Muan Onkaew is only 45. But as she flashes a black smile, standing barefoot at the doorway of her stilt house, she appears much older.
Mega First Corporation Berhad claims the dam poses no threat to local fishers.
Years of chewing betel nuts are probably largely to blame, but the homemade net dangling under her home gives another clue to her worn air.
For the inhabitants of Ban Don Sahong village in Khong district, where Mrs Muan has lived for 10 years, fishing is an increasingly precarious livelihood.
She and her husband often come home empty handed, she said.
Not that the Mekong has completely withdrawn its bounty. In the high season of June and July, the villagers still haul giants from its depths.
"Some are even bigger than a motorcycle," she said.
But a hydropower project planned for the Hou Sahong channel that runs by her house could now extinguish all hope of better catches.
Environmentalists, including International Rivers, warn that its dam could block fish migrations. No proven measures exist for protecting fish stocks, they warn.
In response to such concerns, the village head has canvassed the views of his community.
For villagers like Mrs Muan, though, the project can trigger conflicted responses.
Viraphonh: Playing down concerns
Many hope the dam could bring relative prosperity to a community that, like 20% of Laos households, still lies outside the power grid.
By 2020, the government aims to cut that figure to less than 10%. Already, 14 electricity projects, all hydropower, are delivering a total of 3.2GW _ although only 1GW serves Laos' 6.6 million inhabitants, while the flows to Thailand.
The Don Sahong dam is part of a government plan to fully exploit 20GW of hydro potential, of which Laos would export 85%.
As one of the villagers who still relies on lanterns, 54-year-old Pon Wongkamchan supports the project, which he hopes will bring jobs as well as electricity.
"Ten years ago, we used to earn 200,000 baht (US$6,300) per year from selling fish, but now we get only half of that," he said.
"We've been doing the same thing for generations, and we want something else."
In fact, a social impact assessment by Laos-based National Consulting Company suggests the villagers' incomes are far lower, averaging only $600 per year, mainly from fishing but also from stockbreeding and agriculture.
Nui Nakraison, 67, who has lived in Ban Don Sahong since he was born, gives a similar account of dwindling catches, although he blames rising population rather than environmental issues.
The government has promised to help residents with measures such as an irrigation system so farming can continue in the dry season, he added.
But for Mega First Corporation Berhad, the company developing the Don Sahong project, the dam poses no additional threat to local fishers.
Of the Mekong's seven major channels, only Hou Sadam is free of waterfalls and serious rapids, said Peter Hawkins, a senior environmental manager at Mega First.
"If ships can come, fish can definitely come," he said.
The company, while holds 80% in the $600 million project, has undertaken to improve migration pathways along this channel, where illegal traps currently take a heavy toll on fish stocks, he said.
"The biggest myth is that adverse impacts on fish migration can't be mitigated," said Dr Hawkins.
But the Laotian government, which holds 20% in the project, is already aiming to persuade residents that fishing cannot offer a sustainable lifestyle.
Viraphonh Viravong, Laos' Vice Minister of Energy and Mines, plays down international concerns as overlooking the project's benefits.
For locals, all government projects create a win-win situation, he said.
Residents would work on the project and benefit from new roads and improved education, healthcare, electrification and water supply, he said.
"The pressure on fishing is too much, and the fish population is going down because we aren't fishing in a sustainable way," says Mr Viraphon.
Ban Don Sahong is one of six villages affected by the construction of the dam, and 11 households will have to be relocated.
Under a resettlement action plan submitted by National Consulting, Mega First must pay a total of $385,600 to compensate all the affected families.
But for Witoon Permpongsacharoen, director of the Mekong Energy and Ecology Network's Foundation for Ecological Recovery, the 260MW dam cannot justify the disruption.
"To put it straight, this dam won't be able to power three shopping malls in Bangkok," he said.
A run-of-river dam, with limited energy storage, operates only three to four hours per day, he said.
In his view, the main driver for the project is not electricity demand but business, overriding public welfare.
The government gains from hydro projects through royalties, taxes and dividends, and is looking into coal and lignite, he added.
What's more, the project has been pushed through autocratically, ignoring expert opinion, he claimed.
If all goes to plan, by early next year, all contracts for the dam should be finalised, so construction can get underway in April or May.
The first unit is set to operate by the start of 2018, said Mr Viraphonh.
"But it will be more than a year before we start touching the river, and hopefully by then we can convince people that fish are very clever," he said.
For villagers like Muan Onkaew the project can trigger conflicting responses.