Dams that have been built on the Mekong River’s tributaries in Laos are inadequately designed, causing an irregular water flow that damages river ecosystems, a Lao researcher who studies dams in the hydropower-driven country says.
The sudden changes in the volume of water flowing downstream have a negative impact on fish and other aquatic life, he told RFA's Lao service, speaking on condition of anonymity.
“The reservoir[s] [are] small and not able to store a large quantity of water. The release of water is not regular, which has an impact on the river[s’] ecosystems, on biodiversity,” he explained.
If a dam’s reservoir is too small, when there is a heavy rainfall, water must be released from the reservoir. The sudden release of water floods the area below the dam and causes a rapid change in river flow, he explained.
“The area downstream from the dam[s], is no longer the same. Sometimes there is the erosion of the riverbanks and a loss of aquatic life,” he said.
The researcher said his observations were based on his research on the Nam Lik, Nam Mang 3, and Nam Ngum 2 dams, hydropower projects built on rivers in the southern part of northern Laos.
Most of Laos’s dams have a similar design, rendering them unable to store large enough volumes of water, he said.
With plans to export most of the power from the dams to Thailand, Vietnam, Cambodia, or China, Laos has said it hopes to become the “battery” of Southeast Asia.
Less than half of Laos’s population has access to electricity, and the country has embraced hydropower as part of its poverty reduction plans.
As of the beginning of this year, Laos had 14 operational hydropower dams, 10 under construction, and 56 proposed or in planning stages, according to an online government report.
The most controversial one is the proposed Xayaburi dam which studies show could have a major impact on the regional environment and threaten food security.
Environmental groups have opposed the dam, saying it would block fish migration and sediment flow on the Lower Mekong, affecting the millions of people in Southeast Asia who rely on the river’s ecosystem for their food and livelihoods.
The Mekong River originates in China and flows through Burma, Laos, Thailand, Cambodia, and Vietnam.
Reported by Nontarat Phaicharoen for RFA’s Lao service. Translated by Somnet Inthapannha. Written in English by Rachel Vandenbrink.