A 40-meter section of National Highway 91 fell into the Hau River, a branch of the Mekong, on Wednesday morning. 

The highway and the soil beneath in Binh My Commune in An Giang Province’s Chau Phu District slipped into the river after a crack opened up four days earlier.

There were no casualties but the crack is continuing to open up further, forcing authorities to evacuate dozens of households nearby.

Nguyen Van My, 70, who lives just across from the collapsed section, said the crack had kept widening in recent days until it reached 20-30 centimeters on Wednesday morning and the entire section broke away and fell into the river.

The collapsed section was around 10 meters wide, or more than one third of the highway’s width.

"No one can tell when the erosion will stop," My said. "We really hope the authorities can relocate us to somewhere safer."

This is not the first time a portion of the highway has fallen into the river in Binh My.

In August last year a 85-meter-long section fell into the river, followed a few weeks later by a 30-m section.

The stretch had been reinforced with sand bags at a cost of VND25 billion ($1.07 million), but 90 percent of them also fell into the river.

The latest eroded section is just 100 meters from the previous ones.

National Highway 91 after a section slipped into the Hau River, May 27, 2020.
Photo by VnExpress/Cuu Long.

An Giang Province has already built a five-kilometer bypass for vehicles to avoid the highway in Binh My.

The 142-km National Highway 91 runs from the Cambodian border in An Giang to Can Tho City.

In the delta, Vietnam's agriculture and aquaculture hub, a total of 786 kilometers of roads face a threat of erosion at 562 riverine and coastal locations.

It is losing 500 hectares of land to erosion annually, and this is expected to directly impact the lives of one million people by 2050, according to the Ministry of Agriculture and Rural Development.

Experts have been citing several causes for the delta erosion.

The construction of dams in the Mekong River’s upstream area has affected its natural flow by holding back sediments, and the water is flowing much faster, they said.

Other reasons include overexploitation of groundwater in the delta and sand mining in branches of the river.

In September last year Prime Minister Nguyen Xuan Phuc said the government would allocate VND3 trillion ($128.6 million) to combat land erosion in the delta in 2019-20.

In the last 10 years VND16.1 trillion ($694 million) has been spent on anti-erosion works in the delta. In 2018 and 2019, VND4.04 trillion ($174 million) was allocated for the purpose, Minister of Agriculture and Rural Development Nguyen Xuan Cuong said at a meeting with leaders of delta provinces.