Experts have blamed small hydropower plants and a lack of attention to local drainage systems as the cause for recent flooding.
Su Pan 1 Hydropower Plant discharged water unexpectedly
According to the Steering Committee for Natural Disaster Prevention and Control, as of August 11, floods and landslides have resulted in 10 deaths and six missing cases.
The estimated damage is over VND1trn (USD43m).
From August 5 to 10, heavy rains with the average 150-300mm of rainfall occurred in the Central Highlands.
The rainfall in Buon Ma Thuot City reached 402mm and 353mm in Dak Nong Province. The rainfall in the southern region in the first 10 days of August also reached 100-250mm.
Hoang Phuc Lam, deputy director of the National Center for Meteorological and Hydrological Forecasting said such huge amount of rainfall was very unusual. The rainy season in the Central Highlands and southern region will last until October.
In Phu Quoc Island, the annual rainfall is around 2,800mm and the rainfall in the first 10 days of August is usually around 163mm. However, this year, the rainfall from August 1 to 10 reached 1,167mm.
"This record-breaking figure is the highest rainfall since 1978," he said.
Vu Trong Hong, chairman of Vietnam Irrigation Association, said the authorities must review the responsibilities of small hydropower plants and whether they had forgotten to consider the drainage system into the urban planning.
"There maybe three to four hydropower plants on a river. If the first plant discharges water then the plants below must also discharge water, causing floods upon floods," he said.
Small hydropower plants in Vietnam often have the average capacity to deal with some million to hundreds of thousands of cubic metres of water. In 2012, the government banned new small hydropower plants because they can cause floods.
However, in the past years, local authorities asked for permission to build new plants to cope with electricity shortages.
As a result, even a stream can have its own hydropower plant. At some places, they dug the stream so that it can be deeper and create stronger current flow.
Most small hydropower plants are located from Quang Nam Province. Hong suggested that the government must have evacuation policies for those places.
"For example, the locals should move to live somewhere else during the rainy season and return to the hometown to work in the fields during the dry season," Hong said.
Hong also said it was very strange when Phu Quoc Island was flooded since it is not prone to storms like the Philippines.
"Did Phu Quoc Island develop too fast? Everyone rushed to buy lands and houses without taking into account road and drainage system building. Maybe the flood was caused because the old drainage system was ruined?" he said.
According to Hong, when building new urban areas or upgrade the villages, the local authorities often build roads without planning so this problem must be reviewed immediately.
The large number of hydropower projects in Nghe An Province have greatly affected the lives of local people.
Violations in the construction of a number of hydropower plants in the northern mountainous province of Lai Chau have been blamed on poor management by local authorities.
Running across the northwest highlands of Lai Chau, Dien Bien, Son La and Hoa Binh before going down to Phu Tho to merge into the Red River, DA River makes a great contribution to the national grid system.