Tag Archives: #marshland

Chennai Ran Out of Water: Part 3

India Currents, in collaboration with bioGraphic and the California Academy of Sciences, is publishing the last in a 3 part series on Chennai’s restoration of its marshlands. Read Part 1 and Part 2 of this story! 

(Featured Image: Mylapore Tank holds water even during the dry season, but only because its bottom has been paved over.)

Temple tanks

As in most Indian cities, Chennai’s piped water supply is available for just a few hours a day. And many parts of the city have no water connection at all. So many people pump groundwater, either on their own property or from government wells on the street. Others hire tanker trucks to fill their cisterns with water that has also been extracted from underground. “A huge quantity, almost 200 MLD [million liters daily] of water, is being shipped every day,” a water utility official told me. But surface and groundwater are not separate sources; they are linked by gravity and hydraulic pressure. So when people pump groundwater, they are ultimately depleting surface water as well, and near the coast, they are turning their water salty. 

With little monitoring and few restrictions, the city’s groundwater table is dropping by some 10 to 20 centimeters (4 to 8 inches) every year. That’s why finding creative ways to recharge groundwater within the dense, paved city is a critical step toward having enough water for people and for nature. And that’s where many small projects come into play. Recharge wells are becoming more common around neighborhoods in Chennai, their round perforated covers, a little larger than manholes, pocking city streets and sidewalks. Those covers lead to wells averaging 4.5 meters (15 feet) deep that simply give water a path into the permeable subsurface, and eventually into the aquifer. 

Through water as leverage, Madras Terrace, a local architecture firm, has proposed another approach to getting water into the ground across the city: temple tanks, a remnant of the eris system. In the past, “you cannot find a village without a temple, and you cannot find a temple without a water body,” says KK. Lots of those villages and temples have now been subsumed by the city.

One bright, blue-sky day, just before I leave India, I meet with Sudhee NK, an engineer and financial planner with Madras Terrace. We rendezvous in charming, bustling Mylapore, a neighborhood centered around Kapaleeswarar Temple, marked by a 37-meter-high (120-foot-high), pyramidal tower intricately carved and painted with some of Hinduism’s more than 3,000 gods. Vendors sell flower offerings, clay cups meant to be broken after drinking, and small deities. One of Chennai’s most notable tanks, occupying a city block, sits alongside the temple. With its top at street level, an inverted, stepped pyramid descends into the ground so people can continue to access water as the table falls.

Sudhee explains that, historically, the tank bottoms were unpaved so that groundwater replenished the tank from below, and rain and runoff from above helped to recharge the water table. Temple tanks were connected to larger eris systems and also served ritual purposes. Today the Kapaleeswarar tank holds water—ducks swim along the side and turtles bask in the sun—but only because the bottom was paved about 10 years ago to retain water for religious ceremonies. This water is effectively a mirage, says Sudhee.

To show me the true status of the water table here, he leads me across the street to another temple tank, Chitrakulam Pond, believed to be more than 2,000 years old and not cemented. Its bottom is carpeted with a mat of fresh grass, sprouted from recent rains, but the water has descended deep underground. “This is the real situation,” says Sudhee. Too much pavement and too many borewells are to blame for water levels more than 18 meters (60 feet) below the surface, he says.

Tanks that have not been paved over reveal the true state of Chennai’s water table, which, during the dry season, often lies dozens of feet below ground.

Sudhee and colleagues want to restore temple tanks across Chennai to their natural, unpaved state, to move water underground. The city government, Greater Chennai Corporation (GCC), is connecting stormwater drains to temple tanks wherever possible to allow for groundwater recharge. And Sudhee’s team is also helping to raise the water table by collecting rainwater from buildings via vegetated ditches, called bioswales, placed strategically along streets, on hotel properties, in backyards, and in schoolyards. The Mylapore project is expected to provide on average 4 million liters (1 million gallons) of water per day. Replicating the project across 53 other temple tanks in Chennai could result in 60 million liters (16 million gallons) per day of recharge, according to the Water as Leverage team’s projections.

Reconnecting with culture

Despite stated government support for these slow water projects, getting utility engineers to embrace green solutions is difficult, says Balaji Narasimhan, the hydrologic engineer who is also involved in the Dutch-local partnership. That’s in part because the systems are more complex than concrete-lined drainage channels, levees, and dams. Slow water projects usually have a biological component, such as plants that may require soil amendments to achieve the chemistry or filtration they need. Silt traps must be cleaned. Also, because such projects tend to cover a larger area than concrete solutions, the public is more likely to come in contact with them, so project managers need to cultivate community support. But that requirement can be a benefit, says Narasimhan, reconnecting people with their water. 

KK tells me, “Even 200 years ago, people used to worship rivers as goddesses. Because of that, we were preserving water. Now we’ve lost those cultural values; we forgot.” When water “magically” arrived via centralized distribution, people stopped caring for their water bodies. In North Chennai, parts of which remain somewhat rural, Jayaraman, the activist, has witnessed that loss in a single generation. “Among the older people, there is a far more intimate knowledge of hydrology, of seasons,” he says. “Among the younger people, that is eroding quite quickly. It erodes with the landscape. Your culture goes with the landscape.”

But the reverse may also be true. As government agencies and NGOs hold and reclaim space to reestablish slow water, and as people harvest some of their personal water from local supplies, Narasimhan says he hopes they will become newly motivated to keep them clean and replenished. 

One project is directly targeting the next generation. On a warm, partially overcast day in early December, I grab an autorickshaw to Tholkappia Poonga Eco-Park, a 24-hectare (58-acre) green oasis in the heart of the city, near the mouth of the Adyar River, which bisects Chennai. Separated from the beeping traffic outside by concrete walls, the tree canopy is thick here, and the peaceful walking paths and the air above are bustling with butterflies, beetles, blue-and-yellow grasshoppers, crane flies, lizards, lorikeets, and other birds. 

Despite the significant loss of wetland habitat, an astounding array of native biodiversity clings to life in and around Chennai.

Years ago, an area creek feeding the river was filled in for development and this place became a dump, piled high with garbage and human waste and used for illegal activities. To counteract pollution and biodiversity loss, local NGO Pitchandilkulam Forest Consultants and city agency Chennai River Restoration Trust began restoring the area’s former river and estuary habitats 12 years ago. 

My guide during this visit is K. Ilangovan, an ecologist and wetlands specialist who has overseen this project from the beginning and has himself planted thousands of trees, including mangroves and 250 other species of plants. Since forest restoration here began, he’s observed snakes, mongooses, mice, and even jackals that feed on crabs and fishes. “We didn’t introduce anything here,” he says. After the replantings, “everything came.”  

People from nearby neighborhoods were involved in the planning and planting so that they would better understand the area’s purpose, and some still have jobs here taking care of the plants. During the monsoon, the whole park becomes flooded, storing water, says Ilangovan, and the surrounding neighborhoods have seen higher water levels in wells and reduced flooding, including during 2015, when they were spared the worst of the flood. The microclimate has also changed, keeping it a little cooler than the concrete jungle elsewhere in the city. The third phase of restoration is now underway; ultimately 145 hectares (358 acres) will be restored. 

Aside from offering homes to a variety of creatures in the middle of the city and mitigating water problems, the Eco-Park is a favorite field trip destination for school children, who come here and are blown away, says Ilangovan. Living in the city with little exposure to nature, “They are so happy to touch and feel the plants. You can see the brightness in their faces.” That outreach is critical to changing the direction of society, he says. “We can’t go and change the people with 40 or 50 years’ age,” he says. “So I focus more on the kids.”

Amidst growing environmental awareness of the general public and the government, four of the seven projects proposed by the Dutch-local partnership are moving forward, says Jayshree Vencatesan, including the Mylapore tank and Muttukadu Backwaters. Separately, her nomination of Pallikaranai as a Ramsar site, a wetland of international importance, is under consideration by the central government in Delhi. But development pressure remains intense. “We as a country are trying to become more of a wealthy nation,” says Vencatesan. “And if we assume that people don’t want that, we are wrong.” 

Back at Pallikaranai Marsh, walking down a muddy path at the edge of shallow open water, we pass trees planted by Care Earth Trust, trunks wrapped in cuttings of an unpalatable plant to deter nibbling cattle. Bee-eaters and kingfishers whiz by, and a fan-throated lizard darts under a rock. The sun glints off an iridescent green jewel beetle with black spots, bumpily navigating stems and leaves. Antennae waving about, it suddenly flips, revealing a bright orange undercarriage. There’s still plenty to amaze here.

Educating people about the value of water systems and biodiversity is a long-term process, says Vencatesan, one that she’s been working toward with her characteristic persistence for decades. Near the spot where I was stuck in the minivan, she is planning to reroute traffic away from the marsh and build a pedestrian “ribbon walk,” where people can interface with nature. “They should see a value in it,” she says. “Otherwise, it’s not going to last.”

Go back and read Part 1 and Part 2 of this story!

Erica Gies is an independent journalist who covers science and the environment from Victoria, British Columbia, and San Francisco, California. Her work appears in the New York Times, Scientific American, Nature, Ensia, The Economist, bioGraphic, National Geographic, and other outlets.

Photographs by Dhritiman Mukherjee.

This story originally appeared in bioGraphic, an online magazine about nature and sustainability powered by the California Academy of Sciences.

Chennai Ran Out of Water: Part 2

India Currents, in collaboration with bioGraphic and the California Academy of Sciences, is publishing a 3 part series on Chennai’s relationship with water. Find Part 1 here!

The Eris System

The people of Chennai don’t have to look far for inspiration on how to work with nature to finesse water cycles. Starting at least 2,000 years ago, ancient Tamil people ensured that they had water year-round by building a series of connected ponds on a slope from the Eastern Ghats (“mountains” in Hindi) east to the Bay of Bengal. These eris, the Tamil word for tanks, are open on the higher side to catch water flowing downhill, while the lower side is closed with an earthen wall called a bund. An overflow divet in the top of the bund gives excess water a path to continue on to the next eri downhill. “System eris” were built off of rivers and creeks to capture their peak flows, while “non-system eris” were dug in areas without natural waterways to capture rainfall in a series of connected depressions. Eris were described in early Tamil literature and temple engravings, says Krishnakumar TK, an amateur historian and local travel writer who works in information technology and goes by the name KK.

The eris system is the opposite of modern development’s tendency to move water off the land as fast as possible. The early Tamils understood that, by slowing water’s flow, the eris reduced flood peaks and prevented soil erosion. They gave water time to seep underground, filtering it and keeping the water table within reach of wells. The eris also served as visual indicators of water availability because they were connected to the water table, says Vencatesan. Seeing the water level in a pond signaled to farmers when to sow their crops. Cultural rituals dictated system maintenance and water sharing. Tanks were also part of every temple complex, bringing water into the heart of religion and culture.

And because many eris were connected to creeks, rivers, coastal wetlands and freshwater marshes, they provided natural waterways their due along the way. Even eris not directly connected to rivers helped to feed the local hydrology because underground aquifers are extensive, so water absorbed in one place could feed a river some distance away. The words “lake,” “tank,” and “water body” are interchangeable here because, after so many generations, no one remembers whether a particular water body is natural or human-made. 

British engineers in the 19th century were amazed by the scale of the eris system—reportedly more than 53,000 bodies of water across southern India—and the deep knowledge of topography and hydrology required to build it. Alas, British respect had limits. Their centralized management supplanted the traditional system by which villages managed their local eris themselves, removing accumulated silt each year and using it to fertilize fields. The British neglected this maintenance and the eris fell into disrepair, making it easier to justify filling them in and building on top of them—a pattern that continued after independence.

As they built roads, the British obliterated the flow pathways that had linked water bodies, says KK, giving the rainwater nowhere to go. “They did not understand our system,” he says. Today, many famous city landmarks and neighborhoods—Loyola College, Central Chennai Rail Station, T. Nagar, Nungambakken—sit atop former tanks and lakes, says KK. Street names such as Spur Tank Road and Lake View Road commemorate ghost water bodies that once sustained and protected their neighborhoods. Fewer than one-third of the 650 water bodies that KK has documented in and around Chennai remain. The surface area of water decreased from 13 square kilometers (5 square miles) in 1893 to less than 3 kilometers (1.1 square miles) today, so in heavy rains, water floods into city streets, homes, and businesses.

Ironically, given KK’s passion for finding and documenting historic water bodies, the IT company he works for is in a special economic zone built atop Pallikaranai Marsh and the neighboring Perumbakkam wetland. He chuckles ruefully, showing me the area on a map. “We used to have hundreds of thousands of migratory birds visiting this marshland some 20 years ago. I have seen [it] getting destroyed in front of my eyes.” With just 10 percent of the marsh area remaining, “Even I can’t [see] the water from my workstation, and I’m on the fourth floor.” But as the title of Krupa Ge’s book invokes, Rivers Remember. This area hasn’t forgotten it is a marsh. During the 2015 monsoon, it flooded to the second floor.

Kids bird watching at the Marsh.

Wetlands = wastelands

Another British legacy that facilitated the destruction of wetlands was their official designation as wastelands. To Jayshree Vencatesan, the notion of wetlands as wastelands is anathema. “I grew up in the hinterlands, where this notion of waste doesn’t exist,” she says. “To us, nothing is a waste.” That attitude was once widely shared across southern India. Many areas the British saw as “waste” were shared-use commons, called poromboke in Tamil and dating back to medieval times. The ethic surrounding the use of the commons is even older, says Vencatesan, rooted in Tamil scriptures, which described the resources that wetlands provide—fish, seasonal agriculture, fodder for animals, medicinal plants—as well as the requirement to protect them, including penalties for those who didn’t. People understood and accepted that wetlands and other ecosystems were multifunctional habitats, supporting not just humans but other organisms as well. As a common property resource, water was subject to rules regarding how it was allowed to overflow from one water body or wetland to another. “This is essentially upstream-downstream equity, you know?” she says.

As she learned more about wetlands throughout her career, in part by working with Indigenous people who continue to live close to the land and water, Vencatesan internalized those values of multipurpose landscapes. She also learned that it’s critical to allow certain wetlands to follow their natural rhythm and go dry part of the year, to support the natural life cycles of animals and plants, including crops. “All of our melons and gourds and stuff like that used to be grown when the moisture is retained, but the surface flow is not there.”

In contrast, the British viewed land as property, so the commons, which could not be bought, sold, or built upon, “presented a very peculiar problem for them,” says Nityanand Jayaraman, who goes by Nity. A local community activist with a collective called Vettiver Koottamaippu, he works in North Chennai, where industrial facilities like coal plants are displacing fishing communities. “From a revenue point of view, it was wasteland.” As surrounding lands were developed, tension mounted over these two sets of competing values. “Of course, the old values lost,” he concludes. “And what we have is a disaster called Chennai.” 

The lost values are arguably as significant as the declines in sustainable subsistence and healthy, functioning ecosystems. People’s identities are entwined with their place. When development annihilates a place’s natural heritage, people also suffer cultural loss—loss of identity. For example, Pallikaranai Marsh is home to neithal (Nelumbo sp.), an endemic, striking, blue-violet water lily, one of the earliest flowers described in Tamil literature, says Vencatesan. Other beloved creatures of the swamp include the glossy ibis (Plegadis falcinellus) and, perhaps surprisingly, the hump-nosed viper (Hypnale hypnale), one of India’s four venomous snakes. “Snakes are revered in Tamil Nadu,” says Vencatesan, who grew up in a neighboring state. “They think it’s a god, so, yeah, they have no problem with snakes.”

Today Chennai’s wetlands are still officially classified as wastelands, which has made Care Earth Trust’s progress thus far, conserving 620 hectares of Pallikaranai Marsh, all the more remarkable. The organization is also working to restore numerous other “wastelands” that are, or were, connected via water pathways to Pallikaranai. On a visit to a few of these sites with Care Earth staff, I see candle flower (Senna alata), a medicinal plant whose flowers exude a milk that soothes skin injuries, as well as bronze-winged jacanas (Metopidius indicus), fish eagles (Icthyophaga humilis), black bazas (Aviceda leuphotes), northern shovelers (Spatula clypeata), and many other native species.

At Thalambur Lake, we walk along a new levee that they pushed up with a bulldozer to keep water in the lake longer so that fish can lay eggs once again. The levee is pocked with young saplings of peepal and native bamboo. Looking down into the lowland, I can see the small islands they built and planted with trees to serve as nesting sites for birds.

At another spot just off of Mahabs Highway is a dock where you can rent paddle boats to explore Muttukadu Backwater, south of Pallikaranai. Dozens of pelicans sit on the water, bobbing on its calm surface. Here and in other neighborhoods near the ocean, excessive groundwater use has allowed seawater to push in, turning aquifers salty. Muttukadu has grown too salty for some of its native fish, and water levels have dropped. In response, Care Earth Trust has begun educating local people, petitioning the government to regulate water extraction, and restoring pathways to allow fresh water to flow into the wetland and replenish it. They’ve also started replanting mangroves to improve breeding habitat for fish.

To be continued next week…

Erica Gies is an independent journalist who covers science and the environment from Victoria, British Columbia, and San Francisco, California. Her work appears in the New York Times, Scientific American, Nature, Ensia, The Economist, bioGraphic, National Geographic, and other outlets.

Photographs by Dhritiman Mukherjee.

This story originally appeared in bioGraphic, an online magazine about nature and sustainability powered by the California Academy of Sciences.

Chennai Ran Out of Water: Part 1

India Currents, in collaboration with bioGraphic and the California Academy of Sciences, is publishing a 3 part series on Chennai’s relationship with water. To reduce flooding and bridge droughts, India’s southern coastal metropolis is using ancient knowledge, community action, and wetlands restoration to better harness its monsoon rains.

Half the story

From a minivan on the shoulder of Old Mahabalipuram Road on the south side of Chennai, hemmed in by honking trucks and autorickshaws, we watch a painted stork (Mycteria leucocephala) move with studied dignity through the long grasses of Pallikaranai Marsh. With each step, knee flexing toward the rear, the webbed foot closes, then spreads open again to find purchase on the soft land. As it tips toward a fish, striped white-and-black tail feathers spread, flashing a surprising red whoosh. Nearby an endangered spot-billed pelican (Pelecanus philippensis) swirls in for a landing, green-backed herons (Butorides striata) fish, and gray-headed swamphens (Porphyrio poliocephalus) tend to young among cattails and sedges—just a few of the 349 species of flora and fauna found here. We are watching from the vehicle because, with the traffic hurtling by, it’s not safe to get out. It’s a claustrophobic feeling—for myself, but more so for this delicate ecosystem. Just across the marsh, not far away, a network of power lines, buildings, and roads stretch beyond view.

In the last 50 years, this marsh has been literally decimated, losing 90 percent of its area to malls, restaurants, hotels, hospitals, and information technology firms. It’s part of a global problem. Over the past three centuries, 85 percent of the world’s marshes, sloughs, swamps, fens, and bogs have been drained, filled in, and built or planted upon. The relatively new IT corridor here is an echo of California’s Silicon Valley, where Google and Facebook squat on filled-in marsh. Over the past few decades, Chennai has sprawled into India’s fourth-largest city, from 48 square kilometers (18.5 square miles) in 1980 to more than 426 square kilometers (165 square miles) today.

And that development has not just harmed Pallikaranai Marsh. The natural landscape on which Chennai was built is particularly rich in water. Pallikaranai is linked hydrologically with a complex system of rivers, backwaters, coastal estuaries, mangrove forests, and ancient human-built lakes in a mosaic of movement—freshwater, brackish, salt—that once covered 186 square kilometers (72 square miles). But an assessment by a local NGO, Care Earth Trust, found that Chennai lost 62 percent of its wetlands between 1980 and 2010. That destruction has depleted habitat for wildlife and spawned dueling water problems for the people of Chennai.

In summer 2019, Chennai grabbed international headlines when it ran out of water. Government trucks made deliveries to roadside tanks, where people queued with vessels and occasionally brawled, resulting in at least one death. When I visited in mid-November, water trucks still plied the streets. But 2019 wasn’t an anomaly. Over the past two decades, Chennai has regularly run out of water during summer months. That’s because paved surfaces throughout the city prevent rain from being absorbed and replenishing groundwater that could be used during the dry season, says Balaji Narasimhan, a professor of engineering who specializes in hydrology at the Indian Institute of Technology Madras. The simple fact is, Chennai shouldn’t be running out of water at all. During its few months of monsoon, the city actually receives 1.5 times more rainfall than it consumes annually. But today’s water managers do their best to rush rain away in stormwater drains and canals, moving it rapidly out to sea. When they need water later, they turn to dwindling groundwater, distant supplies, and desalination plants.

During monsoon rains, water often floods vast swaths of the city. Among Chennai residents, more emotionally and politically jarring than routine water scarcity was the 2015 flood that killed at least 470 people, displaced hundreds of thousands, and left many stranded in their homes for weeks. Ironically, it was likely the local mindset of water scarcity that made the flood more deadly. As writer Krupa Ge documents in her book about the flood, Rivers Remember, reservoir managers were reluctant to release stored water ahead of the monsoon rains; when they finally recognized the threat, they discharged too much, too fast.

In addition to poorly planned development, climate change is also exacerbating these water swings. The city has seen increasingly frequent and intense cycles of both flooding and drought over the past two decades. As moderate rain fell early last December and streets began to flood, one local aptly captured Chennai’s dysfunctional relationship with water in a tweet: “till last week, the residents were booking water tankers and from today they will book rescue boats. What a city!”

These bifurcated water disasters are all the more tragic because early Tamil people, whose cultural and linguistic heritage continues proudly in today’s residents, developed an elegant system for capturing the precipitation that fell during monsoons, saving it for the dry season. Their method also replenished groundwater and minimized erosion from heavy rains. And it supported rather than devastated wetland habitats. 

Back to the future?

Beneath the peepal (Ficus religiosa) and tamarind (Tamarindus indica) trees, amongst the flower stalls and idli restaurants, greater Chennai’s 11 million people go about their business as cows and dogs wander and nap at will, and jungle crows (Corvus culminatus), Oriental magpie-robins (Copsychus saularis), and dragonflies swirl above the fray. Chennai is more chill than the northern megalopolises Delhi and Mumbai, but it shares that quintessentially Indian sheen of chaos that, upon longer observation, reveals an innate order. An unspoken dialogue of push and pull among countless beings following their individual paths somehow manages to keep the whole in a constant state of flow.

Image of Oriental Magpie in Chennai by Dhritiman Mukherjee.

Non-human lives, though, have less and less space to exist across India, where 1.4 billion—with a “b”—people jostle to survive and thrive in a land area one-third the size of the United States. Even so, solutions to this inherent tension don’t have to be an either/or. Reclaiming some of the ancient ways, restoring flow paths and space for water on the land, could provide greater water resiliency for humans and other organisms alike. Today a loose team of people in government, academia, and NGOs are working toward that vision.

The 2015 flood forced the city to acknowledge that poor development planning played a role in amplifying its water disasters. The Dutch office of International Water Affairs advised officials on flood recovery, underscoring that message. The following year, it offered them the opportunity to participate in a multi-year design and development program, called Water as Leverage, in partnership with local water experts and communities. Together they produced two reports that linked existing projects and laid out new ones that would conserve and restore natural and human-built water systems across the entire watershed. The aim was to harness nature, because protecting and restoring natural ecosystems and organisms is a way to also provide resources that people need. 

This concept is part of a “slow water” movement that’s beginning to take hold around the world. Generally speaking, modern humans have forgotten that water’s true nature is to flex with the rhythms of the earth, expanding and retreating in an eternal dance upon the land. In our many attempts to control nature, we’ve sped up water, channeled it, and rushed it away. We’ve forgotten the fact that when we give water a chance to linger on the landscape, floods are softened, water is stored, and natural systems are sustained. Champions of the slow water movement think that the key to greater resilience, particularly in the face of climate change, is a kind of de-engineering that reclaims space for water to pause on land, supporting natural and human-made communities. 

Although it may seem like an unimaginable challenge to restore space for water within a densely inhabited city, many experts think it’s possible. It requires thinking differently. Unlike standard gray infrastructure—dams, levees, stormwater tanks—slow water approaches typically involve many small projects scattered across a landscape that each absorb and hold some water. This dispersed approach is similar to the way that solar panels on every house can add up to a significant amount of electricity generation. 

That any natural water arteries still remain in Chennai is thanks in significant part to Jayshree Vencatesan, a 50-something biologist who founded the NGO Care Earth Trust in 2001 to protect Pallikaranai Marsh and other bodies of water around Chennai. When she began, “people said it was the stupidest thing anyone could do,” she says. “But if people challenge me, saying you cannot do a bit of work, I will take it up.” Based on her years of accumulated knowledge, in 2014 Vencatesan documented the cascading system of 61 wetlands and ancient human-built water bodies across the watershed that drain into Pallikaranai and later juxtaposed them with time-series maps showing what’s been lost. Catalyzing public awareness, her findings were the basis for a ruling by the Honorable High Court of Madras to prohibit further encroachment on wetlands by development, and to implement a state plan to restore some of these ecosystems.

Vencatesan and Care Earth Trust have been heavily involved with the Dutch-local Water as Leverage initiative. Initially, she says, “the government was amused” by the groups’ presentations, given the officials’ general bias in favor of the more typical development approaches of desalination plants, dikes, and filling in wetlands to “reclaim” land. But “when they looked at the final proposal, they were taken by … the in-depth understanding about the city and its hydrology,” she says. This initiative, the court ruling, and other recent events have put the city on course for change. “Until now, nature has been treated in Chennai as an externality, never factored into urban planning.” As this revolutionary shift takes shape, she predicts that sand dunes, marshes and other wetlands, and remnant patches of dry forest will once again become “the natural buffers to the city’s shocks.”

To be continued next week…

Erica Gies is an independent journalist who covers science and the environment from Victoria, British Columbia, and San Francisco, California. Her work appears in the New York Times, Scientific American, Nature, Ensia, The Economist, bioGraphic, National Geographic, and other outlets.

Photographs by Dhritiman Mukherjee.

This story originally appeared in bioGraphic, an online magazine about nature and sustainability powered by the California Academy of Sciences.