The controversial Don Sahong hydropower dam, which Laos says it will soon build just a kilometre from the Cambodian border, will not have significant effects on the Mekong River, according to an environmental impact assessment paid for by the dam’s builder.

Obtained yesterday, the report – prepared for Malaysian developer Mega First Corporation Berhad – says the project will actually benefit Laos, despite widespread concerns from environment groups.

“[The dam] will not have significant local or cumulative impacts on the Mekong River flows, fish migration, or fisheries,” the document says.

The EIA, submitted in January, adds that only 11 households will be relocated to make way for the project, which may have “small but positive impacts on global climate change by providing electricity that does not involve the burning of fossil fuels”.

“The health risks facing people living in the Lao PDR are higher than for those living elsewhere in the region …the hydropower project can improve this situation.”

The EIA was prepared by the National Consulting Company, which is based in the Lao capital, Vientiane, following an earlier EIA in 2007.

Laos, which has committed to building hydropower projects on the Mekong in the face of opposition from environment groups and its neighbours, pressed ahead with building the 1,285-megawatt Xayaburi dam last November.

A number of Lao ministries, including the prime minister’s office, were involved in the environmental assessment process, the Don Sahong EIA says.

Environment group International Rivers has warned that the dam “spells disaster for Mekong fish” and threatens the survival of the already endangered Irrawaddy dolphin.

Adding to these concerns, Meach Mean, a coordinator at the 3S Rivers Protection Network, said yesterday that the EIA had not considered Cambodians living downstream.

“It just focuses on the Laos side and the company that is investing . . . the communities downstream here, we have had not any consultation,” he said. “It will have a huge effect on fisheries, especially during the dry season.”