Vol. 39 Articles Editor
Mexico City is sinking. So concludes a New York Times article detailing the implications of climate change for Mexico City. But the article also notes the most severe and immediate consequence of climate change for cities all over the world: the effect on fresh water resources. In many places, climate change will cause longer and more frequent droughts, while increased heat will cause an increase in evaporation of groundwater and a decrease in river-feeding snowpack. Critically, these effects will vary place-to-place, so changes will occur in not only water quantity but also water distribution. The result is that the world is about to see a massive shift in water-wealth and -poverty that will have drastic and potentially devastating effects on freshwater resources around the globe.
As the climate changes, cities and countries across a wide swath of the globe will struggle for increasingly scarce freshwater resources. This struggle will manifest in escalating international competition for transboundary water resources, those shared by more than one country. At present, these resources are governed by a patchwork of more than 3,600 agreements and state practices, including multiple multilateral agreements; bilateral and regional agreements governing individual bodies of water; and customary international law. But as countries that are used to getting their water from rainfall see extended droughts, and rivers that used to supply multiple countries with plenty see reduced flow, “the human-built infrastructure for managing water will become obsolete.” The international legal regime for freshwater resources will need to adapt to keep up with the changes and prevent conflict over scarce resources.
The current legal order is embodied by two overarching principles, enshrined in the 1997 United Nations Convention on Non-Navigational Uses of International Watercourses: “equitable and reasonable use” and “the obligation not to cause significant harm” to neighbors. Theoretically, these are flexible enough to accommodate climate change. But implementation is left up to individual countries, and “neither [principle] seeks to allocate the benefits of and responsibilities for a transboundary fresh water resource” under the stress of climate change. They cannot guard against a “tragedy of the commons,” where no country has an incentive to responsibly husband shared and diminishing water resources. They can also only be fairly applied after a violation has occurred, so they cannot prevent potentially irreversible unfair uses. What happens when simply satisfying one country’s need for water drains a resource on which multiple countries have historically relied?
There are two primary challenges regarding the adaptability of current international water law. The first is that the vast majority of today’s water management laws and systems are stationary, allocating specific water resources based on “the idea that natural systems fluctuate within an unchanging envelope of variability.” But climate change will create a state of near-permanent instability, both between and within regions. Such treaties will be unable to keep up with changing water resources and will either cease to function or will themselves generate conflict as they become increasingly ill-adapted to the present state of the resource. The second concern is that in many places, particularly developing countries, international water management is ineffective. This ineffectiveness can stem from treaties that are too vague and have no enforcement mechanisms, or from the unwillingness or inability of participating states to apply treaties they have joined. For obvious reasons, an ineffective treaty will do nothing to mitigate the dangers of climate change.
The Indus River Basin, governed primarily by the 1960 Indus Waters Treaty between India and Pakistan, is an example of a water management system unlikely to withstand climate change, with potentially dire consequences. The treaty allots three tributaries to Pakistan and mandates that India ensure that a minimum quantity of water flow through them. It has survived three wars and provided effective dispute resolution through arbitration tribunals and the International Criminal Court. However, the Indus relies heavily on glaciers and could drop to 20% below 2000 levels by 2060. As flow lessens, people on both sides who already believe that they are entitled to larger shares of the river will become louder. India will be less and less willing to provide the required quantity of water to Pakistan; Pakistan’s farmers, who depend almost exclusively on the Indus, will go thirsty. China and Afghanistan, which are not parties to the Treaty but which are upriver of both India and Pakistan, may seek larger shares of the river as well, further limiting the water available. India and Pakistan are both nuclear powers with significant historical enmity; neither the Treaty nor their relationship empowers cooperative responses to lower flow, and so conflict could escalate very quickly.
Other water systems have demonstrated a more promising approach. After the dissolution of the former Yugoslavia, the Sava River Basin in its midst became a transboundary river. To manage it, the neighboring countries agreed to the Framework Agreement on the Sava River Basin, overseen by a representative Sava Commission. As a part of the Framework Agreement, the Commission implements the Protocol on Flood Protection, which “acknowledged the likely consequences of climate change on the water regime in the Sava River Basin and the need for effective adaptation measures. By signing the Protocol, the countries in the basin agreed to cooperate on flood risk management by taking into account the impacts of climate change.” The Commission has begun a pilot project to evaluate the prospective effects of climate change on the Basin in preparation for a trans-basin flood management plan.
“[T]he effectiveness and flexibility of institutional arrangements to adapt to change will arguably determine whether a basin falls into conflict or rises to cooperation in times of water stress.” The difficulty, of course, is how to establish a legal order that will be both flexible enough to handle instability and effective enough to prevent conflict. Numerous scholars have suggested ways that domestic regimes might adapt, but there are “major psychological, political, institutional and legal barriers to using the law to distribute the extreme risks of global climate change.” Furthermore, many of the suggested adaptations rely on a significantly stronger rule of law than exists on the international level. Strengthening the international rule of law, for example through a “Climate Change Security Council” to address all climate change issues, would make adaptation easier, but this seems extremely unlikely in practice, especially given the rising global antipathy to international governance.
Instead, the most promising avenue is a cooperative basin-based approach like that of the Sava River, in which the countries that share a given resource create a joint resource-management institution empowered to collect data and allocate resources accordingly, and with sufficient funding and authority to be effective. Unfortunately, such an institution requires acceptance by all relevant nations of its necessity, and the ability and willingness to prioritize it. Throughout much of the world this acceptance is not forthcoming, particularly in areas where the countries surrounding a basin have contentious relationships.
Throughout human history, control over freshwater resources has been one of the primary causes of war. The current international legal regime was designed to prevent such conflicts by assuring that each country uses transboundary waters in a responsible way that respects the rights of other countries. But as the climate changes and the global freshwater needs and supply change, these existing regimes will prove inadequate. If the international community cannot develop an equitable way to adapt existing international law to a new, and changing, paradigm, the world is likely to see a dramatic increase in violent conflict.
 Michael Kimmelman, Mexico City, Parched and Sinking, Faces a Water Crisis, N.Y. Times (Feb. 17, 2017), https://www.nytimes.com/interactive/2017/02/17/world/americas/mexico-city-sinking.html?_r=1.
 See, e.g., Glen Hearns and Richard Kyle Paisley, Lawyers Write Treaties, Engineers Build Dikes, Gods of Weather Ignore Both: Making Transboundary Waters Agreements Relevant, Flexible, and Resilient in a Time of Global Climate Change, 6 Golden Gate U. Envtl. L.J. 259, 265-66; Christina Leb, International Water Law and Climate Change: Avoiding Disputes Over Water, Off. of Sci. and Tech. Austria, Bridges vol. 18 (2008), http://ostaustria.org/index.php?option=com_content&view=article&id=3231&Itemid=1006.
 See P.C.D. Milly et al., Stationarity Is Dead: Whither Water Management?, 319 Science 573, 573 (2008).
 U.N. Dep’t of Econ. and Soc. Affairs, Water for Life Decade: Transboundary Waters, http://www.un.org/waterforlifedecade/transboundary_waters.shtml (last visited Mar. 5, 2017); see also International Freshwater Treaties Database, Or. State Univ., www.transboundarywaters.orst.edu/database/interfreshtreatdata.html (last visited Mar. 5, 2017).
 Joseph W. Dellapenna, Global Climate Disruption and Water Law Reform, 15 Widener L. Rev. 409, 411.
 Joseph W. Dellapenna, The Sources of the International Law Applicable to Water Resources, 3 Waters and Water Rights § 49.04 (Amy K. Kelley ed., 3rd ed. 2017).
 Gabriel Eckstein, Water Scarcity, Conflict, and Security in a Climate Change World: Challenges and Opportunities for International Law and Policy, 27 Wis. Int’l L.J. 409, 435.
 Milly et al., supra note 3.
 See Eckstein, supra note 7.
 Nidhi Jamwal, In the Din over the Indus Waters Treaty, the Climate Change Factor Has Been Overlooked, Scroll.in, https://scroll.in/article/817910/in-the-din-over-the-indus-waters-treaty-the-climate-change-factor-has-been-overlooked (Nov. 26, 2016).
 Dhanasree Jayaram, Why India and Pakistan Need to Review the Indus Waters Treaty, Climate Diplomacy, https://www.climate-diplomacy.org/news/why-india-and-pakistan-need-review-indus-waters-treaty (Aug. 2, 2016).
 Dhanasree Jayaram, Water Sharing Between India and Pakistan: An Opportunity for Cooperation, Am. Security Project, http://www.americansecurityproject.org/water-sharing-between-india-and-pakistan-an-opportunity-for-cooperation (Apr. 15, 2013).
 U.N. Econ. Comm’n for Eur. Int’l Network of Basin Orgs., Water and Climate Change Adaptation in Transboundary Basins: Lessons Learned and Good Practices 23-24 (2015), available at http://www.unece.org:8080/index.php?id=39417&L=0.
 Hearns & Paisley, supra note 2, at 269.
 See, e.g., Robin Kundis Craig, “Stationarity Is Dead” – Long Live Transformation: Five Principles for Climate Change Adaptation Law, 34 Harv. Envtl. L. Rev. 9; A. Dan Tarlock, How Well Can Water Law Adapt to the Potential Stresses of Global Climate Change?, in Northwestern Law Colloquium Series – Environmental Law 1-2 (2012), available at www.law.northwestern.edu/colloquium/environmental/documents/Spring2012_Tarlock.pdf.
 Tarlock, supra note 15, at 12.
 Trina Ng, Safeguarding Peace and Security in Our Warming World: A Role for the Security Council, 15 J. Conflict & Security L. 275 (2010).
 See Eckstein, supra note 7, at 447.
 For example, the Kura-Aras River Basin in the South Caucasus, shared by Georgia, Turkey, Armenia, Azerbaijan, and Iran, has not been cooperatively managed since the fall of the USSR, and prospects look grim due to the lack of diplomatic relations between Armenia and Azerbaijan. See Ryan B. Stoa, Shared Waters of the South Caucasus: Lessons for Treaty Formation and Development, in Sustainability of Integrated Water Resources Management 335 (Shimelis Gebriye Setegn & Maria Concepcion Donoso eds., 2015).
 Ng, supra note 17.