Villagers living downstream from the controversial Lower Sesan II hydropower project have claimed that they contracted unusual skin ailments causing large black spots on their bodies after the firm building the dam drained industrial waste into a river they use for bathing.

Cambodia’s Royal Group, a major shareholder in the Hydro Lower Sesan 2 Company, which is building the dam, has denied the connection.

Locals in Plok village, only a few kilometres downstream from the $800-million project in Stung Treng province’s Sesan district, have said they saw workers at the dam site using explosives near the river bank and piping industrial waste into the water earlier this year.

“When villagers went in the water a few times when it got hotter and the water receded in May and June, they became itchy.

We do not know the cause yet, but we think that it might be caused by the dam construction,” said Thor Mai, 49, an ethnic Lao village representative.

He added that about half of the village’s 900 locals had come down with the same condition.

“I saw a few pipes used for draining the cement water into the river. Some workers drilled and exploded the stone a lot there. That might be the reason,” Mai said.

Mai said he also began to suffer from the same condition, but recovered almost two weeks ago after visiting a doctor, who prescribed medication.

“The itchy disease caused many black spots all over the body and it is very, very itchy. It makes us sleepless and unable to eat properly.

Some people still suffer from this disease since they keep using the water from the river,” Mai said, adding that he now only uses water from streams, wells and paddy fields.

“My villagers are not healthy like before and no medical officials have inspected the outbreak yet.”

Um Bun Reth, a representative of the Royal Group, denied that the company’s activities had affected the people’s health.

“The construction work has not affected the river water and the location of stone processing is about 3 to 4 kilometres from the river,” he said.

He added that the river had been diverted at the dam site to an old canal which runs parallel to the usual route of the Sesan river, and that the company had now asked medical professionals to assess the villagers’ health.

Luch Seng Eang of the provincial Health Department said it had received reports of the outbreak and was dispatching medical officials to conduct inspections.

Meach Mean, coordinator of the 3S Rivers Protection Network, which campaigns on behalf of those affected by the project, said that he had heard about the condition as long ago as last year.

“The people suspect that the construction of the Lower Sesan II Hydroelectric Dam is the cause since the liquid waste from the construction site was dumped into the river via plastic pipes.

Fishermen contracted this disease as well.”