Cambodian environmental groups yesterday stepped up their calls for the Don Sahong dam in Laos to be cancelled, after a visit to the site failed to convince them the hydropower project would not harm the Mekong River and the people who depend on it.

“We ask our government to consider how our people will be impacted by this dam and to work with the other three countries of the Lower Mekong to reconsider the 12 mainstream dams,” Youk Senglong, program manager at Fisheries Action Coalition Team said during a press conference yesterday.

Set to be built less than two kilometres north of the Laos-Cambodia border, the 260-megawatt Don Sahong has drawn ire from environmental advocates, who say it could spell disaster for the Mekong.

Laos this week hosted a second site visit aimed at winning over stakeholders, but the opponents were no less worried.

“The Lao government is talking politics, not science,” said Tek Vannara, executive director of the NGO Forum on Cambodia.

NGO Forum yesterday echoed conservation group World Wildlife Fund’s recent reports on the Don Sahong, which criticise Laos’s second hydropower project for lacking scientific evaluation of impacts on downstream countries and for threatening the already critically endangered Irrawaddy dolphin.

“The [project’s] consultant said he would try to make sure the two channels beside the project will work as alternative fish passages, but ‘try’ is not enough,” Vannara said. “Cambodians depend on the fish from the Hou Sahong channel, which the dam would block.”

Project developers have maintained the Hou Sahong is not the only channel through which fish can migrate upstream to spawn. But Vanarra recalled previous scientific studies that have predicted the adjacent channels are too narrow or too shallow and rocky.

Senglong said villagers relying on the fisheries didn’t believe the developer’s party line either, and starting on March 28, communities in Stung Treng, Kratie and Kampong Cham provinces will go on a three-day march against the Don Sahong and Xayaburi dams.

“The Cambodia government has a responsibility to their people – they need to take action against this project,” Vannara said.