The basin range of hanbei river.

hanbei river is named after its location in the north of the Han River. It lies between 112 38 ′ ~ 113 57 ′ east longitude and 3 3 ′ ~ 31 11 ′ north latitude, and is the main tributary of the left bank of the lower reaches of the Hanjiang River.

the total length of the main stream is 242km (including 56km in Xiaogan area). The river slope is .22‰, and the drainage area is 634 square kilometers. The upper section of Tianmen River (from Heyuan to Tianmen Wanjiatai) is 145 kilometers long, with a river slope of .58‰. , with a catchment area of 2536 square kilometers. The lower section from Wanjiatai to Xingou Gate is 97 kilometers long (including 56 kilometers in Xiaogan area), and the bottom of the channel is 3 meters wide, with an average gradient of .2‰. , compound section, dike distance is 5 ~ 75m wide.

the river system in the basin is well developed, with more than 2 tributaries in the upper section, most of which are distributed on the left bank. The larger ones are Jihe River, Sima River, Shangluo Temple River, Yonglong River, Xihe River and Donghe River. The main tributaries of the lower section are backwater and rich water. Dafu Water, the largest tributary of hanbei river, originated from Call Dog Mountain in Dahongshan District, Suizhou.