CHAY ARENG RIVER, Cambodia: Along the Chay Areng Valley in the remote Cardamom Mountains of Cambodia, children still scamper barefoot through one of the last remaining tracts of virgin jungle in mainland Southeast Asia.
If they take the same paths in a few years, they will probably have to be swimming.
Faced with a rapidly growing but power-starved economy, Prime Minister Hun Sen has decided that the rivers flowing from one of the few elevated spots in a relentlessly flat country should become a source of energy.
In the past two years he has agreed to at least four Chinese-financed hydropower projects as part of a $3 billion plan to raise the country's electricity output from just 300 megawatts today to 1,000 in a decade, enough to power a small city.
The indigenous communities in the forests in the Cardamoms appear to be the ones that will pay the biggest price.
"We have been living here without a dam for many generations; we don't want to see our ancestral lands stolen," 78-year-old Sok Nuon said, lighting a fire inside her wooden hut nestled among trees near the Chay Areng River.
"I do not want to move, as it takes years for fruit trees to produce crops," she said. "By then, I'll be dead."
Few people argue that Cambodia's 14 million people do not need more power.
After decades of war and upheaval, including the Khmer Rouge "killing fields" of the 1970s, the economy has finally taken off, growing at a rate of nearly 10 percent a year.
But its antiquated power plants, fueled mostly by diesel fuel, can meet only 75 percent of demand, meaning frequent blackouts and prices around twice those in neighboring Thailand and Vietnam. Those factors inhibit faster economic expansion.
With the closer ties Hun Sen has cultivated with Beijing over the past five years, Chinese cash and dam-building expertise has become a solution to the pains of breakneck growth.
"Chinese investment in hydropower is so important for Cambodia's development," Foreign Minister Hor Namhong said in January after meeting with his Chinese counterpart, Yang Jiechi.
But critics maintain that much of the planning is taking place with scant regard for the long-term impact on the environment in a country where most people still rely on agriculture for their livelihoods.
"Poorly conceived and developed hydropower projects could needlessly and irreparably damage Cambodia's river system with serious consequences," said Carl Middleton of the U.S.-based group International Rivers Network.
But the Chay Areng project hardly appears to be a model of transparency. The deal was signed in late 2006 with China Southern Power Grid, one of the two electricity network operators in China, to build a 260-megawatt plant at an estimated cost of $200 million, with a completion date of 2015.
The first that villagers knew of the project was when Chinese engineers turned up this year to start working on feasibility studies. Officials at Southern Grid and in the Cambodian government have been reluctant to discuss the details of the studies.
The Chinese Embassy in Phnom Penh denied any shortcuts were being taken in the dam construction.
"They comply with environmental standards and are approved by the Cambodian government," said a Chinese diplomat who was granted anonymity because of the political sensitivity surrounding the project. "We just want to help Cambodia as much as we can."
Environmentalists who have conducted their own studies say the reservoir created by the dam will cover 110 square kilometers, or 42 square miles, and displace thousands of indigenous people in nine villages.
More than 200 animal species, including elephants, sun bears, leopards and the endangered Siamese crocodile, would be affected upstream, said Sam Chanthy of the NGO Forum on Cambodia, a foreign-financed group in Phnom Penh.
Downstream from the site, the delicate ecosystem of the flooded forest, home to some of the world's rarest turtle species as well as hundreds of types of migratory fish, would also be at risk from disruptions to water flow, Chanthy said.
Eng Polo, who works for the wildlife group Conservation International, agreed. "It won't take long for these invaluable assets to disappear when the dam is built," he said.