Multinational consulting and engineering firm Pöyry has signed a contract with the Lao government to supervise construction of the divisive Xayaburi hydropower dam in the country’s north, it announced Friday.

Pöyry, which is under investigation by the Finnish government for its role in previous consulting on the dam, will work as the Lao government’s engineer on the project, which officially began last Wednesday.

This work, carried out by its Energy Business Group, will include reviewing the design and supervising construction.

“The design includes multiple fish passages, fish-friendly turbines, low-level outlet gates for sediment flushing and navigation locks for shipping to minimise possible adverse environmental and social effects,” a company statement says.

Energy Business Group president Ari Asikainen said Pöyry would monitor construction and compliance with Mekong River Commission guidelines.

Laos announced a week ago that it was building the dam, the first of its kind on the lower Mekong River, in defiance of the governments of Cambodia and Vietnam and environmental groups that fear it will have negative effects on the river and millions living downstream.

Senior Lao ministers have said a study carried out by Pöyry in 2011 recommended how to improve the project, but environmental groups such as International Rivers have criticised the study for not addressing the concerns of other countries.

The Finnish government said late last month it would investigate Pöyry over allegations it violated Finland’s responsible business standards and Organisation for Economic Cooperation and Development guidelines by consulting on the project when Cambodia and Vietnam opposed it.

Meanwhile, a Thai Senate subcommittee last week criticised its government for backing the Xayaburi project.

Thailand, which will receive 90 per cent of the dam’s electricity, was risking the safety of its people and its reputation by backing the project, the Subcommittee on Water, Marine and Coastal Resources said in a statement released on Thursday, urging the Thai government to revoke its power purchase agreement.

To contact the reporter on this story: Shane Worrell at [email protected]