Earlier this week, Zhang Guobao, China's top energy official, said that in order for China to achieve its clean energy development targets for 2020, it must start building more big hydropower projects.

At a time when much of the world is swearing off big dams because of their adverse environmental and social consequences, the announcement further exacerbates concerns about the future of the 5,400 kilometer-long Mekong River, where three dams are already in place, two more very large ones are being built and at least nine more are planned as China and countries on the lower reaches vy for the Mekong's water and the power it can produce.

When representatives from the Lower Mekong Basin – Vietnam, Laos, Cambodia, and host country Thailand – gathered in April for the first-ever Mekong River Commission summit, the river was its lowest level in two decades due to a prolonged drought. The Mekong, which flows through China, Burma, Vietnam, Laos, Cambodia and Thailand, and provides food, water, and transport for about 65 million people, is clearly in peril.

The river's future is also threatened due to a host of natural and man-made threats. Unless riparian states make a concerted, joint effort to manage its resources prudently and sustainably, their actions risk threatening food security, destroying livelihoods, and heightening regional tensions.

The main threat is from hydropower. China, which already has five operational dams, plans to construct about 15 more large to mega-sized hydropower dams upstream. Yet Beijing is not solely to blame. Southeast Asian states themselves are projected to build 11 of their own dams further downstream. These dams do not deplete the river's water supply per se, but they affect the hydrology of the Mekong by altering the natural timing and volume of its seasonal flows. According to a report by the Stimson Center, a Washington D.C.-based think tank, resulting reductions in silt deposits downstream could threaten one of the most productive regions of wet rice cultivation, while erratic water currents would threaten the spawning migration of fish in what is now the world's largest freshwater fishery.

Other future trends are equally, if not more worrying. Demographic and development pressures will exert additional pressure on already threatened resources. According to projections by the United Nations Environment Program, the population in the Lower Mekong is expected to swell to 90 million by 2025, with more than a third living in urban areas. Total irrigation water requirements for the region, which was about 43,700 million cubic meters in 2002, will rise to about 56,700 million cubic meters by the end of this year.

Disruptive climate change threats also hover in the longer-term. Global conservation group WWF predicts intense floods and droughts, coastal erosion, higher seas and heat waves for the Mekong Delta. Vietnam's own Ministry of Natural Resources and Environment says that if sea levels rise 30 inches by 2100, 20 percent of the Delta and 10 percent of Ho Chi Minh City could be swamped.

The six riparian states now seem to at least somewhat grasp the growing threats to and the coming crisis. At the first summit convened in the MRC's 15-year history in April, Thai Prime Minister and host Abhisit Vejjajiva declared that the Mekong "will not survive" if nations do not "take joint responsibility for its long term sustainability". Leaders of the four Mekong Basin nations – Thailand, Laos, Cambodia and Vietnam – also agreed on areas for "priority action", including researching climate-change-related threats and intensifying efforts toward flood and drought management. China, for its part, also began releasing previously withheld data on water flows in its section of the river last month in response to claims that its dams upstream were causing the current protracted drought.

Yet far bolder efforts are needed. China and Burma must become full members of the Mekong commission instead of just dialogue partners in order to truly participate. China may be right that its dams are not causing the current drought, but suspicions linger over Beijing's actions precisely because it has refused to share data with downstream nations or sign on to the 1995 Agreement on the Cooperation for the Sustainable Development of the Mekong River Basin. If China does not show signs of addressing other riparian states' concerns, the perception will remain, however accurate, that Beijing is just reaping the benefits of hydropower from its upstream location while Southeast Asian nations downstream are left to bear the environmental costs.

Vietnam, Cambodia, Thailand and Laos must themselves strike a better balance between their individual economic needs and environmental responsibilities. Government planning and decision-making reportedly takes place without adequate local input or comprehensive cost-benefit evaluations. In Cambodia and Laos, analysts complain that government officials lack the governance and human capacity necessary to conduct or comprehend research about the scale of potential environmental damage.

Commercial or geostrategic imperatives may also lead these governments to disregard knowledge even when it is available, since some dam proposals are linked to the wealthy Siphandone family in Southern Laos or the Chinese government, Cambodia's largest aid donor. Greater participatory planning and more detailed assessments must be conducted before decisions are made about mammoth infrastructure projects in order to accurately assess their implications and make plans to address the fallout from them.

Trans-boundary river management also ought to extend beyond research and contingency planning. Countries must consult each other about any major development projects they are undertaking as outlined in the 1995 agreement, since the Mekong is a shared resource. Riparian states should also try to agree on a basin-wide standard for environmental and socio-economic impact studies, as the Stimson Center report advocates. The Mekong River Commission should also broaden its cooperation with countries such as the United States, which could potentially assist Lower Mekong Basin states with human capacity building or research technology. The introduction of the Lower Mekong Initiative by US Secretary of State Hillary Clinton at the 2009 Asean ministerial meeting in Thailand, as well as the addition of a position on Mekong affairs to the staff of the State Department's East Asia/Pacific Bureau, means that there exists sufficient political will, interest and resources to engage Washington on this issue.

The threat to the Mekong should be clear to all by now. It is up to riparian nations, international organizations and other interested countries to cooperatively ensure that these grim scenarios and gloomy predictions do not crystallize into reality. Otherwise, as energy security concerns grow, one of the world's greatest rivers will be endangered, with profound implications for the region.

Prashanth Parameswaran is a research assistant at the Project 2049 Institute, a think tank in Washington, D.C. that covers Asian security issues.