Seawater, soil harbingers of climate change

Update: August, 23/2015 - 14:45

Remnants: Seawater intrusion has destroyed forest in Thaïnh Phong and Thanh Phu districts in Ben Tre Province. — VNS Photo Bo Xuan Hiep

As the Mekong Delta feels the escalating effects of saline intrusion and coastal erosion, it must ready itself for the severe consequences of an age of global warming. Bo Xuan Hiep reports.

When Nguyen Thi Min woke up one morning two weeks ago, she was shocked to see that most of the 30,000 fish in her pond had died. Seawater had been intruding into the land for weeks, but it had suddenly worsened overnight, taking away her family's main source of income.

"The water had become so salty that we couldn't use it for cooking or washing," said Min, 54, who lives in Hung Phu Commune in Soc Trang Province's My Tu District.

Her husband, Nguyen Van Dung, wiping tears from his face, said: "Never in my life have I seen water that salty."

Growing threat: A family in Thoi Binh District in Ca Mau Province lost their house due to coastal erosion. By 2050, erosion will affect as many as 1 million people in the Mekong Delta. — VNS Photo The Anh

In the last several weeks, most of the 12 provinces in the Delta region have seen unprecedented levels of salinity, affecting crops and damaging livelihoods. The higher saline levels have also damaged protective forests along the coast, contributing to severe erosion.

Climate change is the chief cause, according to international experts.

Nguyen Van Lam, another farmer in Hung Phu Commune, said he had lost all of his fish in recent weeks.

"I wasn't aware of the salinity until I saw all of the dead fish," he said. Lam's family had spent VND160 million (US$7,360) to raise 25,000 catfish.

Dang Minh Phuong, a commune official, said that more than 70 fish-raising households had faced huge losses because of saline intrusion.

Seawater from canals has also affected fruit cultivation in Soc Trang, destroying about 700 ha of fruit in one area, according to Nguyen Hoang Co, deputy head of My Tu District's Agriculture and Rural Development Division.

Even Hau Giang, an inland province, has had to deal with high levels of saline water which entered through two canals.

Le Phuoc Dai, head of the province's Irrigation Sub-department, said the annual saline intrusion usually occurred from February to May, but this year it had extended through July.

Cam Quang Vinh, chairman of the People's Committee in the province's Phung Hiep District, said the level of saline intrusion had been the worst in 20 years.

In the coastal province of Kien Giang, at least 300,000 residents, including farmers engaged in animal husbandry, have been affected.

Water creeping in: The coastal commune of Hiep Thanh in Tra Vinh Province's Duyen Hai District has lost 500-800 metres of land to erosion since 2000. The Mekong Delta is losing 500 hectares to erosion every year. — VNS Photo Bo Xuan Hiep

Farmer Quynh Thi Kim Tuyen from the province's Hon Dat District said 700 of her ducks had died after drinking saline water. She lost VND40 million ($1,900).

Nguyen Van Tien, a farmer in An Bien District, who has lived in the area for more than 60 years, said: "I've never seen local people face such a severe shortage of water for domestic use."

He said that wells could not be drilled because the saline water had penetrated underground water.

Salinity has occurred as far as 50-60km inland in other provinces as well, including Ben Tre, Ca Mau, Soc Trang, Tien Giang, Tra Vinh and An Giang.

Rice farming

Seawater intrusion, along with prolonged drought, has also affected the Delta's rice fields, destroying 6,000ha of summer-autumn rice.

Soc Trang has been the worst-hit province, with more than 5,600ha of summer-autumn rice lost, according to the Southern Irrigation Research Institute. A few months ago, saline intrusion and drought destroyed about 5,300ha of the autumn-winter rice crop.

This year, the drought occurred a month earlier than usual in the coastal provinces of Tien Giang, Ben Tre, Tra Vinh, Soc Trang and Kien Giang.

The water level in the Mekong River's upstream section [in southern Viet Nam] is now 10-40 per cent lower than normal, according to the institute.

Harm on the farm: A shrimp pond in Dam Doi District in the southernmost province of Ca Mau has been affected by seawater. Fish and shrimp have died en masse in many provinces in the Mekong Delta because of saline intrusion. — VNS Photo The Anh

To fight the effects of drought and salinity, the region needs more funds to upgrade irrigation canals and forecast water availability, according to Quach Van Nam, director of Soc Trang Province's Department of Agriculture and Rural Development.

In Kien Giang, as many as 2,000ha of rice have been affected by saline intrusion.

Nguyen Van Tam, director of the province's Department of Agriculture and Rural Development, said the lack of freshwater from the upstream had also contributed to higher levels of salinity.

The flow of water from the upstream Mekong River had slowed, caused partly by the construction of new hydropower dams in other countries. The water from these upstream areas helped flush out seawater in downstream areas.

The drought in Kien Giang, which began in early July, had been the worst in the last 15 years, Tam said.

Elsewhere, in the southernmost province of Ca Mau, no rain has fallen for months. About 500 out of 2,000 households in Thoi Binh District are short of water for daily use.

Coastal erosion

The Mekong Delta is also losing 500ha of land to erosion every year as land accretion fails to make up for areas being washed away. Erosion is damaging almost the entire coastline of the Delta.

Hydropower dams in countries along the Mekong River's upstream and increased sand mining in rivers have contributed to erosion and loss of sediment.

The Delta has 265 erosion hotspots, according to Dao Trong Tu, adviser to the Viet Nam Rivers Network, the country's largest advocacy group for water-resource protection.

Sliding into the sea: Coastal erosion in Thoi Binh District in Ca Mau has become a serious issue. — VNS Photo The Anh

By 2050, the number of people affected by erosion in the Delta is expected to soar to 1 million.

An Giang, one of the most flooded provinces in the region, has been hardest hit by erosion.

The province has around 50 erosion hotspots with a total length of 150km along the Tien (Front) and the Hau (Rear), two tributaries of the Mekong River.

As many as 6,000 households in the province live in vulnerable areas and await relocation to safer, erosion-proof areas, according to Do Vu Hung, deputy director of An Giang's Department of Agriculture and Rural Development.

Le Thanh Trieu, chairman of the U Minh District's People's Committee in Ca Mau, said that the Khanh Hoi estuary had been losing 50 metres of land each year, threatening the safety of 500 households. The province has been urged to build embankments at a cost of VND100 billion ($4.76 million).

Cao Van Nam, head of the Kien Giang Province's Irrigation Sub-department, said the destruction of coastal protective forests was one of the major causes of erosion of sea dykes.

"Erosion will worsen if no measures are taken to recover and develop coastal mangrove forests outside dykes," Nam said.

Learning to adapt

In recent years, the Vietnamese Government has carried out many climate-change adaptation programmes, but the results have been insufficient.

The Ministry of Agriculture and Rural Development, for example, has urged provincial committees to give priority to preventing erosion in vulnerable coastal areas. It has also called on research institutes to assess the level of coastal erosion, create silt deposits in coastal areas, and plant trees to check encroaching sea.

In Tra Vinh, the Ministry of Agriculture and Rural Development in 2008 approved construction of concrete dykes at a cost of more than VND530 billion ($24.29 million).

But to build a comprehensive dyke system to protect the residents, Tra Vinh needs at least an additional VND1.5 trillion ($68.76 million), according to the provincial People's Committee.

Kien Giang has been replanting protective forests in erosion-prone areas, but has had limited results, partly due to the adverse impact of aquatic farming and fishing.

Meanwhile, Tien Giang has spent nearly VND25 billion ($1.14 million) to dredge irrigation systems and Bac Lieu spent more than VND83 billion ($3.8 million) to build 300 irrigation works.

To fight drought and saline intrusion, the Government recently approved a grant of VND282 billion ($12.92 million) for the Mekong Delta and south-central regions.

International organisations have also been involved in climate-change adaptation programmes.

One major programme with positive results, funded by the Asian Development Bank (ADB), is the Phuoc Hoa Water Resources Project implemented in HCM City and surrounding provinces, as well as the southwestern provinces of Binh Phuoc, Tay Ninh and Long An.

The project, begun in 2003, is financed with $150 million in loans.

Under the project, the Phuoc Hoa dam and an irrigation canal have provided more water for salinity control and irrigation for agricultural use in HCM City and neighbouring provinces.

The dam and canal convey about 1 billion cubic metres of water every year from the Be River to the Dau Tieng Reservoir on the Sai Gon River.

More water is also being sent to the Sai Gon and Vam Co Dong river basins for farming, domestic and industrial use in the region.

In addition, two new irrigation areas will be built in Tay Ninh and Long An provinces, where farmers and other water-user groups will operate and manage on-farm irrigation facilities.

Besides ADB, the Prime Minister has approved a technical assistance project funded with $4.18 million from the World Bank and $380,000 from the government. It will operate from August 2015 to July 2019 with support from the Ministry of Science and Technology.

The funds will be used to set up the Viet Nam Climate Innovation Centre, which will help small- and medium-sized enterprises with climate-technology solutions and green business activities.

In addition, the German International Cooperation Agency (GIZ), with assistance from the Ministry of Natural Resources and Environment, will offer technical support to help the government incorporate ecosystem-based adaptation into its climate-change policies.

Viet Nam is one of the countries in the world most vulnerable to climate change, particularly rising sea levels. Experts have warned that the country must immediately develop an action plan to ensure a climate-resilient future before it is too late.

While local and foreign experts develop new adaptation models, farmers like Min and her husband in Soc Trang can only hope that the new programmes will provide sustainable solutions.

Although Min said she had "heard about climate change for a number of years", she and her husband had never been aware of its serious consequences until this year, when their incomes were cut short and their lives directly affected. — VNS