RED RIVER BASIN
The names of the Red River
In China, the river is known as the Hóng and, similarly, in Vietnamese as the Hông. Its three main tributaries are the Black (the Da in Vietnamese), the Thao and the Lô, which converge near Viêt Trì in Vietnam’s Phú Tho Province.
The Red River’s delta covers almost 120 KM², and produces nearly a third of Vietnam’s rice.
The waters of the Red
The Red River rises in mountains south of Dali in China’s Yunnan Province, and then descends 1,149 KM through Vietnam to exit into the Gulf of Tonkin. The river flows past Hanoi’s capital, Hanoi. Rainfall is uneven across the basin and ranges from 700 to 4,200 mm a year, about 80% of which falls between May and October. Average annual discharge from the river is about 136 KM³, the equivalent of some 54 million Olympic swimming pools. 61% of this water is derived from Vietnam. Flooding is a significant issue on the Red River. In the Delta, the average altitude is 3-5 meters lower than maximum flood levels. As a consequence, much hydraulic infrastructure in the basin is devoted, in whole or in part, to flood control. Conversely, infrastructure can also cause flooding downstream. Vietnam regularly complains of unannounced dam releases from Chinese hydropower dams.
A development river
The Red River is heavily developed. In China, there are 41 hydropower dams in China, 2 multi-purpose dams and 25 irrigation dams in the Red River Basin; in Vietnam, there are 25 hydropower dams, 3 multi-purpose dams, and 9 irrigation dams. There are some immense reservoirs in the Basin. The Ban Chat reservoir in Vietnam stores some 2.1 billion m3 of water, the Tha Bac stores almost 2.5 billion m³, while the Tuyên Bac stores about 2.3 billion m³.
The Red River’s delta covers almost 120 KM², and produces nearly a third of Vietnam’s rice. 47% of the Delta is devoted to agricultural production. In Vietnam, the river is heavily exploited for agriculture, with extensive irrigation throughout – 10,800 KM of irrigation canals, 9,300 KM of drainage canals, 3, 828 irrigation sluices, and 4,300 drainage sluices (for both river and sea).
A dirty river
High population densities and under-regulated industry cause considerable pollution challenges. In Vietnam, two primary pollution indicators, Ammonia-nitrogen and Biochemical Oxygen Demand exceed national water quality standards by several fold. The problems are worst during the dry season, when river flows are low.
RED RIVER BASIN MAP
Click below to download the Red River Basin map.