Under pressure

Known to the people who live along its banks as the "mother of all rivers," the Mekong provides food, water and work for some 60 million people who live along its shores.

It flows from the mountains of Tibet through Burma, Laos, Thailand and Cambodia before opening into the Mekong Delta and ultimately the South China Sea off Vietnam.

It's also home to over 1,000 species of fish, including the world's 10 largest fresh water fish, making it second only to the Amazon in terms of biodiversity, according to Avia Imhoff of the International River Network.

"It's still one of the last great rivers of the world that is still in a mostly natural state," Imhoff said. "The diversity of species is still largely intact and the whole ecosystem is intact because there have been so few river interventions until now in the basin."

A cycle of life

The cycle of high and low water levels that delivers nutrients for farmers' fields and fish for locals' diets is part of the reason the region has been able to remain intact. People have grown accustomed to water levels that can rise by up to 15 meters (nearly 50 feet) during the rainy season, says Eric Baran of the Worldfish Center.

"They expect a flood every year because the flood rejuvenates the agriculture and the productivity and brings fish and water," Banan said. "It is really a beneficial event."

Some 2 percent of the all the world's fish catches come from the Mekong system, making it largest source of fish after the planet's oceans.

The 1.5 million tons of pulled from the river annually are worth about a billion dollars. They also account for most of the protein in locals' diets, according to So Nam, deputy director of the Cambodian Fisheries Administration.

A growing burden

There are signs that people are already fishing too much.

"What's clear is that fish sizes and catches are decreasing, while the effort to catch them has inceased," said Martin Geiger, freshwater expert at the World Wide Fund for Nature (WWF).

The region's rapidly expanding population troubles environmental protection groups. By 2025 they expect some 90 million people to be living along the Mekong. That's a 50 percent increase within 15 years. More people and rising affluence is also expected to generate more demand for energy, making dams along the Mekong an increasingly attractive investment.

There are already plans for 11 hydroelectric plants along the lower Mekong, including seven in Laos alone. Four power plants currently exist on the Chinese portion of the river.

Dams pose an enormous problem for fish populations. Two-thirds of the species in the Mekong travel great distances to spawn and the number of planned dams would prevent many fish from being able to use 'ladders' or other detours, according to Geiger.

"Dams would lead to the collapse of the valuable fish biodiversity as well as the supply of protein to people," he said.

Poor to bear the brunt

The region's poor would be hardest hit by a drop in protein supplies as they are least likely to be able to afford fish from aquaculture.

Setting up fish farms would also represent another major interference in the region's ecosystem. They take over wetlands and conditions often pollute waterways and breed disease.

"What research has suggested - that people breed rabbits or concentrate on alternative forms of income and protein supply - will be difficult," Geiger said. "It would require land and it would require investment and, of course, the know-how to do it."

No stopping progress

The Mekong River Commission (MRC), founded by Laos, Thailand, Cambodia and Vietnam, is aware of the threats to the Mekong's resources and works to promote cooperation along the river.

In November, it is expected to give its verdict on the environmental impact of one of the dams that Laos seems determined to press ahead with: the Xayaburi.

There are no guarantees that Laos will respect its decision. The Commission is concerned that dams would prevent mineral and nutrient-rich sediment from flowing downriver into the "rice bowl of Vietnam" - a region that produces more than 16 tons of rice a year.

Laos argues that hydroelectric power will have fewer detrimental effects on the region than other sources of energy.

It aims to become "the battery" of Southeast Asia by eventually building 10 dams on the Mekong. It doesn't need the energy for itself. It intends to export it and has signed contracts with Thailand for up to 95 percent of the energy expected to be generated from its projects.

Sharp criticism from Cambodia, Thailand and Vietnam has led Laos to reevaluate the environmental effects the dams could have. But politicians and environmental protection groups say they realize developing economies will not put off development indefinitely.

"For us it is not about preventing all hydroelectric power dams," Geiger said. "In cooperation with the Mekong River Commission, we want to keep dams off the Mekong's main arm for the next 10 years. Until we know what the real effects will be on the population's protein supply and food security."

China holds all the cards

China's absence from the Mekong River Commission, however, makes it difficult for the organization to decide on the best dam locations. Beijing has substantial plans to develop the region. It intends to deepen the river to make commercial shipping easier and to expand on the four power plants it already has on the Mekong.

Kelly Brooks from Oxfam says that, ultimately, China's location means it holds all the cards.

"China has a strategic geographic position," she said. "With China being upstream to all of the countries in the MRC they have the position where they can control the flow of the water."

As a transnational institution, it's up to the Mekong River Commission to come up with ways of balancing members' interests in using the river for industrial purposes and protecting the ecosystem. But that's no easy task.

"Because the region here has a history of conflicts and there are still many, many sensitive issues just below the surface," the Mekong River Commission's Joern Kristensen said. "Unless this situation is managed well, it could turn into a problem."

Author: Alexander Freund

Editor: Nathan Witkop