Northwest China's Qinghai Province on Saturday issued a top level flood alert at Tuotuo River due to torrential rains. 

The provincial hydrological department announced the alert in a flood warning document, saying that the hydrologic station at the Tuotuo River observed water flow at 852 cubic meters per second, reaching the level of extreme flooding.

The document also urges government departments in regions along the river to take precautions and evacuate residents, especially in Tanggula Town and Zhiduo County.

Tuotuo River, is one of the three sources of the Yangtze River, the longest river in China and the third longest in the world. It originates from glaciers of the Jianggendiru Snow Mountains and gathers water from a number of glaciers in the region. 

The river freezes from October to April next year, and swells in June as the glaciers melt. Its water levels reach the peak in August. 

(All images via CFP)

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