The Environmental Concerns of Mekong River

The two most current issues facing the river are the building of dams and blasting of rapids.

A number of dams have already been built on the river's tributaries, notably the Pak Mun dam in Thailand. This has been criticised on grounds of cost as well as damage to the environment and to the livelihoods of affected villagers, though none have been built on the main part itself.

China is engaged in an extensive program of dam-building on the river itself: it has already completed three, the first called the Manwan dam, another twelve are under consideration.

Poverty stricken Cambodia is one nation that is completely dependent on the river for food and the vast majority of its fledgling economy. The annual floods provide much needed water for crops of the otherwise dry dusty land, and to refresh Tonle Sap, yet its major cities are all vulnerable to flooding. The Tonle Sap Biosphere Reserve has been created to try to protect areas around the Tonle Sap Lake and river, which is connected to the Mekong.

The Mekong River Commission, a panel of the region's nations, has accused China of blatantly disregarding the nations downstream in its plans to dam the river in an effort to stop the dams, but to no avail. Since the building of the first Chinese dam, many species have become endangered, including the Mekong Dolphin and dugong, water levels have dropped as ferries get stuck, fish caught are small and the catch is less than half of before the dam, the turnover at Chiang Rai port is less than one fourth of previous years, and crossings from Chiang Rai to isolated Luang Prabang have lengthened from 8 hours to 2 days due to inadequate water levels.

Despite all these problems, new dams planned will have significantly worse impact if carried out as planned. All nations downstream and the environment will suffer from added pollution (due to development and relatively lax regulation and enforcement in China compared to Thailand, poisoning the food supply from pesticide runoff and heavy industry, as well as promoting algal blooms from organophosphates from agriculture, as well as water hyacinth infestation), river blockage problems as fish cannot swim upstream to spawn, and potentially devastating very low water flow.

Other environmental concerns arise from increased water flow in some parts as China clears rocks and sandbars, blasts gorges, and slows water as it dams and floods other sections, and relocates indigenous peoples. Cambodia is by far the most exposed, depending on a fine balance of water flow, fearing scenarios of mass famine and devastating floods, the likes of which destroyed the Angkor kingdom 700 years ago. Laos' biggest cities all hug the Mekong as does Vietnam's largest city and financial hub, Ho Chi Minh City, which would be vulnerable mostly to low flow and pollution.