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upper course 上游。

upper crust

Dongshen - hong kong water supply scheme to channel dongjiang water to flow southward to shenzhen requires to convert one of the tributaries flowing north to dongjiang - the shima river - into an artificial canal by pumping of water from the shima river from its lower course to its upper course 東深供水工程,引東江水南流至深圳市,需將其中一條原本由南向北流入東江的支流石馬河變成一條人工運河,河水由下游抽回上游,逆流而上,工程因而相當艱巨。