The Mekong Delta under pressure

Seen from the air, the Mekong Delta looks endless: a green patchwork of rice fields, fruit gardens and rivers stretching to the sea. Around 17 million people live here, and the region produces roughly half of Vietnam's rice as well as much of its fruit and seafood. This rich landscape, however, is under serious threat, and the danger comes from several directions at once.

The most obvious threat is the rising sea. Much of the delta lies barely a metre above sea level, so even a small rise could flood large areas by the end of the century. In the dry season, salt water already pushes far up the rivers, damaging crops and leaving villages short of fresh water. During the severe droughts of 2016 and 2020, many families had to buy drinking water.

Yet the sea is only part of the story. In fact, the land itself is sinking, in many places faster than the sea is rising. The main cause is groundwater: farms, factories and households pump so much water from underground that the ground above slowly drops. Meanwhile, dams upstream trap much of the sediment that used to rebuild the delta, and sand mining removes even more from the riverbeds. Consequently, riverbanks and coastlines are being eaten away.

For decades, the main response was to build higher dykes and grow more rice, sometimes three crops a year. Although this raised production, it also stopped the annual floods from bringing fresh sediment to the fields, so farmers came to depend heavily on fertiliser. Since 2017, official policy has changed direction: instead of fighting a losing battle against nature, the delta should learn to live with it.

In practice, this means accepting salt water rather than trying to keep it out. In coastal provinces such as Ca Mau and Bac Lieu, many farmers now grow rice in the rainy season and raise shrimp in the dry season, when the water turns salty. Others have planted mangrove forests, which protect the coast from erosion and provide a home for fish and crabs. Some provinces are also trying to reduce groundwater use by supplying treated river water through pipes.

None of these solutions is perfect, and some, like intensive shrimp farming, carry their own environmental risks. Nonetheless, the change in thinking matters. The delta cannot be saved by concrete alone. Its future depends on whether people across the region, including the countries upstream, can work together to give the river back some of its natural power.