Manasi River

The Manasi River (simplified Chinese: 玛纳斯河; traditional Chinese: 瑪納斯河; pinyin: Mǎnàsī hé, Uyghur: ماناس دەرياسى), also known as the Manas River, is the largest endorheic river on the northern slopes of the Tianshan Mountains in Xinjiang, China. It originates from the Erenhabirga Mountains (依连哈比尔尕山) in Hejing County, Bayingolin Mongol Autonomous Prefecture, and flows northwest through Manas County, ultimately entering Lake Manas. The river stretches approximately 504.3 km (313.4 mi) in length.

The Manas River marks the boundary between Changji Hui Autonomous Prefecture, Shihezi City, Tacheng Prefecture, and Karamay City. Historically, it provided essential irrigation for surrounding oases and agricultural lands. However, with the rise of intensive irrigation since the 1960s, much of the river’s flow has been diverted, resulting in the desiccation of Lake Manas.

The name "Manas" is derived from the Mongolian word "manaa" (Mongolian: ᠮᠠᠨᠠᠭ᠎ᠠ), meaning "to guard" or "to patrol", combined with the suffix "-s" (ᠰ), forming "Manas" or "patroller." This etymology is documented in Qing-era works such as Xinjiang Tuzhi (新疆图志), which attributes the name to patrol forces stationed along the riverbanks during the late Qing dynasty.

The river lends its name to Manas County, which depends heavily on the Manas River for agriculture, industry, and drinking water. Numerous reservoirs and canals—including the Jiahezi Reservoir—form an integrated water system supporting over 500,000 residents in the basin.