As Greece emerges from a decade-long financial crisis, the city of Athens is grappling with major challenges: E.U.-imposed austerity measures, a real estate collapse, ongoing security and migration issues, climate change, and now COVID-19. Kostas Bakoyannis, 41, was elected mayor in 2019, promising stability and reinvention. The son of two prominent Greek politicians, Bakoyannis is the city’s youngest elected chief executive but has had considerable experience. Holding undergraduate and graduate degrees from Brown University, Harvard University, and the University of Oxford, he was governor of Central Greece, mayor of Karpenissi, and served at the Greek Ministry of Foreign Affairs, the European Parliament, and the World Bank. He also holds positions with the Hellenic Agency for Local Development and Local Government, European Council on Foreign Relations, and United Nations Sustainable Development Solutions Network. On a recent visit to Cambridge, he spent time with Lincoln Institute Senior Fellow Anthony Flint.

Anthony Flint: You have said that you are focused not on grand projects, but on day-to-day quality of life in a city trying to make a comeback in a more incremental fashion. What are your reflections on your successful campaign and the experience thus far of being at the helm of local government?

Kostas Bakoyannis: I think in any campaign, it’s always about the message and not the messenger. Elections in the past in Greece have been about candidates higher up, talking down to the people. I took a different approach and started walking out in the neighborhoods. I listened with care and found that the people want a city to build its self-confidence and be optimistic again. Now we are reinventing city services and reinventing the city. Athens has three records: the least urban green per capita in Europe, the most asphalt, and our houses have the most square meters. We want to reclaim public space and especially reclaim space from the automobile. We have been studying traffic circulation, and are planning to close parts of the city center to cars. We will also create an archeological walkway around the city.

All in all, I’m living my dream. I’m giving it my all. I’ve been in local government for 10 years; higher office doesn’t compare. One day, when I first began my journey in local government, I was depressed and thinking we are a failure, and then I walked out and saw a playground we had just opened. It’s not about resolving the conflict between North and South Korea. It’s real, tangible, incremental change, improving the quality of life.

AF: Athens has been vexed over the years by the problem of vacant buildings and storefronts, graffiti, homelessness, and a general image of being dark and dirty. Can you tell us about your plans to clean things up?

KB: There was a very good article in an international magazine about the Greek economy, but at the top there was a photo of Athens, with two homeless people sleeping in front of closed stores that were full of graffiti. This is our challenge. Don’t forget that we are in a global race to attract talent, technology, and investment. And Athens is changing day by day. To mention a few examples: We have adopted the “broken windows” theory of social behavior [which suggests that visible signs of crime and decay invite more of the same] and are coordinating with the police. We have special equipment and run campaigns to clean up graffiti. We have a program called Adopt Your City, and public-private partnerships that are already bearing fruit. We are asking people who care and love the city to come help us. Regarding drugs, reforms have been made. The parliament recently passed a measure on supervised spaces for drug use—we haven’t operated one yet, but we are preparing to make it mobile, so it doesn’t stay too long in any one neighborhood. Local government will be able to operate such spaces. We are reclaiming public space, like Omonia Square, a city landmark—I think that’s going to be a symbol. There are elevated expectations about public space . . . it’s not just public works. We are producing more of a product, an experience.

AF: As part of that effort, you attracted controversy for clearing out squatters in the neighborhood of Exarchia, an effort that included dawn raids and relocating refugees and undocumented immigrants. How do you fulfill your campaign promise to restore law and order and curtail illegal immigration, while still being sensitive to the human lives at stake?

KB: Here is an example: An individual calling himself Fidel was running a hostel in a school, occupying it, and charging money. We securely moved the children to take advantage of social service provisions. Greek media have a thing about Exarchia. It becomes a political weapon for one side or the other. I don’t look at it that way. We have 129 neighborhoods, and Exarchia is a neighborhood with its own issues. Much of what we do has to do with persisting and insisting—it’s a question of who will get tired first. We will not get tired first.

On the subject of pluralism, we’re the canary in the coal mine. We survived the economic crisis, and we’re stronger today than in the past 10 years. We have more depth to our democracy, stronger institutions. We isolated extremists. We confronted the Fascist Nazi party Golden Dawn—we went to neighborhoods where they were doing well. We didn’t wag our fingers and tell people they were bad for voting for Golden Dawn. We said: we can provide better solutions to the problems you face.

Athens is a Greek city, a capital city, and a center for Greeks around the world. Having said that, Athens is changing and evolving. I remember seeing a young woman who was black in a parade, and she was proudly holding the flag—I think what she was saying was, ‘I’m as Greek as you are.’ We want to make sure everyone living in the city has the same rights and obligations.

AF: What are the most important elements of your plans to help Athens combat climate change—and prepare for its inevitable impacts in the years ahead?

KB: Think different! It is all about working bottom up. What’s happening that is most interesting in terms of public policy is in the cities, which are true laboratories of innovation. Nation-states are failing—there’s so much partisanship, and a toxic environment, and bureaucracies that cannot handle real problems; cities are closer to the citizen. We are proud to be a part of C40. Athens has developed a policy for sustainability and resilience. Among other things, we are working on ambitious but realistic interventions to liberate public space, multiplying green space, and creating car-free zones. For us, climate change is not a theory or an abstraction. It is a real and present danger that we can’t just sweep under the rug. It demands concrete responses.

AF: You recently had the opportunity to return to Cambridge and Harvard. What level of interest did you find in the future of Athens? Are there things you have learned from American cities, and what can the United States learn from you?

KB: I was enthused and heartened by the level of interest and am thankful for the engagement. I must admit that I was very proud to represent a city with a long and glorious past and a promising, bright future. We may live on different sides of the Atlantic, and in very different cities, but it is interesting that we face similar challenges as urban centers evolve and are transformed. And it is always great to share experiences and learning moments. Policies to further resilience are the most obvious example. And of course, battling social inequalities is at the top of all of our agendas. I am glad to have begun promising and fruitful conversations which will continue in the months and years to come.

Photograph: Athens Mayor Kostas Bakoyannis. Credit: City of Athens.

Underlying the urgent need for sustainable, high-quality urbanization in China—a new approach taking hold after decades of unchecked growth—is the question of money. Public funds can supply only a small amount of the total investment needed to build low-carbon infrastructure in cities across the country. In the specific areas of energy conservation and environmental protection, some estimates state public funds will cover less than 25 percent of costs (Bond Magazine 2018). For Chinese cities, this means mobilizing private capital is imperative. A growing interest in green bonds—bonds specifically intended to fund projects related to sustainability—suggests this financing tool could be a viable option.

The World Bank issued the first official green bonds in 2009. In the 10 years following, cumulative global green bond issuance exceeded $521 billion. As of 2018, green bonds account for about one percent of the global market (Tay 2019). China has rapidly become the world’s second largest green bond market since releasing national green finance guidelines in 2016; the total amount of money raised through state-issued Chinese green bonds—not all of which align with international definitions and standards—was about $31 billion in 2018 (Meng et al. 2018) and hit almost $22 billion in the first half of 2019 (Meng, Shangguan, and Shang 2019). 

Generally speaking, the projects that benefit most from green bond proceeds are large, have long investment horizons, and rely on proven technology—metro lines and other clean transportation are good examples. Green bond proceeds can be allocated to existing assets, such as a solar energy plant operating in a city, or to upcoming capital investment.

In June 2019, the Ganjiang New Area in Jiangxi Province issued the first municipal bond in China bearing a “green” label (China Securities Network 2019). The bond followed the regulations of the People’s Bank of China, the country’s central bank, and was issued to finance smart utility pipelines. The issuance was 12 times oversubscribed, indicating that investors in China are willing to finance projects tied to sustainable infrastructure and industry (Ibid). 

Farther south, in Shenzhen, two unlabeled green bonds helped finance an International Low Carbon City (ILCC) project launched in 2012. The ILCC is a flagship demonstration project of the China-E.U. Partnership on Sustainable Urbanization. When completed, it will cover more than 53 km2 and display an array of green buildings and low-carbon technologies (Zhan, de Jong, and de Brujin 2018).

Cities like Shenzhen, which have a relatively large GDP and municipal budget, can afford to experiment with innovative financing methods in order to circumvent financial barriers and constraints. Many cities still rely on sales of land as the main municipal finance resource for capital investment. This is a serious problem for smaller cities in particular, because the value and amount of their land and level of private sector interest in the land are all lower than in larger cities. Oftentimes, smaller local governments will have to settle for selling land to a nonideal or polluting industry, such as a steel company. Chinese cities hoping to reduce carbon footprints could look to aspects of Shenzhen’s financing efforts to diversify funding away from land sales. 

This alternative was further validated in November 2018 when a local finance vehicle in Wuhan issued offshore green bonds and raised $400 million (Davis 2018). The bond proceeds will go toward expanding sustainable public transportation (Moody’s Investors Service 2018).

Municipal officials can increase the efficacy and feasibility of green bonds by providing incentives such as interest rate subsidies, bundling different environmental assets (such as solar, water, and pollution cleanup investments) into larger bonds to attract big investors, and attaching measurable indicators to create accountability and transparency (IISD 2018). Monitoring, reporting, and verification is also a key part of green bonds.

As a debt instrument that can harness private capital for climate-oriented projects, green bonds appear naturally suited to the needs of cash-strapped cities in China that are trying to achieve low-carbon transition. Green bonds will almost certainly play a larger role in the Chinese and global financial sector going forward.

Excerpted and adapted from “Green Bond Financing and China’s Low-Carbon City Development” by Carl Hooks. Master’s thesis, Peking University, 2019.

Photograph: Green bonds helped finance construction of the International Low-Carbon City demonstration site in Shenzhen. Credit: Paulson Institute.

References

Bond Magazine. 2018. “王琰: 关于我国发展绿色市政债券的探讨” [Exploring the development of green municipal bonds in China]. 中央财经大学绿色金融国际研究院 [International Institute of Green Finance of the Central University of Finance and Economics] (blog). October 24. https://mp.weixin.qq.com/s/z9-3ndosGAIwxSmNNYFDOQ.

China Securities Network. 2019. “江西赣江新区发行全国首单绿色市政专项债” [Jiangxi Ganjiang New Area issues country’s first municipal green bond]. 新浪财经 [Sina Finance], June 21. http://finance.sina.com.cn/stock/relnews/hk/2019-06-21/doc-ihytcerk8306348.shtml.

Davis, Morgan. 2018. “Wuhan Metro Seals Landmark Green Deal for LGFVs.” Global Capital Asia, November 29. https://www.globalcapital.com/article/b1c12qj1rmd7p2/wuhan-metro-seals-landmark-green-deal-for-lgfvs.

IISD (International Institute for Sustainable Development). 2018. “How to Issue a Green Bond in China: A Step-by-Step Guide.” London: Climate Bonds Initiative. https://www.climatebonds.net/files/files/How-to%20GreenBonds%20China.pdf.

Meng, Alan Xiangrui, Monica Filkova, Ivy Lau, Sherry Shangguan, Jin Shang, and Xiaopeng Chen. 2019. “China Green Bond Market 2018.” London: Climate Bonds Initiative; Beijing: China Central Depository & Clearing Company (February). https://www.climatebonds.net/resources/reports/china-green-bond-market-2018.

Meng, Alan Xiangrui, Sherry Shangguan, and Jin Shang. 2019. “China Green Bond Market Newsletter H1 2019 / 中国绿色债券市场季报 2019 上半年度.” [In English and Chinese.] London: Climate Bonds Initiative; Beijing: China Central Depository & Clearing Company (July 31). https://www.climatebonds.net/resources/reports/china-green-bond-market-newsletter-h1-2019.

Moody’s Investors Service. 2018. “Moody’s Assigns Green Bond Assessment (GBA) of GB1 to Wuhan Metro’s Proposed Green Senior Perpetual Securities.” November 20. https://www.moodys.com/research/Moodys-assigns-Green-Bond-Assessment-GBA-of-GB1-to-Wuhan–PR_391149.

Tay, Shirley. 2019. “Investors Are Pouring into Green Bonds. That May Not Be for the Best.” CNBC, January 29. https://www.cnbc.com/2019/01/30/investors-are-pouring-into-green-bonds-that-may-not-be-for-the-best.html.

Zhan Changjie, Martin de Jong, and Hans de Brujin. 2018. “Funding Sustainable Cities: A Comparative Study of Sino-Singapore Tianjin Eco-City and Shenzhen International Low-Carbon City.” Sustainability 10, no. 4256 (November 17, 2018): 1–15.

At the heart of Shenzhen, China, the city’s massive, wavelike Civic Center stands surrounded by a mind-boggling panoply of futuristic skyscrapers. Forty years ago, this area was home to just a few scattered fishing villages on the Pearl River Delta. Today, approximately 24 million people live within Shenzhen’s greater urban area.

In China, Shenzhen has come to stand for something much bigger than itself. On a hill downtown, a statue of revered former Chinese leader Deng Xiaoping striding purposefully toward the Civic Center helps explain why. Deng took control of China in 1978, after the death of Mao Zedong. The transition marked an end to decades of isolation from the outside world that had been dominated by command-and-control planning. Deng turned the country in a radically new direction, launching the Reform and Opening program to loosen the strictures that had bound the country for so long. And Shenzhen led the way into the future.

Deng granted the newly created city a license to operate as an economic superlaboratory, a place to explore the promise of the free-market economy. It was a sink-or-swim proposition, and in the years since, Shenzhen has succeeded wildly. Yet Shenzhen’s spectacular growth has come at a cost. As the area transcended its naturally marshy environment and turned from literal backwater into economic powerhouse, much of its land cover succumbed to blacktop and concrete. During storms, the abundance of paved-over land caused widespread flooding, as well as large-scale releases of urban pollution into nearby Shenzhen Bay and the Pearl River Delta.

Shenzhen is hardly alone in facing these problems. But continuing in its role as a national hotspot of innovation, it has become a unique laboratory for thinking about how to build livable cities throughout China and beyond.

Six miles northeast of Deng’s statue, Professor Huapeng Qin stands on a rooftop, surrounded by sensors measuring wind speed, temperature, and evaporation. He is looking for solutions.

Based at the local satellite campus of Peking University, Qin is at the forefront of an effort to turn Shenzhen into a “sponge city.” Using techniques that mimic nature, sponge cities can catch, clean, and store rain, which reduces the risk of flooding and keeps local drainage and water treatment systems from being overwhelmed.

Although it takes its cue from centuries-old thinking, the modern concept of the sponge city began forming in Europe, Australia, and the United States in the early to mid-1990s. The movement was a reaction to two common phenomena in urban development. First, just as happened in Shenzhen, most rapidly developing cities pave over huge amounts of land, eliminating a significant amount of natural forest cover, filling in lakes and wetlands, and severely disrupting the natural water cycle. Second, the traditional approach to urban stormwater management has focused on moving as much rain as possible off the land as quickly as possible, not capturing it for reuse.

Sponge city thinking marks a significant shift away from traditional “gray infrastructure”—think concrete pipes and dams—to “green,” or natural, infrastructure such as rain gardens and forests. The sponge city approach aims to restore some of those natural functions by allowing urban areas to transform the menace of stormwater into a boon: extra water for dry times.

Sponge city techniques therefore have multiple benefits. They can help soften the impact of flooding, improve both water quality and water supply, and help fix environmental problems. The sponge city concept is a relatively new arrival in China, but it has gained traction here fast. That’s partly due to the country’s tremendous growth over the past several decades, which has drastically altered the landscape. It’s also due to a new mindset about the risks of pursuing prosperity at all costs. In July 2012, a huge rainstorm in Beijing led to flooding that caused 79 deaths and an estimated $1.7 billion in damage. The incident galvanized national leaders.

In late 2013, President Xi Jinping officially endorsed the sponge city concept, and the following year the Ministry of Housing and Urban-Rural Development issued a set of technical guidelines aimed at ensuring that 70 percent of surface runoff be captured in place. The central government also launched what would ultimately become a 30-city pilot program to prove out the concept. Shenzhen is one of the pilot cities, and it’s no coincidence that the sponge city concept has gotten more traction here than anywhere else in China. From financial policy to the tech sector, “Shenzhen has always been very willing to borrow ideas from outside China and try them out,” says Qin. The sponge city idea is no different. “First it was just scattered pilot projects, but now the concept is being incorporated into Shenzhen’s master plan.”

In this case, Qin and his students are trying to learn more about techniques for creating green roofs, using plants grown in a medium of lightweight engineered soil to catch rain where it falls, slowly meting it out afterward. Such techniques are “very similar to natural systems,” Qin says. “Natural systems look very simple, but the processes are very complex. So we’re trying to understand those processes.”

A sponge city has several interchangeable building blocks. At a large scale, protecting or restoring forests and natural ground cover helps give water a chance to sink in. At smaller scales, there are several options. Permeable pavement can be used on roadways, sidewalks, and pathways to allow water to infiltrate the ground, rather than wash off into the local stormwater system. Retention ponds and constructed wetlands help catch and filter water, allowing it to slowly percolate into the local water table. So-called rain gardens perform a similar function at a smaller scale, and can easily be incorporated into neighborhood green space or even homes. Green roofs catch and filter rain, along the way watering plants that, Qin says, can help reduce surface temperature by up to nine degrees Celsius.

Shenzhen’s embrace of the sponge city concept has been driven by its spirit of innovation, but also by the fact that the effects of an unbalanced water cycle are often plain to see here. Heavy rains can overwhelm local water treatment plants, sending nutrient-laden wastewater directly into Shenzhen Bay and the Pearl River Delta, causing large algae blooms. People are also worried about the impacts of climate change. In what may have been a taste of what’s to come, Super Typhoon Mangkhut, which hit in 2018, blew down half the trees in the city.

Qin says computer models predict that with climate change, total annual rainfall will be comparable with current levels, but that precipitation will be much “flashier”: extreme events like short-duration, high-intensity rainstorms will become more common. This area has absorbed an influx of millions of people over the past few decades, largely by turning its back on the water that was once its defining characteristic. Now, Qin and others across the city are committed to finding new ways forward. The lessons they are learning and applying here are the first steps in what may soon be a sweeping transformation—not only in the city around them, but also throughout China.

“Sponge cities are just one example of how China is taking up the sustainability agenda,” says Zhi Liu, director of the Peking University-Lincoln Institute Center for Urban Development and Land Policy. Acknowledging the urgency of building climate resilience in the face of extreme weather and other challenges, he says, “This is not something China wants to do in order to look good. It comes out of necessity.”

Until two years ago, the 105-acre patch of green space now known as Honey Lake Park was an abandoned agricultural experiment station. The dominant features of the park, which sits not far from downtown Shenzhen, were a neglected grove of lychee trees and two fish ponds. Today, walking into the park feels like walking into an architectural rendering. Yet in the company of an expert, it quickly becomes clear that the park is not only aesthetically pleasing but also eminently functional.

Yaqi Shi, a technical director with the Shenzhen-based Techand Ecology & Environment company, helped design the park. The paths that we are walking on, she explains, are constructed of permeable pavement, and the park’s rolling contours are hugged by small swales that help slow and catch runoff. A series of ponds in the middle of the park is sown with native rushes that Techand raised in its own nursery. Signs throughout the park point out the various sponge city elements and explain how they work.

Shi, whose professional focus is ecological restoration, speaks with the brisk economy of an engineer. But the delight in her voice is evident when she speaks of the evolution of this project. “The park turned out to have a really user-friendly feeling,” she says. As we walk, Shi points out a library, a children’s play center, and the local wedding registration office, all within the boundaries of the park. A pavilion at the edge of a pond provides an ideal backdrop for cooing newlyweds to pose for portraits.

A walk with Shi also makes it clear that much of the technology underlying sponge cities is, in fact, surprisingly low-tech. The real art of the approach lies not so much in being technically clever, but simply in being thoughtful. Shi explains, for example, that much of Shenzhen is underlain by a layer of clay, which prevents water from infiltrating very far into the ground. To make permeable pavements work means hiring contractors to dig out the clay, sometimes to a depth of six feet, and replace it with gravel and more permeable soil.

Nonetheless, once you get a sense of what to look for, Shenzhen suddenly starts to seem like an entirely different city. On the northwest side, a relatively new suburb called Guangming has wholeheartedly embraced the sponge city concept. The suburb’s recently built New City Park is a model of retaining stormwater in place, from a water-absorbing latticework in the parking lot to permeable pavement on the paths, to swales and miniature, artificial wetlands designed to slow and soak up water. The massive adjacent public sports center has a green roof and a vast expanse of permeable bricks and pavement. The anaerobic digesters at the Guangming water treatment plant are covered by an enormous green roof; there’s another at the foreign languages school. Over at the high-speed rail station, where bullet trains thunder in from Hong Kong, the streets out front are made of permeable pavement.

After a while here, it’s hard to resist the temptation to, little by little, empty your water bottle onto Shenzhen’s sidewalks and streets, simply for the novel sensation of watching the water disappear into what otherwise appears to be regular blacktop and concrete.

Back downtown, the Nature Conservancy’s Xin Yu shows me another side of the sponge city revolution. We meet in the lobby of a Hilton hotel just a mile from the Civic Center and the nearby hilltop statue of Deng Xiaoping. After quick pleasantries, Yu takes me out a back service door. Compared to the airy elegance of the hotel lobby, it feels as if we’ve passed through a portal into another dimension.

We find ourselves in the narrow alleyways of an area known as Gangxia, a former farming village that Shenzhen gradually engulfed, and that subsequently metamorphosed into a crowded warren of five- and six-story apartment buildings. Gangxia and other so-called urban villages are a phenomenon found in practically every Chinese city, and are testament to the frenetic pace at which the country has urbanized over the past 40 years. They are often gritty, but they’re an important haven for low-income migrants who otherwise wouldn’t be able to afford the high rents of most urban areas. They typically come to form largely self-contained communities with small businesses that cater to all the needs of their residents, from vegetable sellers to modest karaoke parlors.

Yu nimbly leads me through the narrow back alleys, and it quickly becomes clear that “village” is a misnomer. The densely packed buildings here are known as “handshake apartments,” built so close together that residents of neighboring buildings can reach through their windows to shake each other’s hands. Restaurants are preparing for the lunchtime rush, and the air is filled with the staccato rhythm of vegetables being chopped. Business here, Yu says, is vibrant and extremely competitive: “These alleyways really are alive.”

Gangxia’s original residents didn’t technically own the land upon which their houses were built, but they did have rights to use that land. As Shenzhen grew during the 1980s and 1990s, they replaced their own houses with apartment buildings, often keeping one floor for themselves and renting out the rest, to take advantage of rising rents.

The Nature Conservancy (TNC) has played an important role in showing that it’s possible to incorporate sponge thinking even in the heart of the urban jungle. “There are a lot of ideas, but the government or companies can’t necessarily try things out,” Yu says. “NGOs can. We can figure out what ideas work and take them back to the government to promote more broadly.” (Due to the current political climate in China, Shenzhen municipal officials were not in a position to meet for this story.)

Yu opens a gate to an otherwise nondescript apartment building and climbs several flights of stairs to the roof—and an improbable flourish of lush greenery. A multilevel lattice framework groans with plants of every description. This green roof, Yu says, catches over 65 percent of the rain that lands on it.

Showing what’s possible hasn’t always been easy. When TNC first started this green roof project, Yu and his colleagues had to contend with angry neighbors who thought they were illegally adding another story to the building. “People kept calling different government departments: the police, or the construction bureau, or the city administration bureau,” Yu says. That led to several visits from local code enforcement teams, who used ladders to gain access to the building and a cutting torch to try to dismantle the garden’s supporting framework. “They kept asking for approval documents,” Yu says, and laughs. “But those don’t really exist. We had nowhere to go to get them.”

With time, however, efforts like this have spread broader awareness of the sponge city concept. “Public consultation—how you get the public to understand what this is about—is very important,” says Liu of the Lincoln Institute. “I think NGOs can play a big role in this area, and TNC is a trusted international NGO in China.”

TNC’s work has also gained the backing of officials and business leaders. Yu was invited to be a member of the technical committee for Shenzhen’s municipal sponge city program. When corporate tech giant Tencent decided to incorporate sponge city techniques in its iconic new headquarters in Shenzhen, the company turned to TNC for ideas. And Tencent’s founder, chairman, and CEO, Pony Ma, is not only a member of TNC’s board of directors for China, but also a delegate to the powerful National People’s Congress. There, he has made sponge cities part of a broader personal platform of advocating for nature-based solutions. Ma has also inspired fellow business leaders to commit to—and invest in—ensuring that their businesses meet sponge city standards in Shenzhen.

Some 1,200 miles north of Shenzhen, in Beijing, Kongjian Yu’s office seems to sprout a plant from every spot where he hasn’t managed to stuff a book. The Where the Wild Things Are feel is entirely consistent with Yu’s personality, which is driven by a kind of restless energy. It’s hard to imagine him sitting in one spot for five minutes.

Yu, who was born in a small farming village in coastal Zhejiang Province, went abroad and earned a Doctor of Design degree at Harvard, in 1995. Upon returning to China, he was deeply disheartened by the direction that development had taken. “When I came back, I was shocked by the scale of urbanization,” he says. “I was amazed by how this process ignored all our natural and cultural heritage, filling in wetlands, destroying the rivers, cutting down the trees, and wiping out all these old buildings.”

Yu was hired as an urban planning and landscape architecture professor at Peking University. In the staid world of Chinese development theory, he has made his name as something of a flower child—and a gadfly. Yu became a prodigious author and tireless lecturer, and turned out a series of open letters to China’s top leaders. He called for China to abandon its mania for building monumental public squares; advocated for a revival of the traditional Chinese approaches to farming, water management, and settlement; and suggested that the money allocated for annual National Day parades be better spent building good parks.

Above all else, Yu railed against China’s obsession with concrete, a repudiation of decades of thinking here. “The philosophy in China, in Mao’s era, was that humans can beat nature,” Yu says. “And that caused a lot of disasters for us.”

That attitude only accelerated in the years after Mao’s death, and by the early 21st century, China was setting records for the amount of concrete it was pouring each year. Global systems demystification guru Vaclav Smil has estimated that China used more cement in just three years, 2011 to 2013, than the United States did in the entire 20th century.

While Yu has encountered opposition to his outspokenness, he has also tapped into a growing demand for this new kind of systems thinking. Today, in addition to serving as dean of Peking University’s College of Architecture and Landscape, he heads a 600-person landscape architecture and urbanism consultancy called Turenscape. Municipal governments across China routinely seek the company out for help. He wrote the definitive two-volume practitioners’ guidebook on sponge cities in China, and contributed to the Lincoln Institute of Land Policy book Nature and Cities. His work is also featured in Design with Nature Now.

A core tenet of Yu’s overall approach is a concept he calls fan guihua. The concept is frequently translated as “negative planning,” but might be more accurately rendered as “inverse planning.” It’s essentially a counter to the type of development that has shaped China’s growth for so long. “You plan what’s not built,” Yu explains. “You plan what should be protected.”

This, obviously, is a fairly radical idea in contemporary China. Yet in the course of his work, Yu came to a surprising realization: the idea of living with water, rather than battling it, was a concept that had historically been very familiar. In central and southern coastal China, including the area where Shenzhen now stands, a distinctive method had evolved over centuries to catch rainfall and carefully manage it with earthen dikes to raise mulberries, silkworms, and fish, a sort of landscape-scale aquaponics system. And when Yu and his students looked deeper, they realized that sponge city-like concepts had been a fundamental principle of Chinese city planning for centuries. Traditionally, he says, many Chinese cities had the capacity to absorb two-thirds of local rainfall within their boundaries.

With this discovery, the idea of a different way of managing water—and the perils of a drastically altered hydrologic cycle—became a major theme of Yu’s work. Nature, for its part, began putting an increasingly fine point on the issue. During the 2012 flood in Beijing, “seventy-nine people were killed. Drowned. On the street,” Yu says. “In the capital, we drowned 79 people. How is that possible? We lost face. That immediately became a political issue.”

Yu wrote another letter to high-level leaders saying that adopting the sponge city approach and creating a resilient landscape might offer hope. As it happens, Xi Jinping had recently become the secretary general of the Communist Party and president of China. After decades of the country struggling with notorious pollution and other environmental problems, Xi has staked his reputation on creating an “ecological civilization” in China.

The exact contours of that concept are sometimes difficult to discern, but in broad outline it encompasses both a nationwide push for ecological sustainability and the creation of a green, uniquely Chinese alternative development model for the rest of the world. Both sponge city thinking and a more expansive embrace of low-impact development fall squarely within Xi’s larger aspirations.

“China’s in an environmental crisis. We have to do this,” Yu says. “When people can’t breathe, when the water is polluted—I think he’s very sensitive to those issues. I think he really wants to build his legacy on doing this.”

The biggest challenge to making sponge cities work on a broad scale has nothing to do with building rain gardens, installing permeable pavement, or placating neighbors. “Finance is a major issue,” says Liu.

Liu, who came to the Lincoln Institute after 18 years with the World Bank, is largely focused on governance and financing issues associated with land use in China. Taking the sponge city concept to scale won’t be easy, and he cites the challenges in Shenzhen as an example. Sponge city improvements in Shenzhen, which officially began in 2017, now cover 24 percent of the city’s total surface area. The government has a goal of increasing that to 80 percent by 2030. But hitting that target will be a significant challenge.

The central government has pledged a total of $5.8 billion (40 billion Chinese yuan) to incentivize Shenzhen and the 29 other pilot cities to invest in and carry out sponge city work. But it wants each of those places to bring at least 20 percent of its developed area up to the sponge city standard by the end of this year.

Liu says that bringing a square kilometer of already developed urban land up to the standard typically costs $22 million to $29 million (150 to 200 million CNY). The 30 pilot cities are each eligible for 400 to 600 million Chinese yuan per year from the central government for three years. That’s enough to upgrade, at most, four square kilometers per year. To meet—and actually exceed—the central government’s 20 percent by 2020 target, Shenzhen brought about 235 square kilometers up to standard, at a cost that likely ran anywhere from $5 billion to $7 billion.

“Asking the municipal government to come up with that kind of money is not easy,” Liu says. Shenzhen was able to pull it off because of its strong municipal budget and private commitments from the city’s tech and manufacturing giants. But, he adds, “if you go to the interior cities where the municipal finance is very weak, it’s very difficult.”

Liu points out that in the case of new development, cities can implement standards that will require developers to pay for improvements, a cost typically passed on to residents and firms. “If you look at the upfront costs for development, sponge cities are not a very expensive thing to do,” Liu says. Retrofitting existing development, however, is a much bigger challenge.

“The toughest issue is that public finance is used to finance the public good, with very little opportunity for cost recovery,” he continues. “That’s really the toughest story about China. It’s a matter of priority. The cities just have too much on their plate. So by the end of the day, very few cities can find enough money.”

Sponge city infrastructure is “just like a streetlight,” Liu says. “It’s a shared public good, but nobody wants to pay for it.”

In truth, the biggest challenge of turning the sponge city into reality may well be unraveling the financing mechanics. Yet the cost of not rising to the challenge may be higher than anyone fully appreciates.

“It’s really like thinking about buying insurance,” Liu says. “We are all facing uncertainties, but the trend of more intense storms is quite clear . . . The cost of inaction might not look that high today, but when we’re faced with a catastrophic outcome in 10 or 20 years, we’ll regret that we didn’t spend the money earlier.”

Even given those high stakes, the sponge city idea could ultimately be about even more. Back in Shenzhen, standing on the roof of the apartment building in Gangxia, TNC’s Yu says sponge cities do a lot more than tame floods and save water for dry seasons. 

“If you only talk about stormwater management or runoff control, the average person won’t necessarily buy in, because they’ll feel like it doesn’t have any connection to them,” he says. “But features like green rooftops are different. They can have a synergistic effect. They help absorb rainfall, but they also improve the neighborhood view, contribute to urban biodiversity, and create a green space that everybody can use.”

Matt Jenkins, who has previously worked as an editor for Nature Conservancy magazine, is a freelance writer who has contributed to The New York Times, Smithsonian, Men’s Journal, and numerous other publications.

Photographs (in order of appearance):

Shenzhen, China, is one of 30 pilot “sponge cities” in China that are investing in nature-based stormwater management solutions. Credit: Wang Jian Xiong via Flickr CC BY 2.0.

Xiangmi Park, also known as Honey Lake Park, is a former agricultural research area in Shenzhen that was redesigned for community use. Bioswales, permeable pavement, and other elements allow it to double as a stormwater management tool. Credit: Vlad Feoktistov.

Rooftop garden on the Tencent Binhai towers in Shenzhen. Tencent founder and CEO Pony Ma is an advocate of sponge cities who has inspired fellow business leaders to invest in nature-based solutions in Shenzhen. Credit: The Nature Conservancy/Theodore Kaye.

A couple of years ago, landscape architect Pamela Conrad got curious about the climate impact of her work. How much carbon dioxide did her chosen materials release into the atmosphere? How much carbon was sequestered, or captured, by any given project’s mix of trees, shrubs, grasses, and other plants? What factors could she adjust to improve the net outcome? Conrad, a principal at the San Francisco firm CMG Landscape Architecture, decided to investigate.

“I went online and I just assumed there was going to be some magical tool that I could download, and it would just tell me,” she says. “I kind of expected to find it that afternoon.” That didn’t happen. She did find helpful tools and data intended to help gauge and improve the emissions impact of the built environment, but what she was looking for didn’t seem to exist: a tool to help landscape architects understand, in a holistic way, the climate impacts of their work.

Beyond her personal curiosity, this struck Conrad as a surprising absence. “We haven’t been measuring anything outside the building,” she says. That meant crucial conversations with policy makers and clients weren’t happening, because “we haven’t had the data.” Because landscape architecture can not only reduce emissions but also make tangible contributions to carbon sequestration, this field is perfectly positioned to offer “climate positive design,” as Conrad calls it: design that sequesters more carbon dioxide than it emits.

Conrad set out to make the tool she couldn’t find, with the support of a research grant from the Landscape Architecture Foundation. She worked with environmental consultants and tech developers to create a beta version of the free, web-based app now known as Pathfinder. The app, which formally launched in September 2019, has been used by 300 firms and counting. It is intentionally simple and accessible. Users enter various details of a project, large or small, from a backyard garden to a city plaza. The interface asks for information about materials (e.g., sand, crushed stone), plant types (e.g., trees, lawn), and other details.

On the back end, the app draws on data from sources including the U.S. Forest Service and the Athena Impact Estimator software created by the Athena Sustainable Materials Institute (ASMI) for building materials. It provides a kind of carbon profile for each project and offers suggestions to improve it, such as substituting a no-mow meadow for a lawn, or a wood deck for paving. The suggestions are intended to reduce the time it will take for each project to become carbon neutral, and then carbon positive. In the course of designing Pathfinder, Conrad tapped into a vein of similar efforts in other corners of the architecture and construction sectors that are contributing fresh insight to broader discussions of policy, planning, and land use. ASMI, a nonprofit collaborative, has been a pioneer on this front: since 2002 it has provided a variety of software tools that help designers measure the building, construction, and material impacts of their projects and materials.

Interest in this sort of resource is surging. Stephanie Carlisle, a principal at Philadelphia architecture firm KieranTimberlake, caused a stir earlier this year with a lengthy call-to-arms essay on the contribution of architects to climate change in Fast Company. New construction contributes massively to carbon emissions, she wrote: “Although it’s become mainstream to discuss energy efficiency and advocate for minimizing those impacts, architects, engineers, and planners have yet to truly reckon with the magnitude and consequences of everyday design decisions.”

Carlisle says she has been heartened by the enthusiastic response to the essay. As it happens, KieranTimberlake introduced its own carbon measurement tool, Tally, a few years ago. Tally was designed to be folded into workflow processes, as a plug-in to a 3D modeling software commonly used in the industry called Revit. This means, Carlisle explains, that a designer can substitute and change material and other options Tally allows architects to compare the climate impacts of various materials on a work in progress, then run a report on its potential carbon impact. “It tells designers where to spend their energy,” she says. Some 200 firms now use Tally, and its sales rose about 150 percent last year.

Tally, Pathfinder, and other similar tools fit into a broader trend of architects and landscape architects responding to climate change. “These [projects] are great pieces of the puzzle,” says Billy Fleming, Wilks Family Director for the Ian L. McHarg Center at the University of Pennsylvania and a coeditor of the recently published Design with Nature Now, a collaboration between the university and the Lincoln Institute of Land Policy. “The core of [the challenge] is absolutely about social, technical, and political systems that have to be reorganized around an international mobilization and response to climate change. So these efforts should be treated as the beginning of a conversation—not the end of it.”

Indeed, both Carlisle and Conrad emphasize that these tools are just a means to an end. Such tools are “directly empowering architects and engineers,” Carlisle says, but they can also help establish common benchmarks that make it easier for communication around carbon standards to “make its way into policy and code.” That’s starting to happen—Carlisle cites Marin County’s recent introduction of carbon standards for construction materials, and Conrad notes that San Francisco is embarking on a sustainable neighborhoods framework that factors in carbon sequestration standards—but they say there’s still not enough awareness of the possible positive impacts of design outside the design professions, or perhaps even within them. “We need way more investment in R&D, and in tools,” Carlisle says.

Conrad extends the point: as much as she intends Pathfinder to offer “really quick, accessible answers” with practical impacts on real projects, she also wants it to serve as an educational experience that builds awareness. “Landscape architects are the primary target,” she says. “But I see [potential use for] a lot of other players in the space, like policy makers using it to set standards.” While it’s easy for an individual to use Pathfinder to plan a backyard renovation, large-scale landowners can use it to gauge the impact of setting aside portions of development for trees and other elements that build climate resilience. A simple slider interface shows the user that, for example, a combination of 400 large trees and 1,100 medium-sized ones can sequester 2.3 million kilograms of carbon. “Once we’re able to measure what we’re doing and collect that data and get that feedback,” Conrad continues, “then we can start understanding what we’re doing and evolve our practices.”

Conrad has been spreading the word about Pathfinder through conferences and webinars, and has been taking suggestions that will guide updates in 2020. Late last year, she helped organize the Climate Positive Design Challenge, aimed at landscape architects, which established specific targets for projects large and small to achieve carbon-positive status: five years for parks, for instance, or 20 years for streetscapes or plazas. Pathfinder is meant to play a central role in helping designers meet that challenge. 

“We could potentially take a gigaton of carbon dioxide out of the atmosphere over the next 30 years,” Conrad says. “We think you can cut emissions [on a given project] in half, and increase sequestration by two or three times, just by having the right information in front of you.”

Rob Walker is a journalist covering design, technology, and other subjects. His book The Art of Noticing was published in May 2019. 

Photograph: The web-based app Pathfinder was the brainchild of landscape architect Pamela Conrad, who created the tool to measure the climate impacts of her work after discovering that no such tool existed. Credit: Courtesy of CMG Landscape Architecture.

Aún no me recupero de la experiencia de estudiar economía en el posgrado; allí, el saber general era que ciertos desafíos no pueden resolverse. Por ejemplo, una de las primeras lecciones fue que ningún sistema de votación puede llegar con fiabilidad a la “decisión correcta” que satisfaga una serie de principios básicos. Kenneth Arrow, Premio Nobel, demostró que ningún método de votación es justo, y que el único que no tiene fallas es la dictadura. Mediante el relato apócrifo de la “Tragedia de los bienes comunes”, aprendí que el acceso no restringido a los recursos comunes siempre terminará en el uso excesivo y la destrucción de dichos recursos. También aprendí que la acción colectiva por el bien común no tiene buenos resultados si involucra a más de siete personas. No es broma.

En mi camino de recuperación, detecté una falla en la secuencia adoptada por los economistas para analizar problemas. Primero, observamos la teoría para enmarcar la respuesta, y luego buscamos aplicar la estructura teórica para resolver la dificultad. Comenzamos con suposiciones que parecen razonables acerca de la conducta racional humana, como que la gente siempre prefiere más en vez de menos cuando se trata de algo bueno; si un votante prefiere al candidato A por sobre el B, y al B por sobre el C, entonces debe preferir al A por sobre el C (transitividad). Luego, construimos la dificultad en sí como una serie de elecciones hechas por agentes racionales. Inevitablemente, la teoría nos dice que algunas dificultades son insalvables, y que es imposible obtener una solución óptima. No importa cómo se computan los votos, siempre se encuentra un caso en que los votantes violan la transitividad de forma colectiva. Ya que más es mejor, los pastores pastarán de más y destruirán los bienes compartidos de pastoreo porque aumentarán el tamaño de su rebaño.

Pero, gracias a las palabras de dos filósofos más prácticos del s. XX, pude ver las cosas de otro modo: “En teoría, no hay diferencia entre práctica y teoría. En la práctica, sí” (atribuido a Yogi Berra); y “Una disposición de recursos que funciona en la práctica puede funcionar en la teoría” (conocido como Ley de Ostrom). Berra era un receptor de béisbol bajo y fornido que podía darle a todo lo que le lanzaban; y casi nunca lo eliminaban. Lo votaron como jugador más valioso de la liga tres veces y tiene el récord de cantidad de equipos con campeonatos mundiales. Elinor Ostrom, la primera mujer que ganó un Premio Nobel de economía, dedicó su carrera a demostrar cómo los grupos grandes de individuos que usan un recurso en común, como la pesca, encuentran formas de administrar la sustentabilidad de dicho recurso.

Resulta que muchas de las dificultades que los economistas consideran irresolubles también son existenciales. Tal vez la mejor forma de resolverlas sea probar cosas hasta encontrar algo que funcione. Uno de los mejores ejemplos, y de los más efectivos, de entrar en acción antes de ajustar todas las tuercas y tornillos teóricos es el Protocolo de Montreal (y también es un modelo potencial para abordar otros problemas mundiales complejos).

En la década de 1970, la gente empezó a notar que la capa de ozono de la atmósfera superior se estaba reduciendo en los polos, y en particular en la Antártida. La capa de ozono es lo que da el color azul al cielo. También permite que exista la vida en la tierra, porque absorbe la radiación ultravioleta nociva del sol. Poco más de una década después, los científicos concluyeron que la culpa recaía en la emisión de clorofluorocarbonos y otras sustancias que agotan la capa de ozono (SAO), compuestos artificiales para refrigeración, gases propelentes y materiales para la producción de plásticos, como el poliestireno extruido. El uso de SAO era extendido e iba en aumento, y la industria química no tenía alternativas ni una voluntad particular para desarrollarlas. Se hizo evidente que se necesitarían acciones a escala global para abordar la crisis de ozono, motivar a la industria para encontrar alternativas a estos químicos nocivos, convencer a todos los países posibles de que prohibieran el uso e hicieran cumplir la prohibición, y recolectar y reemplazar las SAO en refrigeradores e industrias existentes.

Los obstáculos parecían ser insuperables. Los voceros industriales popularizaron la “negación del ozono”: “¿Cómo llegan a 15.000 metros de altura los gases propelentes de mi desodorante, que se emiten a nivel del mar?”. “¿Cómo llegan a los polos las SAO emitidas en Topeka?”. Los científicos elaboraron respuestas a estas preguntas, convincentes, pero no definitivas: tormentas y circulación global. Pero con el aumento de la preocupación pública pasó algo extraordinario: incluso sin certezas científicas, los gestores de políticas, ambientalistas, científicos y líderes industriales decidieron que los riesgos que presentaba la disminución de la capa de ozono eran tan graves que ameritaban tomar precauciones.

En 1987, 46 países firmaron el Protocolo de Montreal para proteger la capa de ozono mediante la eliminación gradual de la producción y el consumo de SAO. Este entró en vigencia dos años después, y la implementación fue flexible y práctica. Dado que esta ciencia era emergente, los signatarios decidieron basar las futuras decisiones políticas en evaluaciones periódicas hechas por paneles de expertos mundiales en ciencias, medioambiente y economía. Para lograr que se unieran los 151 países restantes, los signatarios acordaron comerciar solo con otros signatarios. Enseguida adhirieron todos los países.

Para países de ingresos más bajos, sin los recursos necesarios para reemplazar las SAO, la implementación no fue punible. Se pidió a los países no cumplidores que trabajaran con un organismo de la ONU para preparar planes de acción y ponerse al día con el cumplimiento del Protocolo. En 1991, se fundó el Fondo Multilateral, por el que los países más ricos ofrecieron unos US$ 4.000 millones para ayudar a los de menores ingresos a cumplir con lo pactado. Hacia 2010, los 142 países signatarios en desarrollo lograron eliminar las SAO por completo.

El Protocolo de Montreal fue el primer tratado de la ONU de la historia en lograr ratificación universal. Esto demuestra que, a pesar de la teoría económica, es posible hallar soluciones colectivas a dificultades que parecen no tener solución. También demuestra algo particularmente crucial para estos tiempos: podemos afrontar las dificultades ambientales globales más complejas de forma efectiva y cabal. Las preocupaciones por la disminución de la capa de ozono pasaron de ser un problema ambiental periférico a ser impulsoras de cooperación nacional e internacional sin precedentes. Para este año, se eliminó gradualmente el 98 por ciento de las SAO incluidas en casi 100 químicos peligrosos del mundo. Los 197 signatarios cumplen con el Protocolo. Según las proyecciones, la capa de ozono volverá a los niveles de 1980 entre 2045 y 2065.

Un beneficio imprevisto del Protocolo de Montreal es la protección climática que ya logró. Al quitar de la atmósfera algunos de los gases de efecto invernadero más poderosos, el aporte del tratado para mitigar el cambio climático es mayor que el primer objetivo de reducción global del Protocolo de Kioto, centrado en el clima. Este último fue una extensión de un marco mundial establecido en 1992 para evitar la interferencia humana “peligrosa” en el sistema climático. Dicho marco, la Convención Marco de Naciones Unidas sobre el Cambio Climático (CMNUCC), propuso un objetivo simple: reducir la emisión de gases de efecto invernadero de todos los sectores para que el calentamiento global sea inferior a 2 ºC. Al igual que el Protocolo de Montreal, fue ratificado por 197 países y se basa en un panel de investigadores expertos para guiar y adaptar las respuestas políticas. Pero el cambio climático es mucho más complejo y polémico que proteger la capa de ozono. Hasta ahora, este marco no ha sido tan eficaz como el Protocolo de Montreal ni por asomo; si el aumento de la preocupación pública y los virajes políticos cambiarán esto, aún está por verse.

En 2000, luego de adoptar la Declaración del Milenio de las Naciones Unidas, se establecieron Objetivos de Desarrollo del Milenio (ODM) para todos los estados miembro. La declaración manifiesta que todas las personas tienen derecho a libertad, igualdad y un estándar de vida básico que incluye ser libre de hambre y violencia. Los ODM establecieron ocho metas específicas que se debían alcanzar para 2015 a fin de reducir la pobreza en todos los países, y hubo algunos logros: los estados miembro alcanzaron tres de las ocho metas, e hicieron grandes avances en cuatro de las cinco restantes. Para ayudar a los países en desarrollo a alcanzar las metas, los países desarrollados acordaron cancelar unos US$ 50.000 millones de deuda de los países pobres con deudas importantes.

En 2015, la ONU desarrolló una serie de Objetivos de Desarrollo Sustentable (ODS) para alcanzar los ODM. Los ODS son el marco político global más complejo hasta hoy, e incluyen 17 metas globales diseñadas para “lograr un futuro mejor y más sustentable para todos”. Un marco de informes obliga a los 193 estados miembro ratificantes a informar los progresos en 169 objetivos y 232 indicadores aprobados. Los ODS demuestran labores incluso más ambiciosas para trabajar de forma colectiva y abordar las dificultades globales.

Si bien estos marcos de políticas globales han triunfado en distintas medidas, tienen elementos importantes en común: reconocen el problema; en general, concuerdan en las causas y las soluciones; tienen metas idealistas, pero específicas; obligan a los países desarrollados a llevar la delantera (a veces, con recursos); poseen estructuras de monitoreo y evaluación; y, en los mejores casos, son acuerdos vinculantes que definen el cumplimiento e incluyen informes obligatorios.

Gracias al cielo, los economistas no se encargaron del diseño de dichos marcos. Todavía estaríamos esperando el marco teórico para las labores colectivas, antes de que pudiéramos empezar con la implementación. Por suerte, gente más pragmática se dio cuenta de que encontrar una solución estructural que satisfaga una serie de principios predeterminados es menos importante que actuar para superar una dificultad existencial y afrontar los obstáculos a medida que aparecen.

En el Instituto Lincoln, adoptamos un enfoque similar para cumplir nuestra misión global. El marco guía, nuestro Camino hacia el Impacto, ilustra nuestra estrategia para abordar seis desafíos sociales, ambientales y económicos con el uso de políticas de suelo. Establecimos objetivos a mediano plazo, y pronto identificaremos una serie de referencias con las cuales podemos hacer un seguimiento de los logros. En los próximos meses, alinearemos los objetivos y las referencias con los ODS correspondientes. Así, demostraremos nuestro compromiso y aporte para un futuro mejor y más sustentable para todos. También reconocemos que nuestro trabajo de campo no siempre se alineará con los objetivos estratégicos mejor elaborados, y estamos trabajando para mantener una flexibilidad suficiente para hacer frente a los obstáculos que surjan. Si algo aprendí es que la práctica hace imperfecta a la teoría, y que eso es bueno.

Fotografía: El Protocolo de Montreal es un marco global vigente de políticas con el cual 197 naciones tratan amenazas a la capa de ozono. Aquí, los representantes se reúnen en la sesión de apertura en la 28.º reunión de partes según el protocolo, en 2016. Crédito: Ministerio de Ambiente, Ruanda/Flickr CC BY 2.0.

Al igual que muchas ciudades costeras, Miami se enfrenta a un futuro climático que ya llegó. Incluso sin una tormenta importante, el agua de mar ha estado llegando a las calles y ha subido por el drenaje de las bañeras, un presagio de lo que vendrá cuando el aumento proyectado de medio metro del nivel del mar invada la tierra baja y porosa del sur de Florida, hacia mediados del siglo.

Esta amenaza no se está ignorando. Los planificadores y dirigentes políticos de la región metropolitana, basados en gran parte en la experiencia de lidiar con los infames huracanes de la zona, tienen una buena idea de qué hace falta para generar resiliencia: una combinación de barreras duras e infraestructura verde, que incluye la restauración de sistemas naturales para absorber y distribuir las inundaciones.

Hace dos años, los votantes aprobaron un bono Miami Forever de US$ 400 millones para ayudar a pagar un “futuro más fuerte y resiliente”; el dinero se distribuirá en cinco categorías: prevención de inundaciones, parques, vías, seguridad pública y viviendas asequibles. Se ha dedicado un énfasis particular a la protección de los vecindarios de ingresos más bajos, además de la de las legendarias propiedades de lujo frente a la playa. Esa yuxtaposición (por ejemplo, entre Little Havana, tierra adentro, y las elegantes torres de condominios de Brickell Bay Drive) ha despertado la consideración de cómo pueden aumentar los fondos quienes más pueden costearlo.

En Brickell Bay Drive, que se inunda de forma rutinaria, un rediseño propuesto de parque y rompeolas que incorpora un espacio verde y saneamiento de agua pluvial (con un costo estimado de hasta US$ 35 millones) ayudará a alejar el agua de algunas de las torres residenciales más distintivas de la ciudad. Pronto, el perfil de la ciudad incluirá dos torres de 305 metros que serán las más altas de la Costa Este al sur de Nueva York, que se lograron gracias a cambios en las restricciones de altura. Dado que estos desarrollos inmobiliarios privados tan exitosos se convierten en los principales beneficiaros de la infraestructura de resiliencia financiada por los contribuyentes, los funcionarios están evaluando cómo el sector privado podría cumplir un papel más importante para financiar el plan ecológico.

Jane Gilbert, directora general de la Oficina de Resiliencia y Sustentabilidad de Miami, dice que, cuando se trata de pagar la resiliencia, se consideran todas las opciones, incluida la captura de valor territorial, conocida como devolución de valor territorial, un mecanismo de financiación que recupera una parte de las inversiones financiadas por contribuyentes asociadas con los aumentos en valor territorial. Cada vez más evidencia indica una relación nítida entre la infraestructura verde y el aumento de valor de las propiedades; y, de hecho, la infraestructura de resiliencia no solo mejorará el valor de las propiedades, como lo demostraron los parques o las estaciones de tránsito. Lo más importante es que permitirá que los desarrollos privados sigan existiendo.

“¿Podemos hacer captura de valor para propiedades que están apenas fuera del parque [propuesto]? Tal vez”, dijo Gilbert. “Vamos a considerar todos los medios de financiación que podamos”.

Además de inspirar nuevos paradigmas en seguros, economía del hogar, agricultura, transporte y tantos sectores más, el cambio climático también obliga a las ciudades a revisar la relación fundamental entre la infraestructura que ofrece el gobierno y los bienes inmuebles que protege. La magnitud de la tarea (se estima que las comunidades del mundo gastan unos US$ 25.000 millones al año en infraestructura verde) requiere buscar financiación adicional.

La única opción es invertir

La relación entre infraestructura ofrecida por el gobierno y el sector privado viene de larga data. Propietarios, comercio e industria han gozado de la mayoría de los beneficios de canales, vías de tren, puentes y túneles, vías y muchas otras instalaciones desde que la república empezó a invertir en infraestructura de forma significativa. Las inversiones en infraestructura también se dispararon en momentos clave, cuando las ciudades se enfrentaron a problemas graves como enfermedades, superpoblación y congestión.

Hacia fines del s. XIX, las ciudades crecían rápido e intentaban acomodar la industria y una afluencia constante de inmigrantes. “Esta situación forzó la necesidad de invertir”, dijo Alex Krieger, profesor de diseño urbano de la Universidad de Harvard, director de arquitectura y planificación en NBBJ y autor de City on a Hill: Urban Idealism in America from the Puritans to the Present (Ciudad en la colina: idealismo urbano en Estados Unidos, desde los puritanos hasta el presente, Belknap Press 2019).

“Boston tuvo que construir un sistema de subterráneos porque se enfrentaba a una congestión total, estiércol de caballo en las calles y una ciudad con tamaño duplicado”, dijo. Lo mismo ocurría con proyectos locales que, hoy, la mayoría de los residentes consideran parte del paisaje, como la represa del río Charles; el rellenado de Back Bay, que es un ajetreado distrito residencial y comercial; y la creación del Collar Esmeralda de Frederick Law Olmsted, diseñado principalmente como sistema de saneamiento y control de inundaciones, además de ser un parque. “Lo que se temía era que las cosas terminaran siendo disfuncionales e incontrolables”, dijo Krieger. “Todo estaba más cerca del punto de ebullición, y no había más opción que invertir”.

Hoy, las ciudades están en un momento similar, reconocen cada vez más los estragos que está causando el cambio climático. Tal como el llenado de marismas permitió que existiera Back Bay, la infraestructura de resiliencia es la clave para el futuro del desarrollo urbano, y se puede decir que tiene un papel propicio aun más importante a medida que aumentan los riesgos climáticos.

La crisis actual no carece de soluciones. Muchos de los sistemas y enfoques para lidiar con el aumento del nivel del mar y las marejadas están a la mano, indica Billy Fleming, director del Centro McHarg de la Universidad de Pensilvania, y uno de los editores del nuevo libro del Instituto Lincoln de Políticas de Suelo Design with Nature Now (Steiner et al. 2019). Fleming ayudó a mejorar los 25 proyectos de infraestructura verde e hídrica presentados en el libro, que honra la doctrina de diseño ecológico del arquitecto paisajista pionero Ian McHarg (ver página 47).

Algunas de las intervenciones presentadas en el libro son un basural de Nueva York convertido en parque, un humedal en China construido para filtrar la contaminación de una ciudad planificada de 50.000 personas y una propuesta para construir relieves en la costa de Norfolk, Virginia que podrían absorber agua pluvial y mareas. El concepto fundamental detrás de este enfoque hacia la resiliencia, cultivado en particular por los holandeses a lo largo de los siglos, es combinar acequias, terraplenes, barreras y esclusas (la infraestructura “dura” o “gris” diseñada para mantener el agua a raya) con sistemas “blandos” que replican la naturaleza y dejan entrar el agua, para que se absorba y se distribuya.

Los proyectos del libro y otros parecidos reflejan innovación, experimentación y algunas pruebas y errores en diseño, y pueden servir de prototipos para distintas condiciones urbanas, dice Fleming. Pero además de los compromisos municipales, necesitan un marco organizativo más elevado para que se puedan escalar e implementar sistemas de infraestructura verde exitosos, a la par de prepararse para la guerra, construir un sistema interestatal de autopistas y llevar al hombre a la luna.

“Se trata de un problema nacional que necesita movilización a escala nacional”, dijo. Dice que los organismos federales, como el Cuerpo de Ingenieros del Ejército, deberán organizarse para administrar y financiar las mejores soluciones de adaptación al clima.

Siempre hay más para innovar, al igual que la NASA mejoró continuamente el diseño de sus cohetes. Pero las soluciones básicas de ingeniería, sugiere Fleming, ya están listas para implementarse. Para extender la metáfora, las soluciones de infraestructura verde son como los portaaviones y los bombarderos que se necesitaron en la Segunda Guerra Mundial: se demostró que podían cumplir bien su función, y fue sencillamente necesario construirlos e implementarlos. El asunto de la financiación estuvo sobreentendido en el caso de prepararse para la guerra, pero aun no se resolvió en el caso de la lucha contra el cambio climático.

“Si mañana decidimos que este es un problema tan real como fue el cólera en la década de 1870, encontraríamos el dinero”, dijo Krieger, de Harvard. “Solo se obtendrá consenso cuando se comprenda de forma colectiva que hay una crisis”.

Un enfoque con múltiples beneficios

El medio tradicional para financiar infraestructura se centra en préstamos a nivel federal, estatal y local. Dado que en general los fondos federales disminuyeron, algunas ciudades exploraron nuevos mecanismos de bonos que aclaran cómo las inversiones y la sustentabilidad pagarán dividendos en el futuro. En Washington, DC, un programa de bonos verdes ofrece capital para vías fluviales y gestión de agua pluvial y cloacas, según el rendimiento mensurable de dichas labores. La emisión inaugural de 2014, de US$ 350 millones, fue el primer bono municipal de un siglo en el país (dura 100 años), y se hizo conocido por su estabilidad y el gran rendimiento.

La lógica de ese enfoque es inherente al Bono de Impacto Ambiental, que, según la empresa financiera Quantified Ventures, ofrece anticipo de capital de inversionistas privados para proyectos ambientales, ya sea para hacer un piloto de un nuevo enfoque cuyo desempeño se considera incierto o para escalar una solución probada en un programa piloto. 

Si bien los inversionistas más cautelosos consideran a la infraestructura verde como nueva y no demostrada, en realidad tiene un poder extraordinario. “La infraestructura verde ofrece múltiples beneficios a la sociedad, entre ellos resultados ambientales, económicos y sanitarios”, dice Eric Letsinger, fundador de Quantified Ventures, que se centra en proyectos con impacto social y ambiental positivo.

Las prácticas de infraestructura verde pueden dar resultados positivos en salud, por ejemplo, que resultan en reducción de costos en sistemas y planes locales de salud. Letsinger dijo que al involucrar a otros sectores para pagar la resiliencia se podría abordar el problema de los “bolsillos incorrectos” (el escenario económico por el cual una entidad costea una inversión que genera beneficios para otras) que “históricamente evitó que los beneficiarios económicos de la infraestructura verde, como los socios de salud, pagaran su parte de los costos de implementación”.

De modo similar, algunos de los que más se benefician a nivel económico son los dueños privados del suelo y las propiedades. Un informe de 2017 publicado por Urban Land Institute cuantificó cómo los mecanismos de gestión hídrica que usan infraestructura verde pueden crear valor para proyectos inmobiliarios al mejorar la eficiencia operativa, además de funcionar como servicio atractivo. Una de las moralejas esenciales era que los sistemas de resiliencia natural pueden aumentar la viabilidad económica (Burgess 2017).

“Encontramos muchos ejemplos de incorporación consciente de infraestructura verde que llevó a aumentar el valor de las propiedades”, dijo Katharine Burgess, vicepresidenta del programa de Resiliencia Urbana de ULI. Dijo que la infraestructura verde se puede amortizar en términos de ahorros en costos operativos. Se puede integrar en el diseño y la creación de entornos, aportar servicios y valor de mercado, y puede terminar siendo un beneficio complementario de liberar terrenos desarrollables para aumentar el rendimiento.

De hecho, una nueva matriz de evaluación de riesgos y debida diligencia en bienes inmuebles se centra en el cambio climático. Otra encuesta de ULI para inversionistas y desarrolladores concluyó que los factores como el riesgo climático y la vulnerabilidad a inundaciones cobraron cada vez más importancia entre quienes consideran desarrollar, adquirir o invertir en propiedades (Burgess y Rapoport 2019). “Definitivamente, está cambiando el aire”, dijo Burgess.

Para la comunidad de desarrolladores, la conclusión parece ser lo que por intuición se comprende a gran escala: los terrenos más altos y protegidos son más valiosos.

“A fin de cuentas, no se trata de códigos de edificación, seguros ni tecnología; se trata del uso del suelo”, y los riesgos, choques y estrés relacionados con la utilidad del suelo, dijo Jesse Keenan, de la Universidad de Harvard. Él dirigió una investigación que demuestra que las propiedades más bajas de la zona de Miami están mucho menos valoradas que los lugares altos y secos (Keenan 2018).

Keenan acuñó el término “aburguesamiento climático” para describir cómo los vecindarios tierra adentro, como Little Haiti, de pronto son más buscados. Ante la ausencia de infraestructura de resiliencia que proteja contra la subida del mar, el suelo que es más alto que el promedio de Miami, de dos metros sobre el nivel del mar, es un refugio.

Colaboración pública y privada 

¿Hay una forma de cuantificar los beneficios de la infraestructura verde para extender la responsabilidad de pagarla? Miami no es la única ciudad que está considerando mucho el concepto. En Boston, los planificadores encargaron un estudio en una sección de la costanera de East Boston que incluye el “potencial de captura de valor de nuevos desarrollos en la costanera para financiar infraestructura de resiliencia basada en usos existentes y potenciales a futuro” (BPDA 2018).

La zona de estudio incluye una franja larga de terrenos desarrollables que se rezonificará del uso industrial y marítimo, dando paso a desarrollos de uso mixto con mayor altura y densidad; pero eso también corta directamente camino a las futuras inundaciones anticipadas. “Es un debate de igualdad . . . [la potencialidad de] que los desarrolladores ayuden a pagar la infraestructura que los proteja no solo a ellos, sino [que proteja] también tierra adentro”, dijo Richard McGuinness, director adjunto de cambio climático y planificación ambiental en la Agencia de Planificación y Desarrollo de Boston.

En la sede central de Gillette, junto al canal Fort Point, en Boston, se está desplegando una versión más modesta de colaboración pública y privada: la empresa se prepara para otorgar el derecho de paso y hacer una barrera contra inundaciones que financiará la Agencia Federal para el Manejo de Emergencias. Los costos del proyecto se cubrirán con fondos del presupuesto de capital de la ciudad asignados a la resiliencia. En el fondo, el gesto de la empresa es un acto de supervivencia (la fábrica de rasuradoras está junto al agua), pero los funcionarios de la ciudad se sienten alentados por el reconocimiento de que para construir resiliencia las empresas y el gobierno deben trabajar en sintonía.

Otras regiones metropolitanas de Estados Unidos también exploran cómo la infraestructura verde genera valor, y están aprovechando ese poder con creatividad. En Pittsburgh, se asignó una parte de unos 10.000 lotes vacíos y evasores para hacer renovaciones ecológicas (granjas urbanas, jardines comunitarios, parques pequeños y proyectos similares) que se podrían financiar mediante transferencia de derechos de desarrollo. El enfoque garantiza que las parcelas no se quiten de la nómina impositiva porque los derechos de desarrollo se usarán en otras zonas planificadas para redesarrollo de terrenos vacíos. Al mismo tiempo, los parques y jardines comunitarios aumentarán los valores de propiedad en zonas que antes estaban deterioradas, dijo Roy Kraynyk, vicepresidente de Allegheny Land Trust (Kraynyk 2017).

Mientras tanto, en Sudamérica las investigaciones sugieren que los mecanismos bien establecidos de captura de valor territorial en Colombia (que se usan desde hace mucho para respaldar proyectos de infraestructura más tradicional relacionados con viviendas y tránsito) se podrían llegar a usar para la resiliencia. Un equipo de investigadores dirigido por Stelios Grafakos, economista principal en Global Green Growth Institute, evaluó el impacto de la infraestructura verde en el valor del suelo en el proyecto junto a un río en Santiago de Cali, Colombia, conocido como CAU Cañaveralejo (Grafakos 2019).

El modelo hedonista de precios que desarrolló el equipo, con la ayuda de análisis de GIS, “demuestra cuantitativamente un aumento útil en el valor del suelo, atribuible a las inversiones de capital en resiliencia y reducción de riesgos. . . . Los aumentos del valor territorial se pueden atribuir a las inversiones en medidas de resiliencia, como la implementación de sistemas urbanos sustentables de drenaje, corredores verdes para gestionar inundaciones, restauración de terrenos anegables naturales y espacios públicos multifunción para recreación y gestión de agua pluvial” (Figura 1).

Calcular el valor de la infraestructura verde

La infraestructura verde es, en esencia, una herramienta para gestionar el agua pluvial; también “crea servicios que pueden elevar el valor de las propiedades y ofrecer beneficios a la salud”, dijo Robin Hacke, directora ejecutiva del Centro para la Inversión Comunitaria (CCI, por sus siglas en inglés) del Instituto Lincoln. El CCI trabaja con ciudades como Miami, Milwaukee y Seattle para identificar y obtener financiación para proyectos de resiliencia, como infraestructura verde y viviendas asequibles. Hacke dijo que la captura de valor territorial es un “enfoque alentador” que se está incluyendo en las conversaciones. Es probable que dichos debates ganen impulso, dado que cada vez más investigaciones indican que la infraestructura verde aumenta el valor:

• “En Boston, el complejo 1330 Boylston . . . vio aumentos de alquiler de US$ 300 a US$ 500 al menos para unidades con vistas a un techo verde de US$ 112.500; y pronto ganaron unos US$ 120.000 al año” (Burgess 2017).
• “Los entornos ecológicos de alta calidad pueden ayudar a . . . estimular los alquileres hasta un 20 por ciento” (UKGBC 2015).
• “. . . los valores de propiedad tasados en las propiedades industriales de Menomonee Valley fueron un 5,8 por ciento más altos de lo que habrían sido sin infraestructura verde” (Madison 2013).
• “Los estudios hedonistas demostraron que un riesgo inferior de inundaciones puede resultar en un aumento del 2 al 8 por ciento en el valor de las propiedades” (Clements 2013).

Con la aparición de estos datos, las ciudades que buscan la adquisición por parte de los desarrolladores podrían ver que tienen una base más sólida. Pero Hacke ofreció una advertencia: a medida que aumentan los valores, también aumenta el riesgo de desplazamiento. Dijo que las ciudades deben priorizar la asequibilidad e invertir en proyectos que “protejan la capacidad de la comunidad de quedarse en el lugar”.

En total, el proyecto produjo un aumento general de los valores de US$ 2,2 millones en 48 manzanas y 9 vecindarios: un incremento de alrededor del 7 por ciento. El trabajo, que aún está en curso, incluye plantaciones de árboles, y creación de espacios verdes, bicisendas y senderos peatonales.

Uno de los coautores del artículo lleva el concepto un poco más allá y sugiere que el beneficio más tangible de la infraestructura verde puede ser que protege contra las pérdidas. “En algunos aspectos, para financiar la adaptación a las condiciones climáticas mediante la captura de valor territorial se requiere invertir la premisa fundamental del concepto: más que crear valor, las inversiones en adaptación sirven para preservar el valor que, de otro modo, disminuiría o se pagaría”, dijo James Kostaras, miembro sénior del Instituto de Desarrollo Urbano Internacional.

Kostaras sugiere que, en ese marco, “un poco de incremento en el valor territorial que se conserva y se protege con las intervenciones de adaptación climática se moviliza como fuente de financiación para mitigar el impacto de las inundaciones y otros eventos ocasionados por el clima”.

Las propiedades de Miami que se inundan o están cerca de calles que se inundan ya perdieron US$ 125 millones desde 2005, según una investigación compilada en la iniciativa educativa en línea Flood IQ. Las futuras pérdidas se duplicarán fácilmente en los próximos 15 años, y esa proyección no incluye las propiedades nuevas que entren en riesgo desde hoy hasta 2033 (First Street).

Visto de otro modo, los nuevos desarrollos privados en cualquier zona vulnerable a los impactos del cambio climático crea una carga para el público, porque la gente y la propiedad necesitan protección. Como tales, los aportes del sector privado a la infraestructura verde son más parecidos a extracciones de desarrollador o tasas de impacto, que se han cobrado a los constructores de desarrollos suburbanos convencionales durante décadas para ayudar a pagar la extensión de servicios públicos a las áreas que antes no estaban desarrolladas.

Nuevas formas de pagar la innovación

Al reconsiderar la relación entre inversiones públicas y desarrollo privado, la infraestructura de resiliencia podría convertirse en el servicio de la ciudad más crítico, junto con protección policial o de bomberos o servicios de agua, cloaca y electricidad. Mantener el agua a raya ha adquirido importancia primordial. “Es algo prioritario”, dijo Enrique Silva, director de Iniciativas Internacionales e Institucionales del Instituto Lincoln.

Agregó que será complejo medir los beneficios de dichas estructuras. En la mayoría de los mecanismos de captura de valor territorial, el impacto de las inversiones públicas se mide de una manera más lineal; por ejemplo, el “estímulo” del valor territorial en un radio de un kilómetro de una nueva estación de tránsito. Con la infraestructura verde, el impacto en valor territorial se expande a un ecosistema más amplio, y podría producir variaciones importantes en términos de asignar obligaciones financieras. ¿Las propiedades más cercanas a la intervención son las que más se benefician? ¿O las que están a kilómetro y medio río abajo gozan de las protecciones en la misma medida? ¿O todo el suelo y las propiedades en un “distrito de resiliencia” especial se deberían tratar del mismo modo?

“Se podría argumentar que es menos complejo con una nueva línea de metro”, dijo Silva. Dijo que los gobiernos “deberán tomar esa decisión: definir la zona de influencia”.

Para otros, es una incógnita que los sistemas naturales sean un impulsor tan singular del aumento de valor de propiedades. David Martin, desarrollador de Miami, director de Terra Group, dijo que le gustaría ver una “fuente de financiación fija para infraestructuras que no dependan de fuerzas macroeconómicas que suben y bajan”. Según su opinión, la infraestructura de resiliencia es uno de varios factores que determinan el valor del suelo; otros son cosas como tasas bajas de interés o la calidad del sistema escolar local.

Dichas calibraciones son indicadores del arduo trabajo que nos espera, pero el ímpetu por encontrar nuevas formas de financiar la acción climática no mermará. “Las dificultades de invertir en infraestructura que encuentran los gobiernos locales son demasiado grandes para resolver con soluciones corrientes”, dijo Letsinger, de Quantified Ventures. “Deberán innovar para escalar esta montaña, y si pretendemos que innoven, entonces debemos proporcionarles nuevas formas de pagar la innovación”.

Letsinger y otros enfatizan tanto en la urgencia de construir resiliencia climática como en la disponibilidad en tiempo real de soluciones. “No debemos esperar”, dijo. “Ahora, las ciudades tienen las herramientas, los medios y el acceso a capital para avanzar con los proyectos de resiliencia que necesitan”.

Anthony Flint es miembro sénior del Instituto Lincoln de Políticas de Suelo y editor colaborador de Land Lines.

Fotografía: La costa de Miami es un área altamente desarrollada vulnerable a las inundaciones y al aumento del nivel del mar. Crédito: Gunther Hagleitner a través de Flickr CC BY 2.0.

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