Climate change will lead to the flooding of nine urban centers in Vietnam’s Mekong Delta in mid-21st century, with Can Tho being the hardest hit.

A new study by the Institute of Hydrometeorology and Environment Sciences at the Ministry of Natural Resources and Environment “Impacts of climate change on the water resource and adaptation measures” suggests that floods may submerge more than three million hectares or nearly 90 percent of the delta under more than one meter of water.

While towns such as Chau Doc and Long Xuyen in An Giang Province, and Cao Lanh in Dong Thap are already vulnerable to flooding, the study says many more areas will be easily flooded by 2050.

The list of towns under threat includes Sa Dec in Dong Thap Province, Vinh Long in Vinh Long, Tan An in Long An, My Tho in Tien Giang, Vi Thanh in Hau Giang, Soc Trang in Soc Trang Province, Rach Gia and Ha Tien in Kien Giang, and Can Tho.

The rising sea level will make it more difficult for drainage in other towns of the delta, says the study which investigated seven river basins across the country – Hong and Thai Binh in the north, Thu Bon and Ba in the central region, and Dong Nai and Mekong comprising Tien and Hau Rivers in the south.

In the Hong and Thai Binh rivers, the water flow during high flooding will increase by 11-25 percent in 2100. Together with the rising sea level, this will threaten nearly 3,000 kilometers of dykes protecting the northern delta.

Around the Thu Bon and Ba Rivers, the estimated flood area will also enlarge by 4 percent by 2050 and nine percent by 2100.

The study also warns about severe salinization in the deltas starting 2050.

By 2050, 2.5 million of the delta will be salinized. Sea water will invade up to 10 kilometers upstream of the largest southern river Dong Nai, affecting the socio-economic development of the region, especially Ho Chi Minh City, says the report.

Sea water will invade three to nine kilometers further into the Hong and Thai Binh river basins by 2100, around three kilometers into the Ba River, and eight kilometers of several tributaries of the Thu Bon River.

Power plants also victims

The study says climate change will affect the flow of rivers and the output of hydropower plants.

Plants in the central and southern regions are forecast to see their output drop at least three percent by 2050 and six percent by 2100.

Doctor Hoang Minh Tuyen, deputy director of the project, said authorities at the river basins should cooperate with neighboring countries to manage water resources better.

Tuyen suggested that authorities develop reservoirs, recover forests and build dykes to prevent salinization.