Conservation group International Rivers (IR) on Monday released a statement condemning the data used by the Mekong River Commission (MRC) in assessing Laos’ proposed 912-megawatt Pak Beng dam, claiming the figures were “insufficient and outdated”.

The controversial hydropower dam has been criticised for potential environmental impacts, especially in Cambodia’s Tonle Sap basin.

Experts commissioned by IR found that the documents included data from studies conducted in 2011, were based on limited sampling and did not take into account the cumulative effects of all dams on the Mekong.

“The review concludes that the Pak Beng Dam project documents . . . are insufficient to meaningfully evaluate the project’s environmental and social impacts,” a summary of the report reads.

The MRC secretariat responded by acknowledging its limitations, but said it was doing the best it could.

“MRC acknowledge[s] that the technical review of Pak Beng has been limited . . . hence assessments cannot be made with full confidence.

While information was imperfect, we believe the consultation process was the platform for stakeholders to raise their concerns,” a representative said via email.

The secretariat reiterated that the MRC cannot veto projects.Te Navuth, secretary-general of Cambodia’s National Mekong Committee, said he still has concerns.

“We are asking for more study on the effect of the combination of operations . . . we worry about the upcoming projects,” he said.