (Botts and Krushelnicki, 1995)

Today, the Great Lakes are a shared multipurpose resource used and managed at every level of government from local to international, even though they are still recovering from the effects of decades of pollution and neglect. Two federal governments, eight states and two provinces share the basin and hundreds of governmental entities are charged with some aspect of the resource management task. The incredible level and amount of cooperation that is required between two large and independent countries, which is so prevalent today, has taken many years to accomplish. It started in 1905, with the joint creation of the International Waterways Commission by the governments of both the United States and Canada. The commission was created to address water level effects and flow diversion resulting from the generation of electricity by hydropower that was beginning within the lake basins, and to advise the governments of both countries on lake water levels and related flows. In 1909, the commission signed the Boundary Waters Treaty that instituted the International Joint Commission. This treaty provides the means to overcome any disputes arising over water quality and/or quantity concerning the water boundary between the two countries. The International Joint Commission is an independent international organization charged with preventing and resolving disputes over the use of water(s) shared by the United States and Canada, and was given authority to generate binding binational decisions concerning the use of boundary waters and any associated issues. The International Joint Commission is required to monitor and assess progress made pursuant to the Great Lakes Water Quality Agreement, in particular the adequacy of actions by the two federal governments, the province of Ontario, and the eight Great Lakes states. (International Joint Commission Website)

The International Joint Commission investigates and reports on trans-boundary air and water pollution, persistent toxic substances, exotic species, and other matters of common concern along the international boundary. The commission, when requested by the two federal governments, also provides advice on matters affecting the shared environment. In addition, under the Boundary Waters Treaty, the commission approves projects, such as dams or water diversions, which affect water levels and flows along the boundary. The commission fulfills this responsibility by reporting information every two years. The first biennial report was released in 1981. Since its inception, the majority of the commission’s efforts have gone towards advising governments about current problems and concerns around the lakes. (Botts and Krushelnicki, 1995; Environment Canada’s Website)

Studies conducted by the International Joint Commission during the 1940s and 1960s, but promulgated in 1970, concluded that phosphorus was the reason for excessive eutrophication within the lower lakes. As a result of the study, the commission proposed basin-wide controls to reduce phosphorus loading in Lake Erie and implemented lake clean up. That recommendation lead to the passing of the Great Lakes Water Quality Agreement in 1972. In April 1972, then-Prime Minister Trudeau and then-President Nixon signed the Great Lakes Water Quality Agreement. This milestone event committed Canada and the United States to address and control pollution in the Great Lakes and to clean up waste from industries and communities. This agreement established common water-quality objectives between the two countries and showed that binational management could be accomplished despite the complex jurisdictional issues. The major issue at that time was phosphorus over-enrichment. Since then, phosphorus loads have been reduced in Lake Superior, Lake Huron, and Lake Michigan to below the levels required in the agreement. In addition, Lake Erie and Lake Ontario are very close to the specified levels. Thus, the control of phosphorus in the Great Lakes represents successful international cooperation in producing positive environmental results. (Botts and Krushelnicki, 1995; Environment Canada’s Website)

Continuing in 1978, a second Great Lakes Water Quality Agreement was signed which built upon the results of the earlier agreement. In contrast to the 1972 agreement, the new agreement called for the restoration of the chemical, physical, and biological integrity of the Great Lakes ecosystem. This agreement also called for the virtual elimination of the discharging of persistent toxic chemicals based on the irreversible damage of the substances. The countries specifically committed themselves to rid the Great Lakes of persistent toxic substances - substances that linger in the environment for long periods of time and can potentially poison food sources for both animals and humans. (Botts and Krushelnicki, 1995; Environment Canada’s Website)

By the mid 1980s, it was obvious to both countries that the Great Lakes were the most important natural resource for millions of their citizens. In 1986, the Water Resources Development Act was promulgated by the Congress of the United States, which enacted a policy to protect the quantity of water available in the Great Lakes. As amended in September 2000, the Water Resources Development Act is a water conservation and resource improvement decision that was implemented to prohibit water diversion and/or export out of the Great Lake Basin unless approved by the Governors of each of the Great Lake States. In 1987, Canada and the United States signed the 1987 Protocol, which updated the 1978 Great Lakes Water Quality Agreement to strengthen existing pollution controls and add new ones. The 1987 Protocol also introduced other new annexes focusing on non-point contaminant sources, contaminated sediment, airborne toxic substances, contaminated groundwater, and associated research and development. The pertinent annexes addressed include Annex 2 (Remedial Action Plans and Lakewide Management Plans), Annexes 4, 5, 6, 8 and 9 (The Coast Guard Annexes), Annex 11 (Surveillance and Monitoring), Annex 12 (Persistent Toxic Substances), Annex 13 (Pollution from Non-point Sources), Annex 14 (Contaminated Sediment), and Annex 15 (Airborne Toxic Substances). Emphasis was placed on the importance of human and aquatic ecosystem health. Based on the Great Lakes Water Quality Agreement, 43 Areas of Concern were identified in the Great Lakes Basin Ecosystem. Twenty-six are located within the United States, twelve are located within Canada, and five are bordered on both countries. These Areas of Concern are isolated geographical locations where serious problems remain, where water or living organisms are adversely affected, or where environmental standards are not met. The purpose of identifying these areas is to encourage local jurisdictions to rehabilitate these problem areas and restore them to their natural state. The majority of these areas are located near the mouths of tributaries and connecting lake channels around cities and industries. The severely degraded geographic locations of Areas of Concern in the Great Lakes Basin are shown in Figure 3 (Botts and Krushelnicki, 1995; Environment Canada’s Website; Michigan DEQ, 2000; International Joint Commission Website).

Source: Environmental Canada’s RAP website

Figure 3 – Areas of Concern around the Great Lakes basin (back to top)

In addition, the 1987 Protocol introduced provisions to develop and implement Remedial Action Plans and Lakewide Management Plans. These Remedial Action Plans and Lakewide Management Plans are providing the vehicles for delivering toxic reduction activities both lakewide and at local hotspots. Remedial Action Plans focus on geographic areas of concern by taking a unique ecosystem approach and draw upon broad local community involvement to address problems. Each Remedial Action Plan identifies the nature, cause, and extent of the environmental problems within the area. Remedial Action Plans identify when specific remedial actions are to be taken, and who is responsible for implementing them. Remedial Action Plans are crucial for restoring the ecosystems in the Areas of Concern. A Lakewide Management Plan is a plan of action to assess, restore, protect, and monitor the beneficial uses and ecosystem health of a particular Great Lake and to serve as a mechanism to address various ecosystem stressors. Lakewide Management Plans are used to coordinate the work of all the government and non-government parties working to improve the lake ecosystem. The Lakewide Management Plans are designed to improve the environmental quality of the open waters of each of the Great Lakes, with a particular focus on Critical Pollutants. The eight Great Lakes States and the Province of Ontario have committed to further developing and implementing the Remedial Action Plans and the Lakewide Management Plans to restore beneficial uses in each Area of Concern within their political boundaries. (Botts and Krushelnicki, 1995; Environment Canada’s Website; Skinner, 2002; Elster, 2001; International Joint Commission Website)

In 1989 the Canadian government initiated the Great Lakes Action Plan, a five-year trial lasting until 1994. It was designed to accelerate the cleanup of contaminated areas and prevent future pollution, as well as to support scientific research and public consultation. In 1994, at the end of the five-year trial period, the federal governments of both Canada and the United States announced a subsequent six-year plan, Great Lakes 2000, to continue its work and reinforce these issues. The culmination of the evolving government and management regulations, and the increase in public awareness and involvement, have resulted in an unprecedented improvement in the overall quality of the Great Lakes Basin. A good example is the April 1997 adoption of the Great Lakes Binational Toxics Strategy for the virtual elimination of persistent toxic substances in the Great Lakes Basin by the governments of Canada and the United States. As further actions are taken to continue the quality improvement and other steps are implemented to secure the gains made, the overall health and habitats of the ecosystem will prosper. (Botts and Krushelnicki, 1995; Ullrich, 2000)

In addition to the 1987 Protocol, both governments also established a policy to report the on-going status of the Great Lakes. These biennial reports are commonly known as “The State of the Great Lakes”(SOGL) and are subsequently the center of discussions during the State of the Lakes Ecosystem Conferences, which were established by both governments in 1992. The conferences are an intensive binational effort directed toward establishing a consistent, easily understood set of ecosystem indicators to allow for more coordinated monitoring and better reporting on progress achieved under the Great Lakes Water Quality Agreement. The chief objectives of the conferences are: assessing the state of the Great Lakes based on indicators; strengthening environmental management decision-making concerning the Great Lakes; and providing a forum to communicate and network with and among all the Great Lakes stakeholders. According to Dr. Harvey Shear, a science advisor for Environment Canada, the preferred method to track the condition of the ecosystem is through a series of indicators. “By using a set of easily understood indicators, it will become easier to assess how far we have come and how much farther we have to go to fully address the complex problems facing the Great Lakes.” The indicators are categorized into six major groups: open and nearshore waters, coastal wetlands, nearshore terrestrial areas, human health, land use, and societal. For each compartment, among other things, persistent toxic chemicals, exotic invasive species, nutrient loads, habitat, and climate changes will be evaluated. (SOGL, 2001)

In 1996, a comprehensive set of indicators was developed to assist progress reporting. The two countries intend to use the indicators as a way to justify funding for future research since they will measure how close they are to achieving the goal. There are currently 80 indicators that have been developed by scientists over the past few years to create a picture of the health of the Great Lakes Basin. However, not all of the proposed indicators are being monitored. Only 33 of the 80 indicators have enough data readily available to report findings and present information during the State of the Lakes Ecosystem Conferences. The indicators are expected to greatly influence future monitoring and data gathering. The current indicator list is expected to be refined over the next decade, the 33 current indicators are presented in Table 1. The total number of indicators with sufficient data to draw reasonable conclusions is expected to increase significantly in the years to come. (Environment Canada’s Website; SOGL, 2001).

Nearshore and Open Waters (13)	Land Use (4)
Atmospheric deposition of toxic chemicals Contaminants in colonial nesting waterbirds Deformities, eroded fins, lesions and tumors in fish Hexagenia Lake Trout Native unionid mussels Phosphorus concentrations and loadings Phytoplankton populations Preyfish populations Scud Spawning Sea Lamprey abundance Walleye Zooplankton populations	Brownfield redevelopment Mass transportation Sustainable agricultural practices Urban density
	Human Health (4)
	Air quality Chemical contaminants in edible fish tissue Drinking water quality E.coli and fecal coliform in recreational waters
	Nearshore Terrestrial (4)
	Area, quality, and protection of alvar communities Extent of hardened shoreline Contaminants affecting productivity of bald eagles Population monitoring and contaminants affecting the American Otter

Coastal Wetlands (5)
Amphibian diversity and abundance Coastal wetland area by type Contaminants in snapping turtle eggs Effect of water fluctuations Wetland dependent bird diversity and abundance


	Societal (2)
	Economic Prosperity Water use

Unbounded (1)
Acid rain
Acid rain

Table 1 – 33 Current indicators (SOLEC, 2001) (back to top)

Description of the Great Lakes Research Survey

Scientists from a variety of disciplines representing numerous state, provincial, and federal government agencies, along with countless academic institutions, have amassed scientific and technical knowledge on the Great Lakes ecosystem in support of basin improvement, public education, and policy formation. The scientists are involved in research focusing on physical, chemical, and biological processes in lakes. The end result of their research will be an excellent understanding of the lakes, along with their inhabitants, and how they respond to human activities and the promulgation of new policies or legislation for the protection of the Great Lakes Basin. (Center for Great Lakes Studies, University of Wisconsin-Milwaukee Website)

The main intention of this report is to present information on the current research efforts throughout the basin and present suggestions on the direction of future research and the public policies affecting it. However, some background and historic information was deemed pertinent in understanding how the current research evolved. It is intended to present where the major focus around the basin has been and to suggest the direction it should go in the near future. The knowledge gained from this study, hopefully, will be applied to assist proper management of future lake activities and research. In addition, it could be used to minimize the overlapping of research efforts and assist in maximizing the use of current funding. (Center for Great Lakes Studies, University of Wisconsin-Milwaukee Website)

Managing water resources is a major international effort that includes biological, ecological, hydrologic, chemical, engineering, socioeconomic, law and policy, education, and planning/management research components. The management confusion generated by the large number of government and academic research has arisen due to the void resulting from the non-centralization of the astronomical volume of data collected so far. Section VI of this report presents suggestions to help organize the information collected and how to categorize it. (Center for Great Lakes Studies, University of Wisconsin-Milwaukee Website)

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Current interests around the Great Lakes

Over the centuries, the Great Lakes appeared invulnerable because of their seemingly infinite size. Up until the 1950s, the lakes were considered too immense to be adversely affected by human activity, but it has been realized that they have been pushed to their limits. The increasing burdens placed on them due to population growth, industry, and even recreation have disturbed the delicate balance and harmony of their environment. The past few decades have shown how wrong we were. (Cobb, 1987)

Toxic chemical loading

As industrialization and urbanization has increased over the past half century, new chemical substances have been introduced into the Great Lakes ecosystem. The continuous loading(s) of contaminants and nutrients remains a problem throughout the Great Lakes Basin. The combination of synthetic fertilizers and nutrient-rich organic pollutants from sewage effluent and agricultural runoff has caused a disruption of biological activity by releasing large amounts of phosphorous, and other nutrients, into the lakes. The amount of biological activity and production within the lakes determines the balance of food and oxygen distribution within the ecosystem. These nutrients, especially phosphorus, initially stimulate the growth of algae and other beneficial plants. However, the overgrowth of the algae and plants causes depletion of the oxygen present in the water, resulting in their death and subsequent decay. The resulting lack of oxygen leads to the death of fish. Remedial actions initiated in the 1970s have reduced nutrient loadings and enhanced the role of food web interactions in improving water quality. Phosphorus concentration in the lakes is currently under control with most areas being at or below target limits. However, there are still some “hot spots” and strict adherence to existing targets must be implemented. The variable conditions that have a great affect on this balance are ambient temperature, amount of sunlight, water depth, water volume, and amount of nutrients. (Botts and Krushelnicki, 1995; SOGL, 1999 and 2001)

Man-made chemicals may be present in lake water at such low concentrations that even sensitive instruments fail to detect them. However, many of these chemicals do not break down in the environment and tend to bioaccumulate in water organisms. The concentrations are stored within the cell structures and become much higher in the living cells than in the open water. This accumulation is repeated at each level in the food chain and produces vastly increased chemical concentrations. This is referred to as biomagnification. The concentration of chemicals in the fatty tissues of top fish predators is usually millions of times higher than in the initial open water concentrations. This is important since humans are not only at the top of many food chains, but because they are consumers in the Great Lake chain as well. (Botts and Krushelnicki, 1995)

During the 1970s, it became apparent that pollution caused by persistent toxic substances was harming a variety of species and posing risks to human and wildlife consumers of fish. Persistent toxic substances resulting from human activity, particularly those that bioaccumulate, were targeted for reduction through a management approach to ultimately achieve naturally occurring levels. Several bird and fish species problems were identified stemming from the use of dichlorodiphenyltrichloroethane (DDT) and polychlorinated biphenyl’s (PCBs), very toxic and persistent chemicals. DDT and PCBs have since been banned, and other less toxic chemicals have been developed to replace them. (Great Lakes Binational Toxics Strategy, 1997)

Several factors make the Great Lakes particularly susceptible to the effects of persistent contaminants: (1) nearly closed system, (2) long water retention time, (3) low sedimentation rates, (4) low biological productivity, (5) low suspended solids concentrations, (6) presence of a largely self-contained fish and wildlife population, (7) heavy concentration of industries and large population centers surrounding the lakes, and (8) huge surface areas susceptible to airborne contaminants. (Great Lakes Binational Toxics Strategy, 1997; Botts and Krushelnicki, 1995)

The Lake Michigan Mass Balance Study is the largest toxic contaminant monitoring and modeling project ever undertaken. It was designed and created by the U.S. Environmental Protection Agency to answer questions that will help environmental managers make well informed, scientifically based decisions on reducing toxic pollutants. The Mass Balance Model will determine what effects reduction in pollutant loads will have on the lake and on contaminant levels in fish tissue. (Great Lakes Binational Toxics Strategy, 1997)

While surface water runoff is the major pathway for the majority of toxic substances to enter the lakes, research has discovered that many pollutants are also deposited from the atmosphere. Nutrients and toxic contaminants can be carried from far-off sources and deposited within the Basin. Long range transportation of these substances was confirmed by the PCBs and toxaphene discovered in fish within a remote part of Lake Superior that is isolated from all direct sources. Projected future climate changes could heavily impact ecological conditions, as a potentially warmer and drier climate will affect agricultural activities. (Botts and Krushelnicki, 1995; Skinner, 2002)

Pollutants entering the Great Lakes from the air constitute part of the ecosystem approach espoused in the Great Lakes Water Quality Agreement. In 1966, the Governments of Canada and the United States asked the International Joint Commission to monitor air quality along the entire Canada-United States boundary and, where appropriate, draw air pollution problems to their attention. The Commission subsequently established the International Air Quality Advisory Board. The role of the Board is to identify and provide advice on air pollution issues with trans-boundary implications. An initial action was to define the airshed of the boundary. This was done by analyzing the potential for air contaminants originating in one country to travel by prevailing winds across the border and impact the other country. The ten Board members possess expertise in various aspects of air pollution effects and control. Appointed by the International Joint Commission, they serve in their personal and professional capacities. The role of the Board is entirely advisory. (Environment Canada’s Website)

It has been postulated, through research and modeling, that air currents from Mexico, and even as far away as Russia, flow through the Great Lakes Basin bringing airborne chemicals and pollutants from their areas. The International Joint Commission estimates approximately 99 percent of all lead entering Lake Michigan, 97 percent entering Lake Superior, 94 percent entering Lake Huron, and up to 50 percent entering Lakes Erie and Ontario comes from the atmosphere. The atmospheric weather pattern around the continental Great Lakes is the culmination of mixed airflows coming into the region from various directions. The prevailing air mass movement is from west to east across the region. The air masses range from Maritime-Tropical from the Gulf of Mexico, to Continental-Polar from the Arctic North. The atmosphere represents a boundary-less region for the deposition of toxic chemicals to be introduced to the basin. These atmospheric contaminants are deposited by both wet and dry deposition. Wet deposition is the washing of contaminants out of the atmosphere through rain, snow and hail. During dry deposition, contaminants are blown by wind in the form of dust and debris. Approximately 90 percent of PCBs introduced to Lake Superior are carried through the atmosphere. In addition, 63 percent of the PCBs introduced to Lake Huron and 58 percent introduced to Lake Michigan were airborne. The Integrated Atmospheric Deposition Network was established in 1999 as a joint U.S. and Canada committee to evaluate and monitor the atmospheric deposition of toxic pollutants into the Great Lakes Basin. The atmospheric deposition of mercury and PCBs are the major concerns presently. Approximately 200 tons of mercury is deposited in the basin each year, primarily from waste incinerators and chlorine production. Additionally, over 4,000 tons of PCBs are deposited each year. (Henry, 1994; SOGL, 1999; Skinner, 2002)

Water levels

Water levels around the Great Lakes Basin have been measured since the 1840s, and initial indications show lake level fluctuations occur on an average of 160 years, with sub-fluctuations on an average of 33 years. However, the amplitude of water level fluctuations has decreased significantly since the opening of the St. Lawrence Seaway in 1959. Lake levels are determined by precipitation, upstream inflows, surface water runoff, evaporation, diversions and water-level regulation. A mass balance between the amount of water entering the watershed and the amount exiting the watershed shows the relationship of these variables on lake water levels. Climate conditions control the amount of precipitation as well as the rate of evaporation. These two factors are the primary factors influencing lake water levels. The lakes depend on a large influx of water from the surrounding areas over winter. When above-average precipitation combined with cool and cloudy weather occurs, the water levels rise. Conversely, long periods of below-average precipitation with warmer weather result in lower water levels. In addition, during the winter months, in the absence of an ice layer, water will evaporate out of the lakes. (Gauthier, 1999; Kurth, 2002a; SOGL, 2001)

In general, there are three types of water-level fluctuations; short-term, seasonal, and long-term. Short-term fluctuations, ranging from a few hours to several days, are generally caused by storms, ice build-up, and excessive plant growth. Seasonal fluctuations happen yearly as the Great Lakes Basin experiences four distinct seasonal climates. The seasonal fluctuations in water level are the most common and range from 16 to 20 inches between the winter month lows and the summer month highs. As seasons change, the wind velocities and directions also change, altering the path of waves. Annual, or seasonal, variations in water levels are mainly due to differences between the volume of water gained during the summer months and the volume of water lost during the winter months. Long-term fluctuations occur over many years, and are mostly the result of atmospheric climate changes that affect precipitation and plate tectonic activity. Climate change is becoming more extreme, and that could lead to larger fluctuations in the lake levels. Crustal movement has a lasting semi-permanent affect on lake water levels. Mostly the result of upward rebounding, the northern portions of the basin have been rising while the southern portions have been predominately stationary. As a result, the Great Lakes Basin is becoming permanently tipped. The obvious result of the crustal tipping is a lowering of lake levels in Lake Superior and the northern portions of Lakes Huron and Michigan, and a subsequent rise in lake levels in the southern parts of Lakes Huron and Michigan, along with Lakes Erie and Ontario. (Gauthier, 1999)

Historically, the lake levels hit extreme lows in the mid-1920s, the mid-1930s, and the mid-1960s. Record highs were recorded in the late-1870s, the late 1920s, the early-1950s, the early-1970s, the mid-1980s, and the mid-1990s. However, because of other factors, water levels have been dropping over the past few years. Dramatic declines in lake water levels could compromise the ecological health of the entire basin and create economic concern for multiple industries around the lakes. Flooding and erosion damage is also a concern and leads to public pressure to regulate lake levels through diversion and control structures. (Gauthier, 1999; Botts and Krushelnicki, 1995)

The Great Lakes Charter of 1985 was formed to conserve the levels and flows of the Great Lakes, along with their tributary and connecting waters; to protect and conserve the environmental balance of the Great Lakes Basin ecosystem; to provide for cooperative programs and management of the water resources of the Great Lakes Basin through States and Provinces; to ensure and protect present developments within the region; and to provide a secure foundation for future investment and development within the region. This is done in accordance with the guidelines established by the International Joint Commission, which has binational jurisdiction in controlling the boundary waters. Currently, water levels and diversion are controlled at two points in the Great Lakes Basin: at Sault Saint Marie where Lake Superior empties into the St. Marys River, and near Cornwall, Ontario, some 100 miles from where Lake Ontario empties into the St. Lawrence River. The International Joint Commission regulates the flow through these stations, under the Lake Superior Board of Control and the International St. Lawrence River Board, respectively. (Botts and Krushelnicki, 1995; US Environmental Protection Agency Website)

The lake water levels are the responsibility of the International Joint Commission and are to comply with the terms of the Boundary Water Treaty set in 1909. The International Joint Commission manages water levels and flows for navigational and hydropower production. In 1973, after almost ten years of study, the International Joint Commission concluded that the high costs of developing, building, and maintaining a system of engineering controls for regulating water levels in the lakes would not be feasible. (Botts and Krushelnicki, 1995)

Dredging has also had an affect on water levels. As ships on the Great Lakes grew larger, it became necessary to dredge the rivers and channels to meet the new depth requirements, thus affecting water levels. Dredging activities conducted to enlarge and deepen existing navigational channels were performed between 1930 and 1960. As a result of those activities, the water levels of Lake Michigan and Lake Huron have been permanently lowered by almost 16 inches. (Environment Canada’s Website; Gauthier, 1999)

While existing engineering flow controls and dredging activities have served to improve the usefulness of the lakes, the results of many surveys have concluded that any future engineering activities will be futile. That is because, by far, the major factors affecting water level fluctuations are precipitation, evaporation, upstream inflows, and runoff. The lakes require a large influx of water during the late winter months, and that has not been happening recently. Great Lakes water levels have dropped considerably the past few years, primarily due to meager snowfall during the winters and increased evaporation during the warmer summers. Water levels in the Great Lakes are now significantly below their historic averages. As shown in Figure 4, water levels are lower than normal but above their historic lows. Since 1997, Lakes Erie, Huron, and Michigan are down almost three feet, and Lakes Ontario and Superior, which are mechanically regulated, are down almost one foot. Decreases in water levels equates to over 60 trillion gallons of water. In February 2001, the Detroit News reported that Lake Superior was six inches lower than the previous year and was 13 inches below its long term average; Lakes Michigan and Huron were each down five inches and were about 23 inches lower than their long term averages; Lake Erie was down nine inches and Lake Ontario was down four inches from their long term averages. However, since June 2001, Lakes Michigan, Huron, and Erie are still 10 and 24 inches, respectively, above the record lows set in 1964 and 1934. (Gauthier, 1999; Sellinger, 2001; Pearce, 2001)

Figure 4 – Great Lake water level changes in the past few years (back to top)

Water diversion

Water diversion and consumption play a major part in affecting lake levels. Diversion is defined here as the removal of water from one watershed to a separate one. The majority of diverted water ends up in the Mississippi River, while most consumed water evaporates or is used in industrial cooling operations. However, a 1982 study by the International Joint Commission concluded that atmospheric conditions and changes have far more influence on water levels than human diversions. (Botts and Krushelnicki, 1995)

The waters of the Great Lakes Basin are interconnected and are part of a single hydrologic system. The multiple uses of these resources are for municipal, industrial, and agricultural water supply; mining; navigation; hydroelectric power and energy production; recreation; and the maintenance of fish and wildlife habitat for a balanced ecosystem are interdependent. Studies conducted by the International Joint Commission, the Great Lakes States and Provinces, and other agencies have found that without careful and prudent management, the future development of diversions and consumptive uses of the water resources of the Great Lakes Basin may have significant adverse impacts on the environment, economy, and welfare of the Great Lakes region. (Botts and Krushelnicki, 1995; SOGL, 2001)

While the majority of all water withdrawn is eventually returned, roughly two percent annually withdrawn is consumed. Water consumption, which is a form of diversion, is defined as water withdrawn from the watershed that is not returned. Examples of this include drinking water, irrigation water, and many industrial uses of water. The Great Lakes continue to be the source of drinking water for tens of millions of people. Tens of billions of gallons of water are drawn from the lakes per day for human use. The average household uses 100 gallons of water per day per person, while 100 times that is used by power generating facilities for both energy generation and equipment cooling. In 1999, more than 4,250 cubic feet of water was lost from the Great Lakes Basin per second due to consumptive use. The amount will increase since the population on the Canadian side of the Great Lakes Basin is expected to rise by about 20 percent, or an estimated 12 million people, by 2020 while the United States population is expected to remain constant. (Gauthier, 1999)

Non-consumptive water is the water that is returned to the watershed after it has been diverted and used. Examples of this include recreation activities, transportation, and direct hydroelectric power generation. During periods of significant water level decrease and/or diversion, power generation is substantially affected. (Gauthier, 1999)

There are three main areas in the Great Lakes where water is diverted. The first area is at the Ogoki and Long Lac diversions, north of Lake Superior. Water is taken from the Hudson Bay watershed to drive hydroelectric power plants on rivers feeding Lake Superior. The result is an increase in the amount of water that flows into Lake Superior of about 5,900 cubic feet of water per second. The second water diversion is the Lake Michigan diversion near Chicago which is used for water supply, sewage disposal and commercial navigation purposes. Water is removed from Lake Michigan at the rate of 3,200 cubic feet per second and is sent through the Chicago Sanitary and Ship Canal and eventually discharged to the Mississippi River where it flows into the Gulf of Mexico. The third diversion point is the Welland Canal diversion around Niagara Falls. Water is diverted for the generation of hydroelectric power and for shipping. The canal diverts some 9,000 cubic feet of water per second from Lake Erie. However, almost all of it is eventually discharged into Lake Ontario. Meanwhile, withdrawals and consumptive use appears to have slowed. Although the Long Lac and Ogoki diversions have been steadily increasing the water supply to Lake Superior over the years, resulting in a nearly one inch rise in water level, the other diversions have reduced Lake Michigan's and Lake Huron's by one-half inch. At the present time, more water is diverted into the system than is taken out. (Environment Canada’s Website)

In addition, over the past few years the diversion of water outside the basin has become a big issue as states outside the basin are trying to get water diverted for use in their areas. Public concern on the potential movement of freshwater beyond the Great Lakes Basin continues to grow. A large number of proposals exist to initiate the sale of water to the fast-growing, water-poor areas of the U.S. (Midwest and Southwest). The massive engineering needed to accomplish this has been proposed to supply water to these areas. If they are successful, that water would be considered consumed and excluded from the basin volumes. In the past, all the Great Lake States and the Province of Ontario have opposed these ideas. The Great Lakes Commission unanimously adopted a policy position opposing the withdrawal of Great Lakes water for overseas export at their 1998 Annual meeting. Many of the basin states, and the province of Ontario, oppose the removal of lake water and, in accordance with Section 504 of the Water Resource Development Act, bulk export or diversion from the Great Lakes cannot take place without the unanimous approval of all the Great Lakes Governors. In addition, an International Joint Commission report states that removing bulk quantities of water reduces the resilience of the Great Lakes to withstand stress. To date, no regular trade has begun to ship water; however, caution is warranted regarding future water uses. Both the U.S. and Canadian governments remain concerned that existing management principles and conservation measures may be inadequate to ensure future sustainable use of the lakes. (Environment Canada’s Website; Skinner, 2002; Gauthier, 1999; Botts and Krushelnicki, 1995; Elster, 2001; Michigan DEQ, 2000)