Poor construction methods, with soil used in place of concrete, are now being blamed for a fatal hydropower dam collapse last year in Laos in what has been called the country's worst flooding in decades.

The disaster occurred on July 23, 2018 when a saddle dam at the Xe Pian Xe Namnoy (PNPC) hydropower project collapsed following heavy rains, inundating 12 villages and killing at least 40 people in Champassak and Attapeu provinces, leaving many more missing.

A report sent to the Lao government in March, but still not released to the public, reveals that "construction of the saddle dam was substandard," a PNPC official told RFA's Lao Service this week.

"It was built with soil," the official said, speaking on condition of anonymity. "That was the cause of the collapse. It couldn't handle that massive amount of water."

A new saddle dam, saddle dam D, is now under construction at a location a little more than a kilometer away from the dam that failed, the official said, adding that the new 400-meter-long structure will be built with concrete and anchored at a depth of at least 10 meters into the ground.

The team investigating the cause of the July 2018 disaster has recommended that all other saddle dams at the hydropower site also be built with concrete, he said.

Talks with South Korea

Also speaking to RFA, Singphet Bounsavattiphanh-vice chairman of the Lao government inspection agency-confirmed that the government had received the report and its recommendations in March.

"But they cannot publish it right now because they are in the process of negotiating with the South Korean government about what information should or should not be released to the public," he said.

PNPC is a consortium formed by a local Lao company and South Korea's SK Engineering & Construction, and Korean involvement in the project had earlier prompted Seoul to send relief teams to Laos to help mitigate the effects of the disaster.

The Lao government is expected to officially publish the investigation's results when talks with South Korea are concluded, Singphet said.

All findings of the report should be released as quickly as possible, though, Premredee Daohuang of the Thailand-based NGO Laos Dam Investigation Monitor said, also speaking to RFA.

"This is so the public can verify the information and raise questions," he said, adding, "This information shouldn't be known only to the Lao and South Korean governments."

In the wake of the Xe Pian Xe Namnoy disaster, Laos has stepped up scrutiny of an ambitious hydropower dam building program under which it aims to serve as the "battery of Asia" and sell hydropower to its more industrialized neighbors China, Thailand and others.

Reported and translated by Max Avary for RFA's Lao Service. Written in English by Richard Finney.

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