As the water level in the Mekong River dips to a record 50-year low, a familiar pattern of fault-finding has risen to the surface. China, the regional giant through which parts of South-east Asia's largest waterway flows through, is again at the receiving end of verbal salvoes from its neighbours.
Environmentalists and sections of the regional media are blaming the Chinese dams being built or operating on the upper reaches of the Mekong for contributing to the dramatic drop in water levels that are affecting communities in Burma, Cambodia, Laos, Thailand and Vietnam, the lower Mekong countries.
"Changes to the Mekong River's daily hydrology and sediment load since the early 1990s have already been linked to the operation of the (Chinese) dam cascade by academics," states the Save the Mekong Coalition, a Bangkok-based network of activists and grassroots groups. "Communities downstream in northern Thailand, Burma and Laos have suffered loss of fish and aquatic plant resources impacting local economies and livelihoods."
Fishing is the main source of livelihood for the 60 million people living in the Mekong Basin, and the annual income from fisheries in the lower Mekong is between two to three billion U.S. dollars.
Newspapers in Thailand, which are freer and feistier than those in other countries across the region, have been more blunt. "China is fast failing the good-neighbour test in the current Mekong River crisis," argued the English- language daily "Bangkok Post" in a recent editorial. "The trouble is China's unilateral decision to harness the Mekong with eight hydroelectric dams."
Stung by this latest barrage of criticism, China has taken the unusual step of breaking its silence to mount its own defence, placing the blame for the drop in the Mekong River's levels to the unusually harsh drought across this region.
As part of this shift in diplomacy to engage with the lower Mekong countries, one of Beijing's envoys reminded critics that the water from China's portion of the Mekong, which it calls the Lancang, accounts for less than a fifth of the volume of water in the river.
Therefore, his argument goes, what China does upstream cannot have such a big impact on water levels downstream.
Beijing's attribution of low water levels to the drought, instead of its dams, has been endorsed by the Mekong River Commission (MRC), an inter- governmental body that manages the river basin. "At this point we have no direct evidence that the drop in water levels is caused by the Chinese dams," said Damian Kean, communications adviser to the MRC.
"If the dams are not contributing to loss of water level in the Mekong, then China should publicly release information of water level flows - said Carl Middleton the Mekong programme coordinator of International Rivers, to IPS News - The Chinese have not disclosed information about the operations of its dams on the Mekong, you need proper information and data to manage a river basin."
"The local communities along the river banks in northern Thailand believe that the change in the water levels began after the Chinese dams," says Montree Chantavong of Towards Ecological Recovery and Regional Alliance, a Bangkok-based environmental lobby. "It has impacted their fisheries activity."
China has already completed four of a cascade of eight dams, with the Xiaowan Dam, whose reservoir began harnessing the Mekong's waters in October 2009, being described as "the world's highest arch dam."
"Le comunitŠ rivierasche nel nord della Thailandia ritengono che il cambiamento del livello delle acque sia iniziato dopo la costruzione delle dighe cinesi, influenzando i livelli di pesca", sostiene Montree Chantavong, della Towards Ecological Recovery and Regional Alliance, una associazione ambientalist con sede a Bangkok.
La Cina ha giŠ completato quattro delle otto dighe previste. L'ultima _© la diga di Xiaowan, il cui bacino ha iniziato a sfruttare le acque del Mekong nell'ottobre 2009, viene descritta come diga ad arco pi__ alta del mondo.