Asean leaders have failed to respond to the plea of thousands of Mekong Delta residents urging them to forego plans to build a further 11 hydropower dams along the river, devastating livelihoods and endangered species, an NGO said yesterday. The petition with 23,110 signatories was delivered to leaders at the Asean People's Forum on Friday, along with written requests for further meetings to discuss the issue from the NGO coalition, Save the Mekong. But five member states - Myanmar, Cambodia, Laos, the Philippines and Singapore - did not send representatives to the meeting that connects civil rights groups and policymakers. 'These developments rendered the interface, an important space for civil society to engage with government officials, utterly meaningless,' a forum statement said. Save the Mekong had aimed to discuss the environmental impact of the 11 dams - two in Cambodia, seven in Laos and two in Thailand - through country representatives at the forum. The coalition says the dams will affect around 70 per cent of the total annual US$9.4 billion commercial fishing industry on the river by disrupting fish migratory patterns. 'These plans are inconsistent with the Asean charter, including commitments to protect the environment, to use natural resources sustainably and to preserve cultural heritage,' Dr Carl Middleton, Mekong Programme Co-ordinator of NGO International Rivers, a member of the coalition, said. 'Proposals to build dams on the Mekong River's mainstream epitomise an outdated development model that violates affected people's rights and fails to ensure sustainable development,' he added. The petition came via postcards, 15,282 of which were sent by residents of the Mekong Delta - 7,797 from Thailand, 3,805 from Vietnam, 2,682 from Cambodia, 616 from Laos, 352 from China, 30 from Myanmar - with the remaining 7,828 signatories from around the world. Cambodian fisheries administration director Nao Thuok said the dams would affect fish migration to some extent. 'We need to do a feasibility study; any dam has to have a study and environmental assessments.' The coalition said the building of mainstream dams would jeopardise regional food security, nutrition and health, seriously damaging initiatives aimed at alleviating poverty and meeting development targets. 'The planned dams for the mainstream Mekong River and its larger tributaries would have a devastating impact on the world's most important inland fisheries - those of the Mekong River Basin,' agreed Dr Ian Baird of the University of Victoria, Canada, a prominent scientist on the Mekong Delta. Asked whether there were any alternatives to hydropower for developing countries such as Cambodia, he added that that most of the dams' electricity would be exported.