Killing the Mekong dam by dam 

Down the ages the mighty Mekong has beguiled explorers and locals alike with its swirling rapids, rocky inlets and dotted islets. Currents, reefs and rocks have repeatedly thwarted attempts at smooth navigation since French colonial times.
But today the natural landscape and rich biodiversity of the region’s longest river are under serious threat from both commercial plans for rock-blasting and a cascade of hydro-dams, which would combine to transform a free-flowing river into a series of reservoirs linked by canalisation.
Marc Goichot, chief water resources expert for the World Wildlife Fund Mekong region, sums up the river’s acute crisis: “Today, water quality is degrading fast. The drought in 2015 was the worst on record, floods are more frequent, fish catches are declining and the entire riverbed and river bank are eroding. The Mekong delta is literally sinking and shrinking.”
The river is reeling under the impacts from two new dams under construction on the lower Mekong in Laos – the Xayaburi and the Don Sahong dams. And a Chinese project at Pak Beng in Laos will be launched by the end of this year, in addition to the seven existing dams upstream in China.
The rush to unleash an unregulated cascade of 11 dams on the lower Mekong is inflicting irreversible harm on the region’s most important river.
Water resources and river governance 
A recent WWF report sought to remind governments and the business sector that it is not only the ecology that will be destroyed. In the long-term there will be serious losses to the economy as well.  
“Economic growth in the Greater Mekong region depends on the Mekong River, but unsustainable and uncoordinated development is pushing the river system to the brink.”
Meanwhile a Finnish study reports that hydrology of the river has suffered major changes from Chinese dams. The annual flood pulse during the monsoon season has been seriously disrupted by reduced water flow.
Fisheries experts have warned that this will erode food security for the 60 million people living in the Mekong basin. 
The lack of good governance and riverine regulation has led to excessive sand-mining for the construction industry in China, Laos, Cambodia and Vietnam. This deprives the Mekong of essential sediment needed for the preservation of a healthy river.
These business decisions take place without any prior consultation with environmental agencies, local communities or any knowledge of the damage being done to the river. 
Stuart Orr, a co- author of the WWF report says: “Governments, companies and communities in the Mekong region must come together to develop joint solutions to water governance challenges”, instead of the current fragmentation of decision-making between the Mekong River countries, investors and planners.
At its inception in 1995, it was hoped that the Mekong River Commission (MRC) would achieve a spirit of cooperation for the common good of all stakeholders and protection of the river’s ecology. But its lack of regulatory powers, and lacklustre leadership has spurred a passive response to the fate of the region’s longest river, and over-exploitation for commercial development.
China’s grand plan to remove all obstacles to navigation – rocks reefs and rapids – has gained general approval from Thailand, without any prior study of the importance of the river’s biodiversity. Goods do not have to be transported by the waterway, since there are already viable alternative road routes while major rail lines through Laos and Thailand are in the pipeline. But wild birds, fish and other species that thrive on the islets of a free-flowing river have no alternatives. This biodiversity, once gone, is irreplaceable.
Mekong experts say that in order to forge a consensus on responsible business and more ethical investment, companies should be offered economic incentives with taxes and compliance offsets to foster integrated economic planning that is sensitive to environmental impacts, prior to any major investment decision being taken.
Current practice permits governments and investors to build a dam first and consider the environmental consequences later. 
In the case of the Xayaburi and Don Sahong dams in Laos, the decision on construction was taken prior to any consultation with riparian neighbours, resulting in a seriously weakened MRC-consultation process. The other Mekong stakeholders were merely invited to offer suggestions on how to limit the environmental damage – and denied any voice on the more substantive issue of whether the dam projects should go ahead or be stopped.
The fundamental flaw in this approach is the peremptory dismissal of the stand taken by millions of Mekong citizens living downstream in Cambodia, Vietnam and eight Thai provinces bordering the river, who did not believe the developers’ claim that construction would bring only minor impacts.
Most debate on the future of the Mekong has turned on such arguments as “trade-offs” between the ecology and the economy, based on an unproven assumption that environmental harm and fisheries can be easily mitigated.
Natural Mekong fisheries in the four MRC countries are worth a total $11 billion per year. If we incorporate fish farming, that figure increases to $17 billion. 
But can the world’s most valuable freshwater fisheries, on whom 60 million people depend for food security, survive the threats posed by the dams?
Dr Martin Mallen-Cooper, a fisheries specialist and research professor at Australia’s Charles Sturt University, is sceptical: “Assessment and mitigation of impacts are not a priority for developers of Mekong dams and impacts are often poorly understood.” 
He says there is no record of any successful application of fish mitigation on tropical rivers in Asia, Africa or South America in large rivers where the survival of hundreds of different species were at stake. 
Australian Mekong specialist at Sydney University, Dr Philip Hirsch, told this correspondent: “In 40 years of research, I have never seen a dam that has been successfully mitigated.”
The development pattern set for the Xayaburi dam, now under construction, is worrying. The decision to construct was taken by the Laos government and dam-builder Ch Karnchang prior to the MRC consultation process with other member states. 
The current state of the Mekong offers no support for the notion that, by adding the label “sustainable” to hydropower, you can magically render large dams as somehow “eco-friendly” or much less destructive.
Can development of the once mighty Mekong alter its currently blighted course of unregulated exploitation, and the alarming rate of depletion of its natural resources?
Developing renewable energy options that would protect the river would be a good start.
“One step is that before we build any more dams, new green energy technologies need to be explored,” argues Hirsch, a Professor of Human Geography.
“It would be a tragedy to see the world’s greatest inland fishery destroyed for lack of imagination in applying cost-effective innovative solutions.” 

Tom Fawthrop is a Mekong researcher and film-maker. He has directed two documentaries on the Mekong and also 
produced “Mega-dams on the Salween”.