Central Vietnam floods cut roads and schools, but reservoirs stay dry

Six low-water crossings in Dakrong Commune sat under 2 to 2.5 meters of water on Tuesday, as heavy rain battered central Vietnam and cut road links across Quang Tri, Hue and Da Nang — while the region's hydropower reservoirs, the ones that actually need the rain, stayed nearly seven meters below where they should be.

The storm's logistics footprint is road-based: flooded highways, landslide-blocked routes and isolated communes. For carriers and forwarders moving goods through central Vietnam this week, the disruptions concentrate on the Ho Chi Minh Highway and National Highway 49, two of the corridor's key arterials.

What happened on the ground?

In Da Nang, authorities evacuated three households — 13 residents — from Tra Leng Commune on Tuesday morning after inspectors spotted signs of a possible landslide on the hillside behind their homes. Falling soil and rocks had already damaged several roads in the commune, prompting warnings for residents to steer clear of high-risk slopes.

Forecasters expect Da Nang to receive 100-250 mm of rain, with localized totals exceeding 350 mm over two days. River flooding is expected from Tuesday through Thursday, raising the risk of inundation in low-lying areas, flash floods and landslides in mountainous zones.

In Hue's A Luoi 2 Commune, water depths of 20-30 centimeters flooded sections of the Ho Chi Minh Highway. Landslides around Ta Luong Pass and along National Highway 49 temporarily disrupted traffic, according to Le Trung Hieu, chairman of A Luoi 5 Commune's administration.

The Hue Hydrometeorological Station recorded exceptional rainfall between 10:00 pm Monday and 4:00 am Tuesday:

• 250.4 mm in Nam Dong
• 207.8 mm in Huong Son
• 177.8 mm in Hong Thai

In Quang Tri, the picture was similar. Landslides blocked part of Route 9C in Kim Ngan Commune. Rising rivers and fast currents isolated some remote communities, and authorities deployed police and local response teams to barricade dangerous crossings. In Hieu Giang Commune, the Hieu River was rising rapidly, flooding local roads and low-lying ground.

Why did schools close?

School shutdowns spread across three provinces, and in one case the trigger was not the rain itself but a dam release. The Huong Dien hydropower plant began discharging 1,000-1,500 cubic meters per second into the Bo River, one of Hue's major waterways. Huong Tra Ward responded by ordering all students to stay home.

"The department has instructed school principals to closely monitor weather conditions and decide whether to suspend classes when necessary," said Nguyen Tan, head of the Hue Department of Education and Training. Huong Tra, Hoa Chau Ward and several schools in the A Luoi area suspended classes on Tuesday morning.

In Hoi An Dong Ward in Da Nang, all kindergarten, elementary and middle school students were told to stay home from Tuesday until further notice.

Why are the dams still short of water?

Here is the paradox at the center of this event. Despite the downpours hammering the lowlands, the major reservoirs in the upper Vu Gia-Thu Bon river basin remain far below normal levels.

At the A Vuong hydropower plant, the reservoir sat nearly seven meters below the spillway threshold on Tuesday morning. Operators say it needs more than 181 million cubic meters of additional water to reach normal storage, and the plant is generating electricity only at minimum levels.

Song Tranh hydropower has shut down both turbines entirely to conserve what water it has.

The rain, in short, is falling in the wrong places. Lowland basins are flooding while upland catchments stay thirsty.

What does this change for the dry season?

The Da Nang administration has flagged the commercial risk plainly: drought, water shortages and saltwater intrusion in the Vu Gia-Thu Bon basin remain major concerns for the 2027 dry season if the reservoirs fail to accumulate sufficient water during the rest of the rainy season. Power generation at minimum output, turbines idle, roads periodically cut — the region's water and transport infrastructure both hinge on whether the remaining weeks of the rainy season deliver rain to the upper basins, not just the floodplains.