Local resourcefulness to resolve the Mekong Delta’s water issues

Source: Southern Institute of Water Resources Research

More than 3,000 households in Phu Tan commune in Tan Phu Dong district of the Mekong Delta province of Tien Giang have been suffering from daily shortages of fresh water, forcing them to use saline water for washing and cleaning to save fresh water.

Tran Thi Xem, a local resident, said that they have to ration fresh water to have enough for cooking and drinking. “Each family must dig holes covered with awnings to store fresh water. The water has a different colour and is sometimes full of dead insects, but we have to use it,” she said.

Not only Tien Giang, neighbouring Hau Giang is also under siege by saline intrusion, and local authorities have been encouraging people to store fresh water. Besides, the province has also completed 32.5 kilometres of dykes, 20 open culverts, and 18 circular culverts to create a system of dykes, sluices, and dams to prevent saltwater intrusion as part of the action plan by 2020 with vision to 2030.

Besides, farmers across the Mekong Delta are also switching to fast growing trees like peanut, pineapple, and dragon fruit, instead of depending on rice.

Meanwhile, to keep themselves out of fresh water shortages, many enterprises have opted to develop their factories in industrial zones (IZs) where there are often stable fresh water supplies. For example, US-based Cargill Vietnam has seven factories at IZs across the Mekong Delta where it has been able to secure sufficient fresh water for production.

According to Cargill’s Public Relations Department, so far they have not noted any decrease in production due to saline intrusion, while the impact of African swine fever was deeply felt.

Severe alinity intrusion

According to the latest report of the Southern Institute of Water Resources Research, saline intrusion in many river estuaries in the Mekong Delta is higher than last year, and can encroach 40 to 50km farther inland.

For example, on the Vam Co River, salinity intrusion has been 70-80km, which is 18-30km farther in than during the 2017-2018 dry season, but 10-20km back against 2015-2016.

In terms of salinity, the highest rate measured at Ben Luc Station on the East Vam Co River is 5.8 per mille, while it was 4.9 per mille at Tan An Station on the West Vam Co River – 4.5 and 4.4 per mille higher than in the last dry season, respectively. Recently, salinity levels of 4 per mille have been measured in the estuaries of Cua Dai, Co Chien, and Ham Luan rivers in Ben Tre province.

Adaptation by technology

In order to adapt to climate change and ensure their livelihood, locals have been proving tremendously resourceful in utilising technology.

People in Luong Hoa A commune of Chau Thanh district in Tra Vinh province now can farm much easier. They can check water salinity without having to taste it or use traditional measurement methods, while at the same time, they can turn pumps on and off around the farm – all on the same smart mobile phone app.

“With the Rynan water monitoring app, I can easily tell the water level, salinity, PH, and turbidity to decide whether to pump water or not. I can even pump water when I go out with friends,” Truong Van Thanh, a local farmer, said.

Besides the Rynan app, to improve the quality and efficiency of his rice farm, Thanh has recently begun using smart fertiliser. “A dose of this fertiliser is planted along with each young rice stalk by a machine. It saves expenses, human work, and improves productivity by 20-30 per cent,” Thanh explained.

The technologies Thanh uses are made by Rynan Agrifoods, a company established by 60-year-old overseas Vietnamese Nguyen Thanh My in 2016.

Witnessing the loss of thousands of hectares to salinisation, My decided to build a buoyant salinity level measuring station. “These buoys are attached to sensors. Every 15 minutes, the sensors upload information on the Internet where people can access it by mobile phones,” My told VIR.

Currently, Tra Vinh province has invested VND1.5 billion ($434,800) in the installation of 10 buoys in five districts, and Rynan Agrifoods donated an additional three. Each buoy can collect information on an area of 10 square metres.

“We use simple and cheap pump gateway controls to make irrigation systems that were installed dozens of years ago smart,” My explained, adding that the tool costs only VND1 million ($43.47) – he can even give it away for free. “The pump gateway controls help save over 30 per cent of water and reduce greenhouse gas (GHG) emissions by 50 per cent.”

The company’s smart fertiliser also helps reduce GHG emissions, which is especially important as rice planting in Vietnam has been the second largest source of GHG emissions after power production.

While My has been helping famers adapt to climate change, three architects from the Hanoi Young Intelligentsia club have been helping desalinate water for everyday consumption.

After the 2016 dry season, Tran Vu Thanh, chairman of the club, started by installing 13 salt water purifiers with the capacity of 300 litres per hour in seven provinces. So far, more than 20 purifiers have been installed at schools in nine provinces of the Mekong Delta and on the Spratly Islands.

“Most of the purifiers have been installed with funds collected by a charity programme run by Hanoi Young Intelligentsia,” Thanh said, explaining that the system produces water meeting the drinking water standards of the Ministry of Health.