Salinity Intrusion in the Vietnamese Mekong Delta, a Threat: Possible Causes, Effects on People’s Life and Production, and Temporary Solutions and Adaptable Strategies

Abstract

The Vietnamese Mekong Delta is the most important agricultural production area in Vietnam. Most of this deltaic plain has an extremely low mean elevation of about 0.8 m above sea level and dissected by an inter-linked system of natural rivers and man-made canals connected to the sea. It is recognized as one of the areas worldwide most vulnerable to the impacts of climate change. In recent years, saline intrusion into the Vietnamese Mekong Delta has become increasingly serious due to a combination of factors, including the low topography, a dense system of rivers and canals connected to the sea, drought, low flow rates in the Mekong River during the dry season, growing competition for rapidly depleting water resources, sea level rise, and land subsidence. In 2020 saltwater intruded further inland than ever before and affected 10 out of 13 provinces of the Vietnamese Mekong Delta, causing severe damage to millions of hectares of farming land and the livelihoods of thousands of households. Solutions and adaptation strategies include storage of fresh water in ponds, shifting to farming systems and varieties that are more resilient to high salinity, changing cropping schedules, and building sluices to regulate saltwater intrusion. This paper discusses the main causes of salt intrusion, its effects on people’s life and production, and adaptation strategies to mitigate its impacts.