Construction workers in the northern mountains raise families moving from one hydropower project to the next.
Repairman Dinh Duy Thuong watched his wife and co-worker plummet to her death after falling from 23-meter scaffolding at a hydropower site six months ago.
He's now raising two kids, 9 and 13, alone at the remote construction site in the near-wilderness of Son La, a remote northern province.
But like many workers at hydropower projects in the far north, despite the problems, 45-year-old Thuong says he's comfortable with his life and doesn't want to take on the risks associated with change.
"Work in the cities may pay well, but who knows what will happen in the future?" Thuong says. "I'm familiar with this life and I always have work.
"Here, at least I have a job to do every day... and my kids are learning to take care of themselves. I'm lucky."
Nguyen Huu Luong was raised on the Da River in the northern mountains while his parents worked at the Hoa Binh Hydropower Plant in the eponymous province.
When they retired and moved back to their hometown, Luong stayed in the mountains and studied drilling and demolition at the site's school for workers' children.
From 2000-2005 he worked outside the central city of Da Nang building the Hai Van Tunnel. But he soon returned to the Da River to work on the Son La Hydropower Plant, farther north and more remote than Hoa Binh.
The site's 5,000 workers come from all over the country and most have been moving from construction site to construction site for years.
Forty-two-year-old Vu Duc Thuan has spent half his life living at such construction sites: the Hoa Binh Hydropower Plant from 1979-1993, then the Ialy plant on the central highlands' SeSan River from 1993-2000 and then near the Hai Van Tunnel in Da Nang.
When work at the Son La Hydropower Plant started in 2005, his family moved from their home in Nam Dinh Province to live with him at the site. They've been there ever since.
The Da River Corporation, which is building the plant's dam, has put up housing for workers. Some of the homes are for new families formed between workers while others are for workers uniting with their spouses and children like Thuan.
Nguyen Duy Hoan, a Da River Corporation official who has lived at dozens of hydropower plant projects, had his children come to live with him recently as they want to follow in his footsteps.
Many parents bring their children with them and send them to the schools owned by the company to save money by not having to provide for two households.
Each worker can earn around VND3 million ($172) a month if they're able to find regular work.
Experienced workers like Thuan and Luong, who manage to earn even more money, try to keep their children away from the sites.
Thuan says the dust and noise from the job can be unhealthy. "I've been having problems with my eyes and ears for several years but that's inevitable for workers like me."
Luong and his wife have sent their child to live with grandparents in their hometown.
"Our child has a stable life there and doesn't have to move around with us all the time," Luong says.
"But then again, we can only be together for about a week or two each year."
Luong says the best site he worked at was the Hai Van Tunnel.
"Not because the work was easier than at a hydropower plant but because it was near the city and things were more comfortable.
But still, many workers in the highlands show little interest in moving to the cities despite the hardships.
Luong says he'll never leave the north's hydropower sites.
"It's my destiny," he says.
Worker Le Thi Thao had it hard working construction and raising her seven-year-old boy who was born paralyzed.
But after an accident on the site paralyzed her as well, her husband Tran Van Trong is now shouldering the burden alone.
The couple used to save VND5 million ($287) to bring their son to the hospital for treatment every three months, but they've been unable to save since Thao's accident nine months ago.
"What will come, will come," Thuong says. "I won't despair, I'll try as hard as I can every day."