Professor Dao Cong Tien, former head of the HCM City Economics University, says that if the sea level rises by one metre and no countermeasures are taken, one-third of Vietnam’s Mekong Delta will be underwater and nearly 20 million people will have to co-exist with salt water.

On the other hand, Tien adds, that if the delta builds works to prevent the encroachment of salt water, there will be huge infrastructure construction costs and the delta will be seriously polluted by industrial wastewater.

Some hydrologists have calculated that to cope with a one meter sea level rise, a coastal dike of over 700 kilometers in length and at least 3 meters high and thousands of big sewers will be needed to protect the Mekong River.

The Mekong Delta has dozens of industrial zones and more than 200 industrial complexes. These facilities discharge more than 50 million cubic metres of industrial wastewater and over 220,000 tonnes of industrial rubbish annually.  Seventy percent is untreated.

The Delta environment also has to cope annually with over 500 million tonnes of waste from shrimp and fish ponds, toxic residues from two million tonnes of pesticides and over 500,000 tonnes of fertiliser, over 600,000 tonnes of waste from daily life and over 100 million tonnes of wastewater from daily life.

Scientists say that the pollution of the Mekong Delta is serious but the delta doesn’t have a comprehensive plan to solve this problem. Meanwhile, according to the industrial development plan for the Mekong Delta, the total area taken by industrial zones will reach 31,500 hectares in 2010 and 50,000 in 2020.

Dr. Nguyen Thanh Chuong from the Central Propaganda and Education Committee concurs that finding a solution is a huge problem.  If the Mekong Delta is surrounded by dikes and barriers to prevent the encroachment of salt water, he says, the self-cleaning mechanism of local rivers will be useless and the delta will surely become entirely polluted as wastewater will not be able to flow into the sea.

Nearly 30,000 kilometers of rivers and canals in the Mekong Delta could become dead waterways.

Chuong’s scenario is highly plausible.  Already some areas in the Mekong Delta have experienced heavy pollution because of closed dike systems and sewers designed to prevent salt water intrusion, for example the Go Cong peninsula in Tien Giang province and the area around Ca Mau City in Ca Mau province.

Dr. Vo Hung Dung, director of the Chamber of Commerce and Industry’s Can Tho city branch, said that in the “race” to industrialisation, many provinces in the Mekong Delta have accepted investment projects that cause environmental pollution but have not insisted they include waste and wastewater treatment facilities.

Dung said that the Mekong Delta environment is very sensitive and vulnerable. If it allows industrial development without wastewater treatment solutions, the region’s environment will be changed and if it changed, it would be very difficult to recover.

“If one-third of the delta’s area is flooded by sea water, losses would be huge. But if the entire delta is polluted by wastewater, the losses could be many times higher,” Dung said.