Dak Toa irrigation dam in Kon Ray district, Kon Tum province__Photo: Cao Nguyen/VNA
Hoang Van Bay
Director of the Water Resources Management Department
Ministry of Natural Resources and Environment
Overview of Vietnam’s water resources
Vietnam has 108 river basins with around 3,500 big rivers and streams with a length of 10 km or more each. That dense river network is divided into nine systems each having a catchment area of 10,000 km² or larger, including the Red River, Thai Binh, Bang Giang-Ky Cung, Ma, Ca, Vu Gia-Thu Bon, Ba and Dong Nai rivers, and Mekong River. The country’s total annual surface runoff is around 830-840 billion m³. However, about 60 percent of this water volume is generated overseas while 310-320 billion m³ of water originate inside the country. In addition to surface water, Vietnam’s groundwater resources are abundant with the total potential reserves estimated at roughly 63 billion m³ per year which are distributed in 26 areas across the country but mostly concentrated in the northern delta, southern region and Central Highlands.
The country has built, is building or has planned to build a total of 2,900 hydropower and irrigation reservoirs with a total capacity of over 65 billion m3. All over the country, more than 2,000 reservoirs with a total water storage capacity of more than 34 billion m3 have been put into operation, while 240 others capable of containing over 28 billion m3 of water are under construction. Of these 2,900 reservoirs, irrigation storage ponds number 2,000 but contribute just nearly 9 billion m3 or 14 percent to the total capacity of the reservoir network. Hydropower lakes are fewer but have a storage capacity totaling around 56 billion m3, representing 86 percent of the network’s total capacity. River basins with reservoirs of large storage capacity include the Red River with a capacity of over 30 billion m3, Dong Nai river, over 10 billion m3; and Se San, Ma, Ca, Huong, Vu Gia-Thu Bon and Srepok rivers, 2-4 billion m3 each.
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