Can the world learn to live with less water?


This is part of a series of interviews by Bloomberg Opinion columnists on how to solve the world’s most pressing political challenges. It has been edited for length and clarity.

Sarah Green Carmichael: The 2022 drought continues to affect global shipping, food production, hydropower and nuclear generation. Diminishing snow accumulations mean that water scarcity is expected to continue as global warming intensifies. You hold the Charles Dyer Norton Professor of Land and Urban Planning at the Harvard Graduate School of Design and previously led the International Development Group in the Department of Urban Studies and Planning at MIT. Some of your previous work has focused on urban transportation, violence, political leadership, and housing. How did you become interested in water?

Diane Davis, Professor of Land and Urban Planning, Harvard Graduate School of Design: Almost every major city sits on a body of water, whether it’s a river, lake, or of the ocean. And this is a global problem: there is either too much water or not enough water; there is water in places where it is not supposed to be, and water not in places where it is supposed to be. It is one of the biggest problems on the planet.

SGC: There is currently a traffic jam on the Mississippi River created by low water levels, which we have also seen recently on the Danube and the Rhine. What can be done to keep these rivers navigable?

DD: The thing about rivers is that you can’t solve the problem on site; the problem needs to be addressed along the entire length of this watercourse. And that usually means – especially in the European context – that you not only have different provinces or states, but also different countries. How to create a regional decision-making body that is transnational but smaller than the EU? This is the question for planners and decision makers.

One of the things we need to think about is whether we need new political powers to govern water. Water does not follow these political boundaries. Look at the Colorado River Valley. Each of these different states has different policies on who controls the water, who decides whether the water is for agricultural or urban uses, and these issues are then debated in their legislatures. And of course, the private sector is involved here too. I see water as a governance issue and not just as climate change.

SGC: There’s also a lot more at stake than shipping. Farmers rely on this water to produce food; for example, millions of people in the Horn of Africa are suffering from hunger due to drought. Many countries depend on dams for hydroelectricity. And in France, the cooling of river water is necessary for nuclear power plants.

DD: We need a broader mission of protecting natural resources that have been important for urbanization, modernization and economic growth. We must also integrate our reflection on the origin of energy [with other priorities]. Should we use rivers for energy, or should we use something else for energy because we need rivers for other things — for transportation, for food? Urbanization has grown national economies for so long, but we don’t think enough about getting back to a more sustainable way of building cities.

SGC: You mentioned earlier that part of the problem is that there is too much water in some areas and not enough in others. This may be a naive question, but is there a realistic way to move water from areas that have too much to areas that have too little? I imagine something like a Roman viaduct.

DD: Expensive and massive infrastructure would be required, which could include canals or an extensive drainage system or underground pipes. Viaducts also work, as in your mention of the Roman period. There’s a lot of ingenuity in engineering, but getting water from one place to another involves questions of sovereignty, about who owns the water in the first place. In some countries – in Mexico, for example – groundwater belongs to the nation, but the states have jurisdiction over the rivers. Moreover, in a federal system like that of the United States, it would be difficult to build new water infrastructure that carries water from one state to another, unless there is regional coordination or a national mandate.

There are some interesting examples of cross-border water agreements – many in the Middle East, including between Turkey and Syria a few decades ago and between Israel and Jordan more recently – which have facilitated the construction of infrastructure that bring water from elsewhere, including countries with access to ocean waters that could be purified and transported inland. I hope for more innovation on this front. But the political challenges are as delicate as the technical challenges.

SGC: What about our own responsibilities as individuals? Every summer in Massachusetts, where we live, municipalities ban the use of city water on lawns – yet every summer I walk past large homes with lush lawns with signs that say “Well Water used”. And I’m like, “Wait, isn’t that coming from the same aquifer?” Do we need more public awareness campaigns to help us save water?

DD: There have been. In the ’80s in California, I remember they told us, like, we shouldn’t flush the toilet [as often]. So historically campaigns have been used at the state level. But now in Massachusetts, we keep hearing about this record-breaking drought, but I haven’t seen any public messaging campaign. In the United States, it has to start locally, because no one wants the federal government to tell them what to do.

SGC: What about other ways to get people to save water?

DD: Water costs money, so there is always the market solution to take care of it. But does that mean people who can afford it will water their flowers, while low-income people can’t afford to pay the tariff? Attempts to conserve water raise a host of equity issues – not just for rich and poor, but also for cities and countryside.

There are developers who buy land in Southern California just for the water rights. They don’t even plan to grow things on the land. They just have access to water. This can have a distorting effect on real estate markets. We’re going to have to think more about the metrics you use to rate a property based on whether or not it has water. In Mexico, for example, you can’t get a permit to build a house unless you can prove you have access to water.

How do we encourage sustainable actions without impinging on market dynamics in a way that will create political backsliding? That’s the big question.

SGC: Are there any other places where you have seen competition for water between different groups?

DD: I worked on a project with a team of landscape architects and lawyers to address a problem of groundwater depletion outside of Mexico City. We looked at the struggles between Corona Brewery, which is owned by InBev, and local farmers. These farmers grow barley for brewing, but they need water to grow the barley; manufacturers need water to process beer.

My role within this team was to think about proposing an alternative regional coordination mechanism built around this set of connected aquifers. In Mexico and many places, decisions about water use permits are made by the municipality. But the municipality is smaller than the aquifer. And in fact, in this area, there were five different municipalities around the aquifer. The challenge therefore is to work with the political institutions of the 19th century – municipalities, states, federal territories – in the 21st century.

SGC: And in terms of governance, are there any governance solutions you’ve seen work or would like to see more of?

DD: I would like to see experiments. Are there any informal models or pilot projects that bring communities that share an aquifer together to test the waters – sorry for the metaphor – to make decisions about basic resources like water?

The other thing is, [water scarcity] could speed up or slow down depending on what happens with climate change. Maybe we will have a lot of rain, then a few years of drought. We therefore need governance mechanisms that are not frozen in time.

SGC: What about technological solutions?

DD: There are water treatment and purification technologies [more efficiently]. There are nature-based solutions, like replanting different things in these areas that allow for greater water conservation. We can also look at indigenous communities and [traditional] farmers and reintegrate some of their traditions into conservation thinking. And there are also innovations in the world of architecture concerning the capture of water, the recovery of rainwater.

They are micro-solutions to a larger problem. They could be part of the solution in combination with innovation, building redesigns and public policy – ​​from local campaigns to larger changes in public policy. We just have to start moving forward in every way possible.

More from Bloomberg Opinion:

• San Francisco’s empty train cars create problems for public transport: Justin Fox

• Italian winemakers and grapes adapt to climate change: Frank Wilkinson

• The global energy order is rapidly collapsing: Liam Denning

This column does not necessarily reflect the opinion of the Editorial Board or of Bloomberg LP and its owners.

Sarah Green Carmichael is editor-in-chief of Bloomberg Opinion. Previously, she was Ideas and Commentary Editor at Barron’s and Managing Editor of Harvard Business Review, where she hosted “HBR IdeaCast.”

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