Authorities at the five Nam Ou River Basin Hydropower project in Phongsaly Province issued a notice this week stating that the release of stored water on Saturday, led to the demise of a massive fish population in the area.
The notice clarified that the water needed to be released after being stored for eight years because, at 430 meters, current water levels were at dead storage, a capacity that is not sufficient to generate electricity.
Soon after, residents and officials in Phongsaly’s Somphanh District discovered a huge amount of dead fish in the river.
The operator of the dam said it was necessary to release the water in Phongsaly to Luang Prabang as part of flood prevention measures during the rainy season and electricity generation during the dry season.
Mr. Bounhieng Sensoulin, Deputy Mayor of Samphanh District, said to the Laotian Times via a phone call that the release of the water may have disturbed the fish ecosystem downstream as it was stored since 2015.
“The operator informed and warned the residents in the areas earlier about the water release last Saturday as the water levels in front and back of the dam were quite low,” said the district deputy mayor.
According to him, district authorities inspected the areas where dead fish weighing around 1.5 to 2 tons were found.
The hydropower operator confirmed to authorities that the strong tides of the released water caused the incident and that no chemicals were released into the river stream.
The Nam Ou River Basin Hydropower company will soon be cleaning and removing the dead fish from the site, said the notice. The company will also compensate the local fish species either by reinstating their population or by providing funds to locals to buy them. Additionally, it will organize a conference to discuss the plan to prevent such an incident from occurring in the future.
This year, mass deaths of fish were also reported in Houaphanh Province due to the release of toxic chemicals from the construction site of the Nam Sam 3 Dams Hydropower Plant, according to local authorities.