Time for China to share Mekong data

Michael Richardson, For The Straits Times 29 Mar 10;

CHINA has a public relations problem over a series of dams it is building on the upper reaches of South-east Asia's longest river, the Mekong.

Its dams are being blamed in some quarters for worsening the impact of one of the worst droughts on record in the Mekong basin.

'China's dams killing Mekong,' blared an editorial in the Bangkok Post last month. It asserted that the dams on upper sections of the river, which China calls the Lancang, were having an adverse impact on millions of people, many of them poor farmers and fishermen, living downstream in South-east Asia.

Earlier this month, a coalition of non-governmental organisations claiming to represent affected communities in South-east Asia said the Chinese dams had been built 'without consultation, apology, disclosure of data, compensation or restitution, all of which are now long overdue'.

In the wake of this criticism, Thailand's Foreign Minister Kasit Piromya said China and South-east Asia should not quarrel but find ways to improve management of the Mekong. How Beijing handles the Mekong problem will affect its relations with the region, especially Thailand, Laos, Cambodia and Vietnam.

An indication of whether China is prepared to share more information with its neighbours will come this week at a conference being organised by the Mekong River Commission (MRC), the inter-governmental agency overseeing development of the river.

China and Myanmar are not MRC members. But as 'dialogue partners' since 1996, they have been invited to send high-level representatives to the summit in Thailand, which runs from Friday to Monday.

What are the facts? Much of northern Thailand, Laos, south-west China and parts of Cambodia and Vietnam are suffering from one of the most severe dry periods in recent history.

China's Yunnan province is among the worst hit areas. The Mekong dams are located in Yunnan mainly to generate electricity. Power is being rationed. Officials estimate that six million people are short of water and that crop losses will amount to at least US$1.5 billion (S$2.1 billion).

The MRC says its weather data shows that low water levels in the Mekong and its tributaries are the result of extreme natural conditions. Very low rainfall in the current dry season followed an unusually early end to last year's wet season. As a result, the river is at its lowest levels in at least 50 years.

However, this weather phenomenon coincides with a significant development in Chinese dam building. Last July, China began filling the reservoir of the Xiaowan Dam - one of the world's tallest dams and the fourth built in Yunnan on the Mekong mainstream.

In terms of water storage capacity, the first three Chinese dams on the Mekong, completed between 1992 and 2008, are relative minnows. Together, their reservoirs hold back just over 2.9 billion cubic metres of water.

The Xiaowan reservoir will hold 15 billion cubic metres of water, more than five times as much. Filling it is expected to take between five and 10 years, assuming that half the normal water flow is held back during this period.

Chinese officials point out that although 44 per cent of the 4,880km Mekong is in China, only 13.5 per cent of its average annual flow originates in China, far less than what comes from Laos, Cambodia and Thailand.

One of the questions China should answer is how much of the natural dry season flow is being held back, and how long will it take to fill the Xiaowan reservoir?

MRC chief executive officer Jeremy Bird says that in the next few years the completed storage capacity of the Chinese dams will lead to increased dry season flows downstream, with perhaps as much as 40 per cent more water reaching Vientiane on the Mekong in Laos.

However, he adds that for the time being the Chinese projects that have been completed are 'not sufficiently large to consistently deliver such benefits'.

China plans to have eight dams on the Mekong in Yunnan and may eventually build more higher up the river. By 2014, it is scheduled to complete another dam below the Xiaowan, at Nuozhadu. It will not be quite as high but will impound even more water, nearly 23 billion cubic metres. How long will it take to fill and how much of the Mekong's natural flow will be held back as it does so?

Eventually, the Chinese dams should have some positive impact. By retaining water in the wet season, they will help control flooding and river bank erosion downstream. Conversely, releases from hydropower reservoirs to generate electricity in the summer will help raise water levels in the lower Mekong in the dry season.

The best way of forestalling a recurring public relations problem with Southeast Asia would be for China to join the MRC and share river and dam management information fully with its downstream members.

The writer is a visiting senior research fellow at the Institute of Southeast Asian Studies.