Sustaining Our Water Resources (1993)

Edith Brown Weiss

Georgetown University Law Center

Washington, D.C.

In June 1992, 178 countries met in Rio at the United Nations Conference on Environment and Development to finalize a global strategy for sustainable development¹ that merges environmental conservation with economic development (UNCED, 1992). Sustainable development is inherently intergenerational because it implies that we must use our environment in a way that is compatible with maintaining it for future generations. This intergenerational perspective constrains our management of the environment and its resources, including water.

Water resources are critical to both economic development and the maintenance of natural systems. While water technically does not disappear but only changes form, the quality and quantity of water resources in any one place can be degraded or improved by a variety of human activities. Every generation must therefore be concerned about the supply and quality of water, particularly fresh water, and about who has access to it and at what cost.

We celebrate today the tenth anniversary of the Water Science and Technology Board (WSTB). This is the time frame of half a generation. In reviewing the activities of the board, it is appropriate to put them into the generational time frame and look at their contribution to the goal of achieving intergenerational fairness in the development and use of water resources. In

this context it is particularly important that the board has initiated collaborative studies with other countries, for the problem is a global one.

At the WSTB symposium, "Managing Water Resources in the West Under Conditions of Climate Uncertainty", in 1990, I presented a theory of intergenerational equity and its application to water resources. It may be useful here to convey the essence of the theory before examining how the activities of the board during the past 10 years have implicitly advanced intergenerational equity and suggesting how intergenerational concerns can be incorporated in future board activities.

The theory posits that there are two essential relationships—to the natural system and to other generations of the human species. With regard to the first, we are part of the natural system; we are affected by it and our actions affect it. As the most sentient of species, we have a special responsibility to care for the system.

The second relationship is distinctly intergenerational. As members of the human species, we hold the natural environment of our planet in common with all members of our species: past, present, and future generations. As members of the present generation, we hold the earth in trust for future generations and have rights as beneficiaries of the trust to use and benefit from the environment. Past, present, and future generations are partners with each other in the care and use of the planet. Moreover, all generations have an equal normative claim in relation to the natural system of which they are a part. There is no basis for favoring one generation over another in the care and use of the planet.

The concept of intergenerational fairness in using and conserving the planet strikes deep chords in the major cultural and legal traditions of the world, including the Judeo-Christian, Islamic, African customary law, and Asian nontheistic traditions. The notion of equality among generations has deep roots in public international law, as illustrated in the Preamble to the Universal Declaration of Human Rights, the United Nations Charter, the International Covenant on Civil and Political Rights, and other documents (Weiss, 1989).

The intergenerational framework also has an intragenerational dimension. Were it otherwise, members of the present generation could allocate the benefits of the world's resources to some communities and the burdens of caring for it to others and still claim on balance to have satisfied intergenerational fairness. Moreover, poverty today is a primary cause of ecological degradation, which means that maintaining the robustness and integrity of the planet for future generations requires attention to the demands for intragenerational equity today.

When future generations become living generations, they will have certain rights to use the natural system for their welfare and certain obligations to care for it, which they can enforce against one another. These derive from the position of each generation as a member of the partnership of generations across time. In many instances, intergenerational and intragenerational actions are consistent. But in other instances, such as the withdrawal of ground water in excess of recharge rates to supply potable drinking water to poor communities or the rapid withdrawal of water from nonrechargeable aquifers, there will be conflicts between immediate satisfaction of needs and long-term maintenance of the resource. In these cases, means need to be developed to reconcile intergenerational concerns with the demands of the living generation.

Weiss (1989) has proposed three principles of intergenerational fairness conservation of options, quality, and access. These are briefly set forth below. The WSTB has gone far toward advancing these principles of intergenerational equity in that it has gathered knowledge essential for assessing intergenerational risks and effects.

The first principle—options—requires each generation to conserve the diversity of the natural (and cultural) resources base, so that it does not unduly restrict the options available to future generations in solving their problems and satisfying their own values. Conversely, each generation is entitled to diversity comparable to that enjoyed by previous generations. Fulfilling this principle can be accomplished not only by conserving resources but also by developing new technologies that create substitutes for existing resources or that exploit and use resources more efficiently. In some instances, maintaining the quality of the resource means enhancing the diversity of the resource base, as in the case of rivers or lakes with rich fisheries or wetlands with their species diversity.

Several WSTB studies have been inherently concerned with this issue. Foremost is that on restoring aquatic ecosystems, including wetlands, rivers, streams, and lakes, once they have been degraded, so that they can be useful to present and future generations. Other studies include those on water transfers as a means to meet the increasing demands for water in the West, on managing water resources under conditions of climate uncertainty, on the operations of the Glen Canyon Dam on the Colorado River, on recharge of ground water aquifers, and on management of the Mexico City aquifer.

The second principle of intergenerational equity is the conservation of quality, which requires that each generation maintain the quality of the planet so that on balance it is passed on in no worse condition than when received and gives each generation a right to planetary quality comparable to that enjoyed by previous generations. While the principles of diversity and quality are connected, they must be treated separately. The analogy is to a trust in which the investments may all be of high quality but not diverse or, conversely, they may be diverse but not of high quality. Both scenarios adversely affect the robustness of the trust.

Many of the WSTB's studies have been concerned with gathering information needed to maintain the quality of water resources. The studies have notably focused on the national irrigation water quality program, contamination of ground water, alternatives for cleaning up ground water, use of ground water models in the regulatory process, managing wastewater in urban coastal areas and the effectiveness of the Great Lakes Water Quality Agreement.

The third principle of intergenerational equity is that each generation should provide its members with equitable rights of access to the legacy of past generations and should conserve this access for future generations. This may be translated, for example, into a right to potable water supplies. The WSTB's studies on providing adequate water supplies of acceptable quality to developing countries advance this principle. These include the studies on the ground water aquifer in Mexico City as a source of drinking water and on soil and water research needed to sustain agriculture in developing countries. The principle of access also means that the present generation must incorporate the full cost of supplying water, not only of delivery and treatment costs, to ensure that the real price of water resources to future generations is not significantly higher than to the present generation. The study of water transfers in the West addresses this issue.

The two binational studies conducted by the WSTB, one with Canada on the Great Lakes Water Quality Agreement and the other with Mexico on the limitations of Mexico City's ground water aquifer as a source of drinking water, both address important intergenerational issues.

In a 1985 WSTB report published by the NRC and the Royal Society of Canada, the committee reviewing the Great Lakes Water Quality Agreement addresses intergenerational equity explicitly in Chapter 7. The study points out that toxic contamination of the lakes represents one of the greatest immediate threats to the interests of future generations because the time necessary to remove them from the lakes through natural processes is very long, especially for Lakes Michigan and Superior. While deterioration in water quality can sometimes be reversed through removal of hazardous

contaminants from lake bottoms, rivers and landfills, the costs of doing so may be enormous. In some cases the water quality may become so degraded that future generations will have less flexibility in using it for contact recreation, fishing, and municipal water supplies. The committee recommended that the interests of future generations "be considered more explicitly in the Agreement" and recommended ways to accomplish this (U.S. National Research Council and Royal Society of Canada, 1985).

In its ongoing study of the Mexico City aquifer, another NRC committee is addressing the sustainable use of the aquifer, which is inherently an intergenerational problem. On the one hand, there is a need to supply water for a growing urban population, but there are obstacles to fulfilling this need, such as continued pumping in excess of recharge rates, location of urban settlements over recharge areas, and institutional barriers. On the other hand, there is a problem of water quality in that various pollution sources are contaminating the aquifer. The latter raises the question of how to allocate the costs of preventing and cleaning up water pollution not only across the various strata of society but also across generations. The Mexico aquifer study is also intergenerational in the sense that it addresses the rights of future generations to a potable water supply. It would be useful if the study could address ways in which the interests of future generations in a sustainable supply of fresh water could be integrated into administrative decision making and even into the marketplace.

The principles of intergenerational equity form the basis of intergenerational rights and obligations, which are held by each generation. They derive from the temporal position of each generation in relation to other generations. They are complemented by intragenerational rights and obligations among members of the present generation, which derive from the intergenerational ones. These intergenerational rights are to receive the planet in no worse condition than did the previous generation, to inherit comparable diversity in the natural and cultural resource bases, and to have equitable access to use and benefit from the environmental system. Future generations thus have rights to maintenance of the robustness and integrity of the natural system.

The rights of future generations regarding diversity and quality of freshwater resources represent in the first instance a moral protection of interests, which must be transformed into legal rights and obligations. They are generational rights that exist regardless of the number and identity of the

individuals making up each generation, and they can be evaluated by objective criteria and indices applied to the environment from one generation to the next.

Developments outside the environmental area make acceptance of intergenerational rights in the environmental system a natural and desirable evolution. International human rights laws, such as the prohibitions against genocide and racial discrimination, are directed toward protecting future generations as well as the present generation. Eliminating an entire people is legally more odious than murdering an equal number of people who constitute a minority of several groups. Similarly, discrimination denies an "equal place at the starting gate" not only to the present generation of the suppressed group but also by implication to future generations (Weiss, 1990).

The existence of intergenerational rights has significant implications for policy. For example, it may affect population policies, since rapid population increases will affect the demand for resources and strain environmental quality. However, whether a generation chooses to meets its obligations and guarantee the rights of future generations by constraining exploitation, consumption, and waste or by constraining population growth is a decision each generation must make (Weiss, 1993). The rights of future generations mean that the present generation cannot ignore this choice.

Similarly, the decisions we make today about our water resources should be scrutinized from the point of view of their impact on future generations. Scientific knowledge about water systems, identification of the opportunities and limits of technological advances, and understanding of the socioeconomic context in which water resources are used are essential to ensuring fair use for future generations. The WSTB's studies provide a knowledge base, which needs to be extended, for intergenerational scrutiny of decisions affecting water resources.

Intergenerational rights also have significant implications for the marketplace and for the international competitiveness of countries. Future generations are not represented in the marketplace today; they must be. If we develop a market for water, it is important that the rights of future generations to a stable water supply of acceptable quality be incorporated into the market price of water. This requires, first, that we understand the fundamental entitlement among generations. Under the proposed theory, future generations have an equal claim with the present generation to use and benefit from the natural environment. With this as the premise, the task is to develop the appropriate mix of economic instruments to ensure effective representation of future generations (Weiss, 1993). The WSTB studies that look at the use of contingent valuation and extreme values in the context of managing the Glen Canyon Dam and the proposed work on the valuation of ground water

offer an opportunity to address the incorporation of intergenerational interests in the marketplace.

Incorporating intergenerational interests is difficult, since the major environmental instruments that we use today start from the point of view of the present generation. The instrument of "externalities" to account for the effects of pollution, such as water pollution, starts from the viewpoint of the present generation. The discount rate, which is the primary tool for considering long-term effects, is ineffective in considering costs and benefits more than a decade or two away (Norgaard, 1991; Rothenberg, 1993). Moreover, with water resources, there are already a number of intentional distortions in the market that are unrelated to generational or environmental concerns. These include the large subsidies to agricultural water and the treatment of water as a resource that has no market price.

Unless we are willing to address the intergenerational dimension of resource use, we will also be unwitting partners in reducing our competitiveness as a country. To the extent that future generations, saddled with much higher levels of debt, have to pay more in real terms for the resources and services they receive today, they will have fewer resources to devote to maintaining options and conserving quality (Kotlikoff, 1992). This in turn will reduce their ability to be innovative in responding to new developments in the market or to new environmental problems.

The challenge before us is to ensure that the interests of future generations in our planet, and our water resources in particular, are represented in the decisions we make today. The work of the Water Science and Technology Board is an invaluable source of scientific knowledge and understanding about how to achieve intergenerational fairness in using and conserving our water resources.

Kotlikoff, L. J. 1992. Generational Accounting—Knowing Who Pays, and When, for What We Spend. Free Press, MacMillan, Inc., New York. 261 pp.

Norgaard, R. 1991. Sustainability as Intergenerational Equity: The Challenge to Economic Thought and Practice. World Bank Report No. IDP 97. The World Bank, Washington, D.C.

Rothenberg, J. 1993. Economics of Intertemporal and Intergenerational Equity. In N. Choucri, ed., Global Environmental Accord: Environmental Challenges and International Responses. MIT Press, Cambridge.

United Nations Conference on Environment and Development (UNCED). 1992. Agenda 21 and the Rio Declaration on Environment and Development. Adopted June 14, 1992.

U.S. National Research Council and Royal Society of Canada. 1985. The Great Lakes Water Quality Agreement: An Evolving Instrument for Ecosystem Management. National Academy Press, Washington, D.C.

Weiss, E.B. 1989. In Fairness to Future Generations: International Law, Common Patrimony, and Intergenerational Equity. Transnational and United Nations University, New York and Tokyo.

Weiss, E. B. 1990. Our Rights and Obligations to Future Generations for the Environment. American Journal of International Law 84:1.

Weiss, E. B. 1993. Intergenerational Equity: Toward an International Legal Framework . Global Environmental Accord: Environmental Challenges and International Responses. MIT Press, Cambridge.

World Commission on Environment and Development (WCED). 1987. Our Common Future. Oxford Press, Oxford, England.