Viet Nam

Viet Nam's rich Mekong and Red River Deltas face severe flooding from climate change

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Bangkok/Ha Noi, 15 December 2009 - Climate change will have serious consequences for Viet Nam's Mekong and Red River Deltas - two key rice and agricultural producing areas in the country - unless global warming is addressed.

The Red River Delta, particularly Quang Ninh province, and the Mekong River Delta are densely populated areas and home to over 40 percent of the country's population.

Both have emerged as the most vulnerable areas in the Viet Nam Climate Change Assessment Report. The Report has been compiled by the Institute of Strategy and Policy on Natural Resources and Environment, the Ministry of Natural Resources and Environment with the support of the United Nations Environment Programme (UNEP).

"These two Deltas play an important role in the economic health of the country and in the livelihoods of the people who live there. More than one-third of the Mekong Delta, where 17 million people live and nearly half the country's rice is grown, could be submerged if sea levels rise by one metre. Even under a low emission growth scenario, a fifth of the delta could be flooded," said Dr. Young Woo Park, UNEP's Regional Director for the Asia-Pacific Region.

Viet Nam is considered one of countries in the world which will be most severely impacted by climate change. Over the last 50 years, the country has been experiencing increases in temperatures ranging from 0.05 - 0.20 Celsius per decade, rainfall patterns have also changed, with increasing rainfall in the northern region and decreasing rainfall in the southern region, and sea levels have risen between 2-4 centimeters per decade.

Projections by the Intergovernmental Panel on Climate Change (IPCC) indicate that Viet Nam will be one of the 12 countries most affected by sea-level rise. With a rise in sea-level of 1-metre, it is anticipated that more than 12 percent of the land will be lost, affecting up to 17 million people. A 2-metre rise in sea level would see land lost increase to 16 percent and could cost up to a third of the country's GDP.

In addition, a sea-level rise could have other important economic impacts along the coastline:

- Expenditures on the maintenance, repair and operation of existing infrastructure are likely to increase;

- Run-off regimes of major rivers where hydropower stations are built would change, affecting water regulation mechanisms and hence the power generation capacity;

- Inundation of lowland areas would increase energy requirements for drainage pumping.

The country has developed a number of mitigation and adaptation policies to address the issue that includes more efficient and economical use of energy, including renewable, the protection of its forest resources, and the introduction of new farming techniques and technologies.

These measures include conserving and restoring existing forests, planting five million hectares of forest on marginal and degraded land, prevention of forest fires and burning of crop residues, the selection of short-duration, high-yield rice varieties, improvement of irrigation-drainage management in rice fields, and research and development of small and micro hydro-power plants.

For more information please contact:

Nick Nuttall, UNEP Spokesperson/Head of Media: Tel. +254-20 7623084/+254 733 632 755 or while traveling: +41 79 596 57 37, Email:

Ms. Satwant Kaur, Tel: 02 288 2127/02 288 2314; Mobile: 083 9086000; Email:;


Copies of the report can be downloaded at:

Climate Change Impacts in Viet Nam

Water Resources

Viet Nam is located in the downstreams of two major international rivers: Mekong River with annual run-off of 505 billion m3 to and the Red River with annual runoff of 138 billion m3 of water to the East Sea. As a consequence of climate change, annual run-off is projected to increase within the range from 5.8 to 19.0% for the Red River and from 4.2 to 14.5% for the Mekong River.

Food Production and Agriculture

An estimated 85 percent of the people in the Mekong Delta are supported by agriculture. The sea level becoming remarkably higher along the coastline in Viet Nam will bring about salinity intrusion and salt water inundation in the Mekong River Delta. More than one-third of the delta, where nearly half the country's rice is grown, could be submerged if sea levels rise by three feet in the decades to come. Even under a low emission growth scenario, one-fifth of the delta would be flooded. Significant cultivation areas in Mekong and Red River Deltas would also be affected by salt water intrusion due to sea level rise.


The sea-level rise would result in a decline in the mangrove forest area, and adversely affect indigo forests and forest planted on the sulfated land of provinces in the south of Viet Nam. There would be changes in boundary distribution of primary forests as well as secondary forests. Significant cultivation areas in the Mekong and Red River Deltas would also be affected by salt water intrusion due to a sea-level rise.


Increasing coastal water temperatures would accelerate mineralization and organic decomposition processes and affect the food system of living creatures, while salinity would destroy the habitat of fresh water species. Distribution of economical fishery resources in the coastal waters of Viet Nam would become more dispersed as the number of sub-tropical fish (with high commercial value) would decrease or even disappear. Most fishes that breed in coral reefs would vanish. Meanwhile, the number of tropical fish with low commercial value, except tuna, would increase.


Warmer climate would have adverse impact on human health. Extreme weather would lead to increased heat stress thus threatening particularly old people and those suffering from cardiac diseases. There are many infectious diseases which would be exacerbated by climate change such as: malaria, synaptic filariasis, dengue fever, Japanese encephalitis, arboviral diseases that are considered to be common in humid tropical regions, through facilitating the growth and development of various viruses and insects which are disease carriers, leading to an increase in patients and death rates.

Energy and Transportation

More severe typhoons and sea-level rises would lead to extensive damage to existing energy sector infrastructure, offshore drill platforms, systems for transporting oil and gas to the shore, and electricity transmission and distribution systems. Run-off regimes of major rivers where hydropower stations are built would change affecting water regulation mechanisms and hence the power generation capacity. Sea-level rises would also inundate lowlands, leading to an increase in energy requirements for pumping out water for drainage. Increasing temperatures would affect expenditures of coal mine ventilation and cooling, which would result in increased expenditures for cooling and a decrease in the efficiency and energy productivity of thermal power plants.