Monday 25 Jun 2018
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The Mekong Delta, Vietnam

The Mekong Delta (Vietnamese: đồng bằng sông Cửu Long “Nine Dragon river delta”) is the region in southwestern Vietnam where the Mekong River approaches and empties into the sea through a network of distributaries. The Delta spans over an area of 39,000 km² and offers natural resources for over 17 million inhabitants living in 13 of the 58 provinces of Vietnam.

The climate in the Mekong Delta is influenced by both the southwest and northeast monsoons. In general the dry season runs from December to April while the wet season spans May to November. The marked seasonality in rainfall leads to both annual floods and water shortages in the Delta. In the wet season almost 50% of the Delta is flooded (1,900 km2). In the dry season, flow in the Mekong is insufficient to prevent saline intrusion and extensive salinization of waterways occurs in the lower Delta. The whole of the Ca Mau Peninsula in the Delta’s southwest is salinized for 6 months during the dry season as there is insufficient freshwater flow in the Mekong to displace saline intrusion from the southwestern sector of the Delta.

While the Delta is characterised by highly productive soils and abundant water ressources in the wet season, which are very efficiently used for agriculture and aquaculture, there are also a range of internal and external threats posing serious pressure and risks on the delta and its people. Frequent flood and drought events, increasing salt water intrusion and salinization of soils, limited drinking water availability, unsustainable land use intensification and sand mining, coastal and river bank erosion, subsidence, and the growing threat of climate induced sea level rise and typhoons all have negative effects on people’s lives in the Delta. Furthermore, regulatory measures at the upper reaches of the Mekong, i.e. the construction of hydropower dams, lead to severe changes in discharge, sediment, and bedload patterns downstream, exacerbating salt water intrusion, accelerating rates of deltaic loss and river bank erosion and threatening the high productivity and long term stability of the Mekong Delta.

All these developments renders the Delta unable to fulfil its important ecological services and leads to increasing challenges for planners and authorities to ensure a sustainable management of the region. In this context, an important aspect to support planning processes is the availability of a consistent and up-to-date data- and knowledge base on the most relevant key themes as well as operational instruments for the effective communication and distribution of information.

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