Hydroelectric dams along the Mekong River have interrupted the river’s flow, causing serious damage to the complex ecosystems and rich biodiversity on which millions of people in the Mekong basin rely for a living.
According to experts and people, this has threatened peoples ability to mitigate and adapt to the changing climate.
The last monsoon rains gave way to a cool north wind, signalling the start of the Mekong Region’s dry season. This is the season for villagers along the Mekong River’s border between Chiang Rai and Bokeo province in Laos to start harvesting “Gai,” or Mekong River algae.
Gai, a local delicacy and key source of nourishment, can only be gathered from December to April when the water is low and clear enough for the freshwater algae to thrive.
Local women on both sides of the Mekong assemble on sandy islets in the middle of the river as Gai begins to bloom in early December to pick the season’s first harvest.
Traditionally, women harvest gai while males fish. Women have been gathering gai in the Mekong River since childhood. Gai and river fish have been important to local people’s lives and livelihoods since prehistoric times.
Most residents are farmers who face an increasing danger of crop damage and revenue loss due to variable weather patterns.
The river’s abundant resources are critical in boosting local populations’ resistance to climate change, as they may rely on Mekong fish and gai for additional food and money.
Because dams have negatively influenced fish and other food sources, gai is currently the only natural resource that locals can reliably take from the river. River flow disruptions are now threatening the gai harvest.
During the dry season, the hydro dams cause the river’s water level to increase and fall fast. This slows the growth of gai and raises the risk of drowning for those who collect the algae from the rocks in the sandy riverbed where it flourishes.
Niwat Roykaew, founder of the Chiang Khong Conservation Group, told ThaiPBS, hydropower development has been advocated as a clean energy source that will assist Mekong countries in reducing their reliance on fossil fuels and improving energy stability.
However, he added that development comes at a high cost to the ecosystem and the livelihoods of the Mekong’s people.
“People living along the Mekong are now facing serious threats to their lives and livelihoods, as a river that used to provide them with essential resources is now being killed by hydropower dams.”
Hydropower projects, according to Niwat, are inflicting such significant changes to the Mekong River that it may soon lose its significance as the lifeblood of ecosystems and livelihoods throughout Southeast Asia.
“The fluctuating water level is the first major issue.” Dams do more than only raise water levels during the dry season, affecting the gai harvest.
They also cause water levels to drop during the rainy season, disrupting the breeding cycles of aquatic creatures in the river, typically travelling to the nearby wetlands to spawn in the floodwater,” he explained.
“Without this seasonal flood pulse, the Mekong River is dying, and a lot of fish species are quickly disappearing.”
He stressed that the dams’ ecological degradation directly impacts the daily lives of local people, who rely heavily on the resources given by the river ecology. These people are now facing food and financial insecurity, as well as a loss of ability to adapt to climate change.
Thai authorities, he claims, are worsening the situation.
“The impacts of hydropower dams can be vividly seen, but the Thai government is still going ahead with agreements to purchase energy from three hydropower dam projects – Pak Lay, Luang Prabang, and Pak Beng,” added the official.
“Hydropower is branded as cheap and clean energy, but its cheapness comes at a high cost to the Mekong River and environment and this cost is being paid by local people who are losing their livelihoods forever.”