Lakes and inland seas 1. Restoring the Great Lakes and their rivers

Posted: 10 January 2001

Author: Henry Regier and Harvey Shear

Once a vast horn of plenty, the Great Lakes Basin has been badly affected by modern man's urban, industrial, commercial, intensive farming and other activities. But there is still hope for rehabilitating the Lakes and Rivers, as Henry Regier and Harvey Shear explain in this special report. Both authors have been involved in environmental conservation of the Basin, and Shear has organised and co-chaired the four biennial State of the Lakes Ecosystem Conferences, the first of which was held in Detroit in 1994.

The Great Lakes Basin ecosystem was once perceived to be a vast natural cornucopia in a generally benign climate. The Lakes from west to east (upstream to downstream) are Superior, Michigan, Huron (including Georgian Bay), Erie and Ontario. Short but large interconnecting channels and Rivers direct the flow of water towards the Gulf of St Lawrence, and thence to the North Atlantic Ocean. With respect to geology, climate, ecology and culture, it strongly resembles the Baltic Basin of Europe.

In the satellite photograph of the basin, the false colours tell a story of human settlement and its effect on the basin. The red areas represent cities, and the orange, largely agricultural areas. Over the past two centuries, the European settlers to the basin have been deeply committed to industrial and commercial 'progress'. This has occurred more often than not at the expense of the Native Peoples and the natural environment. Native Peoples who were not assimilated into European culture were suppressed and confined to reserves generally on lands not valued highly by the entrepreneurs and settlers.

Severely degraded

By the 1960s, all the waters in the areas adjacent to the red and orange parts of the basin had been severely degraded. Of many degraded locales, altogether 43 Areas of Concern were designated, where a valued natural ecosystem had become transformed into a dangerous and unhealthy ecosystem. One of these areas (Collingwood Harbour) has been successfully rehabilitated and is now delisted. The worst areas, including Green Bay, Toronto Bay and the Niagara River, may not be delisted until well into the 21st Century.

In recent decades, the population of the US side of the basin has been stable to moderately declining, while the Canadian side has been increasing. Forecasts indicate that the Canadian population will increase by 1.5-2.0 million by 2020, mostly in Southern Ontario. The US population has moved to other industrial areas of the country such as the southwest, while the Canadian population has grown and urbanized at the expense of prime agricultural land, and the destruction of aquatic habitats such as wetlands. The Basin's population would have decreased more had it not been for immigrants from many parts of Asia and Europe. Concurrent with population changes has been a reduction in heavy industry. Environmental improvements resulted in part from environmental reform, and in part from corporate policy to locate elsewhere. Meanwhile Native Peoples have been reasserting Constitutional and Treaty rights to resources in large areas in which these rights were never ceded.

Human activities led increasingly to pollution of the Lakes. Problems associated with excess nutrient enrichment in Lakes Erie and Ontario prompted studies that led to a bi-national Agreement of 1972, and to a comprehensive attack on phosphorus in sewage effluent and in laundry detergents which cost billions of dollars. This led to a dramatic decline in phosphorus levels in Lakes Ontario and Erie.

Phosphorous problem

In the 1960s and 70s, agencies of governments generally interposed themselves between industrial and other users of the environment and the individuals and interest groups who felt harmed by those users. Americans developed a strongly legalistic approach to the fair resolution of those issues, while Canadians relied more on persuasion and coercion. By the 1990s, a more balanced mix of approaches was apparent in both countries.

A more insidious environmental problem has been that of persistent toxic contaminants. First identified as a problem by Rachel Carson in the early 1960s, pesticides were designed to kill harmful organisms. But they also killed non-target species. By the late 1960s, the adverse effects of persistent pesticides such as DDT, and also of radionuclides, were sufficiently understood to result in strong government programmes which have been locally successful.

Levels of these contaminants in the environment are now only a tiny fraction of their former levels. Dioxin is a by-product of pesticide manufacture; it occurred as impurities in early pesticide formulations and now leaches from buried wastes of the manufacturing industry, as well as entering the Great Lakes ecosystem via the atmosphere from distant sources.

Toxic contaminants

With respect to atmospheric transmission, in recent decades some contaminants are leaving the Basin's waters in greater quantities than are entering it. Unfortunately, the benefits of such degassing to the Great Lakes are offset globally by the transmission of some of these to more northerly waters.

As a means of addressing the contaminants issue, several kinds of policies have been fostered since the 197Os:

  • prevention of their release to the environment;

  • removal of highly contaminated material from hot spots and its destruction technologically;
  • treatment of contaminated sediments in situ

  • burial of contaminants in stable sediments, where gradual breakdown can occur;

  • educating people to be aware of the dangers of these substances and to take precautions to minimize exposure through, for example, warnings that identify which local fish are too contaminated to serve as food.

Each of these policies has been successful, in part. As social incentives to reform have displaced earlier legalistic disincentives, progress with the contaminant issue has been accelerating.

Herring gulls

The herring gull pictured here has an extra foot, probably as a result of residual contaminants in the food chain, altering the gull's genetic code at a very early stage of embryonic development. Herring gull Anomalies of this kind are still seen in numerous species of animals, but now at low frequencies, and at only a few sites around the Lakes. The fact that we see any deformities at all is partly a result of a large increase in populations of some sensitive species. In the 1970s there were few gulls around the lakes and now large breeding colonies exist, because reductions in pesticide and contaminant concentrations have allowed these and some other species to flourish.

There are scientists who fear that some humans are also being harmed by a new breed of contaminants - hormone-disrupting chemicals. These chemicals appear in the environment in very minute quantities, but have the capacity to disrupt the delicate hormone systems of mammals, amphibians and fish. They seem to affect individual organisms particularly in their earliest embryonic stages and then cause permanent harm that may be transmitted to future generations. European settlement in the basin has also resulted in the loss of some 80 per cent of the wetlands and much of the nearshore habitat near the urban centres. Valuable fish habitat was destroyed through removal of exposed gravel and rock, and by infilling for urban development. Governments and citizens are now acting to restore and protect those habitats which have not been irrevocably lost. People of the Great Lakes Basin use the aquatic system for many purposes including drinking water, discharge of biological waste, dilution of chemical waste, industrial process water, dissipation of industrial waste heat, transportation, generation of hydroelectric power, harvesting of fish and wildlife, recreation, and aesthetic appreciation.Great Lakes sceneLake Superior at sunset© John Downman/Hutchison LibraryInnovators on shared governance in the basin have come to understand the complex interaction between these uses and the need for an 'ecosystem approach'.

In practice, if not in legal theory, many users have acted under the assumption that the aquatic system of the Basin was no-one's property. Access to the resources was deemed to be open and free, and the onus to prove that a particular use caused harm lay with the individual who felt personally wronged. Legal constraints on these uses were introduced and gradually strengthened, use by use, by various levels of government in the Basin.

Since the early 1990s, rights and responsibilities for any use of the environment are being clarified in the context of the entire mix of interacting uses. The right to use the environment, and the accountability for doing so, are being made explicit, and are being administered in ways that cannot easily be ignored or misunderstood.

Management plan

But despite the clarification of rights and responsibilities, and the increased activity in rehabilitating the environment, there is no hope of ever going back to a near pristine state in the areas of the basin shown in orange or red on the satellite photo. Thus the aquatic ecosystems of the southern half of the Basin will remain strongly modified. Although there have been improvements in ecosystem quality over the past three decades, we have no idea what new ecological features will manifest themselves in these ecosystems in the next few decades.

The question "what sort of ecosystem do we want?" is being asked in the context of developing Lakewide Management Plans for each Lake. The answer for Lakes Erie and Ontario is difficult in that there are so many non-native species in these Lakes, and more will likely come, so that it may not be possible to achieve a particular ecosystem goal, even if society can agree on one. So far, we have lurched from crisis to crisis, fixing what we can. More is now expected, as reflected in the "Ecosystem Charter for the Great Lakes-St Lawrence Basin" recently created by a broad cross-section of interests in the Basin. In considering the question "what sort of ecosystem do we want?" we must also ask what is feasible. Current scenarios of climate warming need to be considered in terms of their effects on the Lakes. While the Lakes may not suffer as severe a negative impact as other parts of North America, there could well be increased demand to transport Great Lakes water to parched areas of the continent.

In addition, major migration into the Basin could occur, with all the negative environmental effects of a suddenly increased population. A precautionary "no regrets" policy to both climate warming and to the possible inflow of human migrants might involve the intensification of current environmental and political reforms. Meanwhile, appropriate efforts should be directed towards reversal of climate warming and to the prevention of conditions that would trigger large-scale human migrations out of their homelands.

Henry Regier is Professor Emeritus, University of Toronto. Dr Harvey Shear is Regional Science Adviser to Environment Canada-Ontario Region. For information on the state of the Great Lakes contact Harvey Shear (). For copies of the Ecosystem Charter for the Great Lakes-St. Lawrence River Basin contact the Great Lakes Commission, The Argus II Building, 400 Fourth St., Ann Arbor, MI 48103-4816, USA. Tel: +1 734 665 9135, Fax: +1 313 665 43 70, Email: