Update | Chinese dams blamed for exacerbating Southeast Asian drought

As China opened one of its six dams on the upper Mekong River last month to help parched Southeast Asian countries down river cope with a record drought, it was hailed as benevolent water diplomacy.

But to critics of hydroelectric dams built on the Mekong over the concerns of governments and activists, it was the self-serving act of a country that, along with hydropower-exporting Laos, has helped worsen the region’s water and environmental problems.

Much of Southeast Asia is suffering its worst drought in 20 or more years. Tens of millions of people in the region are affected by the low level of the Mekong, a rice-bowl-sustaining river system that flows into Laos, Thailand, Cambodia and Vietnam. Fresh water is running short for hundreds of thousands of people in Vietnam and Cambodia, and reduced water for irrigation has hurt agriculture, particularly rice growing in Thailand, where land under cultivation is being cut significantly this year.

Vietnam estimates that 400,000 hectares have been affected by saltwater intrusion, with some 166,000 hectares rendered infertile. The affected land accounts for nearly 10 per cent of the country’s paddy cultivation area in the Mekong Delta, its main rice-growing region.

The water level in the Tonle Sap river as it passes the royal palace in Cambodia’s capital, Phnom Penh, has fallen to a 50-year low.