Great Lakes Water Quality Agreement Is Signed

The United States and Canada concluded an agreement that represented the first serious joint effort to solve the environmental problems of the Great Lakes.

Summary of Event

On April 15, 1972, U.S. president Richard M. Nixon and Canadian prime minister Pierre Trudeau signed the Great Lakes Water Quality Agreement (GLWQA) in Ottawa, Canada. The agreement, signed the same year as the U.S. Clean Water Act and the Canada Water Act, defined the common goals of the two nations with regard to the protection and restoration of the Great Lakes. The International Joint Commission (IJC) was given the charge of assisting both nations in implementing the goals, and two joint advisory boards, the Great Lakes Water Quality Board and the Great Lakes Science Research Board, were formed to assist the IJC. Great Lakes Water Quality Agreement (1972)
Pollution;international agreements
[kw]Great Lakes Water Quality Agreement Is Signed (Apr. 15, 1972)
[kw]Water Quality Agreement Is Signed, Great Lakes (Apr. 15, 1972)
Great Lakes Water Quality Agreement (1972)
Pollution;international agreements
[g]North America;Apr. 15, 1972: Great Lakes Water Quality Agreement Is Signed[00690]
[g]Canada;Apr. 15, 1972: Great Lakes Water Quality Agreement Is Signed[00690]
[c]Environmental issues;Apr. 15, 1972: Great Lakes Water Quality Agreement Is Signed[00690]
[c]Diplomacy and international relations;Apr. 15, 1972: Great Lakes Water Quality Agreement Is Signed[00690]
Britt, N. Wilson
Beeton, Alfred M.
Blaushild, David
Nixon, Richard M.
[p]Nixon, Richard M.;Great Lakes Water Quality Agreement
Trudeau, Pierre
[p]Trudeau, Pierre;Great Lakes Water Quality Agreement

The events that led to the signing of the GLWQA started with the white settlement of the shores of the Great Lakes. By 1972, the problems facing the lakes were numerous, varied, and severe. The eutrophication of Lake Erie was the most publicized problem, but the presence of exotic species upsetting the balance of fish populations, the incredibly high level of toxins such as dichloro-diphenyl-trichloroethane (DDT) DDT and polychlorinated biphenyls Polychlorinated biphenyls (PCBs), PCBs and the raw sewage and waste being dumped into the rivers that fed the lakes had been evident for years.

Almost two decades before the GLWQA was signed, scientists were encountering disturbing data. In 1953, N. Wilson Britt, while doing routine tests, found that the populations of mayfly larvae in lake sediment were down to almost zero in some areas, while populations of species adapted to oxygen-poor environments were high. Mayfly larvae have a relatively high oxygen demand, so declining numbers are taken as a warning sign of decreasing oxygen availability. About eight years later, Alfred M. Beeton published data that indicated that huge areas of central Lake Erie had no oxygen whatsoever. These data, combined with observations of sections of the lake that looked as though they were coated with green paint, led the popular press to broadcast the news of the “death” of Lake Erie.

Eutrophication Eutrophication is actually an overabundance of algae Algae in a lake. In a young lake, the supplies of nutrients, most typically phosphorous, are limited. There is more oxygen in young lakes, in part because the existing organisms are not numerous enough to deplete the oxygen supply. When human use of the land surrounding a body of water increases, phosphorous is often added to the lake in the forms of phosphate detergents and phosphorous-based agricultural fertilizers. When this happens, algae normally limited by lack of phosphorous grow furiously, using all of the available oxygen in the process. Other species can no longer survive. While large amounts of phosphorous were being dumped into all of the Great Lakes, Lake Erie reacted the fastest because of its small volume, only 109 cubic miles. Ontario, the next-largest lake, contains 405 cubic miles; and Superior, the largest, contains 2,933 cubic miles of water.

It was the eutrophication of Lake Erie that prompted David Blaushild of Cleveland to institute a “Save Lake Erie” campaign. “Save Lake Erie” campaign[Save Lake Erie] The thousands of signatures generated by this drive found their way to President Lyndon B. Johnson’s desk in the mid-1960’s, setting in motion the governmental machinations that would lead to the GLWQA in 1972.

The GLWQA was not solely concerned with eutrophication, although phosphorous dumping was one of the few disagreements between the nations involved. Canada’s Water Act called for a reduction of detergent phosphates to 5 percent, while the U.S. Clean Water Act Clean Water Act (1972) refused to set limits on detergents. Another great concern involved the levels of toxins found throughout the lakes. Mercury, DDT, PCBs, and other dangerous substances were found in quantities far exceeding the permissible levels for safe drinking water. In fish, many of these toxins bioaccumulate, so that concentrations in Great Lakes fish in the early 1970’s were found to be many thousands of times higher than those in fish caught elsewhere. The heavily industrialized shores of the lakes provide hundreds of point sources for chemical contaminants. The Cuyahoga River, which flows into Lake Erie at Cleveland, was so heavily contaminated that on June 22, 1969, it burst into flames. Several miles of the river that ran through the industrial section of the city caught fire as a result of the chemical waste the river contained. The public outcry following this event helped hasten the legislative efforts that ensued.

Indiana Dunes National Lakeshore on Lake Michigan, with a power plant in the background.

(National Park Service)

The amount of virtually raw sewage that was being dumped into all of the lakes was also disgustingly high. Major cities such as Buffalo and Detroit were pouring thousands of tons of nearly untreated sewage into the lakes every day. This contributed significantly to eutrophication trends, as well as to bacterial counts that rendered drinking water unsafe in many areas.

Another problem affecting the Great Lakes basin, along with most of Canada and the Eastern United States, was acid rain. The pH levels had been dropping slowly since the early 1960’s, and probably before, in the areas surrounding the lakes. This was most evident—and most critical—in the watershed areas just north of Lake Superior. The soils in this area are highly acidic to begin with, because of the vast expanses of evergreen forest, and do not have the buffering capacity that more basic soils have. The acidification of the rivers and streams feeding Lake Superior has severe implications for the fish supplies in the Great Lakes, because these rivers are major spawning grounds.

Acid rain Acid rain is caused, to a great extent, by nitrogen and sulfur oxides in industrial exhausts combining with water molecules in the air to form nitric and sulfuric acids. High-sulfur coal, commonly used to fuel the steel-smelting operations along the Great Lakes, is one of the worst offenders for the generation of these substances.

Thermal pollution was a less easily identifiable harm to the lakes. This pollution came from two major sources: the destruction of much of the forest around the lakes during the same time that a general climatic warming occurred, and industrial wastewater. Warmer water encourages algae growth, speeding eutrophication.

All of these factors combined to raise public concerns, which precipitated the signing of the GLWQA. The agreement itself was actually based on the Boundary Waters Treaty of 1909. Boundary Waters Treaty (1909) Since Lake Michigan is the only one of the five Great Lakes that is completely in the United States, it was not specifically included in the agreement. Earlier legislative efforts, such as the formation of the Great Lakes Fisheries Commission in 1955, were concerned with limited aspects of lakes conservation, but the GLWQA of 1972 was unprecedented in its vision and scope.


The GLWQA of 1972 addressed five main components (the five “freedoms”): freedom from toxins, freedom from accelerated eutrophication, freedom from floating materials such as oil and scum, freedom from substances producing “nuisance conditions” such as foul odors and unsightly colors, and freedom from sludge. The United States and Canada agreed to certain limits on pollutants, and set the date of December 31, 1975, as the point at which the programs proposed needed to be under way. The agreement also called for continuing adherence to the contingency plan for oil and hazardous-substance spills formulated in 1971.

The detailed document included specific stipulations on all of the concerns previously mentioned. Both countries agreed to the construction of waste treatment facilities consistent with the freedoms sought. They agreed to institute control requirements to eliminate mercury, various organic contaminants, radioactive waste, and other hazardous substances. They agreed to reduce the phosphorous input to Lakes Erie and Ontario, although the United States refused to set numbers for these limits. Limits on pesticides, sewer discharge, oil, and pollution from ships were established. The control of thermal discharges was instituted to minimize thermal pollution. Most important, the IJC, formed by the 1909 Boundary Waters Treaty, was assigned the task of undertaking a five-year study to assess progress.

By 1975, some things were improving. Lake Erie got through the summer without its annual algal bloom, beaches stayed open, and the lake looked like water again. Fish were back in the Detroit River. Phosphate content in the rivers that fed the lakes was down by at least 50 percent. DDT and mercury concentrations had dropped by 60 percent in some areas.

Not everything was perfect. Niagara Falls, New York, was still dumping almost raw sewage into the Niagara River. Some 39 percent of the population on the U.S. side of the lakes did not have adequate municipal sewage treatment, in contrast to 2 percent on the Canadian side. DDT had been banned altogether, but acid rain was still causing problems, although it was pointed out that in the Great Lakes themselves, the enormous volume of water and substantial buffering capacities would maintain the pH levels for some time. Nevertheless, some of the smaller lakes in Ontario and upstate New York were undergoing major changes attributable to this form of pollution.

In 1978, the IJC presented its findings from the five-year study mandated by the 1972 agreement. It was not as optimistic as the 1975 achievements would have led people to predict. Phosphorous loads exceeded the recommended target loads in all lakes. Lake Michigan was included in the study despite its exclusion from the GLWQA of 1972, because it was recognized that Lake Michigan’s water quality would directly affect that of Lake Huron. PCBs were still entering the lakes, mainly via the atmosphere. Mercury was still being found in fish, and lead was building up in the sediments at the bottom of the lakes. Pesticides, although on the decline, were still entering the waters in “substantial quantities.” Much of this came from nonpoint-source pollution, such as urban runoff and the atmosphere, making it extremely difficult to control.

The IJC report was taken seriously. The 1972 GLWQA was rewritten and greatly strengthened, becoming the International GLWQA of 1978. It added such concepts as limited-use zones, pretreatment of industrial waste, and, most important, effective enforcement programs. The new agreement provided the IJC with surveillance and monitoring authority in conjunction with federal, state, and provincial governments. The IJC was once again charged with keeping track of progress, with the help of the Great Lakes Water Quality Board and the Great Lakes Science Advisory Board. Under the 1978 agreement, the Great Lakes Water Quality Board developed the Great Lakes International Surveillance Plan in 1981 to coordinate monitoring activities.

In 1980, the IJC’s Science Advisory Board declared, contrary to the 1978 report, that acid rain was “perhaps the most serious environmental problem faced by the Great Lakes Basin.” It was recognized that, despite the buffering capacities of the lakes themselves, the acidification of feeder streams could cause considerable harm to the lake ecosystems. Furthermore, the atmosphere was depositing large amounts of many other toxins that were pouring out of smokestacks all over the country. The 1980’s saw a considerable amount of research and regulation in this area, but the problem is an ongoing one, and the ramifications of this type of pollution are uncertain.

Following the next report of the IJC, the Protocol of 1987 was added to the 1978 agreement on October 18, 1987. No new arrangements were included in this addition, but state and provincial governments were given increased recognition, and the protocol reiterated the two nations’ commitment to the preservation of the ecosystem. This commitment had been fortified a few years earlier, with the signing of the Great Lakes Charter in 1984. The charter set forth principles to maintain the integrity and protect the water resources of the Great Lakes.

The fight to restore and protect the Great Lakes is ongoing, and is expected to remain so for the foreseeable future. As long as humankind continues to use natural resources, normal ecological progressions will be inhibited and the balance will be upset. The Great Lakes Water Quality Agreement of 1972 was the first substantial governmental recognition of this fact. The agreement stands as a landmark in environmental history, not for its stringent limitations on pollution or for the programs it established, but because of its acknowledgment that the preservation of a shared environmental resource must take precedence over the interests of any single country. Great Lakes Water Quality Agreement (1972)
Pollution;international agreements

Further Reading

  • Ashworth, William. The Late, Great Lakes. New York: Alfred A. Knopf, 1986. An excellent proconservation history of the continuing degradation of the Great Lakes. Provides a well-written account of the use of the lakes. Weak on legislative efforts toward cleanup. Index and extensive bibliography.
  • Botts, Lee, and Paul R. Muldoon. Evolution of the Great Lakes Water Quality Agreement. East Lansing: Michigan State University Press, 2005. Documents the historical binational effort to protect the Great Lakes. Accessible to students and professionals.
  • Caldwell, Lynton Keith, ed. Perspectives on Ecosystem Management for the Great Lakes: A Reader. Albany: State University of New York Press, 1988. Collection of papers from a U.S.-Canadian interuniversity seminar presents discussion of topics ranging from history to ecology to law. Chapter by Leonard B. Dworsky, “The Great Lakes: 1955-1985,” is especially informative concerning the GLWQA. Each chapter has its own bibliography.
  • International Reference Group on Great Lakes Pollution from Land Use Activities. Environmental Management Strategy for the Great Lakes System. Windsor, Ont.: International Joint Commission, 1978. Report from the five-year study on which the 1978 GLWQA was based is comprehensive and readable. Includes glossary and bibliography.
  • Kuchenberg, Tom, Jim Legault, and Mary Ellen Sisulak. Reflections in a Tarnished Mirror: The Use and Abuse of the Great Lakes. Sturgeon Bay, Wis.: Golden Glow, 1978. Small volume of photographs and text focuses primarily on pollution’s effects on the fishing industry. Provides interesting histories of each lake plus two sections that summarize the various forms of pollution and what must be done to control them. Includes interviews with researchers and government officials involved (or not) in the restoration efforts.
  • McGucken, William. Lake Erie Rehabilitated: Controlling Cultural Eutrophication, 1960’s-1990’s. Akron, Ohio: University of Akron Press, 2000. Documents the thirty-year rehabilitation of the lake after public awareness and government regulation helped pressure the detergent industry to produce alternative detergents.
  • Powers, Charles F., and Andrew Robertson. “The Aging Great Lakes.” Scientific American, November, 1966, 95-104. An early perspective on the pollution problems in the lakes, when the public outrage was heating up. Good basic diagrams of watershed areas, lake succession, and fish species.
  • Rousmaniere, John, ed. The Enduring Great Lakes: A Natural History Book. New York: W. W. Norton, 1979. Collection of eleven short articles compiled by the American Museum of Natural History provides a good overview of the problems facing the lakes, combined with photographs documenting various positive and negative aspects of the region. Short bibliography.
  • “Signing of Great Lakes Water Quality Agreement, April 15.” Department of State Bulletin, May 8, 1972, 652-657. Provides the texts of Nixon’s and Trudeau’s remarks on the occasion.

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