BANGKOK—Rice crops around Vietnam’s Mekong River Delta are suffering from a dangerous lack of freshwater, and an agriculture expert who blames climate change says the problem will likely worsen.
As drought spreads across Asia, the Mekong River has fallen to its lowest levels in decades and seawater is encroaching into the lower river’s Delta area, flooding fields with salt.
Pham Van Du, deputy director of the Department of Agricultural Cultivation in southern Vietnam’s Can Tho city, said that in recent years the encroaching saltwater has expanded in volume and the problem is likely to get worse as climate change becomes more severe.
“In my opinion, weather changes have made a clear impact. That is to say, the meteorological condition of the Lower Mekong has changed slightly,” he said.
“Drought has been severe, and water during the dry season has become even scarcer compared with previous years. As a result, saltwater has flowed into all parts of the Lower Mekong and the water has become from 3,000 to 4,000 parts saltier.”
This year, more than 100,000 hectares (nearly 250,000 acres) of rice, equivalent to 16 percent of the land used for Mekong Delta winter-spring rice harvests, is at risk of damage from saltwater encroachment.
Provincial officials have been tasked to estimate the extent of the damage.
A lack of fresh water, droughts, and saltwater encroachment generally occur simultaneously in Vietnam, but this year the situation has been complicated by upstream countries reporting Mekong River depths at their lowest in nearly 20 years.
During the dry season, seawater can normally flood up to 18 miles (25 kms) inland, but under current conditions the area of flooding has encroached nearly 40 miles (64 kms) into the delta.
According to a report by the Laos-based Mekong River Commission (MRC), low water levels in the Upper Mekong are affecting freshwater levels, navigation, and hydropower supply for tens of millions of riparian communities.
The river in Laos and Thailand is at its lowest since 1992, while in southwestern China the water level has dropped below its lowest mark in 50 years to just half of its average for this time of year, the organization said in a recently released study.
Heavy boats are currently unable to sail through many stretches of the river where low water levels have left sand bars and large rocks exposed.
River tour operators have halted services on several stretches of the Mekong in Laos, hampering the tourism industry, while around 60 cargo ships are backlogged for deliveries because they have been unable to navigate the shallow river.
At the end of February, a Lao Water and Environmental Resources official in Luang Prabang publicly accused Chinese dam operators of contributing to the low level of the Mekong by retaining water for irrigation and electricity generation.
China is home to eight dams that are either built or undergoing construction on the Mekong.
“If China doesn’t release water, we have a problem. We don’t have water for our tributary rivers either. The Nam Ou, Nam Khan, and Nam Xieng rivers are all dried up,” the official said. “When China shuts its dam water gates, we in Laos cannot use our boats.”
Tek Vannara of Cambodia’s Association for Environmental Protection said construction for irrigation and the building of hydropower dams upstream is exacerbating conditions in the lower Mekong and affecting fishing in Cambodia.
He said the low river levels prevent natural water distribution to dikes and lakes, hampering fish migration to breeding grounds.
“Development projects [are responsible], such as opening new waterways for ships, the utilization of water for agricultural work, and other major projects such as hydropower dams,” he said.
“Other issues that we should look at are the sources providing water to the Mekong. These areas are mostly agricultural regions, especially in Thailand where they have diverted lots of water from the Mekong to use in farming.”
‘Dams not to blame’
But while downstream inhabitants are quick to blame northern neighbors for restricting water flow through the use of hydropower dams, the MRC said the recent drop in volume is unrelated.
Thailand, Laos, and Vietnam are all building dams in addition to those already built by China.
Instead, the MRC says, the water shortage is largely a result of an early end to the 2009 rainy season and lower-than-average rainfall during the monsoon season.
"At this stage there is no indication that the existence of dams upstream has made the situation more extreme than the natural case," The Associated Press quoted from the report.
Sin Niny, vice chairman of the Cambodia National Mekong Committee and a member of the MRC Joint Committee for Cambodia, said the use of upstream hydropower dams actually regulates the flow of the Mekong between rainy and dry seasons.
“Saying that this low level was caused by the construction of hydropower dams in the Upper Mekong is wrong,” he said.
“If [those countries] hold water in the rainy season, they will release it in the dry season so that their hydroelectric projects work. As a result, the water will flow down anyway.”
On Wednesday the MRC hosted a meeting in Luang Prabang, Laos, of senior officials from member countries. Cambodia, Laos, Thailand, and Vietnam are all members of the commission, while China and Burma are not.
The Mekong supplies water to an estimated 65 million people as it winds its way through these six countries.
MRC officials have indicated that they will hold talks with Chinese officials, but have not set a date to do so.
Le Van Banh, director of the Mekong Delta Rice Institute, said it is imperative that all countries along the Mekong work together to devise methods of sustainable use for the water source.
“It is hoped that Vietnam can unite its efforts with those of other countries in using the Mekong River’s water power through cooperation and international agreements,” he said.
“On the contrary, if each country in the Mekong River Committee takes its own actions for its own benefits, then all will suffer and the Mekong Delta will endure more damage.”
Original reporting by Nam Nguyen for RFA’s Vietnamese service with additional reporting by RFA’s Khmer service and RFA's Lao service. Vietnamese service director: Khan Nguyen. Khmer service director: Sos Kem. Lao service director: Viengsay Luangkhot. Translated from Khmer by Vuthy Huot. Written for the Web in English by Joshua Lipes. Edited by Sarah Jackson-Han.