Nonni River

(also Nen River, Nun Chiang), a river in northeastern China; the largest tributary (left) of the Sungari River. It is 1,089 km long and drains an area of 244,000 sq km. Rising on the slopes of the Ilkuri Mountains, the river meanders for a considerable distance through the Sung-liao Plain, frequently dividing into branches and channels. In its lower course the width ranges from 500 m to 1,000 m; during the summer floods, caused by monsoon rains, the river broadens to 15–20 km. The average discharge in the lower reaches is about 700 cu m per sec. The river freezes over in November and thaws in April. It is navigable as far as Chichihaerh (Tsitsihar), and shallow-draft vessels can travel as far as Nenchiang (Nunkiang). The river is also used for floating timber.