Nanxi He

Nanxi He Sông Nậm Thi
Old border bridge between Hekou and Lào Cai
Data
location	Yunnan Province , People's Republic of China
River system	Red river
Drain over	Red River  → Gulf of Tonkin
muzzle	in Lào Cai in the Red River Coordinates: 22 ° 30 ′ 19 ″  N , 103 ° 57 ′ 56 ″  E 22 ° 30 ′ 19 ″  N , 103 ° 57 ′ 56 ″  E
Left tributaries	Sicha He, Namuguo He
Reservoirs flowed through	Zhuangzhai Reservoir 23 ° 20 ′ 39 ″  N , 103 ° 32 ′ 40 ″  E

The nanxi river ( Chinese  南溪河 , viet. Sông Nam Thi , during the colonial period Namti or Nami-ti called) is a tributary of the Red River (Yuanjiang) in the south-western Chinese province of Yunnan . In its lower reaches it is the border river between the Chinese district Hekou and the Vietnamese province Lào Cai up to its confluence with the Red River in the provincial capital of the same name .

Larger tributaries are the Namuguo He and the Sicha He , which the Wujiazhai Railway Bridge ( Viaduc de Faux-Namti ) of the Yunnan Railway spans in the Pingbian Autonomous County .