Hydropower dams lower water levels as Vietnam braces for storm Koto

Storm Koto entered the East Vietnam Sea on Tuesday night, making it the 15th storm to hit the region in 2025.

In Dak Lak Province, Luong Nguyen Minh Triet, secretary of the provincial Party Committee, said storm-response plans were activated while the province remains overwhelmed by damage from the historic floods.

Deputy Prime Minister Tran Hong Ha is scheduled to meet local authorities on Wednesday to direct response measures, Triet added.

Dak Lak’s Civil Defense Steering Committee has ordered controlled operations at major reservoirs, requiring the Song Ba Ha, Song Hinh, and Krong HNang hydropower plants to lower water levels to flood-receiving thresholds by 10:00 am on Friday.

The targets are 102m at Song Ba Ha, 204.5m at Song Hinh, and 251.5m at Krong HNang.

Operators must strictly follow regulations to avoid sudden, dangerous releases downstream.

In Khanh Hoa Province, director of the provincial Department of Agriculture and Environment Nguyen Duy Quang said evacuation plans will be implemented if Koto directly affects the province. Local authorities will also assist residents in reinforcing homes.

Reservoir operators must monitor weather patterns, rainfall and river flows closely, adjusting discharges to protect dam safety and prevent downstream flooding.

Le Huyen, vice-chairman of the Khanh Hoa People’s Committee, said all households whose homes collapsed or were badly damaged in the recent historic floods will be evacuated immediately if Koto threatens the area.

Two major reservoirs, Song Cho 1 and Suoi Dau, began lowering water levels on Monday to prepare for incoming rain.

Flood-hit communities on alert

In the hard-hit communes of Hoa Thinh and Hoa My in Dak Lak Province, residents spent Tuesday repairing damage while preparing for the incoming storm. Many remain traumatized by the previous disaster and have become more vigilant.

Pham Thi Lat, 62, of Hoa Thinh Commune, said she now regularly reinforces her home whenever she hears storm warnings.

“When authorities announce the storm’s landfall, I’ll shelter in a neighbor’s house with a second floor. When the storm passes, I’ll return home,” she said.

At Dong Khoi Middle School, principal Tran Van Sau said computers unaffected by recent floods will be moved from the second floor to the ground floor to prevent roof-loss damage.

“We will finish storm preparation at least one day before its landfall,” the school’s leader said.

Local officials in Hoa Thinh and Hoa My said vulnerable families, especially those living in cracked or partially collapsed homes, will be relocated early.

Trees at risk of falling will be cut, and if many households require shelter, public buildings and schools with upper floors will be used as storm-safe sites.

Low-lying neighborhoods prone to re-flooding will also be evacuated early if heavy rains occur.

Ho Chi Minh City orders reservoirs to lower levels

The Ho Chi Minh City People’s Committee has instructed all reservoir operators servicing the city to proactively lower water levels.

Bui Minh Thanh, vice-chairman of the city’s administration, emphasized dam safety and flood prevention when storm Koto combines with high tides and necessary flood releases.

State-run firms like Southern Irrigation Management Company, Tri An Hydropower Company, and the city’s Irrigation Works Management Center must review dam-safety systems, ensure spillway readiness, prepare emergency equipment, and immediately fix any structural defects.

Authorities must promptly notify downstream residents before water releases and regularly update discharge volumes and flood risks.

Storm Koto

The National Center for Hydro-Meteorological Forecasting reported that Koto's center at 1:00 pm on Wednesday was located about 280 kilometers east-northeast of Song Tu Tay Island, with sustained winds of 75-88 kph and gusts of 103-117 kph. The storm was moving west-northwest at about 20 kph.

The system is anticipated to intensify as it travels west-northwest at approximately 10 kph over the next 24 hours.

By 1:00 pm on Thursday, Koto is expected to be in the central East Vietnam Sea, about 150km north of Song Tu Tay, packing winds of 103-117 kph and gusts of 150-16 kph.

In the following 24-48 hours, the storm is forecast to shift west-southwest.