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2
Sharing Water Resources with Future Generations

Edith Brown Weiss

Associate General Counsel for International Activities*

U.S. Environmental Protection Agency

Washington, D.C.

The human species has been on this planet only a short time. At least in the western world, we have become accustomed to progress and we expect it. However, because of the grave global environmental problems confronting them, many people today are questioning whether progress will always continue. The subject of this symposium—water resources and climate change—presents this challenge directly. Progress cannot continue if resources essential to our existence are seriously affected by changes in the global climate. This threat raises the issue of what we can do, and what we have an obligation to do, to conserve essential resources, such as fresh water, so that they are available in the quality and quantities needed at a cost that is acceptable.

The threat of climate change raises an important new dimension to the area of water resources: the issue of intergenerational equity. It would be possible to approach this topic by examining the intergenerational implications of either climate change or management of water resources. This presentation focuses on water resources as an intergenerational equity issue, with climate change and the scientific uncertainties regarding it as aspects of the problem.1

I will present a theory of intergenerational equity that relates the present generation to past and future generations and relates the human species to the natural system of which we are a part;

*  

On leave from position as professor of law, Georgetown University Law Center. The views expressed in this article are solely those of the author and do not necessarily represent the views of the U.S. Environmental Protection Agency.



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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona 2 Sharing Water Resources with Future Generations Edith Brown Weiss Associate General Counsel for International Activities* U.S. Environmental Protection Agency Washington, D.C. The human species has been on this planet only a short time. At least in the western world, we have become accustomed to progress and we expect it. However, because of the grave global environmental problems confronting them, many people today are questioning whether progress will always continue. The subject of this symposium—water resources and climate change—presents this challenge directly. Progress cannot continue if resources essential to our existence are seriously affected by changes in the global climate. This threat raises the issue of what we can do, and what we have an obligation to do, to conserve essential resources, such as fresh water, so that they are available in the quality and quantities needed at a cost that is acceptable. The threat of climate change raises an important new dimension to the area of water resources: the issue of intergenerational equity. It would be possible to approach this topic by examining the intergenerational implications of either climate change or management of water resources. This presentation focuses on water resources as an intergenerational equity issue, with climate change and the scientific uncertainties regarding it as aspects of the problem.1 I will present a theory of intergenerational equity that relates the present generation to past and future generations and relates the human species to the natural system of which we are a part; *   On leave from position as professor of law, Georgetown University Law Center. The views expressed in this article are solely those of the author and do not necessarily represent the views of the U.S. Environmental Protection Agency.

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona with this theory, we can look at issues of intergenerational equity raised by the way we use and care for our planet (Brown Weiss, 1989). I will then apply this theory to questions of water resources, examining future generations' rights to these resources and analyzing possible management strategies in the intergenerational context. RELATING THE RIGHTS AND OBLIGATIONS OF THE PRESENT GENERATION TO OTHER GENERATIONS AND TO THE NATURAL SYSTEM The relationship of our generation to other generations in the context of our natural system has two aspects. One is our relationship to other members of the human species—to the human community extended over time. The second is our relationship to the natural system of which we are a part. We should view both relationships in the context of a trust, in which the present generation is simultaneously a beneficiary and a trustee. Each generation is a beneficiary in its use of the planet for its own welfare and well-being and, at the same time, a trustee for conserving the planet for future generations. Similarly, as the most sentient of creatures in the natural system, we are at the same time a part of the system, entitled to use it and benefit from it, and a trustee for its conservation. There are several models available for analyzing the relationship between our generation and future generations. Two prominent, opposing models are the ''preservation'' and "opulent consumption" models. The preservation model demands that everything be preserved as it is; the present generation, according to this view, has no right to change anything. This model is reflected in the English "natural flow" theory of water and in preservationist legislation regarding wilderness and other untouched areas. While the model may be appropriate for certain unique natural resources, it is not generally consistent with economic development and improved standards of living. The opulent consumption model encourages immediate consumption of resources, either because there may not be another tomorrow or because the higher level of consumption will make possible greater wealth for this and future generations. This model also has serious limitations; it does not recognize the need to use the environment on a sustainable basis, nor does it consider appropriate environmental costs in its economic calculations.

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona An alternative approach is to view the human community as a partnership extended over time, in which each generation is a partner. Describing such a theory, Edmund Burke observed that "as the ends of such a partnership cannot be obtained in many generations, it becomes a partnership not only between those who are living but between those who are living, those who are dead, and those who are yet born." The purpose of the partnership is to realize and protect the welfare and well-being of every generation. This requires sustaining the life support systems, ecological processes, environmental conditions, and cultural resources that are necessary for our survival and well-being and for the robustness of the natural system of which we are a part. The question, then, is how to determine what constitutes "fairness" between generations. As John Rawls (1971) has suggested, we could attempt to imagine what environmental ethic we would espouse as members of a generation if we did not know where along the spectrum of time we are living—whether we are near the first or last generation. In such a position, what would we regard as a fair use of the planet? Presumably, we would want to leave the environment at a minimum no worse off than we found it. That does not mean that we should not use the resources at our disposal to improve our own well-being, or to improve the quality of the environment. It is inevitable that we will change the environment as we use it, but on balance we should leave the planet no worse off than we found it. This raises the question of the responsibility of the present generation for correcting the environmental abuses of past generations. If a river or lake that may be important to future generations is polluted due to actions taken 50 years ago, can the present generation simply leave it polluted? Surely not. The present generation has some obligation to participate in the removal of that pollution; however, the costs could be distributed over several generations through revenue bonds or other financing mechanisms. The requirement that each generation must leave the environment no worse off than it found it implies that there is a minimum level of robustness in the natural system that must be passed on to future generations. This minimum floor of robustness is deeply rooted in international law as reflected in the United Nations Charter, the Universal Declaration of Human Rights, and many other documents. Intergenerational equity, as I have been describing the term, requires an intragenerational dimension. If each community or each country had a completely parochial attitude, caring only

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona about potential impacts on its own citizens and their descendants, it would still be necessary to ensure that other countries adopted policies that take intergenerational rights into account. To care about our own descendants or our own nationals means we have to care about the environment in which they exist for the long term. If we care about that environment in the long term, we have to care about what happens today in the conservation of the environment—including what happens in other communities and countries—because we alone cannot insure a decent environment for our descendants. The actions of other communities and countries may have a profound effect on the future environment of our community and country. That means we have to care about whether other people are willing and able to fulfill their intragenerational obligations. PRINCIPLES OF INTERGENERATIONAL EQUITY What are principles of intergenerational equity that we can derive from the intergenerational ethic described above? Four criteria may be helpful in deriving such principles. First, such principles should permit present generations to use resources today, but not at great expense to future generations. Nor should present generations be required to sacrifice greatly for the benefit of future generations. Second, the principles should be reasonably clear in application. Third, the principles should not require that we predict the values of future generations. Fourth, to the extent that such principles apply internationally, they must be consistent with the values and cultural traditions of the different countries of the world. Application of these criteria gives rise to a set of three principles, which I have labeled "conservation of options," "conservation of quality," and ''conservation of access." "Conservation of options" can be defined as the obligation to maintain the diversity of the resource base. This does not necessarily imply maximizing diversity. For example, while a monoculture is vulnerable to climatic change, maximizing diversity can lead to dynamic instability in an ecosystem. The conservation of options principle requires preservation of the components of diversity that provide maximum robustness to the system. "Conservation of quality" is the obligation to preserve the quality of the environment. This is not a principle against change in the environment, but some balance must be achieved in doing so. Environmental degradation in one area must be balanced by im-

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona provements in another. This requires the development of a framework within which that balancing act can occur. Changes in use may make pristine water less clean, but other changes may make polluted water cleaner; as long as there is no unbalanced degradation of quality, overall conservation is met. Finally, "conservation of access" can be defined as the right of a beneficiary to use a resource. It is essentially a nondiscriminatory, equitable right. Future generations should not be required to pay an extraordinarily high price for an essential resource because the present generation refused to put a price on the resource, deferring the cost of its depletion to future generations. AN INTERGENERATIONAL APPROACH TO WATER RESOURCE PROBLEMS Using the three principles of intergenerational equity to look at water resource problems can help us better understand our generation's rights and obligations. In turn, this thinking should suggest appropriate management strategies that could be translated into concrete actions that will benefit future generations. Water Resource Problems with Intergenerational Impacts Several problems can exist between our generation and future generations in the use of water resources, some of which may be exacerbated by changing climate and by the scientific uncertainty regarding changing conditions. Perhaps the most obvious example of an intergenerational water resources problem is toxic contamination of surface and ground waters. Most toxic contamination can be removed, but the flushing times in lakes, such as Lake Superior, may be decades, or even a century, and the costs of removing contamination, as in ground water, may be so high that the contamination is essentially irreversible. With ground water, the high costs of cleaning up or containing toxic contamination are becoming increasingly well understood. Another intergenerational water problem is saline pollution of fresh water. For example, the pumping of ground water aquifers at rates sufficient to cause saltwater intrusion into the aquifer is hard to reverse at acceptable costs; consequently, it may lead to the abandonment of the ground water aquifer. Rising sea levels,

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona which could result from global climate change, could cause marine water to intrude upon freshwater streams. Some downstream countries may lose that fresh water altogether, because attempting to change the institutional arrangements for allocating those rivers may cause serious conflicts. Degradation of water resources can have several effects. First, it can damage the ecosystem, which is difficult to reverse. It also can limit the uses of the waters. For example, pollution in the Great Lakes contaminates fisheries and makes the lakes unsuitable for swimming and other forms of recreation. So the resource may exist, but the uses that make the resource desirable to present and future generations may be diminished. Similarly, degradation of the quality of forests may diminish the environmental services they perform in maintaining watersheds. Depletion of resources, particularly freshwater resources in specific areas, is another intergenerational problem. Depleting resources before their value has been recognized creates higher real prices for future generations. For example, natural gas was burned off of natural helium-bearing deposits before it was recognized as valuable. In terms of freshwater resources, two problems come immediately to mind. One is the problem of pumping ground water faster than the recharge rate, which depletes not only the ground water but also surface water (because of the hydrological links between ground and surface water) and could leave once fertile agricultural areas barren and cause settlements to move. Second is the depletion of nonrechargeable aquifers. This is occurring in the United States, northern Africa, and other parts of the world. In this country, we do not generally put a price on water as a resource; we charge only for transporting it and turning it into a commodity that is usable by communities. This increases the rate at which the resource is depleted. Alternative sources of water are theoretically available, but they may not be readily available and certainly are not available at acceptable costs. Thus, depletion of aquifers raises the real price of water for future generations. A final intergenerational water problem is restricted access to freshwater resources. For example, changes in global climate may cause areas dependent on the availability of a certain level of fresh water to become warmer and drier. This would raise difficult questions concerning large-scale diversions from water-rich areas such as North America, China, and the Soviet Union, which are expected to have more water. Climate change could also increase pollution concentrations and reduce the amount of water available for fishing and other recreational uses. Further, it could affect

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona downstream communities by creating saltwater intrusion upstream because of insufficient water to hold the saltwater back. Applying Intergenerational Principles to Water Resource Problems The water resource problems discussed here raise serious questions of intergenerational equity. The principles defined earlier in this paper provide an approach for analyzing these problems and finding solutions that strike a proper balance between our generation's rights and our obligation to future generations. Application of the first principle, conservation of options, could mean maintaining a diversity of fresh water supplies—both ground water, surface water, and the technology for turning salt water into useable water. It could mean a moratorium on the mining of aquifers. It could mean tighter restrictions on the depletion of nonrechargeable aquifers. It could also require reexamining our system of subsidizing water for agriculture (which also receives other price supports) in order to make it profitable. If the second principle, conservation of quality, is taken seriously, it could require further action to prevent irreversible, or effectively irreversible, toxic contamination of water. The principle could require actions to prevent saline intrusion from rising sea levels. It could mean planning the locations of dams by considering projected sea level rises to ensure that downstream waters do not become subject to saline intrusion. Finally, the third principle, conservation of access, could require the present generation to incorporate the full cost of supplying water, not just the cost of delivery and treatment, so that the real price of the water resources is not significantly higher to future generations than it is to the present generation. INTERGENERATIONAL RIGHTS AND OBLIGATIONS The principles of intergenerational equity translate into a set of intergenerational rights and obligations. In this context, obligations and rights are linked together. John Austin (1873), the English legal theorist, said that there may be groups of obligations that exist independently of any correlative rights. Here, however, I believe that rights are correlated with obligations, and the content

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona of the rights is derived from the principles of intergenerational equity set forth above. Specifically, future generations have rights related to the maintenance of the natural system. (Without such rights, future generations would be subject to Parfit's famous paradox: "Rights are individual rights but until people are born they do not exist and so therefore they cannot have rights.") The existence of these generational rights does not depend upon knowing either the number or kind of individuals who will be present in the future. Rather, we can define rights using objective criteria, flowing from our understanding of the natural system and our responsibility to maintain the robustness of that natural system. How could such rights be enforced? In part, they could be factored into the decision-making process. It would be possible to have a representative of future generations, similar to a guardian ad litem , who could participate in administrative or judicial procedures. But, it is particularly important to consider how one could incorporate the interest of future generations into the marketplace. They are not represented in the marketplace now; the discount rate does not sufficiently represent their interests. Thus, as we think about marketing water rights, we must also consider how the interests of future generations can be represented in this market. STRATEGIES FOR INCORPORATING INTERGENERATIONAL INTERESTS INTO DECISIONS AFFECTING WATER RESOURCES There are many strategies for incorporating intergenerational equity into water resource decisions. First, as noted above, we need to give representation to the interests of future generations: in the marketplace, in political and administrative decisionmaking, and perhaps in judicial bodies. For certain venues, this representation might take the form of an "ombudsman" or "watchdog" for future generations. Such an ombudsman could not only enforce laws relevant to future generations, but could also warn of dangers to the ecosystem, respond to complaints about damage to water resources, and mobilize support for conserving water resources. Second, we need to have a good monitoring system. Without monitoring, there is no way to judge this or any generation's stewardship of resources. The United States has taken many steps

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona to improve its ability to monitor surface and ground water, but more can still be done. Moreover, monitoring needs to extend to other parts of the world. We also need to be able to monitor social rates of adaptation to changes in water supplies. Third, we need to think of scientific and technological research as a component of intergenerational equity. Research that would not be supported in the private sector but that is important to maintaining the quality and accessibility of water resources for future generations should be supported. For example, research to promote understanding of the fate and transport of pollutants in ground water, or research to facilitate efficient development and use of alternative water resources (such as research into desalination technologies) should be viewed as part of an intergenerational strategy. If nonrechargeable aquifers are depleted, there may be an obligation to engage in research aimed at making more efficient use of water supplies and making alternative supplies available at equitable prices. Fourth, we need to focus on assessing the long-term impacts of our water use, particularly in light of the scientific uncertainty regarding changing climate conditions. There should be a process that takes into account the possible impacts of proposed actions on future generations—essentially starting from their interests and working backwards. This process could be incorporated in a "long-term conservation assessment" or as part of an environmental impact assessment. Fifth, we have to revise how we think about the question of maintenance. Maintenance is now a stepchild to capital investments, but it should be recognized as an intergenerational equity issue. One can understand this issue best by considering capital investments, such as municipal sewage treatment plants, that may be used briefly and not maintained. Failure to maintain such facilities expends resources for our own marginal benefit at the expense of future generations. Recognizing the importance of maintenance to future generations means that the ease and cost of maintenance must be explicit criteria in project design and development. Moreover, it means that facilities that use water resources and infrastructure that transports water should be kept in good repair so that water resources are not unnecessarily wasted. For example, ditches with 70 percent loss rates, like some in the West, may not be a proper way to transport water from an intergenerational perspective. Sixth, the intergenerational approach suggests that we need emergency assistance arrangements in place in case of hazardous

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona substance spills into water bodies. Our own Clean Water Act, which requires immediate notification of any discharge of oil or hazardous substances, is a useful precedent.2 Laws in other countries are not always as good; in some cases, it is not the legal provision that is inadequate but its implementation. Even when there is an international agreement with emergency response provisions, responses to a major accident can be too slow. For example, after the Sandos chemical factory spill, it took more than 24 hours for any notice to be given to countries downstream from the plant, even though notification provisions were part of the international agreement covering the Rhine River.3 Seventh, the intergenerational approach suggests the need for certain changes to legal arrangements governing water resources. For example, if potential climate change causes people to consider large-scale diversions, it will be essential to develop acceptable criteria for evaluating such diversions—for examining the benefits to the recipient communities, the future needs of the area of origin, the effects on the welfare of present and future generations in both areas, the impacts on the ecosystem, the long-term water loss during transport, alternative sources of water in each area, and the significant effects on weather and climate. The National Water Commission in 1973 devised economic criteria for interbasin transfers that we might update in light of our concern with global climate change and our intergenerational concerns (National Water Commission, 1973). A number of legal changes suggested by the intergenerational approach arise in the context of managing ground water aquifers. First, we need to protect the recharge areas of ground water aquifers. Within the United States, this means increased attention to land-use planning. Land use thus acquires an important intergenerational dimension. Moreover, in some areas we may need to manage ground water aquifers so that withdrawals do not exceed recharge rates. This requires greater understanding of the recharge rates and the development of monitoring equipment. To prevent the rapid loss of ground water aquifers and ensure that future generations do not have to pay substantially higher prices for ground water, we must develop a system that effectively narrows the existing price differential between ground water and other water supplies. In some cases, it will be necessary to develop guidelines and/or agreements to control the mining of ground water in interstate and/or international aquifers. For this purpose, the work that has been done at the University of New Mexico on an agreement for international ground water management is relevant (Rodgers and Utton, 1985).

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona We also need to quantify water rights, particularly instream flow rights, from an intergenerational perspective. Potentially, the ecosystem could be further damaged under changing climate conditions if the instream flow rights are not quantified and prioritized. The intergenerational approach also requires moving beyond legal impediments to economically efficient water uses. This may be done, for example, by redefining beneficial use and by increasing the marketing of water rights, while ensuring that the interests of future generations are represented in the marketplace. Finally, an intergenerational approach may require institutional changes to respond to advances in our scientific understanding of climate change and of the likely socioeconomic effects of such change. Mechanisms for anticipating and responding efficiently to these changes are needed. In international agreements, flexibility to respond to change often takes the form of protocols or annexes to the agreements that can be easily updated at regular meetings of the parties. The Montreal Protocol on Substances that Deplete the Ozone Layer,4 for example, permits parties to accelerate the reduction or phase-out of a listed substance without formally amending the protocol. Issues involving scientific uncertainty can also be handled through scientific advisory councils and regular scientific assessments, the results of which may be transmitted to the parties for consideration in their periodic meetings. The Great Lakes Water Quality Agreement of 1978 incorporates several of these mechanisms.5 Nationally and locally, the important intergenerational issue is how to handle scientific uncertainty with respect to the effects of climate change. For example, in the western United States, possible changes in climate raise important water problems. One problem is how to make water rights flexible in the face of uncertainty over climate change. There are several ways to accomplish this, including leasing or marketing water rights and use of the public trust doctrine. Another problem is how to make water management schemes sufficiently flexible to adapt to climate changes and to protect the interests of future generations. Our management strategy for dams and reservoirs is fairly flexible for short-term management of peak flows and droughts; in the long term, however, these systems may be inadequate, and we must consider seriously how to increase their flexibility. Finally, to return to the intergenerational perspective, to the extent that current use of water resources imposes disproportionate burdens on future generations, how should we compensate them? Is the greater income that we are generating through our use of

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona water resources sufficient compensation? Should we focus on research and development or provision of facilities to assist in future adaptation to changes in the location, form, and quality of water resources? Or, as I have suggested in a different context, should we consider trust funds for future generations? Throughout history the human species has been both clever and very lucky in using its natural resources. As resources have become scarce and the prices have risen, uses have become more efficient or substitutes have been discovered or invented that could serve the same function—often better or more economically than the previous resource. Fresh water, however, is different. Our actions now have long-term effects on the quality of fresh water and the access that people will have to fresh water. Technology will help some people in the future, for example, by providing affordable, large-scale desalination plants for marine water, but there are no substitutes for fresh water. If we are not careful today, we can leave our children a huge bill for cleaning up rivers and lakes that we have polluted. We can leave our great-grand-children a nearly irreversible legacy of eroded watersheds, polluted ground water, and contaminated lake and rivers bottoms. Water is vital. Simple fairness demands that we conserve it for future generations and that we find ways to consider the interests of future generations in the decisions that we make today. NOTES 1.   Approaching the topic from the perspective of climate change would raise a number of additional issues. A definition of intergenerational equity in terms of changing climate might be a rate of climate change sufficiently slow to permit adaptation without excessive costs. This would require knowing the rate at which the physical system and the natural system can adapt. Rates of social adaptation will differ depending on the location, the economic and social conditions, and the country's technological capacity. We understand very little about social rates of adaptation. Even if we understood them better, it would be necessary to select some country's adaptation rate as the norm. Should it be the rate of those least able to adapt or should it be a more moderate rate with assistance provided to those who adapt more slowly? 2.   Federal Water Pollution Act, as amended by the Clean Water Act of 1977, 33 U.S.C.A. Sec. 1321(b)(5).

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Managing Water Resources in the West Under Conditions of Climate Uncertainty: Proceedings of a Colloquium November 14–16, 1990 Scottsdale, Arizona 3.   Convention on the Protection of the Rhine Against Chemical Pollution. Art. 11, 16 International Legal Materials 242 (1977). 4.   Protocol on Substances That Deplete the Ozone Layer. 26 International Legal Materials 1550 (1987). 5.   Great Lakes Water Quality Agreement, Nov. 22, 1978. U.S.-Canada, 30 U.S.T. 1383, T.I.A.S. 9257 (1978). REFERENCES Austin, J. 1873. Austin's Jurisprudence, Lectures on Jurisprudence. London: J. Murray. Brown Weiss, E. 1989. In Fairness to Future Generations: International Law, Common Patrimony, and Intergenerational Equity. Dobbs Ferry, NY: Transnational Publishers and United Nations University. Burke, E. 1903-1911. Reflections on the revolution in France. In works of Edmund Burke . London: Bell. National Water Commission. 1973. New Dimensions in U.S. Water Policy. Washington, D.C.: Government Printing Office. Rawls, J. 1971. A Theory of Justice. Cambridge, Mass.: Belknap Press. Rodgers, A., and A. Utton. 1985. The Ixtapa draft agreement relating to the use of transboundary groundwaters. Natural Resources Journal 25:713.