Caoyun system

The Caoyun System (simplified Chinese: 漕运系统; traditional Chinese: 漕運系統; pinyin: Cáoyùn Xìtŏng) was a water and land based grain transportation system begun in China during the Qin dynasty (221 BCE – 206 BCE) which saw continual use until the Qing dynasty (1644–1911). The primary purpose of the caoyun was tax collection, since grain was a major payment method accepted by the imperial administration. The system also played a secondary role as a distribution network for army provisions whilst management of shipbuilding and tariffs also fell within its ambit.

In 647 BCE, the State of Jin suffered major crop failure. Duke Mu of Qin despatched a large fleet of ships manned by Corvée labour from his capital at Yong (雍) in modern-day Fengxiang County, Shaanxi Province. The ships carried several thousands of tons of cereal and proceeded along the Wei, Yellow and Fen Rivers before arriving at the Jin capital Jiang (绛) (south east of modern-day Yicheng County, Shanxi Province). Later, in 486 BCE, King Fuchai of Wu linked the Yangtze and Huai Rivers by excavating the Han Ravine (邗沟) so that water flowed from the Yangtze through the Lakes Fanliang (樊梁湖), Bozhi (博芝湖) and Sheyang (射阳湖) into the Wei at Huai'an. This waterway was subsequently used to transport provisions for the army. Three years afterwards King Fuchai further extended the Han Ravine via the Heshui Canal (荷水运河) to connect with the Si River in Shandong Province.

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