A world receding

The Economist

The changes brought by China's dams

THE scent of woodsmoke from Mr Guo’s cast-iron stove hangs heavy in the brisk evening air. The household generator is switched off for the night, and the low kitchen in which his family and two guests gather is made cozy by the light of kerosene lamps. His wife brings a succession of bowls to the table: steamed rice, chunks cut from a salted pig’s leg that hangs above the stove, lettuce braised with garlic, scraps of beef sautéed with chilies, and tsampa, a roast barley powder favoured by his ethnically Tibetan family. His mother-in-law serves a medicinal-tasting infusion made from local leaves and berries, as well as eggshell cups of local wine. The wine tastes as though it was made by someone who knew only two things about wine: it is supposed to be red, and it is supposed to get you drunk.

French missionaries brought grapes and the Gospel to Yunnan in the late 19th century; wine has been made in Cizhong ever since. They left a more enduring monument too: a sombre stone church with a charmingly incongruous Tibetan-style roof that sweeps skyward at its edges. A priest from Inner Mongolia holds masses there for ethnic-Tibetan Catholics. Cizhong spreads out from the church like the bottom half of a Chagall painting: donkeys wander the stone streets; ramshackle houses squat along alleyways; vineyards and rice paddies frame the view.

But that is about to change. A little way downriver, a state-owned power utility is building the 990-megawatt Wunonglong dam. In 1995 the Manwan dam, some 600km farther downstream, became the first to stem the river’s flow. Since then five more dams have been finished along its Chinese reach; the Wunonglong dam is one of a further 14 being planned or built there.

China’s Communist Party has long been keen on dams. At least 86,000 have been built over the past six decades, providing 282 gigawatts (GW) of installed hydroelectric capacity by 2014. The government is building yet more to curb the country’s greenhouse-gas emissions. By 2020 it wants an astonishing 350GW of installed hydropower capacity; in the European Union that would be enough to meet about three-quarters of total electricity needs. The dam at Wunonglong, about 300 metres long and more than 100 metres high, will provide a smidgen less than one of those extra gigawatts. The other 13 are expected to add 15.1GW more.

Downriver countries intend to build another 11 large dams on the Mekong, with dozens more planned for its tributaries. In 20 years the Mekong could well be dammed from Tibet to just above Phnom Penh, where the delta begins. In no other large river basin in the world is the planned rate of growth of hydropower as great.

The dams will change the quality of the water in the river and the rate at which it flows. Some of this change could be for the better. Dams can prevent flooding by regulating the flow of water downstream. But some Mekong riverbank agriculture would not welcome too steady a flow. 

Increasing water in the dry season would shrink riverbeds, leaving less space for crops—millions of Mekong-basin dwellers grow vegetables on riverbanks. Reducing water in the rainy season produces smaller floodplains with less sediment deposited in them, impoverishing the soil.

According to International Rivers, an environmental NGO, the full cascade of dams planned for the Lancang would trap nearly all of the sediment coming from China, cutting the water’s sediment load in half. That will be bad for soils and bad for fish; the sediments provide the river’s nutrients. And the dams lower down could worsen the problem; the clear, “hungry” water that flows from them in spates will carry away existing sediment in riverbanks and riverbeds. Some of that will be deposited farther still downstream; some will wash uselessly out to sea.

Those lower dams will also make things yet harder for the nutrient-deprived fish. The 11 proposed in Laos and Cambodia could block the migration of around 70% of the Mekong’s commercial fish catch. Interfering with the fish’s feeding and reproduction to that extent would imperil the food security of populations across the lower Mekong basin, where the average person eats some 60kg of freshwater fish per year, more than 18 times what is on the menu in Europe or America. Considering how poor many of the people here are, replacing fish as a primary protein source is virtually impossible.

Dams restrict the movement of fish; they force movement on people. Along the road leading out of Cizhong, past the dormitories housing the construction workers for the Wunonglong dam, He Zhenghai, a friend of Mr Guo, points to a denuded spot where a village used to be. A few kilometres farther on he points out the resettlement: rows of squat, charmless concrete structures plonked down along the side of the road, near nothing.

Estimates by NGOs of the total number of Chinese people resettled because of dam projects exceed 20m. Dams on the Lancang have already added thousands more, mostly poor rural farmers, to the total. In 2013 the compensation received on relocation was about 80,000 yuan ($12,500). Some farmers complain that they have been resettled on sheer hillsides ill-suited to farming and, to add insult to injury, chronically short of water.

The Wunonglong dam will inundate Yanmen, a nearby village whose residents will be resettled on Cizhong’s rice paddies. And this means that, in a way, Cizhong, too, will vanish. Brian Eyler, deputy director of the South-East Asia programme at the Stimson Centre, an American think-tank, says Yanmen sits above Cizhong in China’s administrative league tables, meaning that after resettlement Cizhong will be renamed Yanmen, losing its name along with much of its charm.

The vanishing 4,000

Making Laos a battery

AT HUAY XAI on the Thailand-Laos border, around 1,000km downriver from Mr Guo’s house in Cizhong, a sampan’s tubercular engine kicks in with a wheeze, a gag and a violent sneeze of black smoke. As the motor stammers a tiny conductor terrorises the boat, calling brusquely for tickets, chastising people for where and how they sit, shouting at the pilot to get a move on. As the boat pulls away she jumps off, smoking and yelling the whole time. Some of the locals immediately set about the business of napping, using rice sacks as pillows. Others spread bolts of fabric to picnic on, pulling out plastic bags of grilled chicken, sticky rice, bamboo shoots and tiny, floral South-East Asian oranges. The tourists, meanwhile, open cans of beer—except for the Brits, who open bottles of rotgut Thai whiskey. Tourists and locals alike start the journey staring at their phones. Eventually reception wanes and they are forced to gaze out at the wonder on all sides.

By the time it reaches Huay Xai the Mekong has already run more than the entire length of the Rhine and descended more than 3,000 metres—handily more than the Rhine manages. It still has almost two Rhine-lengths to go—but along that journey it will only drop a further 400 metres. It is a lowland river now, lush and steady. The evening chill of Mr Guo’s kitchen has been replaced by ripe, vaguely fetid South-East Asian warmth.

About two hours into the two-day journey east from Huay Xai to Luang Prabang, the boat pulls over to a muddy shore, distinguished only by a concrete staircase cut into the side of a mountain. As the boat approaches people suddenly appear out of the jungle at the top of the stairs. The scene repeats itself with minor variations throughout the journey: a muddy path rather than a staircase, a rickety little jetty or two. A couple of hours before the boat pulls in to regally sleepy Luang Prabang, it passes the Pak Ou caves: two caverns in a mountainside from which hundreds of Buddha statues brought by devotees stare down at passing boats.

Just downstream from Luang Prabang, the $3.5 billion, 1.3GW Xayaburi dam is rising—one of nine this country of 6.8m mostly rural, mostly poor people plans for the Mekong mainstream. Laos wants hydropower to be its main source of revenue by 2025: it plans to sell its capacity to neighbouring countries. The Thai government has agreed to buy 95% of Xayaburi’s power. Six Thai banks have financed the dam and a Thai construction firm is building it.

Laos’s downstream neighbours are far less enthusiastic. Cambodia (two dams of its own planned) and Vietnam (no suitable sites for dams at all), worried about the impacts that the Xayaburi dam will have on fisheries and water flow, have lodged objections with the Mekong River Commission that was set up by Cambodia, Laos, Thailand and Vietnam in 1995. The MRC is meant to facilitate co-operation among the countries that share the watershed; China and Myanmar have the status of “dialogue partners”.

Environmental groups warn that by turning a free-flowing river into a series of reservoirs the upstream Lao dams could wipe out the Mekong’s two largest freshwater species: the giant catfish and the giant pangasius. Similar warnings have been raised about the Don Sahong dam—which would span the Mekong across the breathtakingly beautiful Si Phan Don (Four Thousand Islands) region near Laos’s border with Cambodia—and about Cambodia’s giant Sambor dam, which may destroy one of the last remaining habitats of the Irrawaddy dolphin.

The Xayaburi dam’s builders have redesigned its sluice gates to allow more nutrient-rich sediment to flow downstream, and widened its fish pass to accommodate more fish of different species. The Lao government says these tweaks will alleviate the worst harms. Environmentalists are less certain. Fish passes in dams have been repeatedly found not to live up to promises made for them, particularly when fish must pass through multiple sets, as they would if Laos builds all its planned dams.

The Mekong might survive a few big mainstream dams, but a dozen—plus dozens more on its tributaries—present a qualitatively different sort of threat. This highlights a recurring theme of Mekong development: dam-builders tend to assess the impact of each dam individually; NGOs pay more attention to the cumulative effect of multiple dams. The NGOs also worry that with every new dam built, further dam-building becomes more normal, and the next project thus becomes easier to justify.

Environmentalists think both that such synergies make the harm done by dams greater than governments claim, and that the benefits are overestimated. Touting hydropower as “green” because it can be used in the place of fossil-fuel derived electricity overlooks external costs such as compensation and relocation, lost agricultural productivity and biodiversity and lowered water quality. And although benefits may be large (especially for electricity exporters), they are hardly overwhelming, especially in the context of broader development. Power demand in the region is expected to more than double between now and 2025—having already doubled from 2005. 

According to Richard Cronin, a Mekong specialist at the Stimson Centre, an American think-tank, the nine Lao and two Cambodian dams currently discussed would provide just 6-8% of the total electricity needs of the lower Mekong basin by 2030, with most of the power going to Thailand. “For that,” Mr Cronin asks, “you’re going to kill the river?”

Pressure from downstream countries and international NGOs has slowed Laos’s progress on its next two dams, the Don Sahong and the Pak Beng, and has forced developers to spend more money studying potential downstream harms. But Laos is a poor country with few natural resources that sees hydropower as its route to development. In the absence of better options, concerned citizens and the governments of the downstream neighbours may be able to do little more than delay Laos.

For now the Mekong remains blissfully unobstructed as it passes from Laos into Cambodia—except for the bloom of tiny islands that give Si Phan Don its name. People live on just a few of these islands. Some cater to tourists happy to spend a few days rafting the occasional rapids and listening to the Mekong rush past. But many are little more than a clump of rock and mud on which sprays of rivergrass and shrubs have taken root, still green against flowing brown. Past the waterfalls roiling the water into spume the river relaxes again. On clear days it becomes a hazy mirror, the stark blue above turning to indistinct brightness below.

Fathers and sons

How fisheries can fade

CHANG NAA stands up on the prow of his narrow wooden canoe and casts a small net into the water under the watchful eyes of his son Chang Thung, a four-year-old as solid and sombre as his father is lithe and placid. Beneath the canoe’s tattered fabric roof his wife stirs a pot of samlaa macchu, a sour soup. Before serving it she rinses the dishes in the murky water.

The Tonle Sap river is a two-way tributary which joins the Mekong about 800km downriver from Xayaburi, at Phnom Penh. In drier seasons it drains South-East Asia’s biggest freshwater lake, also called the Tonle Sap, into the Mekong; during the monsoon it flows the other way, bringing water and sediment from the Mekong to the lake. Mr Chang Naa and his family live in one of the river’s floating villages. He is 33 years old; he has been fishing the Tonle Sap for 15 years. His father fishes these same waters. In time, says Mr Chang Naa, so will Chang Thung: “With us, what the father does, the son will also do.”

Mainly he catches what he calls chkok and onpun—small, silvery fish. Some are destined for his wife’s soup pot. The rest—he catches between two and three kilos per day—he sells for prahok and tuk trey, a chunky paste and clear brown liquid both made from salted, fermented fish. Some fishermen supplement their meagre income with rice farming, but Mr Chang Naa and his family own no land. Like most people he knows, he is working off a perpetual debt incurred by money borrowed at extortionate rates for food, fuel and equipment. A fisherman from a village near Mr Chang Naa’s says he spends four or five months a year paying off local moneylenders.

The Tonle Sap lake yields around 300,000 tonnes of fish a year, accounting for most of Cambodia’s freshwater catch. In all, the MRC estimates that the Mekong yields around 2.6m tonnes of wild fish each year, worth at least $2 billion in dockside sales. Add in secondary industries such as fish processing, markets, fuel and equipment sales and boat building, and the total value of the Mekong’s fisheries is between $5.6 billion and $9.4 billion.

Small-scale fishing predominates along the Mekong—most boats in Cambodia weigh less than five tonnes and use engines with less than ten horsepower. Mr Chang Naa’s livelihood is not that different from his father’s or the vast majority of his peers. But that is starting to change with the rise in aquaculture. Production in the fish farms of Vietnam’s delta is now larger than that from its other freshwater and seawater fisheries combined. Prices for wild-caught fish are rising—Khai Ratana, who fishes a little way upriver from Mr Chang Naa, says he gets 12,000 riel ($3) per kilo, up from 3,000 riel five years ago—but that is because they have grown scarcer in recent years.

At this point in the river’s descent to the sea, its potential as a power generator has been used up. The lowest lying of the dams under discussion, Cambodia’s dam at Sambor, lies around 300km upriver. Cambodia’s fisheries thus illustrate the fundamental political tension at the heart of the region’s development: upstream economies overwhelmingly reap the benefits of changes to the river’s regime, while those downstream bear the cost.

This is the way with all rivers, but all the more so with the Mekong, because the geographical hierarchy reflects the geopolitical one. China, the most powerful nation, has the high ground and the most hydropower potential. It is also least dependent on the river’s water for other purposes (though it has plans to divert some of it away to its thirsty east anyway), the least susceptible to civil-society pressure and the least interested in binding itself to an international order.

This worries everyone downstream. China and Thailand have long enjoyed good relations, and China has bought goodwill in Laos and Cambodia with massive infrastructure investments. But Myanmar has opened up to the West in the past five years in part to counterbalance Chinese influence. Vietnam fears its powerful northern neighbour—China invaded as recently as 1979, and the two countries contest territory in the South China Sea—and anti-China sentiment has been rising in Laos. As China has grown more regionally assertive, Laos and Vietnam have sought to deepen their relations with America. Yet that will probably do very little to dissuade China from building more dams, any more than the objections of Laos’s vastly richer and more populous neighbour Vietnam deterred it from building its dam at Xayaburi.

These tensions will be kept in check by the general desire for a commodity quite as valuable as water: peace. For a long time it was in short supply, with decades of war, political division and the spiralling horrors of the Khmers Rouges perversely protecting the Mekong from exploitation. Nobody wanted to put up the capital for a dam that would be bombed, nationalised or left to rack and ruin. Those days are over; none would wish them back. The problem is managing equitably, and without permanent environmental degradation, the prosperity peace brings.

A hundred kilometres or so south-east of Mr Chang Naa’s fishing grounds, tourists in Phnom Penh sip mojitos in front of cafés as an endless parade of late-model sedans and smoke-spitting tuk-tuks jostles for space along Sisowath Quay. It is Cambodia’s one big, bustling city, with a sleazy edge to its tattered colonial elegance. Away from the river tens of thousands live in crowded slums—mainly rural Cambodians yearning for a bit of urban prosperity. Chang Naa expects his son, Chang Thung, to fish in his footsteps; he may want it so. But like all sons Chang Thung will step into a different river—or perhaps, in this case, onto a different shore. Phnom Penh was a city of just 189,000 in 1980. It could be home to 2.5m by 2030, and Chang Thung may choose to be one of them. His choice may be a free one. People in backwaters, both figurative and literal, choose cities all the time. But it may not be. By the time he reaches working age, the fears of dam sceptics may have been realised. There may be no more fish for him to catch.

The delta

A river stills, the seas rise

FIVE waitresses work the busy rooftop bar, ferrying drinks to the bright young things of Can Tho, the Mekong delta’s biggest city. Melodic, minor-key Vietnamese pop blares from the speakers as smartly turned-out young men and women sip lurid drinks, their faces lit by their phones. In the early evening the Hau river, a broad Mekong distributary, has taken on the same blue-grey cast as the sky, reflecting rows of quayside lamps as it flows into the distance, reaching for the sea.

Can Tho has the feel of a minor boomtown: scooters still outnumber motorcycles which still outnumber cars; there is plenty of commerce but few chain stores; tourists remain rare enough that a wedding party will invite a passing foreigner to eat, drink and toast with them. It is a gentler, friendlier place than Phnom Penh, but with an underlying sadness that one does not feel further upstream: Phnom Penh will grow more crowded and unmanageable in the coming decades; Can Tho may vanish.

To drive the four hours from Phnom Penh to Can Tho is to witness an increasingly blurry line between land and water. Narrow, glittering streams bisect rice fields. Rills, canals and other waterways flow deep into lush jungle, while the river itself wanders lazily toward the sea. Cambodians like to remind visitors that much of this delta region was theirs before the French partitioned the territory in 1949. The Vietnamese dispute this. The delta’s fertile soil has long been worth arguing over—or fighting for.

The famous floating markets of the delta are a little way south of Can Tho; their products abound on the city’s streets. Older women preside over rainbow mounds of dragonfruit, pomelo, durian and jackfruit, while young men tend grills of muddy-tasting snakehead fish. Of the Mekong delta’s 18.6m people, about a fifth of Vietnam’s population, more than three-quarters work in agriculture; on its roughly 4m irrigated hectares, the average farm size is just 1.2 hectares. From only 12% of Vietnam’s surface area the region provides most of the country’s fish and fruit, as well as half its rice; farmers can get seven crops in two years. Dang Kieu Nhan, a researcher at Can Tho university, points to an old Vietnamese saying: “If you want to make a good living, go to the Mekong delta: it’s hard to be hungry there.”

The worry is that some of what the region enjoyed in the past may now be beyond purchase. Few places in the world are as threatened by climate change as the Mekong delta. A brief stroll around Can Tho already leaves you coated in sweat, and the city is set to grow much sweatier. Average temperatures in Can Tho rose by 0.5ºC between 1979 and 2009. Vietnam’s natural-resources ministry predicts that temperatures will rise by a further 1.1-3.6ºC by 2100. It also expects more severe storms, wetter wet seasons and drier dry ones; all those effects, it says, will be greatest in the south.

Though rice thrives in wet, warm climates, it cannot stand too much of either. Rice fails when submerged underwater for long periods. Flooded fields can also hinder planting, and therefore harvesting. Rice yields may decline by an average of 10% for every 1ºC rise in average night-time temperatures. A changing climate may also lead to a flourishing of weeds and pests in rice fields.

Rising sea levels threaten not just the crops, but also the fields themselves. A report from the International Centre for Environmental Management, a consultancy, projects a 28-33cm rise in Vietnam’s seas by 2050, and 65-100cm by 2100—levels exacerbated, in the delta, by declining sediment flow from upstream. A sea-level rise of one metre could flood more than a quarter of the delta, and leave five million homeless. Can Tho is just 80cm above sea level.

The ocean could make farming impossible well before it finally swallows the land. Rising seas cause saline intrusion: seawater moving into places unaccustomed to it, such as wetlands and freshwater aquifers. Salt in a rice field can ruin the crops. Up to 70% of the delta’s agricultural land could be subject to saline intrusion this century. Some delta farmers have responded by switching from rice farming to aquaculture: shrimp, in particular, thrive in brackish water. But they fare poorly when the water gets as salty as the sea proper, meaning rising sea levels will eventually render shrimp farming just as impossible as rice farming.

Mangroves once provided a healthy buffer against both salinity intruding into the water table and the heavy winds that drive seawater inland, but population pressure and aquaculture have put paid to a lot of Vietnam’s mangrove forests. That leaves the delta reliant on dykes and hydraulics to mitigate saline intrusion, and these are expensive to build and maintain. Less intensive agriculture could relieve the stress on the delta, but Vietnam has a growing population to feed, and makes billions of dollars from exporting rice, fish, shrimp and fruit. Sediment carried downstream can help repair coastal erosion, but not if dams trap it in reservoirs. Mr Nhan mentions the prospect of shifting crops: cultivating rice and shrimp in the brackish lowlands, fruit and vegetables in the centre and high-value export rice in the upper delta. This makes sense—it may be the best that can be done until drought ruins the rice and rising seas reach the fruit.

For now the Mekong, which began as a trickle of snowmelt high up in Tibetan cloud-country, slices through riots of tropical green to meet the South China Sea in a network of river mouths known as the “nine dragon river delta” in what appears to be much the same way as it always has. Tourists who watch women haggling in floating markets over baskets of mangosteen and fresh fish, or who see peasants in conical hats farming paddies by hand, imagine that they are witnessing something timeless—life as it always has been, its rhythms dictated by seasons, land and sea. But though it seems they are witnessing a pastoral, what they are seeing is in fact the opening scene of a tragedy: the part where the characters act as they always have, but their fate looms large.

Eventually, all rivers empty into oceans; water comes together with other waters. But for this river, at this delta, the sense of an eternal return is lessened, that of an ending heightened. The seas, driven by a century of global industry, rise higher, while for the sake of a little more industrial power, the gifts of the river are being squandered. Life as it has been is not life as it will be. The days of stepping into the river are numbered.