Partially submerged houses in Kerala, India last August.

Partially submerged houses in Kerala, India last August. REUTERS / Sivaram V


In India, Nature’s Power Overwhelms Engineered Wetlands

The picturesque Kerala backwaters in southern India, increasingly popular with tourists, form a network of engineered canals, lagoons, lakes, and rice paddies. But a fatal monsoon deluge has highlighted the global problem of how developed wetlands often lose their capacity to absorb major floods.

In India, they call the state of Kerala in the country’s far south “God’s own country.” That wasn’t how it felt last August, when monsoon floods devastated its densely populated low-lying coastal plain. Around 500 people drowned, in an area best known to outsiders for its placid backwaters, a network of brackish lakes, lagoons, and canals where growing numbers of Western tourists cruise the picturesque waterways aboard luxury houseboats.

Now that the floodwaters have abated, questions are being raised about whether the disaster was made worse by water engineering projects in the backwaters designed to feed the state’s population and attract tourists. Increasingly, Kerala residents are wondering if “God’s own country” is damned as well as dammed.

The floods came out of the Western Ghats. This chain of mountains down the west side of India is one of the country’s wettest places, drenched from June to September in monsoon. In early August, the rains there were exceptionally intense and unremitting. The rivers flowing from the mountains west toward the Arabian Sea dumped their water into the backwaters on a coastal plain that is largely below sea level.

Sixty-mile-long Lake Vembanad, at the heart of the backwaters, rose up and flooded surrounding wetlands and rice paddies, cities, and farming villages. A quarter-million people took refuge in 1,500 relief camps; 6,200 miles of roads and 115 square miles of farmland were damaged. Cochin International Airport was awash.

Many of the backwaters have been drained in the past century to create rice fields and make way for development.

Four months on, when I visited, the cleanup had been largely completed in many places. Often all that was left was the high-water mark on buildings. But in many of the hardest-hit poor rural communities, recovery had barely begun.

At Kannady, a small village in the Kuttanad wetland south of Lake Vembanad, the Red Cross had only arrived in early December to offer tents to people whose houses had been destroyed. I found people still living in broken tin shacks, and a brick house had been razed by the floodwaters. Close by, villagers were laboriously digging a drain across their rice fields to cleanse it of polluted water so they could plant a new crop.

Some villagers blamed the floods on the backwaters. After all, as Kannady village councillor Ambila Gose pointed out, the floodwaters had come up from the lake and across wetlands into their community. Maybe more drainage canals would keep the water away.

But the truth, say hydrologists, is the opposite. The problem is that many of the backwaters have been drained in the past century to create rice fields and make way for development. These land reclamation projects, in Kuttanad and elsewhere, took away the capacity of the backwaters to absorb floods. What the villagers need is more wetlands, not fewer.

Floodwaters inundated much of Kerala's low-lying coastal plain, including the village of Pandanad, pictured here.

Floodwaters inundated much of Kerala's low-lying coastal plain, including the village of Pandanad, pictured here. MANJUNATH KIRAN / AFP / GETTY IMAGES

“The flood is man-made,” said B Sreekumar of the Kottayam Nature Society, which is based near Kannady. The wetlands “used to hold flood water, but they have all been reclaimed. To reduce the flood risks, we should remove all the encroachments, by blocking the drains and reflooding the land.”

What has happened in Kerala has played out worldwide in the past century as wetlands have been drained, diked, and dammed for agricultural development and flood control. But from the Mississippi delta to the Sundarbans mangrove swamps of Bangladesh, from the Rhine to the Yangtze, the combination has brought more hydrological mayhem than control of nature.

The backwaters that dominate the narrow coastal plain of Kerala are a tourists’ delight. Millions come each year, some now to see locations featured in Arundhati Roy’s Booker prize-winning novel The God of Small Things. (Our boatman on Lake Vembanad claimed to have been brought up in the same village as Roy. It might even be true.)

But the backwaters are not what they once were. Many of the mangroves that once lined Lake Vembanad have been removed to make way for tourist lodges and to improve their views of the water. Half a century ago, newly independent India rushed to drain the rich wetland soils of the plain for growing rice, as part of a national drive to achieve local food self-sufficiency.

Whatever the ecological losses, engineers believed they had the complex hydrology of the backwaters under control.

Meanwhile, Dutch engineers brought their techniques of land reclamation to convert parts of Lake Vembanad itself into more than 1,000 drained polders for rice cultivation, each with stone walls surrounding drained land a meter or more below the level of the lake outside.

Urbanization grabbed the wetlands too. In Kochi, Kerala’s fastest-growing city and main port, a few scraps of mangrove on riverbanks remind visitors of its wetland past. On the edge of Thrissur, another fast-growing metropolis, real estate developers have just completed Sobha City, a large estate of apartment blocks, on land annexed from the Kole wetland. It is surrounded by reed beds swaying in the breeze.

What remains of the Kole wetland is still rich in wildlife. A recent bird survey found 250 species, according to local birder Manoj Karingamadathil. Many of them were at a patch of former paddy near Palakkad, where we saw a greater spotted eagle within seconds of arrival. A pair of hoopoes crossed the path. Marsh harriers and pelicans were feeding on fish.

Even so, much has gone. By the end of the 20th century, the size of Vembanad Lake had been halved to less than 70 square miles. With siltation reducing its depth in many places, the lake’s water-holding capacity has diminished by three-quarters. The Kuttanad wetland has declined by two-thirds.

Whatever the ecological losses, engineers believed they had the complex hydrology of the backwaters under control, with a network of dams and barriers. But that complacency was blown away by the August floods, says Ritesh Kumar, South Asia chief of Wetlands International, an environmental NGO. The system may be able to handle regular monsoon flows, but the engineering has resulted in the entire backwaters system losing its ability to absorb major floods.

A damaged house on the banks of Pamba River following Kerala's widespread flooding last August. A quarter-million people were forced to take refuge at relief camps during the floods.

A damaged house on the banks of Pamba River following Kerala's widespread flooding last August. A quarter-million people were forced to take refuge at relief camps during the floods. Atul Loke / Getty Images

One target of concern are the dams that barricade many of the rivers flowing from the Western Ghats into the backwaters. In August, even as the floods continued, hydrologists were pointing out that virtually all the dam reservoirs were full at the start of the flood. That left no room to absorb heavy rains coming downstream.

“Steps could have been taken to avoid the calamities downstream,” hydrologist E.J. James of Karunya University in Coimbatore, a former member of the Kerala Dam Safety Authority, told the Deccan Chronicle at the height of the flooding. “There were predictions about incessant rain and [the] water level was bound to increase.” As soon as the heavy rains were forecast, managers should have begun gradually emptying the reservoirs to create space.

Biswajit Mukhopadhyay, an Indian water engineer working for the U.S. engineering firm IEA, agrees. He told Reuters: “The release could have started earlier, so that… there would have been leftover capacities in the reservoirs to store the water.”

Instead, under instructions to keep their reservoirs as full as possible to maximize electricity generation, managers ended up making rushed releases at the height of the floods, just to save their structures from being broken by the force of water behind them. At the 453-foot-high Cheruthoni dam, part of the Idukki dam complex on Kerala’s biggest river, the Periyar, operators opened all five gates for the first time in its 40 years of operation. “The dams were never meant to be opened like that; it caused massive flooding downstream,” says Kumar. The swollen river gushed downstream and across the Kole wetland, inundating Cochin airport for several days. Thousands of people had to be evacuated.

“Areas where wetlands reclamation had been most significant were the ones to bear the severest impacts,” says one expert.

Some civil engineers have raised questions about how much difference opening the dam gates made to the extent of the floods. K.P. Sudheer of the Indian Institute of Technology Madras, in Chennai, calculated that emptying the dams earlier on the Periyar River would only have reduced peak discharges downstream by 21 percent. People in Kannady village question that, remembering clearly that their floods dramatically worsened only after the dam had been opened.

However, says Kumar, the local debate about the dams has diverted attention from the more fundamental issue: managing the floodwaters themselves. This was a once-in-a-century flood. But this time, when the water was finally released from the overloaded dams, it had nowhere to go. The lakes and wetlands that previously would have absorbed the flood had been diked and drained to make rice fields, industrial estates, tourist resorts, and cities.

“The areas where wetlands reclamation had been most significant were also the ones to bear the severest of the impacts,” said Kumar.

I saw this myself in the village of Pullu, southwest of Thrissur on the Manakkody River. The village is an island surrounded by rice fields created by reclaiming the Kole wetland. Villagers told their story of the floods. How the water came from rivers into their fields and then surged into the village, reaching shoulder-high in places. Some residents had to be rescued by helicopter. Many houses were wrecked, and meager possessions washed away. Villagers lost almost all their livestock, too. “We released the cattle when the flood came, and not many returned,” said villager Siva Dason.

A luxury houseboat moored along Lake Vembanad near the tourist town of Kumarakom in Kerala.

A luxury houseboat moored along Lake Vembanad near the tourist town of Kumarakom in Kerala. Fred Pearce / Yale e360

Four months later, they are still recovering. They have pumped the polluted floodwaters from their wells. The government provided grants for those rebuilding their homes. But first they had to eat. A man named Badirruddin, whose house had been destroyed, was out fishing in the river. And rice fields where farmers had lost one rice crop to the flood were already planted with the next.

But the truth is they were in a place that in past times would have been a natural wetland. The Kole wetland is recognized by the Ramsar Convention as an internationally important wetland. Except that, as the woman I met in the village office conceded, her ward was “70 percent paddy, and 30 percent built on.” There was no wetland, and if there was any Indian law or authority to protect it, she didn’t know about it.

I asked villagers if they thought that converting all the surrounding wetland into rice fields surrounded by dikes might have left them vulnerable when the water came. The village leader K. Parameswaran thought for a while. Perhaps other communities were guilty, he said. It sounded like obfuscation, but it was a fair point. No village can save itself alone. It was a collective failure – a tragedy of the hydrological commons.

The problem lay in attempting to turn large areas of natural wetland and river floodplain into dry land, said Kumar: “This whole coastal area is a floodplain. It is where the water goes; it is natural. We should not try to prevent it.”

The writer of this article received travel funding from Wetlands International.