The Mekong must run free!

| 14th December 2013
Khone-Phapheng Falls. Photo: hiroo yamagata via
Khone-Phapheng Falls. Photo: hiroo yamagata via
The Mekong is among Southeast Asia's greatest rivers, sustaining tens of millions from its abundant fisheries and its floodwaters which both irrigate and fertilise. But as Tom Fawthrop reports, Nature's bounty, and beauty, are at risk from a series of 11 dams.
The Don Sahong Dam will only push Cambodia and Vietnam closer to a food crisis. Have they forgotten that fish are our lifeline and the backbone of our economy?

Explorers, travellers and traders have long been enchanted by the magical vistas and extraordinary biodiversity of the Mekong flowing through six countries from the mountains of Tibet to the delta in Vietnam.

Approaching the Cambodian border in the Laos's southern region of Siphandone lie the spectacular Khone Falls - where the river becomes braided into channels, with a glorious panorama of spectacular waterfalls and swirling rapids.

These rapids create endless islets - the famous Four Thousand Islands that give Siphandone its name, set apart by a maze of narrow channels and rapids.

This uniquely beautiful and biodiverse habitat is just upstream of a colony of Irrawaddy dolphins that also draws many visitors - sustaining a growing eco-tourism industry which directly benefits local communities.

Abundant resources

The river provides the largest inland fisheries in the world, its 1,000 species of fish providing nutrition and food security for over 60 million people. These include the iconic Giant Catfish, the world's largest catfish species, which can reach more than 3 metres in length and weigh over 300kg.

A Mekong River Commission (MRC) consultant in a 1994 report described the Khone Falls as "an ecologically unique area, so rare in nature that every effort should be made to preserve all of Khone Falls from any development."

This eco-tourism paradise has all the credentials to qualify as a World Heritage site - with all the tourism benefits that designation would bring. It is also eligible to become an internationally designated Ramsar wetland.

The total value of fisheries, tourism and other benefits has  been estimated at $2-3 billion per year.

Khone Falls in the dry season. Photo: Tom Fawthrop.

Khone Falls in the dry season. Photo: Tom Fawthrop.

All sacrificed on the altar of hydropower

But the Malaysian hydropower company Mega First, backed by the Laos government, has an entirely different plan: to construct a huge hydroelectric dam project at Don Sahong only a few kilometres away.

The MRC, comprising Cambodia, Laos, Thailand and Vietnam as its member states, was set up to facilitate peaceful dialogue, cooperation and good governance of the Mekong and its precious resources. On 30th September Laos notified the MRC of its plan to begin construction of the 260 megawatt Don Sahong Dam in 2014. [See the International Rivers Network map.]

The Don Sahong Dam will only push Cambodia and Vietnam closer to a food crisis. Have they forgotten that fish are our lifeline and the backbone of our economy?

This dam is the second in a hydropower programme approved by the Laos government to build a cascade of 11 dams. The first dam at Xayaburi was launched in November 2012 in the face of fierce opposition from NGOs in three Mekong countries; from numerous scientists; and from two MRC states, Cambodia and Vietnam. It is currently under construction (photograph below).

The Xayaburi also provoked a fierce conflict inside the MRC which has lasted from 2011 until the present, with no sign of coming to an end. Thailand lined up with Laos in support of the dam while Cambodia and Vietnam cited the need for more scientific studies to be completed prior to construction.

Now the prospect of the Don Sahong dam has triggered a new flurry of opposition across the Mekong region. A coalition of 103 Thai NGOs, drawing support from eight Provinces bordering the Mekong, have demanded that the Thai government take immediate action to block the dam project.

One of its most immediate impacts would be on the Irawaddy dolphins. Changes to the hydrology of their habitat just below the Don Sahong dam could lead to the colony's extinction.

What about the fisheries?

Chhith Sam Ath, Executive Director of the Phnom Penh NGO Forum Cambodia warns: "The Don Sahong Dam will only push Cambodia and Vietnam closer to a food crisis. The project is next to Cambodia's border. Have they forgotten that fish are our lifeline and the backbone of our economy? Fish are central to our diet and our main source of protein,"

Mekong Giant Catfish, Photo: John Tom /

Mekong Giant Catfish, Photo: John Tom

Scientists are warning of grave consequences for food security in the region if fish migration is blocked by a dam across the Sahong channel. according to Dr Ian Baird, a Mekong specialist at the University Of Wisconsin Madison,

"The dam would cause serious nutritional problems throughout the Mekong Region. Decreasing availability of fish in the marketplace would lead to higher prices, reducing fish consumption, especially by poorer consumers."

The Hou Sahong channel is the only channel allowing migratory fish to bypass the Khone Falls and rapids, and continue their journey into Laotian waters. It is used by an estimated 80-90 percent of migratory fish entering Cambodia from Laos.

So to locate a dam precisely so as to block the only viable channel for large scale fish migration on this stretch of the Mekong appears - to say the least - perverse.

Jeremy Bird, former CEO of the MRC, stresses the imperative to safeguard the Mekong's fisheries. When considering building dams on the Mekong, he told me in 2011, "fisheries is the number one issue that has to be solved. And the onus for demonstrating that this can be solved rests with the owner of the project."

Problem? What problem?

But Mega First airily dismisses concerns that the dams threaten fisheries as "unfounded". The Malaysian company's senior environmental manager, Dr Peter Hawkins, claimed in the Vientiane Times that "environmental impacts can be mitigated by using other natural channels adjacent to the Hou Sahong.

International consultants Poyry Energy Asia, hired by the Laos government, agree. Its director Knut Sierotzki said that in addition to fish passage technology, which has been developed and tested in countries such as Norway and Switzerland, the dam would hopefully employ "fish-friendly" turbines, developed for use on dams in the US. The dam would also undertake "sediment flushing".

But UK fisheries expert Terry Warren, a consultant on the first Don Sahong dam EIA in 2007 warns:

"If these fish can complete this migration, it means Cambodian fisheries will continue to flourish. Stop a migration and within a few years everything will start to collapse and eventually cease to exist. I see disaster looming for the fisheries of Cambodia and southern Laos, if this project goes ahead."

Fisheries experts also doubt the possibility of using any other channel. They point out that fish ladder and fish pass technology has only been widely tested and practised in only in the cold climates of North America, Norway and Switzerland.

Can fish ladder technology be transferred?

And they believe the technologies cannot be simply transplanted to a totally different fish ecology and environment in tropical climes, owing to the far greater complexity and diversity of the ecosystems.

Dr Jian Hua-Meng, WWF's hydropower consultant, is astounded by the sweeping assumption that fish technology could be so readily imported to a tropical Asia. He told The Ecologist:

"Building a fish pass based on experiences of northern Europe Switzerland and transferring them to the Mekong is just not serious business: According to the developer this is a dam that is so benign that has so little impact or zero impact. This is nonsense. It is plain ridiculous."

Critics also say the fisheries studies are being rushed. A 2011 study by Northwest Fisheries Science Centre in Seattle concluded that it would take decades of research "to ensure that specialised fish passage facilities actually meet the needs of these diverse fisheries of the Mekong".

The Xayaburi dam site. Photo: Tom Fawthrop.

The Xayaburi dam site. Photo: Tom Fawthrop.

The approach adopted at the Xayaburi dam gives little cause for confidence. Eric Baran, a leading fisheries expert working with the World Fish centre in Phnom Penh, visited the dam site in 2012. He later said that fish mitigation has never been adapted to the huge fish diversity of any tropical river in Asia, and remains untested on the Mekong:

"There has never been a successful fish pass built for a dam the size of Xayaburi, anywhere in the tropics."

Yet Laotian vice Minister of Energy Viraponh Viravong insists: "The Xayburi dam is one of three or four dams that have rather insignificant impacts on the Mekong. We are very confident that the impacts if any will not be significant. We are very confident of that."

During the recent visit to the Xayaburi dam site, a Poyry senior project manager was perhaps a little too frank when he told a guest:"Whether the fish get across (the dam), you'll only see when it is built".

'Main stream dams' and the MRC prior consultation process

Laos, one of the poorest nations in the region, has long been encouraged by the World Bank to develop hydropower as its prime avenue for earning foreign exchange by supplying electricity to its energy hungry neighbours, especially Thailand.

Many rivers and tributaries have already been dammed. But the 1995 Mekong Treaty stipulates that any country building a dam on the main stream of the Mekong must either find agreement by consensus with the other 3 Mekong states, or seriously address their objections to the dam project before construction begins.

The Don Sahong dam appears certain to re-ignite the bitter divisions in the MRC that were set off by the Xayaburi dam. Laos surprised almost everyone with its declaration that Don Sahong was no longer a "mainstream Mekong dam";but only a "tributary" - and tributaries are not subject to the prior consultation process.

This would benefit the authoritarian Lao regime which would therefore escape serious scrutiny by the affected downstream countries and the public forums mandated by the MRC that would take place in other countries where opposition's voices and grassroots communities could be heard.

However neighbouring Cambodia, supported by Vietnam and even Thailand have rejected this bizarre claim. The Laos government may have to accept some scrutiny after all.

Meanwhile WWF's research shows that the dam presents a risk to the endangered Giant Catfish and 227 other fish species that inhabit the lower Mekong. In spite of this, Poyry Energy Asia have argued that the environmental impact studies for the dam should be carried out during the period of construction.

"This is not a responsible corporate player", WWF's Jian commented. "This technology is unproven and experimental. It is a very high risk. The developer wants all the stakeholders to follow him blindly with a leap of faith into an uncertain future with a very risky game of roulette on the Mekong with the livelihoods of 60 million people at stake."

Fisheries expert Terry Warren questions the wisdom of the Don Sahong dam, given its potential "to ruin an extremely important SE Asian fisheries and the livelihoods of thousands", and its relatively modest electrical output. As he asks: "Why risk it?"

The impact of a series of Mekong dams

And remember - we have so far examined the impacts of just two dams on the lower Mekong, each threatening devastating damage to fisheries, biodiversity, natural beauty and tourism. But for the Laos Government this is only the beginning of an 11-dam cascade.

There has so far taken place only a single major study on the potential loss of fisheries from the dams: the Strategic Environment Assessment of SEA, commissioned by the MRC and released in 2010.

The SEA concludes that the dams could inflict economic havoc on these two countries, and strongly recommends a moratorium on building all mainstream dams on the Mekong for at least 10 years in order to complete further research on dam impacts.

Meanwhile technological breakthroughs in renewable electricity, solar energy in particular, are undermining any economic rational for building the dams. Of course Laos has a legitimate need for electricity but this could be provided at much lower cost by solar power - located much closer to power demand in the major cities - as its cost continues to decline. 

All the MRC countries should respect the moratorium called for by the SEA report. Construction at Xayaburi should be halted while proper studies on its impacts are carried out. The entire Don Sahong project must be called off given the enormous costs it threatens to inflict, and the paucity of its benefits. And Laos must explore alternative, lower cost and lower impact power generation strategies.

The Mekong must run free!



Tom Fawthrop is a freelance journalist working in Southeast Asia.

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